2035 LQ GP CERTIFIED EIR (2013) - Fully Assembeled (No Appendices)
ENVIRONMENTAL IMPACT REPORT
(SCH # 2010111094)
FOR THE
CITY OF LA QUINTA GENERAL
PLAN
Prepared For
City of La Quinta
78-495 Calle Tampico
La Quinta, CA 92253
Prepared By
Terra Nova Planning & Research, Inc.®
42635 Melanie Place, Suite 101
Palm Desert, CA 92211
Certified February 19, 2013
Terra Nova/La Quinta General Plan
Draft Environmental Impact Report
Table of Contents
i
Table of Contents
List of Exhibits iv
List of Tables v
List of Appendices vii
Environmental Summary Matrix M-1
I. INTRODUCTION AND PROJECT DESCRIPTION I-1
A. Lead Agency I-1
B. Introduction I-1
C. Document Organization I-2
D. CEQA And Other Requirements I-2
E. Project Location And Description I-4
F. Statistical Summary: General Plan Land Use I-15
II. REGIONAL ENVIRONMENTAL SETTING II-1
A. Aesthetics II-1
B. Agriculture ResourcesII-2
C. Air Quality And Greenhouse Gasses II-3
D. Climate II-4
E. Biological Resources II-5
F. Cultural Resources II-6
G. Geology And Soils II-7
H. Topography II-8
I. Hazards And Hazardous Materials II-11
J. Hydrology And Water Quality II-11
K. Existing Land Use II-14
L. Surrounding Land Use II-16
M. Mineral Resources II-17
N. Noise II-17
O. Population And Housing II-18
P. Public Services And Utilities II-19
Q. Recreation II-23
R. Transportation/Traffic II-24
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III. EXISTING ENVIRONMENTAL CONCERNS, PROJECT IMPACTS AND
MITIGATION MEASURES III-1
A. Aesthetics III-1
1. Existing Conditions III-2
2. Project Impacts III-4
3. Mitigation Measures III-6
B. Agricultural Resources III-7
1. Existing Conditions III-7
2. Project Impacts III-10
3. Mitigation Measures III-12
C. Air Quality And Greenhouse Gases III-13
1. Existing Conditions III-15
2. Project Impacts III-25
3. Mitigation Measures III-33
D. Biological Resources III-36
1. Existing Conditions III-37
2. Project Impacts III-51
3. Mitigation III-53
E. Cultural Resources III-55
1. Existing Conditions III-57
2. Project Impacts III-65
3. Mitigation Measures III-66
F. Geology And Soils III-67
1. Existing Conditions III-68
2. Project Impacts III-88
3. Mitigation Measures III-90
G. Hazards And Hazardous Materials III-91
1. Existing Conditions III-92
2. Project Impacts III-97
3. Mitigation Measures III-100
H. Hydrology III-101
1. Existing Conditions III-102
2. Project Impacts III-113
3. Mitigation Measures III-114
I. Land Use And Planning III-115
1. Existing Conditions III-116
2. Project Impacts III-121
3. Mitigation Measures III-131
J. Mineral Resources III-131
1. Existing Conditions III-131
2. Project Impacts III-134
3. Mitigation Measures III-134
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K. Noise III-135
1. Existing Conditions III-135
2. Project Impacts III-152
3. Mitigation Measures III-163
L. Population And Housing III-165
1. Existing Conditions III-165
2. Project Impacts III-166
3. Mitigation Measures III-169
M. Public Services & Utilities III-170
N. Recreational Resources III-194
1. Existing Conditions III-194
2. Project Impacts III-197
3. Mitigation Measures III-198
O. Transportation/Traffic III-198
1. Existing Conditions III-205
2. Project Impacts III-221
3. Mitigation Measures III-229
P. Water Resources & Quality III-238
1. Existing Conditions III-239
2. Project Impacts III-250
3. Mitigation III-256
IV. UNAVOIDABLE SIGNIFICANT IMPACTS IV-1
V. PROJECT ALTERNATIVES V-1
A. Introduction V-1
B. Statement Of Project Objectives V-3
C. Alternative Projects Selected For Detailed Analysis V-5
1. No Project Alternative V-5
2. Alternative 1 V-10
3. Alternative 2 V-14
D. Alternative Projects Analysis V-18
E. Environmentally Superior Alternative V-64
VI. SHORT-TERM USE VERSUS LONG-TERM PRODUCTIVITY VI-1
VII. IRREVERSIBLE AND IRRETRIEVABLE COMMITMENT OF
ENVIRONMENTAL RESOURCES VII-1
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VIII- GROWTH INDUCEMENT AND CUMULATIVE IMPACTS VIII-1
IX- ORGANIZATIONS, PERSONS AND DOCUMENTS CONSULTED IX-1
List of Exhibits
Exhibit I-1 Regional Map I-6
Exhibit I-2 Vicinity Map I-7
Exhibit I-3 General Plan Planning Area Boundaries I-8
Exhibit I-4 2002 General Plan Land Use Map I-14
Exhibit I-5 Preferred Alternative Land Use Map I-24
Exhibit II-1 Topography Map II-10
Exhibit III-1 Vegetation Communities III-40
Exhibit III-2 CNDDB, Critical Habitat & Modeled Habitat III-47
Exhibit III-3 Land Ownership And Conservation Areas III-49
Exhibit III-4 Paleontological Sensitivity Map III-60
Exhibit III-5 Cultural Resources Survey Map III-64
Exhibit III-6 Geologic Map Of The Planning Area III-72
Exhibit III-7 Wind Erosion Susceptibility Map III-78
Exhibit III-8 Faults And Historical Seismicity Map III-83
Exhibit III-9 Seismic Hazards III-87
Exhibit III-10 FEMA Flood Hazard Zones And Flood Control Facilities III-108
Exhibit III-11 Mineral Resource Zone Map III-133
Exhibit III-12 Land Use And Noise Compatibility III-138
Exhibit III-13 Noise Monitoring Locations In The Study Area III-143
Exhibit III-14 Existing Truck And Bus Routes III-146
Exhibit III-15 Existing Airport Noise Contours III-150
Exhibit III-16 Future Airport Noise Contours (Jacqueline Cochran Airport) III-161
Exhibit III-17 Existing (2010) Average Daily Traffic Volumes III-212
Exhibit III-18 General Plan Roadway Classifications III-214
Exhibit III-19 General Plan Street Cross Sections III-215
Exhibit III-20 General Plan Build Out (2035) Average Daily Volumes III-226
Exhibit III-21 Prescribed Intersection Improvement III-233
Exhibit V-1 No Project Alternative Land Use Map V-6
Exhibit V-2 Alternative 1 Land Use Map V-13
Exhibit V-3 Alternative 2 Land Use Map V-17
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List of Tables
Table I-1 Preferred Alternative General Plan Update Land Use Acreage Summary I-16
Table I-2 General Plan Update Build Out Summary: City Limits I-17
Table I-3 General Plan Update Build Out Summary: Sphere of Influence I-17
Table I-4 General Plan Update Build Out Summary: Entire Planning Area I-18
Table I-5 City of La Quinta General Plan Proposed Land Use Designations I-19
Table III-1 Emissions Thresholds For SCAQMD III-14
Table III-2 State And Federal Ambient Air Quality Standards III-19
Table III-3 Pm10 Monitoring Data For The Coachella Valley III-20
Table III-4 Pm2.5 Monitoring Data For The Coachella Valley III-21
Table III-5 Ozone Monitoring Data III-22
Table III-6 Construction Emissions For The Planning Area III-27
Table III-7 Projected Daily Emissions At General Plan Build Out III-29
Table III-8 GHG Emissions From Construction Of The General Plan III-31
Table III-9 GHG Emissions From Operation At General Plan Build Out III-31
Table III-10 Air Quality Control Methods III-34
Table III-11 Special Status Plants In The La Quinta General Plan Area And Vicinity III-43
Table III-12 Special Status Reptiles In The La Quinta General Plan Area And Vicinity III-43
Table III-13 Special Status Bird Species In The La Quinta General Plan Area
And Vicinity III-43
Table III-14 Special Status Mammal In The La Quinta General Plan Area And Vicinity III-44
Table III-15 Horizontal Peak Ground Accelerations And Seismic Intensities III-80
Table III-16 Existing Land Use Designations Within City Limits III-118
Table III-17 2002 Land Use Designations Within Sphere Of Influence III-119
Table III-18 2002 Land Use Designations Within Planning Areas III-120
Table III-19 Existing Land Use Summary III-121
Table III-20 Proposed Land Use For City Limits III-123
Table III-21 Riverside County Vista Santa Rosa Land Use III-124
Table III-22 Riverside County Land Use North Sphere III-125
Table III-23 Riverside County Land Use Sphere Summary III-125
Table III-24 General Plan Update East Sphere Land Use III-126
Table III-25 General Plan Update Land Use North Sphere III-126
Table III-26 General Plan Update Land Use Sphere Summary III-127
Table III-27 Proposed Land Use Summary III-129
Table III-28 Exterior Noise Limits III-139
Table III-29 Existing (Ambient) Short-Term Noise Level Measurements III-140
Table III-30 Existing (Ambient24-Hour Noise Level Measurements III-142
Table III-31 City Of La Quinta Hourly Traffic Flow Distribution III-144
Table III-32 Existing Noise Exposure Adjacent To General Plan Update Study
Area Roadways III-147
Table III-33 Year 2035 Build Out Conditions Noise Contours III-153
Table III-34 Year 2035 Preferred Alternative Noise Contour Comparison III-157
Table III-35 Desert Sands Unified School District Enrollment And Capacity III-172
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Table III-36 Coachella Valley Unified School District Enrollment And Capacity III-173
Table III-37 Potential Student Generation La Quinta City Limits III-174
Table III-38 Potential Student Generation Sphere Of Influence III-175
Table III-39 Potential Student Generation Planning Area Summary III-175
Table III-40 Estimated Electricity Usage Rates III-183
Table III-41 Natural Gas Consumption Factors III-185
Table III-42 Solid Waste Generation At General Plan Build Out III-192
Table III-43 Level Of Service Description III-201
Table III-44 Intersection Level Of Service Descriptions III-202
Table III-45 City Roadway Classifications Level of Service Volumes/Capacity Values
(Average Daily Trips – ADT) III-203
Table III-46 Existing Daily Volumes And Capacity Summary III-216
Table III-47 Existing Peak Hour Intersection LOS III-219
Table III-48 General Plan Build Out (2035) Roadway Segment Analysis III-222
Table III-49 General Plan Build Out (2035) Intersection Analysis III-227
Table III-50 Coachella Valley Water District Annual Water Production III-242
Table III-51 Estimate Of Existing Water Service Demands III-251
Table III-52 Estimate Of Water Service Demands At Build Out III-252
Table III-53 Estimate Of Water Service Demands From New Development III-253
Table V-1 Preferred Alternative Build Out Summary: City Limits V-2
Table V-2 Preferred Alternative Build Out Summary: Sphere of Influence V-2
Table V-3 Preferred Alternative Build Out Summary: Entire Planning Area V-3
Table V-4 No Project Alternative Build Out Summary: City Limits Only V-7
Table V-5 No Project Alternative Build Out Summary: Sphere-of-Influence V-8
Table V-6 No Project Alternative Build Out Summary: Planning Area Total V-9
Table V-7 Alternative 1 Build Out Summary: City Limits Only V-10
Table V-8 Alternative 1 Build Out Summary: Sphere-of-Influence V-11
Table V-9 Alternative 1 Build Out Summary: Planning Area Total V-12
Table V-10 Alternative 2 Build Out Summary: City Limits Only V-14
Table V-11 Alternative 2 Build Out Summary: Sphere-of-Influence V-15
Table V-12 Alternative 2 Build Out Summary: Planning Area Total V-16
Table V-13 Cumulative Daily Emissions No Project Alternative (Lbs./day) V-24
Table V-14 GHG Emissions for the No Project Alternative V-25
Table V-15 Cumulative Daily Emissions Alternative 1 (Lbs./day) V-26
Table V-16 GHG Emissions for Alternative 1 V-27
Table V-17 Cumulative Daily Emissions Alternative 2 (Lbs./day) V-28
Table V-18 GHG Emissions for Alternative 2 V-29
Table V-19 Year 2035 Preferred Alternative Noise Contour Comparison V-39
Table V-20 Potential School Enrollment at General Plan Build Out,
No Project Alternative V-44
Table V-21 School Enrollment at General Plan Build Out, Alternative 1 V-44
Table V-22 School Enrollment at General Plan Build Out Alternative 2 V-45
Table V-23 Estimated Solid Waste Generation for La Quinta Planning Area No Project V-52
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Table V-24 Solid Waste Generation for Planning Area Alternative 1 V-52
Table V-25 Solid Waste Generation for Planning Area Alternative 2 V-53
Table V-26 Comparison of Land Use Alternatives V-55
Table V-27 No Project Alternative Forecast Year 2035 Peak Season V-57
Table V-28 Alternative 1 Forecast Year 2035 Peak Season V-58
Table V-29 Alternative 2 Forecast Year 2035 Peak Season V-59
Table V-30 No Project Alternative Water Demand V-61
Table V-31 Alternative 1 Water Demand V-62
Table V-32 Alternative 2 Water Demand V-64
List of Appendices
A. Draft Environmental Impact Report, Notice of Preparation (NOP) and Responses to
NOP. Prepared by Terra Nova Planning & Research, Inc., November 22, 2010.
B. Air Quality and Greenhouse Gas Impact Analysis for the La Quinta General Plan Update
2010. Prepared by Terra Nova Planning & Research, Inc., May 2012.
C. City of La Quinta General Plan Update: Biological Resources. Prepared by AMEC
Earth & Environmental Inc., June 2010.
D. Cultural Resources Technical Report City of La Quinta General Plan 2010 Update.
Prepared by CRM TECH, July 8, 2010.
E. Technical Background Report to the Safety Element of the La Quinta 2035 General Plan
Update, Seismic Hazards, Geologic Hazards, Flooding Hazards. Prepared by Earth
Consultants International, Inc., June 2010 Revised September 7, 2010.
F. City of La Quinta General Plan Update Noise Element Technical Report. Prepared by
Urban Crossroads, June 3, 2011.
G. Paleontologic Resources Technical Report City of La Quinta General Plan 2010 Update.
Prepared by CRM TECH, August 12, 2010.
H. City of La Quinta General Plan Circulation Element Update Traffic Impact Analysis.
Prepared by ITERIS, May 14, 2012.
I. Water Supply Study for the proposed La Quinta General Plan update 2010. Prepared by
Terra Nova Planning & Research, Inc. June 21, 2011.
J. Final Environmental Impact Report (Response to Comments). Prepared by Terra Nova
Planning & Research, Inc. November 2012.
Terra Nova/ La Quinta General Plan EIR
Environmental Summary Matrix
M-1
ENVIRONMENTAL SUMMARY MATRIX
This Environmental Impact Report has been prepared to analyze the potential impacts associated with the implementation of the City of La Quinta General Plan.
Under the California Environmental Quality Act (CEQA), General Plans and their amendments are considered “projects” which require thorough analysis in the
form of an EIR. Therefore, this EIR is an integral part of the General Plan development process.
The area addressed in this Environmental Impact Report includes the City’s current corporate boundary and Sphere of Influence, referred to in this document as
the City of La Quinta General Plan Update Planning Area.
City Limits
The incorporated limits of the City of La Quinta encompass 35.7± square miles, which are developed for a range of residential, resort and resort residential, commercial
and open space uses. Lands within the City limits may also be described as follows:
Portions of Section 25 and all of Section 36, Township 5 South, Range 6 East; Sections 1,12,13,24, and 25, Township 6 South, Range 6 East; portions of Section
17 18, 19, 20,28,29, and 30, and all of Sections 31 and 32, Township 5 South, Range 7 East; portions of Section 26, 35 and all of Sections 4, 5,
6,7,8,9,10,15,16,17,18, 19, 29, 21, 22, 27, 28, 29, 30, 33 and 34, Township 6 South, Range 7 East; Sections 4 and 5, Township 7 South, Range 7 East of the San
Bernardino Baseline and Meridian.
Sphere of Influence
The Sphere areas in the Planning Area, total 12.6± square miles. One of these occurs to the north of the City’s corporate limits, and the other to the east of the City’s
corporate limits. Lands included in the City’s Sphere are those identified by the Local Agency Formation Commission (LAFCo) as being a logical extension of the City
in the long term. Only if these lands are annexed will the City have jurisdiction over their development. All lands in the Sphere currently fall under the jurisdiction of
the County of Riverside.
Portions of Section 18, Township 5 South, Range 7 East; and portions of Section 12, 13, 26 and 35 and all of 11, 14, 23, 24, 25, and 36, of Township 6 South,
Range 7 East; all of Section 19, 30, 31 of Township 6 South, Range 8 East of the San Bernardino Baseline Meridian.
This EIR assesses the environmental impacts that may result as a consequence of approval and implementation of the proposed land use scenario and the Plan’s
goals, policies and programs, as well as buildout of the entire area. The following discussion briefly summarizes each category of analysis, including existing
conditions, project impacts and applicable mitigation measures recommended to reduce impacts to acceptable or insignificant levels. Levels of impact include the
following:
Significant Impacts: Those impacts that constitute a potentially significant adverse change in the environment.
Insignificant Impacts: Those impacts that, by virtue of the environmental conditions, predisposing existing development, or the implementation of mitigation
measures, are reduced to acceptable or “insignificant” levels.
Unavoidable Impacts: Those impacts that occur as a result of project development whose adverse effects cannot be entirely eliminated or reduced to a level of
insignificance.
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Existing Conditions Project Impacts Mitigation Measures
AESTHETICS
The La Quinta General Plan Update Planning Area
is comprised of many land uses, including
residential, commercial, resort facilities, office
parks, agricultural facilities, golf courses, open
spaces, and vacant land. These land uses are built
primarily on the Valley floor and within the Cove.
Development within the City Limits is generally
built at lower densities, and buildings throughout
the Planning Area tend to be low-rise structures.
Views of local mountains and scenic vistas
throughout the incorporated portions of the City are
generally good, however suburban development,
including buildings, walls, and mature landscaping
can limit views in certain places.
The eastern Sphere of Influence is rural and
sparsely developed. Land uses in the Sphere
include single family residential, agricultural
production and equestrian uses. There is also a
considerable amount of fallow vacant land once
used for agriculture. Views of local mountains and
scenic vistas throughout this portion of the Sphere
are preserved and unobstructed due to sparse
development. As a result of this rural character, the
aesthetic quality is more open and views of
surrounding mountains are less restricted when
compared to the more developed portions of the
region.
The General Plan Update does not propose changes
in land use intensities or densities, insofar as no
new land use designations are being considered.
Policies and programs in the General Plan Update
are consistent with the existing character of
development in the City, and do not propose
intensification or densification of the City or
Sphere. Visual character impacts within the City,
therefore, are expected to be less than significant.
Scenic Resources includes trees, rock outcroppings, and historic buildings that are visible from a state scenic highway. Currently, there are no state scenic highways that run through La Quinta or the Sphere of Influence. Therefore, impacts to scenic resources along a state scenic highway will be less than significant. Light and glare impacts are associated with increased urbanization. Within the City limits, the majority of lands are developed, and daytime and nighttime skies are already affected to a limited extent by light and glare. The adoption of the General Plan Update will facilitate similar development patterns in the City to those that exist today. Further, the General Plan Update maintains policies and programs currently in effect that limit lighting, and the City’s Municipal Code prohibits light spillage onto neighboring properties. Therefore, implementation of the General Plan Update will have a less than significant impact on light and glare impacts.
None required.
Alternatives: Alternative 1 would result in less
development within the planning area, and
therefore would reduce potential aesthetic impacts
to some degree. All alternatives, however, result in
development of currently vacant lands, and will
therefore have similar levels of impact on aesthetic
resources.
Terra Nova/ La Quinta General Plan EIR
Environmental Summary Matrix
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Existing Conditions Project Impacts Mitigation Measures
AGRICULTURAL RESOURCES
Agricultural uses in the General Plan Update
Planning Area are located primarily within the
Sphere of Influence, however a few small citrus
groves are located within City limits.
Undeveloped portions of incorporated La Quinta
and the Sphere are located in areas designated as
Prime Farmland, Farmland of Statewide
Importance, Unique Farmland or Lands of
Statewide Importance. In 2008, there were
approximately 1,700 acres of important agricultural
land located in the City, and 7,391 acres in the
Sphere of Influence, for a total of 9,091 acres.
582 acres of land with Williamson Act contracts are located within the Sphere of Influence. Based on 2008 Riverside County data, approximately 218.9 acres were in renewal, and 363 acres were in non-renewal.
Implementation of the General Plan Update does
not require landowners to immediately convert
farmland to new land uses. However, new
development proposed will be required to develop
according to new land use designations. As a result,
agricultural lands will be affected by new growth
and development. There are currently over 545,000
acres of important farmland in Riverside County1.
The 7,391 acres of land designated as important
farmland represents 1.3% of the total important
farmland in the County. The eventual loss of these
lands will not significantly impact agriculture in the
region. The implementation of the General Plan Update will facilitate development on lands currently used for agriculture in the Sphere of Influence. The General Plan Update does not mandate that landowners terminate agricultural production, but provides regulations when development does occur on these lands. The General Plan Update includes the master planning of the Sphere, where agricultural activities occur. The master plan is required to consider and include community character, and may include agriculture as an allowed land use. Finally, none of the policies, programs or land use designations of the General Plan Update will apply to any of these lands if they are not annexed to the City.
Mitigation measures include the master planning of
the eastern Sphere to reflect the agricultural
character, the provision of buffers between new
development and agricultural uses, and the
incorporation of traditional agricultural plantings in
public spaces. These mitigation measures will
assure that impacts associated with agricultural
resources are reduced to less than significant levels.
Alternatives: Build out of each of the alternatives
would result in similar impacts on agricultural
resources. The No Project Alternative, which
would maintain the County designations on the
Sphere area, could be the least impacting on
agricultural resources.
Terra Nova/ La Quinta General Plan EIR
Environmental Summary Matrix
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Existing Conditions Project Impacts Mitigation Measures
AIR QUALITY
In the Coachella Valley air quality has exceeded
state and federal standards for ozone and particulate
matter. SCAQMD studies indicate that most ozone
is transported to the Salton Sea Air Basin from the
upwind South Coast Air Basin, which contains
large metropolitan areas including Los Angeles. It
is difficult to quantify the amount of ozone
contributed from other air basins; however,
improved air quality in the Coachella Valley
depends upon reduced ozone emissions in the
South Coast Air Basin.
Industrialization, urban lifestyle, agricultural
practices, production and manufacturing and other
human activities result in the emission of
greenhouse gas that are contributing to global
warming and climate change, and include carbon
dioxide (CO2), methane (CH4), nitrous oxide
(N2O), tetrafluoromethane, hexafluoroethane,
sulfur hexafluoride, HFC-23 (fluoroform), HFC-
134a (s, s, s, 2 –tetrafluoroethane), and HFC-152a
(difluoroethane).
The City of La Quinta has completed a Greenhouse Gas Inventory and has prepared a Greenhouse Gas Reduction Plan as part of this General Plan Update. The intent of the Greenhouse Gas Reduction Plan is to set goals, policies, and programs that will result in the reduction of greenhouse gas emissions to targets identified in the Plan that meet the State’s mandates.
With implementation of mitigation measures, air
quality emissions from construction activities
within City limits are projected to exceed
thresholds for NOx and ROG. Even with
implementation of mitigation measures, air quality
emissions of NOx and ROG have the potential to
result in significant and unavoidable impacts from
construction activities occurring within City limits.
Construction related air quality emissions from the
development of lands within the Sphere of
Influence are projected to exceed established daily
thresholds for NOx and ROG, even with
implementation of mitigation measures.
For build out of the General Plan Update, air quality emissions have the potential to result in a cumulatively considerable net increase of CO, NOx, SOx, PM10, PM2.5, and ROG. Projections of these pollutants exceed established daily thresholds and have the potential to result in significant and unavoidable impacts. GHG emissions from construction will end once construction activities are complete. Therefore, the generation and emission of GHG’s from construction are not expected to have a long term or lasting impact and impacts to air quality from construction will be less than significant.
Implementation of the Greenhouse Gas Reduction
Plan is intended to reduce impacts associated with
the emission of greenhouse gases within City limits
to levels that are less than significant. Were the
Sphere of Influence to be annexed into La Quinta
City jurisdiction, then lands would be subject to the
Greenhouse Gas Reduction Plan and compliance
would assure that impacts to air quality from the
emission of greenhouse gases would be reduced to
levels below significance.
A number of mitigation measures are offered to
help to reduce emissions of all criteria pollutants.
These include both broad based, community-wide
mitigation, and project-specific measures.
Mitigation measures are also included to reduce
GHG emissions in the City and Sphere. However,
even with the implementation of these mitigation
measures, air quality impacts associated with all
criteria pollutants will remain significant and
unavoidable.
Alternatives: All project alternatives result in
significant impacts associated with air quality. The
In all cases, impacts remain significant and
unavoidable as they relate to air quality.
Terra Nova/ La Quinta General Plan EIR
Environmental Summary Matrix
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Existing Conditions Project Impacts Mitigation Measures
BIOLOGICAL RESOURCES
There are primarily two categories of habitat
associated with wildlife common to the planning
area. The most prevalent consists of the very
disturbed and fragmented patchwork of remnant
sand field, saltbush scrub, weedy (ruderal),
agricultural, and residential/recreational
development. Common species in this environment
are those that are capable of surviving in ruderal
plant communities or near residential, commercial,
agricultural, and golf course developments.
Another habitat category is comprised of native,
less altered habitats where the Santa Rosas and
associated alluvial fans and canyons overlap in the
western and southern portions of the Planning area.
These remaining areas of native habitat sustain both
common as well as some sensitive desert wildlife
species and plant communities.
The General Plan Area is within the planning area
for the Coachella Valley Multiple Species Habitat
Conservation Plan (MSHCP). On lands not
designated for conservation, future development
will be required to pay a mitigation fee to ensure
the future availability of funds to purchase
conservation lands. These fees are intended to
offset the potential impacts of that development on
the natural environment. Seven sensitive species
are not covered by the provisions of the MSHCP.
The ultimate build out of the General Plan Planning Area has the potential to significantly impact biological resources by reducing native habitat areas and directly affecting fauna. However, the majority of lands on which development will occur are on the Valley floor, in areas already impacted by urban development or agricultural activities. These areas are part of the MSHCP, and new development projects will be required to pay mitigation fees associated with the MSHCP to allow for the preservation of habitat and species in designated conservation areas. Areas where non-covered sensitive species occur are identified in the General Plan, and the Plan requires the preparation of special studies for projects proposed in those areas. Those studies will provide an assessment of the potential impacts, and recommend mitigation measures if necessary. The General Plan also designates Natural Open Space for hillside areas on the west and southwest portions of the City, which are areas of potential habitat for the endangered Peninsular Bighorn Sheep. The Natural Open Space designation will not result in development in these areas, and will protect these lands for the long term.
Existing regulations, including the provisions of the
MSHCP, the requirements enforced by the
California Department of Fish and Game, the US
Fish and Wildlife Service and the US Army Corps
of Engineers will continue to be enforced by the
City. The General Plan acknowledges these
requirements, and includes policies to maintain
their implementation for future projects as they are
proposed.
The EIR includes requirements for site specific and
species specific studies in areas of habitat for
species of concern; the implementation of the
MSHCP; the adherence to state and federal
regulations; and the preservation of open space
areas. With implementation of these mitigation
measures, impacts associated with biological
resources will be reduced to less than significant
levels.
Alternatives: All alternatives propose new
development, each of which would be subject to the
same standards imposed under the Preferred
Alternative. Therefore, no alternative is considered
superior in regard to impacts associated with
biological resources, although the No Project
Alternative and Alternative 1 could result in
slightly more preservation of habitat.
Terra Nova/ La Quinta General Plan EIR
Environmental Summary Matrix
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Existing Conditions Project Impacts Mitigation Measures
CULTURAL RESOURCES
Cultural Resources are important for understanding
the history and heritage of the community, and for
preserving important archaeological and
paleontological resources. The City of La Quinta
and the Coachella Valley region have a rich
cultural past, as discovered through recent
paleontological and archaeological surveys.
The archaeological resources found within the
General Plan Update Planning Area are remnants
from prehistoric peoples who took advantages of
the resources in ancient Lake Cahuilla. Cultural
surveys have identified approximately 500
archaeological sites, both historic and prehistoric,
in the Planning Area. In addition to these sites,
approximately 170 isolates, or localities with fewer
than three artifacts, have also been discovered. The
majority of these archaeological finds are from
Native American tribes and include pottery, burned
animal bone, grinding stones, chipped stone,
cremation and other remains. Past surveys have
highlighted approximately 280 buildings and other
built features in the General Plan Update Planning
Area as having the potential to be historically
significant.
Areas that are determined to be of “high” paleontological sensitivity include areas made up of Pleistocene sediments, and sediments from ancient Lake Cahuilla beds. Pleistocene sediments are located in the southwestern portion of the Planning Area. Areas determined as being of “low” paleontological sensitivity are areas made up of Granitic Rock. These areas are located in the southwestern, southern and northwestern portion of the Planning Area.
Implementation of the General Plan Update will
facilitate new development throughout the Planning
Area. Future development projects, including
modifications to existing buildings, demolition,
grading activities, site excavation, and construction
could potentially result in direct or indirect
disturbance or destruction of historic resources. The
General Plan requires that site specific studies be
conducted when development is proposed.
Previous cultural surveys have identified archaeological sites throughout the General Plan Planning Area. Vacant lands that have not been surveyed may contain buried archaeological resources. Future construction activity on these lands, including grading activity, site excavation, and general construction could potentially result in direct or indirect disturbance or destruction of archaeological resources. Site surveys are required by the City as part of the entitlement process, to assess potential harm to these resources. New development activity, including construction, grading, and other site disturbances in moderate and high sensitivity areas has the potential to impact paleontological resources.
This EIR includes mitigation measures requiring
site specific surveys for development projects.
These mitigation measures will reduce potential
impacts to cultural resources to less than significant
levels.
Alternatives: All the alternatives represent
development scenarios that would impact cultural
resources in a manner similar to the Preferred
Alternative. Alternative 1, because of its reduced
intensities, could have slightly lower impacts. The
mitigation measures provided in this document will
reduce impacts of all alternatives to less than
significant levels.
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GEOLOGY AND SOILS
The General Plan Planning Area is located at the
boundary of the Colorado Desert Province and the
Peninsular Ranges Province. Elevations within the
Planning Area generally range from approximately
190 feet below sea level at the southeastern corner
of the Planning Area, to 1,700 feet above sea level
in the foothills of the Santa Rosa Mountains.
There are seven soil units that have been mapped in the Planning Area. The Whitewater River traverses the northern part of the City. It is the primary drainage in the Coachella Valley, and intermittently drains the surrounding mountains as well as the northern portion of the Valley. The San Andreas Fault trends generally northwest to southeast, approximately 4 miles north of the planning area. As a result, the Planning Area is located in a physical and geographic area that is susceptible to strong seismic activity. Earthquakes can result in impacts ranging from significant property damage to the loss of public services and facilities and the loss of life. The most severe impacts in the La Quinta area would be expected to result from strong ground shaking associated with earthquakes.
Although no active or potential active faults occur
in the Planning Area, geological analyses
conducted for the General Plan indicates that the
Planning Area could experience moderate to very
high ground shaking from earthquakes along the
San Andreas Fault. These levels of ground shaking
have potential to cause moderate to heavy damage,
especially to older and poorly constructed
buildings. Strong ground shaking can also result in
indirect hazards, including slope instability,
liquefaction, settlement, landslides, and flood
inundation.
The soil types found in the City and Sphere exhibit a variety of characteristics, some of which may influence geological hazards, including slope instability, collapsible, compressible, and expansive soils, corrosivity, ground subsidence, and erosion. Soil structure also affects drainage, infiltration, and other hydrological processes. Development at the base of foothills and slopes of the Santa Rosa Mountains may be subject to slope instability such as rockfall, and to a more limited extent landslides, debris flow and rockslide.
The General Plan includes a number of policies and
programs to minimize potential impacts to soils and
geology. This EIR also includes mitigation
measures, ranging from grading specifications to
the requirements for project-specific geotechnical
studies and the proper construction of trenches and
foundations. These mitigation measures will reduce
the impacts associated with geology and soils to
less than significant levels.
Alternatives: All alternatives represent the
construction of new development that would be
subject to the same standards imposed under the
Preferred Alternative. No alternative is considered
preferable as regards impacts associated with
geology and soils.
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HAZARDS AND HAZARDOUS MATERIALS
The General Plan Update Planning Area is near
four major transportation routes commonly used for
transporting hazardous waste. Hazardous waste
cleanup on transportation routes is the
responsibility of various state and federal agencies.
There are no hazardous waste sites in La Quinta or
Sphere of Influence that are listed pursuant to
Section 65962.5(a). The closest listed site is the
Foster-Gardner facility in Coachella, located south
of Avenue 50 between Highway 86 and Highway
111.
The General Plan Update Planning Area is located near two airports, including the Bermuda Dunes Airport and the Jacqueline Cochran Regional Airport. La Quinta is situated at the base of the Santa Rosa Mountains, however, these areas are considered low wildfire zones. The open space and wilderness areas on the western portion of the City are made up primarily of Granitic rock and sparse desert vegetation. Therefore, there is limited vegetation to burn that could cause a major wildfire. The flat urbanized areas of La Quinta are considered very low wildfire areas.
Hazardous materials are highly regulated by
various government agencies, such as Caltrans, the
California Highway Patrol, and the US Department
of Transportation, and cleanup and containment of
these accidents is monitored by these same
agencies. Emergency evacuation and response
plans are already developed in La Quinta to provide
automated notification to residents during an
emergency, including hazardous waste spills.
The General Plan Update provides commercial and light industrial land use designations, particularly the Sphere,that will potentially increase the amount of hazardous materials transported throughout the area. Eastern portions of the La Quinta Planning Area are located within the Jacqueline Cochran Airport Influence Area Zone D and E of the Compatibility Plan. New development within the eastern boundary of the Sphere of Influence will need to abide by Compatibility Plan polices and land use regulations.
Mitigation measures include in this EIR require
analysis of suspected and known hazardous
materials releases; requiring the proper reporting,
storing, transport and disposal of hazardous
materials for all existing and proposed
development; compliance with airport planning
documents; and continued coordination of all
responsible agencies for both everyday
occurrences, and emergency situations. These
mitigation measures will reduce impacts associated
with hazardous materials to less than significant
levels.
Alternatives: All alternatives propose new
development, which would be subject to the same
mitigation measures as the proposed General Plan.
The Alternative 1, which proposes development at
lower intensities, would have a somewhat lower
risk associated with the materials, due to the
reductions in building intensities.
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Existing Conditions Project Impacts Mitigation Measures
HYDROLOGY
Analysis and design of regional flood control
structures is the responsibility of the Coachella
Valley Water District (CVWD). In the Planning
Area, CVWD manages regional facilities, which
collect runoff from areas outside the City, including
surrounding mountains. Planning, maintenance and
construction of improvements for regional facilities
fall within the broad management responsibilities
with which CVWD is charged. Regional facilities
in the Planning Area include the Coachella Valley
Stormwater Channel (Whitewater River), the La
Quinta Evacuation Channel, the Bear Creek
System, the East La Quinta Channel System, Dike
No. 2, Guadalupe Dike, and Dike No. 4.
Zones A or AO in the Planning Area (areas within the 100-year flood plain) occur within the Coachella Valley Stormwater Channel, the La Quinta Evacuation Channel, Bear Creek Channel, and detention basins.
Implementation of the proposed General Plan will
facilitate urban development that will result in an
increase in impervious surfaces, such as roadways,
sidewalks, and parking lots. Water that would have
been re-absorbed into the ground will runoff to
downstream areas. The City and CVWD have
worked pro-actively to protect developed areas in
the City from flood hazards. Currently, with the
exception of some golf courses that serve dual
purpose as stormwater retention areas, no
developed areas in the City are within a FEMA
Special Flood Hazard Zone.
Given that the region is seismically active, the
Planning Area may be susceptible to flooding if
water reservoirs or water retention structures or
facilities should fail. The City and Sphere are
traversed by the Coachella Valley Stormwater
Channel, most of which (in the planning area) has
been improved with slope protection. These have
potential for seismic settlement or liquefaction,
especially in the event of strong ground shaking or
long periods of rain. Earthquakes can also create
seiche conditions within open waterbodies, such as
Lake Cahuilla, canals, reservoirs and catch basins.
The sloshing movement of water within
containment structures can damage them, and water
may overtop, potentially inundating areas down
slope.
Future development within the Planning Area may
be subject to localized flooding risks, especially
where flood hazard mapping is incomplete. The
General Plan includes a range of policies to reduce
these risks, including enforcement of existing
County and City ordinances that address hazards
and floodplain regulations.
This EIR imposes mitigation measures associated
with hydrology which would focus on the
implementation of the Master Plans of Drainage,
and the control and management of runoff created
by new development. These mitigation measures
will assure that impacts associated with hydrology
are reduced to less than significant levels.
Alternatives: Alternative 1 would result in
marginally lower impacts, due to a reduction in
development densities. All alternatives would
implement Master Plan and site-specific mitigation
measures, and would therefore result in less than
significant impacts.
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WATER RESOURCES/QUALITY
The Coachella Valley and the Planning Area are
within the Colorado River Watershed, which drains
into the Salton Trough.
The Whitewater River Subbasin (also known as the “Indio Subbasin”) encompasses approximately 400 square miles and underlies most of the Coachella Valley. Domestic and irrigation water is provided in the City and most of the Sphere by CVWD. Groundwater is the primary source for these water supplies, which CVWD extracts from the Whitewater River Subbasin by means of a system of deep wells within the region. CVWD data shows that significant increases in total water demand in the Coachella Water Valley occurred during over the decades from 1936 (92,400 acre feet/year (AFY) to 376,000 AFY in 1999. CVWD estimates the annual overdraft for 2010 to be 7,457 acre-feet. Currently CVWD has 21 active wells in the General Plan Area. In addition, there are 6 booster stations and 10 planned or existing reservoirs in the Planning Area. Each reservoir has between 250,000 and 12 million gallons of capacity, with a total storage capacity of all reservoirs of 44.6 million gallons. The existing water demands for the La Quinta Planning Area are estimated to be 32,496 acre-feet per year, consisting of 31,227 acre-feet within City limits and 1,268 acre-feet within the Sphere of Influence.
The build out water demands for the La Quinta
Planning Area are estimated to be 54,467 acre-feet
per year, consisting of 37,783 acre-feet within City
limits and 16,684 acre-feet within the Sphere of
Influence. Build out water demands in the Planning
Area are comprised of 30.6% within the Sphere and
69.3% within City Limits.
CVWD’s 2010 UWMP accounts for new growth and development that is expected to occur within the region including the Planning Area. Section 3.3 of the WSS describes the water demand projections for the La Quinta General Plan Update relative to the water demand projections set forth in the CVWD UWMP. The average per capita water demand for the CVWD Service Area is approximately 482 gallons per capita per day (gpcd) for 2010 and is projected to be 423 gpcd for 2035. The 2010 per capita water demand for the La Quinta Planning Area is approximately 473 gallons per day and is projected to be 361 gpcd in 2035. The water demand estimates for the La Quinta Planning Area for 2010 and 2035 are 2% and 15% more efficient compared to the CVWD estimates. As such, water demands generated by the La Quinta Planning Area are fully captured and accounted for within the CVWD UWMP projections. Therefore, water demand projections proposed by the La Quinta General Plan Update are consistent with the water demand estimates utilized by CVWD.
CVWD expects to have sufficient water supplies to
serve development in the Planning Area through
2035 and beyond by utilizing a combination of
water supply sources and treating surface water
supplies.
Mitigation measures included in this document are
designed to reduce the demand for water, and lower
the amount of water removed from the aquifer.
These mitigation measures include conservation,
use of efficient appliances and landscaping
techniques, and the careful review of site specific
proposals to assure compliance with local and
regional regulations. With implementation of these
mitigation measures, the impacts of build out of the
General Plan on water quality and water resources
will be reduced to less than significant levels.
Alternatives: Alternative 1 would result in
marginally lower impacts, due to a reduction in
development densities. All alternatives would
implement mitigation measures, and would
therefore result in less than significant impacts.
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LAND USE, POPULATION & HOUSING
The 2002 General Plan contains a total of 34,112
acres within City limits, the Sphere of Influence
and Planning Areas 1 and 2. Land use designations
include a variety of residential, commercial, open
space, and public facility development.
Although several land use changes are proposed under the General Plan Update, the Preferred Alternative does not significantly change the overall development pattern for the La Quinta Planning Area. Planning Areas outside of City limits have been reduced to the Sphere of Influence and no longer call out separate Planning Areas 1 and 2, which were part of the 2002 General Plan. Under the proposed General Plan Update similar land use designations have been consolidated to simplify land use descriptions. The La Quinta General Plan Update proposes different land use intensities compared to those set forth under the Riverside County Land Use Plan. As proposed, the La Quinta General Plan Update would result in the development of up to 21,270 residential units, 2.7 million square feet of commercial, and 611,408 square feet of industrial land uses within the Sphere of Influence east of City limits.
Land use designation as set forth under the General Plan Update are consistent with the existing development pattern and land uses within the City. Land use designation and development as proposed are not expected to divide residents, businesses, or existing communities. Rather, the General Plan Update assures continuity between existing development and planned future development by refining land use designations and assigning land uses to vacant lands within City limits. The Sphere of Influence represents the greatest potential for land use conversion, since only 11.5% of the area is currently developed. Under the General Plan Update, the Sphere of Influence is primarily designated for low-density residential development, consisting of 7,378 acres out of the total 8,101.4-acre area. The remaining land use designations include 24.6 acres of medium/high density residential, 285.1 acres of general commercial, 63.8 acres of industrial/light manufacturing, 29.8 acres of major community facilities, and 319.9 acres for street rights-of-way. Although the proposed land use development pattern is consistent with the 2002 General Plan, implementation would result in a substantial change to the existing character within the Sphere of Influence.
The General Plan includes policies and programs
designed to provide buffers between residential and
commercial or industrial land uses, and the City’s
Municipal Code includes standards that require any
non-residential development to appropriately
protect surrounding residential development. The
General Plan Update requires the preparation of a
master plan prior to annexation of this area, which
reflects the character of Vista Santa Rosa.
None required.
Alternatives: The No Project alternative would
have the least impacts on land use, population and
housing.
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MINERAL RESOURCES
The majority of incorporated regions of La Quinta
and the Sphere of Influence are located in MRZ-1,
or areas where adequate information indicates that
no significant mineral deposits are present, or are
likely to occur. Most areas within MRZ-1,
particularly within incorporated La Quinta, are
urbanized and developed. Land designated MRZ-1
in the Sphere of Influence is mostly agricultural
land with small residential subdivisions and large
lot residential.
Lands that fall under the MRZ-3 designation make
up a small portion of La Quinta. These areas are
known to contain mineral deposits, however there
have been no evaluations on the significance of
these resources. The MRZ-3 designation is found
only in the southwestern portion of the City,
including along the Coral Reef Mountains and
within the Cove area. Aside from the development
that already exists within the Cove, the majority of
land in the MRZ-3 zone is designated as open
space. The Open Space designation does not
permit mining activities, and requires the land to be
preserved in its natural state. A small portion of
MRZ-3, located just north of Avenue 60 and west
of Madison, is undeveloped vacant land designated
for low density residential development.
The majority of lands within the City are
developed. Remaining vacant lands include infill
lots, and scattered parcels located primarily within
the Cove area and southwestern portion of the City
Limits, which may develop according to land use
designations proposed by the General Plan Update.
The General Plan Update will also facilitate new development within the Sphere of Influence. The majority of these lands are located within the MRZ-1 designation, or an area determined as having no significant mineral resource deposits. Currently, this area is used for agricultural purposes, and there are no known mineral leases, claims, or prospects located in the Sphere of Influence or vicinity. Implementation of the General Plan Update, will have no impact on mineral resources within the City or Sphere of Influence.
None required.
Alternatives: All alternatives represent similar
levels of development, in areas not considered to
have significant mineral deposits. No impacts will
occur under any alternative.
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Existing Conditions Project Impacts Mitigation Measures
NOISE
The General Plan Update Planning Area enjoys a
moderately quiet noise environment, especially
within residential areas. Primary sources of noise
throughout the City are caused primarily by motor
vehicle traffic on City streets, particularly major
roadways. This includes general operation of cars,
trucks, and bus lines. Other noise generators in the
City include those associated with commercial uses
and construction noise. These noises include
loading dock operations, trucks entering and
leaving commercial centers, and mechanical
equipment, such as fans, motors, and compressors.
The Sphere of Influence consists primarily of
agricultural and vacant lands, and vehicular traffic
is much less than that found throughout the City.
As such, the Sphere of Influence enjoys a quiet
noise environment. Within the eastern Sphere,
noise is generated from periodic flights and general
aviation operations at the Jacqueline Cochran
Regional Airport. The airport is located adjacent to
the eastern boundary of the eastern Sphere, east of
Harrison Street. Within the northern Sphere of
Influence, noise is also generated from occasional
overhead flights associated with the Bermuda
Dunes Airport, which is located two miles
northeast.
Hourly noise levels currently range between 57.7
dBA Leq to 72.9 dBA Leq.
Noise standards in La Quinta allow sensitive land
uses to experience a maximum noise level of 65
dbA CNEL in outdoor living areas (patios,
balconies and rear yards). Many of the roadway
segments exhibit future noise levels greater than 65
dBA CNEL beyond the established right-of-way.
Sensitive land uses, including residential uses, back
up to many of these roads, and may potentially
experience noise levels beyond noise standards.
The noise contours are based upon soft site
conditions, and do not account for noise barriers,
topography, or final roadway grades that may affect
ambient noise levels.
In addition to new residential development,
implementation of the General Plan Update will
facilitate construction of new commercial and
industrial land uses throughout the Planning Area.
With increased commercial and industrial
development, land use compatibility issues may arise
when sensitive land uses are located adjacent to
commercial/industrial areas. All land uses are
required to comply with exterior noise levels set forth
in the City’s Noise Ordinance and General Plan,
however additional mitigation measures to reduce
impacts on sensitive uses. As a result, noise levels in
excess of established noise standards generated from
industrial and commercial uses are expected to be
less than significant with proper mitigation.
The General Plan includes policies and programs to
assure that all future development meets the City’s
noise standards. The mitigation measures in this
EIR include on and off site measures, and the
analysis of development proposals to assure
compliance with acceptable noise levels. The
implementation of these measures will assure that
impacts associated with noise at build out will be
less than significant.
Alternatives: Alternative 1 would both result in
lower noise levels as a result of reduced building
intensities and traffic volumes. Mitigation measures
would be applied to these alternatives as well, and
would result in less than significant impacts.
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POPULATION AND HOUSING
Currently, there are approximately 23,489 dwelling
units within the City, 14,820 of which are occupied.
Assuming an average household population size of
2.53 and full occupancy of all existing dwelling
units, the existing population in La Quinta’s City
limits is estimated to be 59,427.
In the Sphere of Influence, under Riverside
County’s land use designations, there are
approximately 7,173 acres of residentially
designated lands, of which 538 acres are currently
developed. According to Riverside County, the
developed acreage contains an estimated 801
existing low density residential dwelling units.
Based on the persons per household figure of 2.53,
the existing population within the Sphere of
Influence is estimated to be 2,027.
In total, the General Plan Update Planning Area is
estimated to contain an existing population of
61,454.
Within the La Quinta City limits, build out of the
proposed General Plan Update has the potential to
result in the development of an additional 8,114
dwelling units, which could support an additional
20,528 people, assuming an average household
occupancy of 2.53. At General Plan build out, the
population size within city limits is projected to be
79,956, based on full occupancy of the 31,603
dwelling units that are proposed under the General
Plan Update. This represents a 34% increase over
the existing number of dwelling units and the
associated population size.
According to the Southern California Association
of Government’s (SCAG) May 2011 growth
forecasts, it is projected that by 2035 La Quinta’s
permanent population will be 46,297 people, and
there will be 17,948 occupied dwelling units within
the City of La Quinta. SCAG projections assume an
annual growth rate of approximately 0.85%.
In the Sphere of Influence, under the County’s land
use designation, there are approximately 7,175
acres of residentially designated lands. If the
Sphere were to build out under the current County
land use designations, a total of 11,946 residential
units would be developed. The General Plan
Update requires the completion of a master plan for
the eastern Sphere, which could significantly
change the number of units that are developed in
this area. The General Plan Update allows for the
development of up to 21,500 residential dwelling
units, which would result in a built out population
size of 54,396 within the Sphere of Influence. As
proposed, implementation of the General Plan
Update would increase the population within the
Sphere of Influence by 24,174 people or 80% over
the current County land use designations.
The General Plan includes policies and programs to
assure that all future development is consistent with
development patterns in the City currently. This
EIR requires the master planning of the Sphere to
address land use intensities and densities consistent
with the character of the area. With this mitigation,
impacts to population and housing will be less than
significant.
Alternatives: The No Project Alternative and
Alternative 1 would result in lower building
intensities, and therefore lower growth, and would
therefore be less impacting than the Preferred
Alternative.
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Existing Conditions Project Impacts Mitigation Measures
PUBLIC SERVICES AND FACILITIES
The General Plan area is located within the service
boundaries of a wide range of public services and
facilities providers, which are listed below.
Public Schools: Desert Sands Unified School
District, Coachella Valley Unified School
District
Library Services: Riverside County Library
System
Law Enforcement: La Quinta Police
Department/Riverside County Sheriff’s
Department
Fire Protection: La Quinta Fire Department
Electricity: Imperial Irrigation District
Natural Gas: The Gas Company
Domestic Water: Coachella Valley Water
District
Wastewater Collection/Treatment: Coachella
Valley Water District
Solid Waste Management: Burrtec Waste and
Recycling Services, LLC
Build out of the General Plan has the potential to
generate 23,293 students.
General Plan build out will require approximately
the library to have 268,704 volumes to serve the
build out population.
Maintenance of the target ratio of 1 police officer
per 1,000 residents at General Plan build out will
require a total of 134 sworn officers at build out.
The County Fire Department cites thresholds
established in its 1986 Master Plan, which call for
one new fire station per every 2,000 dwelling units
or 3.5 million square feet of commercial
development.
Development facilitated by build out of the General
Plan will result in wastewater generation in the
General Plan and annexation areas of
approximately 7.4 million gallons per day.
Development facilitated by build out of the General
Plan and annexation areas will result in domestic
water demand of approximately 54,467 acre feet.
Build out of the General Plan will result in the
generation of 139,181 tons per year of solid waste.
The build out of the General Plan has the potential
to significantly impact schools, police and fire
services, wastewater treatment and solid waste
facilities without mitigation. The mitigation
measures in this EIR, however, require the
coordination of new development proposals with
affected agencies, the payment of required fees
designed to offset impacts, and the continued
conservation and reduction of the use of resources.
The annexation of lands in the eastern Sphere
would have a negative fiscal impact on the City.
The General Plan includes policies that require both
the preparation of fiscal impact analyses for
annexation proposals, and a Development
Agreement in association with annexation.
These mitigation measures will reduce impacts to
public facilities and services to less than significant
levels.
Alternatives: Alternative 1 would result in lower
intensities of development, and would therefore
reduce impacts associated with public facilities and
services. The same mitigation measures would be
imposed on these alternatives, and impacts would
be less than significant.
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RECREATIONAL RESOURCES
The City owns, operates and maintains numerous
park facilities throughout incorporated areas of the
General Plan Update Planning Area. Within the
City Limits are five mini parks, including
Eisenhower Park, Seasons Park, Saguaro Park,
Desert Pride and Velasco Park. Neighborhood
parks include Fritz Burns Park, Adams Park,
Monticello Park, and Pioneer Park. There are three
community parks in La Quinta including the 16.75-
acre La Quinta Sports Complex, the 18-acre La
Quinta Park, and the 17.5-acre Civic Center
Campus.
The Desert Recreation District provides park
facilities and recreation programs throughout the
Coachella Valley. The District owns and operates
the La Quinta Community Center, and is proposing
a Discovery Center near Lake Cahuilla.
The La Quinta Community Center and Park is
located off Avenida Montezuma, and includes a
6.5-acre park and 5,000 foot community center.
The 6.5-acre park includes ballfields, basketball
courts, playground, picnic tables, barbecues,
restrooms, an outdoor amphitheater, outdoor
exercise facilities, and drinking fountains. The
Community Center includes the La Quinta Fitness
Center, kitchen, and concessions.
Riverside County operates Lake Cahuilla Regional
Park located in southwestern portion of La Quinta.
The Sphere of Influence has no public parks or
other recreational facilities.
The General Plan requires the provision of 5 acres
of parkland for each 1,000 population. Based on
this standard, a population of 79,956 within the
City at build out would require a total of 395 acres
of parkland. Implementation of the General Plan
Update has the potential to result in the
development of approximately 20,699 new
residential units within the Sphere at build out.
Total population within the Sphere is expected to
reach 54,396 residents. At build out the Sphere
would require a total of 272 acres of parkland, if
the Sphere were annexed to the City.
With implementation of required fees for new
development projects, implementation of the
General Plan Update will have less than significant
impacts to existing parks within the City.
None required.
Alternatives: All alternatives would result in
demands for recreational resources, although lower
intensity alternatives would reduce impacts
associated with recreational facilities.
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TRANSPORTATION AND TRAFFIC
The roadway segments analyzed are currently
operating at LOS A, with the exception of three
segments of Washington Street and one segment of
Highway 111 that are operating at LOS B.
During the peak season, all but four of the 37 study
intersections operate at LOS C or better. The
intersection of Washington Street/Highway 111
operates at LOS D, very near LOS C, during the
a.m. peak hour. During the p.m. peak hour, this
intersection operates at a slightly worse delay
during peak season conditions, but remains at LOS
D. The intersection of Avenida Bermudas/Avenue
52 operates at LOS D and very near LOS C, during
the a.m. peak hour. The intersection of Madison
Street/Avenue 50 operates at LOS D during only
the p.m. peak hour.
The majority of the roadway segments are forecast
to operate at acceptable levels of service (V/C
ratios less than or equal to 0.90 or LOS D or better)
The roadway segments identified below are
forecast to operate at an unacceptable LOS (V/C
greater than 0.90) based on assigned roadway
classifications. Three segments are projected to
operate at LOS E and three at LOS F at 2035 build
out.
Washington Street segments between Avenue
42 and Miles Avenue and between Highway
111 and Eisenhower Drive
Madison Street between Avenue 54 and
Airport Boulevard
Harrison Street between Airport Boulevard and
Avenue 58
Of the 37 intersections analyzed, the following four
are not expected to be able to accommodate all the
required build out improvements and therefore
have the potential to be operating at unacceptable
levels of service by 2035 General Plan build out:
Washington Street @ Fred Waring Drive;
Adams Street @ Miles Avenue;
Jefferson Street @ Highway 111;
Madison Street @ Avenue 50.
The mitigation measures included in this EIR focus
on the maintenance of acceptable levels of service
through the adequate ultimate development of the
City’s roadways, and the increase of alternative
transport. Even with mitigation, however, traffic
impacts will remain significant and unavoidable.
Alternatives: The No Project alternative will
represent the greatest reduction in trips, but all
alternatives would have significant and unavoidable
traffic impacts.
Terra Nova/ La Quinta General Plan EIR
Section I. Introduction and Project Description
I-1
LA QUINTA GENERAL PLAN
ENVIRONMENTAL IMPACT REPORT
I. INTRODUCTION AND PROJECT DESCRIPTION
Lead Agency A.
The City of La Quinta is the lead agency responsible for the preparation of this Environmental
Impact Report (EIR). The contact person for the General Plan Update project is Mr. Andrew J.
Mogensen, AICP, Planner. The City’s mailing address is 78-495 Calle Tampico, La Quinta, CA
92253, (760) 777-7125.
Introduction B.
This Environmental Impact Report has been prepared to analyze the potential impacts associated
with the implementation of the City of La Quinta General Plan. Under the California
Environmental Quality Act (CEQA), General Plans and their amendments are considered
“projects” which require thorough analysis in the form of an EIR. Therefore, this EIR is an
integral part of the General Plan development process.
The area addressed in this Environmental Impact Report includes the City’s current corporate
boundary and Sphere of Influence, referred to in this document as the City of La Quinta General
Plan Update Planning Area.
This document has been developed utilizing a broad range of data sources, including City,
County, regional and state information sources. In addition, a number of specialized analyses
were conducted specifically for the General Plan Update. These analyses are cited throughout
this document, and provided in their entirety in the Appendices.
This document incorporates all changes to exhibits and text that were noted in the “Final EIR
Response to Comments” dated November 2012.
Terra Nova/ La Quinta General Plan EIR
Section I. Introduction and Project Description
I-2
Document Organization C.
The range of environmental issues associated with implementation of the General Plan, and
evaluated in this EIR include land use compatibility, traffic and circulation, flooding and
drainage, geotechnical and seismic safety, air quality, and biological and archaeological
resources. Noise impacts, visual resources, the availability of public services and facilities and
socio-economic impacts are also assessed.
Section II of this document describes the City and regional environmental setting and establishes
the context in which the General Plan Update is analyzed. It discusses environmental resources
and constraints, existing regional infrastructure, and identifies existing land use patterns and
natural resources.
Section III provides a comprehensive analysis of existing conditions in the Planning Area,
potential impacts to the physical environment that may occur as a result of the adoption of the
proposed General Plan, and mitigation measures, where necessary, that will reduce the impacts
to the greatest extent possible. Where impacts cannot be reduced to less than significant levels,
the impacts remaining following mitigation are identified and quantified. Section III considers
population, development patterns, modifications to the natural and man-made environment, and
the availability of public services and facilities. A mitigation monitoring and reporting program
is also included in this Section.
The EIR also identifies all CEQA-mandated topics to facilitate long-range planning. These
include short-term use and long-term productivity of the affected environment, and the
irreversible and irretrievable commitment of resources, such as water resources, air quality and
biological resources. It also considers growth inducing and cumulative impacts associated with
adoption of General Plan land uses, and identifies and analyzes possible and appropriate
alternative projects. A list of persons, organizations and documents consulted or referenced in
the EIR are provided in Section IX.
CEQA and Other Requirements D.
This Environmental Impact Report has been prepared in compliance with the California
Environmental Quality Act (CEQA) Statutes (Public Resources Code Section 21000-21177) and
CEQA Guidelines of 2010 (California Code of Regulations Section 15000 et. seq.) as amended.
As stated in CEQA, the adoption of a general plan, or element or amendment thereof, requires
that findings be made regarding the identified significant environmental effects (Title 14,
California Code of Regulations Section 15088). Substantial evidence must be provided to
support the EIR, including an explanation of how impacts have been or will be mitigated.
This EIR is intended for use by decision makers, the general public and other responsible or
interested agencies. It has been developed to serve as an informational and analytical document
to provide an objective evaluation of environmental impacts associated with the proposed
General Plan. This EIR includes mitigation measures that are provided to remove or reduce to
acceptable levels the environmental impacts associated with the build out of the General Plan.
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Section I. Introduction and Project Description
I-3
The mitigation measures and the final EIR shall become part of the project approval, and
therefore an essential part of the General Plan.
A variety of City departments are responsible for review of the General Plan. In addition, a
number of local, state, federal and regional agencies may review and comment on this EIR,
including, but not limited to the California Office of Planning and Research, California
Department of Fish and Game, U.S. Fish and Wildlife Service, Southern California Association
of Governments (SCAG), Coachella Valley Association of Governments, South Coast Air
Quality Management District (SCAQMD), County of Riverside, adjoining cities and utility
providers serving the Planning Area.
This EIR is intended to serve at a Program level. Therefore, additional environmental
documentation, such as negative declarations, mitigated negative declarations and environmental
impact reports may be required for development applications that the City may process in future.
An Initial Study was prepared for this project, as part of the Notice of Preparation (NOP). The
NOP identified a number of issues as having potential to result in significant environmental
impacts. Any issue area identified as having the potential to impact the environment is addressed
in this document.
The Initial Study identified the following environmental issues where no impact is expected.
Therefore, no further discussion of these specific issues is included in this EIR.
Biological Resources: would the project:
e) Conflict with any local policies or ordinances protecting biological resources, such as a
tree preservation policy or ordinance?
Hazards and Hazardous Materials: would the project:
f) For a project within the vicinity of a private airstrip, would the project result in a safety
hazard for people residing or working in the project area?
Noise: would this project:
f) For a project within the vicinity of a private airstrip, would the project expose people
residing or working in the project area to excessive noise levels?
Population and Housing: would the project:
b) Displace substantial numbers of existing housing, necessitating the construction of
replacement housing elsewhere?
c) Displace substantial numbers of people, necessitating the construction of replacement
housing elsewhere?
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Section I. Introduction and Project Description
I-4
Project Location and Description E.
1. Project Location
The City of La Quinta General Plan Update Planning Area encompasses approximately 48.3
square miles situated in the south central portion of the Coachella Valley, in central Riverside
County, California (please see Error! Reference source not found., Regional Location Map).
The Planning Area is generally bounded on the north by lands south of Hidden River Road, on
the south by Avenue 64, on the west and southwest by the Santa Rosa Mountains, and on the east
by Harrison Street (please see Error! Reference source not found., Vicinity Map). The General
Plan Update Planning Area is comprised of lands within the City’s corporate limits, as well as
the City’s Sphere of Influence.
City Limits
City Limits
The Planning Area is located within the following US Geological Survey (USGS) Quadrangles:
La Quinta, Indio, Palm Desert, and Valerie, California.
The incorporated limits of the City of La Quinta encompass 35.7± square miles, which are
developed for a range of residential, resort and resort residential, commercial and open space
uses.
Lands within the City limits may also be described as follows:
Portions of Section 25 and all of Section 36, Township 5 South, Range 6 East; Sections
1,12,13,24, and 25, Township 6 South, Range 6 East; portions of Section 17 18, 19, 20,28,29,
and 30, and all of Sections 31 and 32, Township 5 South, Range 7 East; portions of Section
26, 35 and all of Sections 4, 5, 6,7,8,9,10,15,16,17,18, 19, 29, 21, 22, 27, 28, 29, 30, 33 and
34, Township 6 South, Range 7 East; Sections 4 and 5, Township 7 South, Range 7 East of
the San Bernardino Baseline and Meridian.
Sphere of Influence
The Sphere areas in the Planning Area, total 12.6± square miles. One of these occurs to the north
of the City’s corporate limits, and the other to the east of the City’s corporate limits. Lands
included in the City’s Sphere are those identified by the Local Agency Formation Commission
(LAFCo) as being a logical extension of the City in the long term. Only if these lands are
annexed will the City have jurisdiction over their development. All lands in the Sphere currently
fall under the jurisdiction of the County of Riverside.
The northern Sphere area is located generally north of Fred Waring Drive and east of
Washington Street, extending to Adams Street. This area is partially developed, and consists of
scattered residential development and commercial nurseries. The eastern Sphere is generally
located east of Monroe Street to Harrison Street, between Avenue 52 and Avenue 62. These
lands are primarily comprised of agriculture, lower density residential uses, and limited
commercial development.
Terra Nova/ La Quinta General Plan EIR
Section I. Introduction and Project Description
I-5
The Sphere of Influence of the City of La Quinta may also be described as follows:
Portions of Section 18, Township 5 South, Range 7 East; and portions of Section 12, 13, 26
and 35 and all of 11, 14, 23, 24, 25, and 36, of Township 6 South, Range 7 East; all of
Section 19, 30, 31 of Township 6 South, Range 8 East of the San Bernardino Baseline
Meridian.
Terra Nova/ La Quinta General Plan EIR
Section I. Introduction and Project Description
I-9
2. Project Description
The purpose of this EIR is to assess the environmental constraints and opportunities associated
with the adoption and implementation of the proposed La Quinta General Plan Update, and
evaluate the impacts of build out of the General Plan Land Use Map (please see Exhibit I-5). The
EIR summarizes the land use designations and the major goals and policies established in the
General Plan. It utilizes a range of technical data, which has served as the basis for evaluating a
variety of environmental issues relevant to the City and its Sphere.
Environmental issues considered in this EIR include but are not limited to the following: land
use compatibility, traffic and circulation, flooding and hydrology, geotechnical and seismic
safety, biological and archaeological resources, and noise impacts. In addition, the EIR considers
the availability of public services and facilities, as well as socio-economic impacts associated
with General Plan implementation.
These issues are addressed on approximately 30,957 acres (48.3± square miles) encompassed
within the proposed General Plan Update Planning Area boundaries. Of these, 22,855.5± acres
(35.7± square miles) are within the City limits, and 8,101.4± acres (12.6± square miles) acres are
within the two Sphere areas. Hereinafter, the area addressed under the proposed project is also
referred to as the “General Plan area” or the “Planning Area”.
The General Plan update process has been ongoing over the past 24 months, during which time
the City has solicited the feedback of community members to consider the community’s overall
and specific goals. The City has held a series of public workshops, City Council meetings, and
Planning Commission meetings to consider significant community issues.
The City has conducted a detailed assessment of existing land use designations, and has modified
land use designations for application to lands in the Planning Area. The proposed General Plan
land use designations consolidate previously used designations to implement the proposed
General Plan Update within the City and its Sphere. Proposed Land Use Designations are shown
in Table I-3.
The proposed Planning Area represents an overall reduction in acreage from the 2002 General
Plan, as a result of substantial modifications in the Planning Area boundaries. The 2002 General
Plan encompasses 53,498 acres in its Planning Area, whose boundaries include the City
corporate limits, lands in the City’s Sphere. Approximately 31,360 acres contiguous with the
City’s Sphere were included in the 2002 General Plan planning area, but are not included in the
proposed General Plan Update. The proposed General Plan Planning Area represents a decrease
of 22,541 acres, or 42.9 percent from the 2002 General Plan.
As previously noted, the Sphere of Influence areas have been determined by LAFCO to be a
logical extension of the City’s boundaries over the long term. General Plan land use designations
that have been assigned to lands in the Sphere areas are consistent with those in the 2002 General
Plan, and will remain in effect upon adoption of the General Plan Update. These lands are
analyzed in this EIR.
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Section I. Introduction and Project Description
I-10
Existing Land Use
Currently, the City is governed by the City of La Quinta General Plan adopted on March 20,
2002 (“2002 General Plan”). As previously noted, lands within the 2002 General Plan planning
area include those within the City of La Quinta corporate limits as well as two Sphere of
Influence areas and two additional planning areas outside the Sphere (Planning Area 1 and
Planning Area 2). The 2002 General Plan Land Use Map (please see Error! Reference source
not found.), shows the Planning Area boundaries and land use designations.
The proposed General Plan Planning Area retains the same general boundaries of the
incorporated limits, although some changes have occurred due to annexations subsequent to the
adoption of the 2002 General Plan. The proposed Planning Area includes two Sphere areas,
further discussed below. The following describes existing uses within the City limits and the two
proposed Sphere areas, as well as the 2002 General Plan land use allocation.
City of La Quinta Corporate Limits
The current city limits are generally bounded on the west by Washington Street and the Santa
Rosa Mountains, on the north by lands south of Hovley Lane East, on the east by Jefferson Street
and Monroe Street, and on the south by Avenue 62 and Avenue 64. Topographically, the City is
situated on a flat valley floor surrounded by low mountains, foothills and alluvial fans
characteristic of the desert environment. The valley floor is the site of most of the City’s
developed areas, while surrounding mountains and foothills have been designated and are
retained as open space. The City has historically contained large areas of agriculture on the
valley floor, but this has changed in recent years with increased urbanization. Development
within the City limits is now primarily residential, commercial and resort oriented.
Current Land Use Designations in the City
As is typical of other low density residential and resort developments in the Coachella Valley,
the 2002 General Plan applies residential land use designations in the City ranging from Very
Low Density to High Density. Low Density residential is the predominant residential
designation, comprising 76% of all residential lands in the City. These include the numerous golf
course communities for which La Quinta is well known. Approximately 17% of residential lands
in the City are currently designated Medium Density Residential, which is primarily found in the
Cove community as well as near Highway 111 in the northern incorporated area. Lands
designated for High Density Residential comprise only 1% of residential lands. These are
generally found north of Avenue 48, between Adams Street and Dune Palms Road, and in the far
northwest corner of the City along Washington Street.
The 2002 General Plan designates approximately 6% of lands in the City for commercial uses,
including Mixed/Regional Commercial, Community Commercial, Neighborhood Commercial,
Commercial Park, Office, Tourist Commercial, and Village Commercial. Of these, the most
prevalent are Mixed/Regional Commercial, which accounts for 33% of commercial lands, and
Tourist Commercial at 29%. Lands designated for commercial and office uses are principally
within the Village area, and along Washington Street, Highway 111, Jefferson Street, and
Monroe Street. Under the 2002 General Plan, there are no lands designated for Industrial uses
within the City limits.
Terra Nova/ La Quinta General Plan EIR
Section I. Introduction and Project Description
I-11
Lands designated for recreational and open spaces include Parks, Open Space, Golf Course Open
Space and Watercourse/Flood Control. These land use designations comprise a total of 10,948
acres, or 53%, of the 2002 General Plan land use plan. These designations occur throughout the
City, and correspond to existing uses of these types. The General Plan also allocates limited
lands (approximately 191 acres, or less than 1%) for Major Community Facilities within the City
limits.
Existing Land Uses in the City
The City’s geographic and topographical setting has significantly influenced land use patterns.
The City is bordered by the Santa Rosa Mountains to the west and south, and development in the
City has therefore occurred along the foothills and on the valley floor to the east and north of
these landforms. The City is also served by a network of regional and local roadways. The
backbone system is provided by U.S. Interstate 10, Highway 111 and State Highway 86. I-10 is a
generally east to west roadway that occurs north of the planning area, and provides major inter-
city connection between Valley communities as well as to Los Angeles to the west and Arizona
to the east. Highway 111 runs generally northwest to southeast through the northern portion of
the City. It serves as an intra-regional corridor in the Coachella Valley. State Highway 86 is a
northwest to southeast trending roadway that provides access to communities southeast of the
City along the Salton Sea as well as to Imperial County.
As might be expected given the land use designations described above, much of the existing
development in the City is comprised of single-family residences at lower densities (up to four
units per acre), with typically small, single-family detached units. Master-planned subdivisions
and golf course communities are characteristic of many valley cities, including La Quinta. These
lower density residential developments occur throughout the City. Areas of medium to higher
density residential development are generally limited to the northern portion of the Cove
community, as well as in the northern portion of the City. Lands within the City designated for
residential uses have for the most part built out or are currently under development.
The City contains a variety of commercial uses, many of which are clustered along Highway 111
in the northern part of the City, as well as within the Village area. Along Highway 111,
commercial uses include major retail centers with a variety of anchor tenants. This area also
contains “big box” retail centers, including Walmart Supercenter, Costco, Home Depot, Lowe’s,
Target and Kohl’s, along with small shops, coffee houses, restaurants, banks, and service
stations. Within the Village, there are a variety of small boutique-type shops, art galleries,
restaurants and cafes. Smaller, neighborhood scale commercial development which includes
retail and office/professional uses, are located adjacent to existing neighborhoods throughout the
City.
The City is located in a region renowned for resorts, and itself contains several hotel and resort
properties. Among the most notable of is the La Quinta Resort, located on Eisenhower Road,
north of the Cove community. Dating from the 1920’s, the resort, which includes historic
structures and grounds, offers amenities including a variety of accommodations as well as
recreational amenities such as tennis, swimming and is affiliated with five golf courses,
including three PGA West courses.
Terra Nova/ La Quinta General Plan EIR
Section I. Introduction and Project Description
I-12
There are a wide variety of recreational and open space uses, including City and County parks,
located throughout the City. In addition to the golf courses described above, the City is home to
numerous other public and private courses. The City is bordered to the west and south by
foothills and mountain slopes of the Santa Rosa Mountains, which encompass large areas of
open space within and adjacent to the City.
City of La Quinta Sphere of Influence
As has been described above, the proposed General Plan includes two Sphere areas: the northern
Sphere and the eastern Sphere. The northern Sphere is generally bounded on the north by lands
south of Darby Lane, on the west by Washington Street, on the south by lands north of Fred
Waring Drive, and on the east by Adams Street. The eastern Sphere is generally bounded on the
north by Avenue 52 and Airport Boulevard, on the west by Van Buren Street and Harrison
Street, on the south by Avenue 62, and on the east by Monroe Street.
Current Land Use Designations in the Sphere of Influence
The land use designation within the northern Sphere is Low Density Residential. Within the
eastern Sphere, Low Density Residential is the predominant designation, occupying roughly 90%
of these lands. Other designations apply to lands on the perimeter of this Sphere, with limited
areas of Medium High Density Residential and Neighborhood Commercial along Monroe Street,
a small parcel of General Commercial along Van Buren Street, an approximately 2 mile north-to-
south strip of General Commercial designation along Harrison Street, and limited Industrial
lands near the intersection of Airport Boulevard and Harrison Street.
Current Land Uses in the Sphere of Influence
The northern Sphere contains a mix of single-family residential development and some
remaining commercial nurseries. The eastern Sphere is comprised of agricultural lands, single-
family residential development, as well as large lot residential areas, small nurseries and vacant
lands.
Surrounding Land Uses
The City of La Quinta is surrounded by the cities of Palm Desert, Indian Wells, Indio, Coachella,
and the County of Riverside. To the north, surrounding lands are within the jurisdictions of Palm
Desert, Indian Wells, and a small portion of unincorporated Riverside County. The land uses are
comparable to those in the northern portion of La Quinta, with low-density residential
neighborhoods, commercial uses, and entertainment facilities. The Indian Wells Tennis Garden
is located immediately west of Washington Street in Indian Wells. It is a 55-acre tennis and
entertainment facility with a year-round, world-class tennis club and 16,000 seat stadium.
To the northeast and east are the cities of Indio and Coachella, which are characterized primarily
by commercial and residential uses. There are several large commercial centers along Highway
111 in the City of Indio. Residential developments in Indio and Coachella are generally open
neighborhood developments such as those found in northern areas of La Quinta, in contrast to
private gated communities more characteristic of those found in southern La Quinta.
There are two unincorporated communities east of La Quinta: Thermal and Vista Santa Rosa.
The Vista Santa Rosa Community is a County-recognized community of interest, extending from
Terra Nova/ La Quinta General Plan EIR
Section I. Introduction and Project Description
I-13
Avenue 50 on the north, to Monroe Street on the west, to State Route 86 (Harrison Street) on the
east, and south to Avenue 66. Land uses in Vista Santa Rosa include farming, rural residential,
equestrian activities and polo facilities.
Land uses in Thermal include residential and commercial development, as well as light industrial
uses associated with agricultural production. The Jacqueline Cochran Regional Airport is
immediately east of the La Quinta Sphere of Influence within the westerly portion of Thermal.
To the east and south of the La Quinta Planning Area are lands within unincorporated Riverside
County as well as areas subject to Native American Tribal jurisdiction. Land uses in these areas
are primarily agriculture, scattered single-family residential, and open space.
Lands to the west are primarily within the Santa Rosa Mountains that lie within the County of
Riverside and are designated for open space. The Santa Rosa Mountains rise in sharp relief from
the valley floor, and provide a visually dramatic and scenic backdrop against which the City and
the region are set.
Terra Nova/ La Quinta General Plan EIR
Section I. Introduction and Project Description
I-15
Statistical Summary: General Plan Land Use F.
The Planning Area of the General Plan Update includes approximately 22,855 acres of lands
within the City’s corporate limits, and 8,101 acres within the City’s Sphere, which are the subject
of this analysis. The various land use scenarios associated with development intensities and types
are shown on the General Plan land use maps presented herein.
The recommended project alternative is represented by the Preferred Alternative land use
scenario, which is considered in the main body of the EIR. The Preferred Alternative land use
map is shown in Section III, and the statistical summaries associated with this map are shown in
Table I-1 and Table I-2, below. In Table I-3, the preferred land use designations are defined and
appropriate development types shown categorically. It is important to note that because of the
reduction in the Planning Area from the 2002 General Plan, the General Plan Update results in a
reduction in acreage in most land use categories.
Section V of this EIR provides an analysis of three other land use alternatives. These include the
No Project Alternative, which implements the 2002 General Plan; Alternative 1 and Alternative
2.
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Section I. Introduction and Project Description
I-16
Table I-1
Preferred Alternative General Plan Update
Land Use Acreage Summary
Land Use Designation
# Acres
City
Limits
% of
City
Limits
# Acres
Sphere
% of
Sphere
LDR Low Density Residential
(0-4 du/gross acre)1,3 5,589.7 24.4% 7,378.1 91.1%
M/HDR Medium-High Density Residential
(0-16 du/gross acre)2,3 1,666.0 7.3% 24.6 0.3%
Residential Subtotal 7,255.7 31.7% 7,402.7 91.4%
GC General Commercial 569.6 2.5% 285.1 3.5%
TC Tourist Commercial 345.5 1.5% 0 0.0%
VC Village Commercial 90.0 0.4% 0 0.0%
Commercial Subtotal4 1,005.1 4.4% 285.1 3.5%
I/LM Industrial/Lgt. Mfg. 0 0.0% 63.8 0.8%
Industrial/Light Manufacturing Subtotal4 0 0.0% 63.8 0.8%
Major Community Facilities 446.5 2.0% 29.8 0.4%
Open Space- Natural 6,933.3 30.3% 0.0 0.0%
Open Space- Recreation 5,259.2 23.0% 0.0 0.0%
Street Rights-of-Way 1,955.7 8.6% 319.9 3.9%
Other Land Uses Subtotal 14,594.7 63.9% 349.7 4.3%
TOTAL 22,855.5 100.0% 8,101.4 100.0%
1Includes single-family attached and detached housing units.
2Includes single-family attached and detached and multi-family housing units. 3Future residential development is assumed to occur at 75% of the maximum density permitted. 4Assumes 22% lot coverage for commercial and industrial development. Assumes 70% of TC and VC developed
as commercial.
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Section I. Introduction and Project Description
I-17
Table I-2
General Plan Update
Build Out Summary: City Limits
Land Use Designation Developed Vacant Total Existing
Units
Potential
Units
Total Units
Low Density Residential 4,006.0 1,583.7 5,589.7 20,834 4,752 25,586
Medium/High
Density Residential
1,292.4 373.6 1,666.0 2,655 3,362 6,017
Residential Subtotal 5,298.4 1.957.3 7,255.7 23,489 8,114 31,603
Existing SF Potential SF Total SF
General Commercial 385.6 184.0 569.6 3,695,282 1,763,309 5,458,591
Tourist Commercial 206.6 138.9 345.5 1,979,889 1,331,106 3,310,996
Village Commercial 77.1 12.9 90.0 738,865 123,623 862,488
Commercial Subtotal 669.3 335.8 1,005.1 6,414,036 3,218,039 9,632,074
Major Community Facilities 252.7 193.8 446.5
Open Space - Natural 2,171.6 4,761.7 6,933.3
Open Space - Recreation 4,392.2 867.0 5,259.2
Street Rights-of-Way 1,764.6 191.1 1,955.7
Grand Total 14,548.8 8,306.7 22,855.5
Table I-3
General Plan Update
Build Out Summary: Sphere of Influence
Land Use Designation Developed Vacant Total Existing
Units
Potential
Units
Total Units
Low Density Residential 551.5 6,826.6 7,378.1 801 20,480 21,281
Medium/High
Density Residential
0.2 24.4 24.6 - 219 219
Subtotal 551.7 6,851.0 7,402.7 801 20,699 21,500
Existing SF Potential SF Total SF
General Commercial 28.6 256.6 285.1 273,760 2,458,797 2,732,557
Industrial/Lgt. Mfg. 0 63.8 63.8 - 611,408 611,408
Major Community Facilities 28.17 1.61 29.8
Street Rights-of-Way 319.93 0 319.9
Grand Total 928.4 7,173.0 8,101.4
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Section I. Introduction and Project Description
I-18
Table I-4
General Plan Update
Build Out Summary: Entire Planning Area
Land Use Designation Developed Vacant Total Existing
Units
Potential
Units
Total Units
Low Density Residential1,3 4,557.5 8,410.3 12,967.8 21,635 25,232 46,867
Medium/High Density2,3
Residential
1,292.6 398.0 1,690.6 2,655 3,582 6,236
Total 5,850.1 8,808.3 14,658.4 24,290 28,814 53,103
Existing SF Potential SF Total SF
General Commercial 414.2 440.6 854.7 3,969,042 4,222,106 8,191,148
Tourist Commercial 206.6 138.9 345.5 1,979,889 1,331,106 3,310,996
Village Commercial 77.1 12.9 90.0 738,865 123,623 862,488
Total4 697.9 592.4 1,290.2 6,687,796 5,676,835 12,364,631
Industrial/Lgt. Mfg. 0.0 63.8 63.8 - 611,408 611,408
Major Community Facilities 280.9 195.4 476.3
Open Space - Natural 2,171.6 4,761.7 6,933.3
Open Space - Recreation 4,392.2 867.0 5,259.2
Street Rights-of-Way 2,084.5 191.1 2,275.6
Grand Total 15,477.2 15,479.7 30,956.9
1 Includes single-family attached and detached housing units. 2 Includes single-family attached and detached and multi-family housing units. 3 Future residential development is assumed to occur at 75% of the maximum density permitted. 4 Assumes 22% lot coverage for commercial and industrial development. Assumes 70% of TC and VC developed as
commercial.
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Section I. Introduction and Project Description
I-19
Table I-5
City of La Quinta General Plan
Proposed Land Use Designations
Land Use Designation
(Density)
Purpose of Land Use
Residential Land Uses
Low Density Residential,
(LDR)
(0-4 dwelling unit per gross
acres)
This land use designation is appropriate for single family
residential development, whether attached or detached. The
density of individual parcels is further refined in the Zoning
Ordinance. These lands are typically developed as
subdivisions, country club developments, or master planned
communities. On lands used for equestrian purposes, lots
must be a minimum of one acre. Clustered housing projects
(including condominiums), providing common area open
space, appropriately scaled commercial development serving
the project or amenities are also appropriate under this
designation, with the approval of a Specific Plan. In the
Sphere of Influence, the Low Density Residential designation
is applied as a temporary designation, in anticipation of the
preparation of a Master Plan for the area
Medium/High
Density Residential, (M/HDR)
(0-16 dwelling units per gross
acres)
The Medium/High Density designation is designed to
accommodate a broad range of residential land uses,
including small-lot subdivisions, duplex, condominium and
apartment projects. The density of individual parcels is
further refined in the Zoning Ordinance. Specific Plans may
be appropriate for clustered development in the lower density
zones, but are not required. Uses that may be appropriate with
the approval of a Conditional Use Permit include mobile
home parks and subdivisions and bed and breakfast facilities.
Small retail stores that provide neighborhood conveniences,
are less than 5,000 square feet, and on parcels of up to one
acre, may be allowed with approval of a Conditional Use
Permit.
Terra Nova/ La Quinta General Plan EIR
Section I. Introduction and Project Description
I-20
Table I-5
City of La Quinta General Plan
Proposed Land Use Designations
Land Use Designation
(Density)
Purpose of Land Use
Commercial Land Uses
General Commercial (GC) This land use designation applies to the majority of
commercial land in the City. The full range of commercial
uses can occur within this designation, ranging from
supermarkets and drugstores in a neighborhood shopping
center, to major national retailers in large buildings. General
Commercial uses also include professional offices, service
businesses, restaurants, hotels or motels, research and
development and warehousing or similar low impact quasi-
industrial projects. Mixed use development is also appropriate
in this designation. Mixed use projects can include vertical
mixed use – where retail occurs on the ground floor, with
residential units above; horizontal mixed use – where retail/
office uses and higher density residential occur next to each
other, and are integrated through pedestrian connections and
common areas; or mixed use added to existing commercial
development – where the residential project abuts or wraps
around an existing commercial development.
Tourist Commercial (TC) This land use designation is specifically geared to tourism-
related land uses, such as resort hotels, hotels and motels, and
resort commercial development, such as conference centers,
restaurants, resort-supporting retail and services (including
day spas and similar personal services). Time share, fractional
ownership or similar projects may also be appropriate in this
designation, with the approval of a Conditional Use Permit.
Village Commercial (VC) The Village Commercial designation applies specifically to
the traditional commercial core of the City, and allows
specialty retail – such as boutiques and art galleries – as well
as restaurants, professional offices and services, and hotels.
Apartments, condominiums and live-work space is also
appropriate in this designation. As established in Policy LU-
7.1, mixed use development is allowed in this designation.
Mixed use projects can include vertical or horizontal
combinations of land uses that are integrated through
pedestrian connections and common areas; or can be
residential units added to existing commercial development.
Terra Nova/ La Quinta General Plan EIR
Section I. Introduction and Project Description
I-21
Table I-5
City of La Quinta General Plan
Proposed Land Use Designations
Land Use Designation
(Density)
Purpose of Land Use
Industrial Land Uses
Industrial/Light
Manufacturing (I/LM)
This land use designation applies only to land currently
located in the Sphere of Influence. Therefore, this land use
designation would only become applicable if the designated
lands are annexed into the City. Appropriate land uses include
business parks; value-added non-polluting industrial uses
operating entirely within existing buildings; airport and
aircraft related businesses; warehousing and distribution; and
light manufacturing. Outdoor storage as an ancillary use
when a structure is the primary use on the property can be
permitted entirely screened from public view. Commercial
retail and office uses that support industrial projects are also
appropriate. With the approval of a Conditional Use Permit,
more intense industrial uses, including appliance and
furniture manufacturing, metal product manufacturing and
transportation equipment manufacturing may be appropriate.
All projects proposed within this designation will be
compatible with surrounding land uses or land use
designations, and will mitigate their environmental impacts to
less than significant levels.
Other Land Uses
Major Community Facilities This land use designation has been assigned to existing or
planned municipal, educational or public facilities, such as
City and School District facilities and buildings, utility
facilities and buildings, fire stations and similar uses.
Open Space-Natural (OS-N) This land use designation is applied to areas of natural open
space, whether owned by private parties or public entities.
With the exception of trail or trailhead development, little
development is permitted in this designation. Ephemeral
streams, man made flood control channels and the Coachella
Valley Stormwater Channel are designated Natural Open
Space. Lands purchased by conservation organizations for the
Coachella Valley Multiple Species Habitat Conservation Plan
can be included in this designation.
Open Space-Recreation
(OS-R)
The Recreational Open Space designation applies to parks,
recreation facilities (such as driving ranges, club houses and
athletic facilities), public and private golf courses, and public
parking lots.
Terra Nova/ La Quinta General Plan EIR
Section I. Introduction and Project Description
I-22
Residential Land Uses
Under the Preferred Alternative, a total of 7,255.7 acres of land are allocated to residential uses
in the City’s corporate limits, and 7,402.7 acres in the Sphere areas, for a total of 14,658.4 acres
throughout the Planning Area. There are currently 23,489 dwelling units in the incorporated City
and 801 in the Sphere. The estimate of future build out units in the Planning Area included in
this document is based on an assumption that 75% of the maximum densities permitted will be
developed. The 8,808 acres of vacant lands designated for residential uses under the Preferred
Alternative would therefore accommodate an additional 28,813 dwelling units. Of these, 8,114
would occur in the City limits and 20,699 within the Sphere areas.
At build out, the Planning Area is expected to generate a total of approximately 53,103 dwelling
units, including both existing and potential units. This compares with 78,952 units under the
2002 General Plan. The proposed General Plan therefore provides for build out of 25,849 fewer
dwelling units, or a decrease of 32.7% from the 2002 General Plan. Therefore, the proposed
General Plan represents a less intense development scenario than does the 2002 General Plan.
Commercial Land Uses
Under the Preferred Alternative of the General Plan Update, approximately 1,290 acres are
designated for commercial development, including General, Tourist and Village Commercial
uses in the City and Sphere. This compares with approximately 1,997 acres for all commercial
designations under the 2002 General Plan. Therefore, under the General Plan Update, the
Preferred Alternative will result in a decrease of 707 acres of lands allocated for commercial
development, which is 35.4% less than the 2002 General Plan.
To estimate future build out square footage of commercial units in the General Plan Update
Planning area, it is assumed that commercial lands will build out with 22% lot coverage,
including buildings and other ancillary structures. For Village and Tourist Commercial lands, it
is assumed that 70% of development will be commercial uses.1 Based on this assumption, the
1,290 acres designated for commercial uses will result in 12,364,631 square feet of commercial
space. This compares to 19,137,651 square feet under the 2002 General Plan. Therefore, The
General Plan Update proposed a 35.4% decrease compared to the 2002 General Plan for
commercial uses.
The General Plan proposes the largest concentrations of General Commercial lands within City
Limits along Highway 111, with smaller clusters along Monroe Street and Van Buren Street, and
an approximately 2-mile long strip along Harrison Street in the eastern Sphere. There are also
smaller areas designated for General Commercial use scattered through the City and Sphere
areas, which are expected to develop as neighborhood scale retail and office uses. Tourist
Commercial lands also occur throughout the Planning Area, corresponding with existing resort
areas. Lands designated Village Commercial are located in The Village area of La Quinta.
1 The proposed General Plan Update provides for mixed use residential as a component of General Commercial,
Tourist Commercial and Village Commercial. The potential for residential development in these designations
cannot be currently quantified, given that development standards and location will be determined in the Zoning
Ordinance. Therefore, these units have not been included in build out calculations.
Terra Nova/ La Quinta General Plan EIR
Section I. Introduction and Project Description
I-23
Industrial/Light Manufacturing
The 2002 General Plan allocates 1,947 acres to Industrial uses; it assumes a lot coverage of 34%,
and provides for development of 28,835,849 square feet of industrial space. By comparison, the
Preferred Alternative allocates 63.8 acres to lands designated Industrial/Light Manufacturing,
which occur entirely within the eastern Sphere. The proposed General Plan assumes lot coverage
for industrial uses of 22%, and provides for approximately 611,408 square feet of
Industrial/Light Manufacturing uses at build out. This represents a reduction of approximately
98% from the 2002 General Plan. This reduction is primarily due to two factors. First, the
reduction in lot coverage assumed for Industrial development (22% under the proposed General
Plan versus 34% under the 2002 General Plan); this factor lowers the density and total square
footage expected to be built out on these lands. Secondly, the planning area boundaries are
substantially different under the proposed General Plan, and no longer include lands to the east in
proximity to the Jacqueline Cochran Regional Airport, where most of the industrial uses were
planned under the 2002 General Plan.
Major Community Facilities
The 2002 General Plan provides for approximately 299 acres for Major Community Facilities.
The proposed General Plan provides for 476 acres of lands designated “Major Community
Facilities”, which includes public service facilities, as described above, as well as other public
and quasi-public facilities. Therefore, the proposed General Plan would provide approximately
59% more land for Major Community Facilities uses than does the 2002 General Plan. This
increase is primarily due to additional lands having been designated for public purposes by the
City over the past ten years.
Open Space
Under the 2002 General Plan, 14,120 acres are allocated for Open Space uses, including parks,
golf courses, watercourses, floodways and mountainous areas. The Preferred Alternative
proposes approximately 12,193 acres, a decrease of 1,927 acres, or 13.6% less than the 2002
General Plan. This is primarily due to changes to the planning area boundaries. Open Space
lands south of Avenue 64 that were included in the 2002 General Plan planning area are
excluded from the Proposed General Plan Update Planning Area.
Other Land Uses
Street Rights-of-Way
The proposed General Plan allocates lands for Street Rights-of-Way to ensure adequate provision
for build out of a circulation network to serve future development. The 2002 General Plan did
not specify lands allocated for this use. The Proposed General Plan allocates 2,275.6 acres for
Street Rights-of-Way.
Terra Nova/La Quinta General Plan EIR
Section II. Regional Environmental Setting
II-1
LA QUINTA GENERAL PLAN
ENVIRONMENTAL IMPACT REPORT
REGIONAL ENVIRONMENTAL SETTING II.
Introduction
This Section of the EIR presents the regional and local setting of the General Plan Update, and
sets the stage for the analysis provided in Section III. The environment in which La Quinta is
located is characterized to give the reader a broad description of the issues that influence the City
and its General Plan Update.
Aesthetics A.
The City of La Quinta is located within the Salton Trough, which is a low-lying area that was
once covered by ancient Lake Cahuilla. The topography of the region progresses from the flat
desert floor, where La Quinta is located, to the top of dramatic mountaintops that rise over
10,000 feet. The contrast between the flat desert landscape and the mountain peaks surrounding
it provides views and picturesque landscapes for residents and visitors.
La Quinta is located along the eastern slope of the Santa Rosa Mountains. The Santa Rosa
Mountains are the southern branch of the San Jacinto Mountains. Within these two mountain
ranges is the Santa Rosa and San Jacinto Mountains National Monument. The Monument was
created in 2000, in part to preserve the unique biodiversity within the region. The tallest
mountain within this range is Mt. San Jacinto, which rises to an elevation of 10,804 feet. Mt. San
Jacinto is the furthest north peak of the San Jacinto Mountains, and is only visible from the
eastern portion of La Quinta, away from the foothills at the Valley margins.
The Santa Rosa Mountains form a dramatic backdrop to the city’s western boundary. Toro Peak
is the tallest mountain in the Santa Rosa Mountains, rising to 8,717 feet. Closer yet, although
much lower, are the foothills of the Santa Rosa Mountains, known as the Coral Reef Mountains.
The Coral Reef Mountains are located within the La Quinta city boundary and rise about 1,000
feet above sea level. As their name implies, the Coral Reef Mountains look like giant coral reefs
springing up from the valley floor. The Cove area of the City is situated within these mountains.
Terra Nova/La Quinta General Plan EIR
Section II. Regional Environmental Setting
II-2
Other mountains providing a visual resource for La Quinta include the San Bernardino
Mountains to the northwest, Little San Bernardino Mountains to the north, and the Indio Hills to
the northeast and east.
The General Plan Update will result in growth and development throughout incorporated La
Quinta and the Sphere of Influence, which may cause impacts to existing aesthetic and visual
resources. A detailed analysis of visual impacts is addressed in Section III of this EIR.
Agriculture Resources B.
Agriculture has historically been a major economic sector in the eastern portion of the Coachella
Valley, including La Quinta. Although most of the farms have within the incorporated regions of
La Quinta no longer exist, agriculture is still an economic factor east of the incorporated
boundary, within the proposed Sphere of Influence and beyond.
The Riverside County Important Farmland 2008 Map, developed by the California Department
of Conservation, highlights areas within the Coachella Valley that are important agricultural
producing lands. Prime Farmland includes areas with both good physical and chemical attributes
able to sustain long-term agriculture production. Unique Farmland areas produce crops of
statewide importance; however contain lower quality soils than those within Prime Farmland.
Farmland of Local Importance are lands generally without irrigation, and which produce dry
crops that may be important locally, but are not important for statewide agriculture production.1
A portion of incorporated La Quinta, and land within the proposed Sphere of Influence Planning
Areas, contain lands listed as Prime Farmland, Unique Farmland, and Farmland of Local
Importance. In total, there are approximately 9,100 acres of such lands within the City limits and
Sphere of Influence.2
The General Plan Update will facilitate new urban development on lands deemed important
agricultural lands by the California Department of Conservation. Section III of this EIR provides
analysis on the potential impacts to agricultural resources from implementation of the proposed
General Plan Update.
1 Riverside County Important Farmland 2008 Map, prepared by California Department of Conservation, 2009. 2 As provided by City of La Quinta Planning Department through Riverside County Important Farmland GIS
Data, http://redirect.conservation.ca.gov/DLRP/fmmp/county_info_results.asp.
Terra Nova/La Quinta General Plan EIR
Section II. Regional Environmental Setting
II-3
Air Quality and Greenhouse Gasses C.
Air quality in a given location is influenced by the type and concentration of pollutants emitted
local and regionally. The Coachella Valley, including the City of La Quinta, is located within
the Salton Sea Air Basin (SSAB). The SSAB shares a boundary with the San Diego Air Basin to
the west, the South Coast Air Basin to the northwest, and the Mojave Desert Air Basin to the
north. The SCAQMD is responsible for establishing the criteria by which air quality is measured
in the Coachella Valley.
In the Coachella Valley, air quality has deteriorated over the last few decades due to increased
development and construction activities both locally and regionally. While local emissions of
pollutants affect air quality in the Coachella Valley, some of the air quality degradation can be
attributed to sources outside of the SSAB, particularly from within the South Coast Air Basin,
located west of the region.
Of all the criteria pollutants, ozone and suspended particulates (PM10 and PM2.5) are the most
prevalent in the Coachella Valley; other pollutants are not believed to constitute significant
threats to public health. Ozone and PM10 concentrations are recorded at monitoring stations in
Indio and the Palm Springs International Airport. Data collected at local monitoring stations
show a downward trend in amount of days over ozone and PM10 thresholds, however the Salton
Sea Basin continues to be classified as a “serious” ozone non-attainment area.
The 2007 Air Quality Management Plan (AQMP) was prepared to satisfy the State
Implementation Plan requirements of the Clean Air Act, due to non-attainment status. In regards
to PM10 levels, the region has also historically been designated as a serious non-attainment area
for PM10, however due to new monitoring techniques that discount strong wind events, the
SCAQMD has worked on re-designating the area from non-attainment to attainment for PM10. The California Air Resources Board (CARB) approved SCAQMD’s PM10 Redesignation
Request and Maintenance Plan in February 2010. This Plan details how the Coachella Valley is
to proceed to improve its status from serious non-attainment to attainment for the PM10 National
Ambient Air Quality Standard.
In addition to criteria pollutants, the emission of greenhouse gases also affects local and regional
air quality. The City of La Quinta has prepared a comprehensive greenhouse gas reduction plan
in order to systematically identify emission sources and reduce emission levels. The City, in
keeping with AB 32, has set a reduction target of 10% below 2005 levels for the year 2020. The
2005 inventory estimated that community wide emissions totaled 460,946 metric tons of CO2e.
Therefore, in order to achieve 2020 reduction targets, community wide emissions of GHG’s will
have to be reduced to 414,852 metric tons of CO2e.
The 2035 General Plan Update will facilitate new growth in the region, which may impact air
quality. Section III of this EIR will address the potential impacts on air quality.
Terra Nova/La Quinta General Plan EIR
Section II. Regional Environmental Setting
II-4
Climate D.
La Quinta is located in a subtropical desert characterized by hot dry summers and cool dry
winters. The City’s climate is a direct result of the local geography and topography of the region.
La Quinta is located in the low-lying Coachella Valley on the eastern side of the San Jacinto and
San Bernardino Mountains. These mountains form a barrier between the moister coastal region
to the west and the dry desert regions to the east and southeast. The mountains create a rain
shadow effect on the Coachella Valley and reduce the amount of precipitation the Valley
receives from winter storms that originate over the Pacific Ocean. Although the region remains
dry most days of the year, the Valley does experience periodic rainfall from strong winter storms
and summer monsoon thunderstorms.
The City of La Quinta experiences a dry subtropical desert climate. According to the Western
Regional Climate Center, which measures average temperature and rainfall at the nearby Indio
Fire Station, the average annual maximum temperature for the local area is 88.9° degrees, and
average annual minimum temperature is 58.0° degrees.3 The region is characterized by summers
with temperatures reaching well over 100° degrees during the day and staying above 70° degrees
at night. July is the warmest month in La Quinta, with average maximum temperatures reaching
107° degrees. January is the coolest month, with average maximum temperature reaching 70.6°
degrees. The coolest average minimum temperature also occurs in January, and reaches 39.1°
degrees. The surrounding mountain temperatures are cooler than those on the valley floor, and
typically experience a 5° degree Fahrenheit drop per 1,000-foot increase in elevation.4
La Quinta experiences periodic rainfall events primarily during the winter and summer seasons.
The average annual rainfall is 3.31 inches per year. During the winter months, La Quinta
receives an average of 2.01 inches of rainfall, with January typically being the wettest month.
Winter rains are a result of low-pressure systems dropping south from the Gulf of Alaska and
into Southern California. During El Nino years, the region can experience extended days of
strong winter storms.
Summer rainfall in the Valley occurs as a result of the monsoon season, which extends from July
through September when moist southeasterly winds draw moisture into the region from the Gulf
of California and Mexico. La Quinta averages 0.70 inches of rainfall during the summer, with
September averaging the most summer precipitation of 0.30 inches. Summer monsoon storms
tend to be localized thunderstorm events that can drop heavy rainfall over short periods of time.5
3 Western Regional Climate Center, http://www.wrcc.dri.edu 4 “Technical Background Report to the Safety Element of La Quinta 2035 General Plan Update”, prepared by
Earth Consultants, Inc., June 2010. 5 “Technical Background Report to the Safety Element of La Quinta 2035 General Plan Update”, prepared by
Earth Consultants, Inc., June 2010.
Terra Nova/La Quinta General Plan EIR
Section II. Regional Environmental Setting
II-5
Biological Resources E.
The Planning Area is located within the Colorado Desert Sub-unit of the Sonoran Desert. The
desert climate limits the types of vegetation that can be supported, and native vegetation is
typically sparse. In higher elevations conditions are less extreme, with milder temperatures and
higher annual rainfalls, which support a wider variety of plant and animal life.
In the Planning Area, naturally occurring habitat has largely disappeared as a result of agriculture
and urban development. Vegetation in the City primarily takes the form of non-native landscape
materials. However, native habitat is present on the slopes of the Santa Rosa Mountains. In these
areas, development potential has been limited by topography and restrictions on land use applied
by local jurisdictions, including the City and County, through the application of Open Space land
use designations, as well as through the Coachella Valley Multiple Species Habitat Conservation
Plan (MSHCP).
The Planning Area is within the boundaries of the MSHCP, a regional planning effort that
addresses the conservation of 27 species and 24 vegetation communities on more than 1.2
million acres in the Coachella Valley. The MSHCP has identified conservation areas throughout
the Coachella Valley. In La Quinta, these are limited to lands in the Santa Rosa Mountains and
its foothills, and are designated as Natural Open Space. Development on lands outside
conservation areas is subject to payment of mitigation fees through the MSHCP. The MSHCP is
further discussed in Section III-D.
As noted above, native vegetation in the City is most common within foothills, drainages and
streams within and near the mountains. The most common native plant community in the
Planning Area is Sonoran Creosote Bush Scrub, dominated by Creosote Bush, Burrobush,
Brittlebush and similar common species. Other native plant communities include Sonoran Mixed
Woody and Succulent Scrub, and Desert Dry Wash Woodland.
In the northern area of the City, windblown sandy habitat, including desert dunes and sand field
habitats, have given way to stabilized sand habitats as a result of development. Natural
communities have been degraded by the dominance of non-native and invasive species, and
remaining vacant parcels are generally isolated. There are no sand field habitats within the City
that have been identified for preservation in the MSHCP.
Desert Saltbush Scrub is prevalent in the Sphere. This plant community generally occurs on
poorly drained soils with high salinity or alkalinity, as is common on agricultural lands which
have lain fallow for long periods.
Common Wildlife Species
There are a variety of common wildlife species in the Planning Area, which are supported by
disturbed sand fields, saltbush scrub, agricultural and urban landscaping. Common species also
occur in habitats on the southern and eastern edges of the Planning Area which have been less
disturbed.
Terra Nova/La Quinta General Plan EIR
Section II. Regional Environmental Setting
II-6
Common insect species include Harvester Ants, Creosote Bush Grasshopper and Black Widow
Spider. Common amphibians include California Toad and Pacific Tree Frog. Common reptiles
found in the Planning Area include Zebra-tailed Lizard, Desert Horned Lizard, California
Kingsnake and Colorado Desert Sidewinder. A variety of birds are found in La Quinta and its
Sphere; these include the House Finch and House Sparrow, Abert’s Towhee, Mourning Dive and
Red-tailed Hawk. Common mammals include bats, the Black-tailed Jackrabbit, Pocket Mouse
and California Ground Squirrel.
Sensitive Species
Special status species are those that are considered threatened or endangered under the California
or federal Endangered Species Act. Several special status species are known to occur in the City
or Sphere of Influence, most notably the Coachella Valley Fringe-Toed Lizard, Burrowing Owl,
and Peninsular Bighorn Sheep. In addition to these species, habitat has been modeled for
Coachella Valley milkvetch, Desert Tortoise and Palm Springs Pocket Mouse, although these
species have not been observed in the City or Sphere. A complete discussion of sensitive species
thought to occur in the Planning Area is included in Section III-D.
Cultural Resources F.
Cultural resources within the La Quinta General Plan Update Planning Area, includes
paleontological remnants, artifacts from prehistoric cultures and more recent cultures, and
culturally important buildings and structures.
During the late Miocene and early Pliocene era, or approximately 5 million years ago, the Salton
Trough was an extension of the Gulf of California. Fossils from this time period have been found
in sediment in the northern portion of the Coachella Valley, including the Painted Hills, Garnet
Hill, and two places in the Indio Hills. In more recent time, repeated inundation of ancient Lake
Cahuilla has resulted in the identification of fossils of snails and mollusks in the City and Sphere.
Early human settlement occurred throughout California approximately 8,000 to 12,000 years
ago, during the beginning of the Holocene period. Native Americans occupied lands throughout
the Coachella Valley during these ancient times. Historical records show that early Native
American peoples in the Coachella Valley were from the Takic speaking Cahuilla tribe. Among
this tribe were separate groups including the Pass Cahuilla, who occupied the modern day San
Gorgonio Pass and Palm Springs area, the Mountain Cahuilla, who occupied the San Jacinto and
Santa Rosa Mountains, and the Desert Cahuilla, who occupied the eastern Coachella Valley,
which includes modern day La Quinta.
The first noted European explorations in the Coachella Valley occurred in 1823-1825 when
Spanish explorers Jose Romero, Jose Maria Estudillo and Romualdo Pacheco led expeditions to
find a route to current day Yuma, Arizona. These explorers traveled through the Coachella
Valley on what was known as the Cocomaricopa Trail, which was an ancient Indian trading
route. By the 1860’s, other European explorers, including William David Bradshaw, began
traveling along the Cocomaricopa Trail and renamed it the Bradshaw Trail. Throughout the late
1800’s, the Bradshaw Trail was a commonly utilized route, until the completion of the Southern
Terra Nova/La Quinta General Plan EIR
Section II. Regional Environmental Setting
II-7
Pacific Railroad in 1876. By the 1870’s non-native settlements began to occur across the
Coachella Valley, as new federal laws, including the Homestead Act and Desert Land Act,
opened lands for new settlers. The discovery of underground water sources began to increase
farming activities throughout the Valley in the early 20th century. By 1910, the date palm
industry began to flourish in the region.
Tourism reached La Quinta and the Coachella Valley in the 1920’s, as the rich and famous of
Hollywood began coming to the Valley to enjoy the beautiful scenery and climate. The La
Quinta Resort was developed in 1926 and became a focus of the local economy.
The entire Coachella Valley began to boom after World War II, as more residents and visitors
came to the area in pursuit of desert living and to enjoy newly developed golf facilities. Today,
La Quinta continues to experience new growth and development based on this tradition.6
The General Plan Update will facilitate future growth in the City and Sphere of Influence
Planning Areas. New development has the potential to impact cultural resources by both
affecting identified cultural resources and those that may become unearthed due to grading
activities. Section III of this EIR will address the impacts associated with cultural resources
within the City of La Quinta and the Sphere of Influence Planning Areas.
Geology and Soils G.
Geology
The Planning Area is located in a geologically complex and seismically active region. Much of
Southern California, including the Coachella Valley and La Quinta, occurs along the boundary of
the Pacific and North American tectonic plates. These plates slide past each other in a
northwesterly direction at a rate of approximately 2.5 inches annually, forming the San Andreas
Fault system. Based on the frequency and magnitude of earthquakes, and its influence over
seismic hazards in the area, the San Andreas is considered the “Master Fault” in Southern
California. The Southern segment of the San Andreas fault zone passes approximately 4 miles to
the northwest of the Planning Area.
The Planning Area is also located in proximity to other active fault zones, including the San
Jacinto fault zone, which occurs approximately 16 miles to the south, as well as other smaller
faults. The Planning Area is subject to seismic risks from several types of earthquake-producing
faults. In addition to strong groundshaking from earthquakes, geological hazards that may affect
the Planning Area include liquefaction, rockfall, and seismically induced settlement.
Section III-F, Geology and Soils, provides a detailed discussion of faults and associated hazards
with potential to impact the Planning Area.
6 “Cultural Resources Technical Report for City of La Quinta General Plan (2010 Update), prepared by CRM
Tech, July 8,2010.
Terra Nova/La Quinta General Plan EIR
Section II. Regional Environmental Setting
II-8
Soils
Soils in the Planning Area are generally Holocene-age7 soils, comprised of alluvial, or
waterborne sand and gravel, lacustrine (lake) sediments, and Aeolian (windborne) sandy soils in
the valley portion of the Planning Area. Older, harder, crystalline rock that occurs in the
mountains weathers and forms boulders or further erodes. The latter creates fine particles that are
carried along canyons and drainages downslope, and are deposited as alluvial fans at the base of
mountain slopes.
The Planning Area and region were inundated by ancient Lake Cahuilla as recently as 400 years
ago. Lacustrine deposits may be up to 300 feet thick, and may form clay soils in the valley areas
where these soils alternate in layers with alluvial fan sediments and rock debris from the adjacent
mountains.
There are eleven primary soil series that have been mapped as occurring in the Planning Area.
Nine of these are formed in alluvium: Carrizo Stony Sand, Carsitas Sands, Coachella Sands,
Fluvents, Gravel Pits and Dumps, Gilman Sands and Loams, Indio Loams, Myoma Fine Sands,
Salton Fine Sandy Loam. Except for Salton Fine Sandy Loam, these soils are generally well-
drained. Two other soil types, Rock Outcrop and Rubble Lands dominate the western and
southern portions of the Planning Area, in and near the Santa Rosa Mountains and alluvial fans.
Much of the valley, including the Planning Area, is subject to high winds, which lift soils from
alluvial fans along the base of mountain slopes and canyons and other areas where loose, sandy
soils occur. These sediments are carried along the central axis of the valley, generally from the
northwest to southeast, creating a condition known as “blowsand”. This is further discussed in
Section III-F, Soils/Geology, and in Section III-C, Air Quality. Where these soils are deposited
they are subject to erosion. These soils are also generally considered compressible and
unsuitable for development without the implementation of specialized grading techniques.
A more detailed analysis of constraints and opportunities associated with soils in the Planning
Area is included in Section III-F.
Topography H.
The Coachella Valley and the City of La Quinta are located in a region that is subject to complex
and dynamic geologic forces that have, and continue to shape its dramatically varied topography.
The area is situated at the margin of the Colorado Desert and Peninsular Range physiographic
provinces. Each province comprises a distinct geologic and climatic region that has resulted in
diverse and unique landscapes. The Colorado Desert province, which encompasses the valley
floor portion of the Planning Area, is part of a low-lying basin extending from the Banning Pass
to the border with Mexico. To the southwest, the Planning Area enters the Santa Rosa Mountains
of the Peninsular Ranges province.
7 Deposited within the last 11,000 years.
Terra Nova/La Quinta General Plan EIR
Section II. Regional Environmental Setting
II-9
Portions of the foothills and eastern and northern facing slopes of the Santa Rosa Mountains that
comprise the southern and westernmost Planning Area and create views visible from the lower
elevations. Deeply incised canyons and rocky washes drain the mountains and foothills and
gradually descend into alluvial fans. From the base of the mountains, the Planning Area extends
east and north along the valley floor, gently sloping along a large alluvial fan that forms the Cove
area at the valley margin.
Elevations in the Planning Area range from approximately 190 feet below mean sea level in the
southeastern portion of the eastern Sphere of Influence, to approximately 1,700 feet above mean
sea level on the lower slopes of the Santa Rosa Mountains. Development opportunities and
constraints are informed by the area’s topography, with development generally limited to the
valley floor.
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Hazards and Hazardous Materials I.
The City of La Quinta is predominantly a residential community with scattered commercial
centers and limited quasi-industrial areas. There are currently no heavy industrial facilities in the
incorporated City or Sphere which generate large quantities of hazardous waste; however smaller
scale hazardous/toxic material generators exist throughout the region. These include dry cleaning
businesses, auto repair shops, gas stations, medical facilities, and pest control companies.
Additionally, many of the large agricultural production areas within the eastern Sphere, and golf
courses found throughout the City, use and store pesticides and fertilizers that can be harmful to
human health. According to the Department of Toxic Substances Control, there are no hazardous
waste sites in La Quinta or its Sphere listed under Government Code 65962.5 The closest site
listed is the Foster-Gardner site, which is a fertilizer and pesticide manufacturing plant located in
Coachella.8
There are also numerous transportation corridors running throughout the City and surrounding
area, including Highway 111, State Highway 68, Interstate 10, and the Southern Pacific Railroad.
These routes are used for transporting hazardous materials. The transporting of hazardous
materials along these corridors presents risks associated with the accidental release, spill, or
exposure of hazardous materials on existing and future populations.
The City of La Quinta adopted the Multi-Hazard Functional Plan in 1996 that addresses the
planned response to natural and man-made emergencies, including the release or spill of
hazardous materials.
Section III of this EIR will further discuss the impacts and precautions associated with hazardous
materials.
Hydrology and Water Quality J.
Hydrology
Although the climate in the Coachella Valley and the Planning Area are generally temperate,
seasonal storms can produce significant amounts of precipitation within short periods of time.
Winter storms are responsible for much of the area’s annual rainfall, and usually occur between
November and April. However, the region and surrounding mountains may also experience
localized thunderstorms at other times, especially during the summer monsoon season. Rapid
snowmelt from the mountains may also result in flooding downslope, including within the
Planning Area.
The Planning Area is subject to flash flooding along natural or man-made channels and sheet
flooding across the valley floor. Although of short duration, flash floods result in high peak
water volumes and velocities, which are frequently intensified by features of the local natural
and built environment. Rocky mountain slopes are steep and generally impervious, allowing for
little infiltration. Water collects rapidly, flowing into channels on the valley floor. Runoff flows
8 www.envirostor.dtsc.ca.gov, accessed November 2, 2010.
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frequently carry considerable debris such as mud, sand and rock fragments, which may clog
natural or built channels and restrict flow. When channels are impeded by debris or structures, or
when flows exceed channel capacity, sheet flow occurs, with waters overflowing channel banks.
Increased development also diminishes the area available for natural infiltration, replacing them
with buildings, sidewalks, parking lots, and roadways.
In addition to rainfall and snowmelt, flooding can also be caused by the failure of water retention
structures such as dams, levees, or above-ground reservoirs as a result of strong groundshaking
from earthquakes. The Planning Area is not considered at risk from inundation from dam
failure. Portions of the Planning Area have potential for flooding hazard from levee damage or
failure along the Whitewater River or from above-ground water storage tanks at higher
elevations within and adjacent to La Quinta. These risks are further discussed in Section III-H,
Hydrology, as well as Section III-F, Geology and Soils.
The Planning Area is characterized by braided, ephemeral streams that disperse at the base of the
mountains, as well as areas of sheet flow, described above. The main watercourse in the valley is
the Whitewater River, which drains an approximate 1,525 square-mile watershed at the Salton
Sea from the San Bernardino, Little San Bernardino, San Jacinto and Santa Rosa Mountains.
The River enters the lowlands near the southern San Gorgonio Pass, flowing southeasterly from
there, and ultimately draining into the Salton Sea, which lies southeast of the Coachella Valley.
In the City of La Quinta, the River is carried within the man-made Coachella Valley Stormwater
Channel.
Historical records collected by the Army Corps of Engineers show that the Whitewater River
experienced numerous large flood events in the 1800s, as well as many damaging floods in the
20th century. In 1965, damaging flood flows in the River in the lower Coachella Valley exceeded
10,000 cubic feet per second (cfs). This event stands as the maximum flood of record. The 1939
storm was the largest recorded storm in the Coachella Valley and is considered the standard
project flood for sizing regional flood control facilities. This 1939 storm is roughly considered to
be a 500 year storm.
Based on mapping prepared by the Federal Emergency Management Agency (FEMA), portions
of the Planning Area are within 100-year flood zones. These primarily include the Coachella
Valley Stormwater Channel as well as other channels and detention basins that serve as
stormwater management facilities. This is further discussed in Section III-H. Areas adjacent to
the stormwater channel, as well as the Cove community, lands south and southeast of Lake
Cahuilla, and portions of the City’s eastern Sphere are FEMA-mapped within the 500-year flood
plain.
Responsibility for analysis and design of flood control structures lies with Riverside County
Flood Control and Water Conservation District (RCFC&WCD). The Coachella Valley Water
District (CVWD) manages regional facilities, which collect runoff from areas outside the City,
including the mountains. CVWD has broad responsibility for planning, maintenance and
construction of regional facilities’ improvements. Regional facilities in the Planning Area
include the Coachella Valley Stormwater Channel (Whitewater River Stormwater Channel), the
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La Quinta Evacuation Channel, the Bear Creek System, the East La Quinta Channel and Lake
Cahuilla.
Maintenance of local facilities, which collect runoff from local streets and properties to regional
channels and basins, is the responsibility of the City of La Quinta. The City’s Master Drainage
Plan, updated in 2009, describes local facilities, which include storm drains, culverts and catch
basins within private development and local streets.
There are also several dikes in the Planning Area, which have been constructed to protect
developed areas on the valley floor from runoff from mountain slopes. Three of these dikes were
constructed by the Bureau of Reclamation, and are maintained by CVWD.
Issues related to flooding and hydrology, including a more detailed description of regional and
local flood control facilities, are discussed in Section III-H.
Water Resources/Quality
The Coachella Valley is underlain by a substantial subsurface groundwater basin, or aquifer, in
which groundwater has accumulated over millions of years, primarily from runoff from
surrounding mountains. The aquifer is naturally subdivided by fault barriers into subbasins,
which are further divided into subareas. Most of the Coachella Valley, including the Planning
Area, is underlain by the Whitewater River Subbasin.
Domestic Water Resources
The Coachella Valley Water District (CVWD) provides domestic and irrigation water to the City
and its Sphere. It uses wells to extract groundwater which naturally recharges from runoff from
the mountains. Natural recharge is supplemented by replenishment programs supplying
supplemental water to the Thomas E. Levy Groundwater Recharge Facility near Dike No. 4 and
at the Martinez Canyon Pilot Groundwater Recharge Facility near Martinez Canyon. These
ponds are supplied with imported Colorado River water delivered via the Colorado River
Aqueduct.
Whitewater River Subbasin
The Whitewater River Subbasin generally extends from the Whitewater River in the northwest to
the Salton Sea in the southeast, encompassing approximately 400 square miles. It is estimated
that Subbasin contains approximately 28.9 million acre-feet of water within the first 1,000 feet
below ground surface.9 There are five subareas within the Subbasin: Palm Springs subarea,
Garnet Hill subarea, Thermal subarea, Thousand Palms subarea, and Oasis subarea. The
Thermal subarea underlies the General Plan Planning Area, and is part of the Lower Whitewater
River Subbasin Area of Benefit.10
Since the early 1900s and the growth of agricultural uses in the Coachella Valley, groundwater
use in the Whitewater River Subbasin has been steadily increasing to a point where demand has
9 “Table 1, Engineer’s Report on Water Supply and Replenishment Assessment: Lower Whitewater River
Subbasin Area of Benefit, 2010-2011,” prepared by Coachella Valley Water District, April 2010. 10 “Engineer’s Report on Water Supply and Replenishment Assessment: Lower Whitewater River Subbasin Area
of Benefit, 2010-2011,” prepared by Coachella Valley Water District, April 2010.
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exceeded natural supplies. This condition, known as overdraft, has been exacerbated by
increased development of the Valley, with accompanying demands for water to irrigate
landscaped residential and resort areas and golf courses. CVWD data indicates that total water
demand in the Coachella Valley increased from approximately 96,300 acre-feet per year in 1936,
to 668,900 acre-feet per year in 1999.11 CVWD estimates that in 2009, there was a net loss in
water storage in the lower Whitewater River Subbasin, with total outflows exceeding total
inflows by 23,912 acre-feet.12
Water Quality
The Coachella Valley has generally good to excellent water quality, except where water tables in
the Subbasin are perched or semi-perched and groundwater contains high concentrations of
dissolved solids. Within the Sphere, groundwater quality may also be affected by long-term
discharge associated with septic systems. These impacts are generally less extensive and are
expected to be addressed over the long term as sewer facilities become available to these areas.
These issues are further discussed in Section III-P, Water Resources/Quality.
Existing Land Use K.
La Quinta is located in the desert region of Southern California, about 130 miles east of Los
Angeles in central Riverside County. The City lies in the south central region of the Coachella
Valley, in an area known as the Salton Trough, which is a fault-controlled valley basin with
expansive and varying geography and biological habitats. The City is located approximately two
miles south of Interstate 10, and can be generally described as being bound on the north by
Hovley Lane East, on the south by Avenue 64, on the west and southwest by the Santa Rosa
Mountains, and on the east by Harrison Street.
La Quinta historically has been a resort community attracting visitors from all parts of the
country. Recent growth, however, has focused on residential and retail development, providing
both a permanent home for year-round residents, and a second home for seasonal residents. The
City of La Quinta, and the Coachella Valley in general, are winter destinations for “snowbird”
residents who move to the desert from northern regions to escape the cold. As a result, a large
number of homes built throughout the City are considered second homes.
The existing land uses are indicative of the typical low-density residential neighborhoods,
country club communities, and resort developments across the Coachella Valley. Commercial,
industrial, and community uses also exist, but represent a smaller portion of the city. La Quinta
has set aside almost half of the land uses for open space, parks, and golf course facilities. These
areas provide numerous recreational opportunities and improve the quality of life for all
residents.
11 Table 3-1, “Coachella Valley Urban Water Management Plan,” Coachella Valley Water District, November
2000. 12 “Table 2, Engineer’s Report on Water Supply and Replenishment Assessment: Lower Whitewater River
Subbasin Area of Benefit, 2010-2011,” prepared by Coachella Valley Water District, April 2010.
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The 2002 General Plan currently includes three areas, including incorporated lands, two planning
areas, and the Sphere. Approximately 60% of these lands are designated residential, with 85%
designated as low density residential. The oldest neighborhoods are found in the Cove area, and
include a mixture of single-family and multi-family residences built around a north/south street
grid pattern. Vacant lots are still found in the Cove, and are likely to be developed as residential
in the future. More recent residential development has occurred in the southern portion of La
Quinta, and includes large country club communities, such as PGA West and Trilogy. The
northern residential communities include neighborhoods built at low and medium densities. The
northern subdivisions are more traditional neighborhoods without gates, as opposed to the new
developments found in south La Quinta, that tend to be primarily gated communities. The City’s
high-density residential land uses occur in the northern portion of the City. Areas within the two
planning areas covered by the 2002 General Plan to the east of the City are designated for low
density residential, and include large lot single family development and agricultural activities.
Commercial and office land use designations represent 4% of all land uses within La Quinta.
Mixed/Regional Commercial, Community Commercial and Tourist Commercial designations are
the most prevalent commercial uses, and make up 29%, 22%, and 21% respectively, of all
commercial lands. Commercial uses are located primarily along Washington Street, Highway
111, Jefferson Street, Monroe Street, and within the Village. Land uses found in the
Mixed/Regional Commercial designation include major retail centers with multiple anchor
tenants such as Walmart Supercenter, Costco, Home Depot, Target and Kohls department stores.
Small coffee shops, restaurants banks, service stations and boutique stores also are found in
Mixed/Regional Commercial. Land uses in Community Commercial include larger retail centers,
but have less acreage than retail centers in Mixed/Regional Commercial. Tourist Commercial is
associated with the hospitality and service industry and includes resorts, hotels, timeshares and
tourist commercial. An example of the Tourist Commercial land use is the La Quinta Resort,
which is a historic development in the Cove featuring suites, villas, casitas, pool & spa facilities,
tennis courts, five championship golf courses, and resort dining facilities.
La Quinta provides numerous passive and active recreational opportunities throughout the City,
in the form of open space, parks, and golf courses. Approximately 35% of all lands within La
Quinta are designated areas for community sporting events, golfing, hiking, picnicking,
mountain biking, and wildlife viewing. Lake Cahuilla is a Riverside County operated regional
park located in the southwestern portion of the City, and provides residents with equestrian
facilities, fishing, camping, and a seasonal pool. The open space areas throughout the western
portion of La Quinta include the Santa Rosa and Coral Reef Mountain areas, which provide
passive recreational opportunities.
The City of La Quinta currently does not have industrial designations in its incorporated limits,
however industrial lands are designated in surrounding planning areas. Major community
facilities are also distributed throughout the City, and include fire stations, schools, civic uses,
and major utility facilities.
The 2035 General Plan Update is proposing to consolidate land use designations from the current
2002 General Plan, and will also reduce the existing planning areas into two areas, consisting of
incorporated lands within City Limits and the Sphere of Influence.
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Section III of this EIR will discuss the environmental impacts associated with new 2035 General
Plan Update.
Surrounding Land Use L.
The City of La Quinta and its Sphere are located in the eastern Coachella Valley, along the base
of the Santa Rosa Mountains. The City is surrounded by other local jurisdictions, including the
cities of Palm Desert, Indian Wells, Indio, Coachella, and unincorporated areas of Riverside
County. Land uses within these jurisdictions are very similar to the existing land uses found in
La Quinta. Urban development has spread through the Valley primarily in a northwest to
southeast direction. Therefore areas surrounding the northern portion of the City tend to be more
urbanized than areas surrounding the eastern and southern portions of La Quinta.
The surrounding land uses in the northern portion of La Quinta fall within the jurisdictions of
Palm Desert, Indian Wells, and a small portion of unincorporated Riverside County. The land
uses within these jurisdictions include low-density residential neighborhoods, commercial uses,
and recreation facilities. The Indian Wells Tennis Garden, which is a 55-acre tennis and
entertainment facility, is located on the west side of Washington Street, between Fred Waring
Drive and Miles Avenue, in the City of Indian Wells.
The cities of Indio and Coachella abut La Quinta to the east and northeast. Land uses include
commercial, residential, and agricultural uses. The City of Indio has numerous large commercial
centers, including the Indio Plaza Shopping Center and the Indio Fashion Mall along Highway
111. Residential uses in Indio and Coachella tend to be more traditional open neighborhoods,
similar to those found in north La Quinta.
The unincorporated communities of Thermal and Vista Santa Rosa lie east of La Quinta. The
Vista Santa Rosa Community is a community recognized on the Riverside County General Plan
as an important producer of date palms, and also provides rural residential uses, equestrian uses
and polo facilities. The Jacqueline Cochran Regional Airport is located in the westerly portion of
Thermal, just east of the La Quinta Planning Area. Land uses in Thermal include light industrial,
which is generally associated with agriculture production and the airport, as well as scattered
residential and commercial uses.
The lands to the southeast and south of La Quinta are within the County of Riverside, and
include areas subject to Native American Tribal jurisdiction. These lands are primarily used for
agriculture production, rural residential, and open space.
Finally, the land uses surrounding the western border of La Quinta are within the County of
Riverside, and are designated for open space conservation. These lands are located in the Santa
Rosa and San Jacinto Mountains National Monument, which is a 271,400-acre reserve created in
2000 to preserve important biological resources. The Monument spans from the low desert to
artic alpine lands found on the 10,834-foot San Jacinto Peak. The National Monument provides
hiking opportunities and mountain vistas overlooking the City of La Quinta and the Coachella
Valley.
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Mineral Resources M.
The Coachella Valley contains valued mineral resources due to the region’s highly active
geologic nature. The numerous earthquake faults throughout the region create massive uplifting
and folding of the land, and expose mineral resources on the surface. Mineral resources found
throughout the region include sand, gravel, crushed stone, copper, limestone, and tungsten. Many
of these resources are important for common construction projects including asphalt, concrete,
road base, stucco and plaster.
The State of California Department of Conservation, Division of Mines and Geology, identified
areas in the Coachella Valley with important mineral resources, and classified areas into Mineral
Resources Zones. La Quinta and surrounding areas are classified into three zones, including
MRZ-1, MRZ-2, and MRZ-3. The majority of lands within the City and Sphere fall into MRZ-1,
which are areas where no significant mineral deposits are present, or are less likely to occur.
Many of these areas are already developed.
A small area of the City, near Lake Cahuilla, is located in MRZ-2, which includes areas where
significant mineral deposits are present. This area is no longer used for gravel and sand mining
production, but has been developed as The Quarry golf community. The third zone found in La
Quinta includes the MRZ-3 area, which includes the Santa Rosa Mountains, foothills, and the
Cove portion of La Quinta. Lands within this zone contain mineral deposits, however the
significance of these deposits has not been evaluated.13
Future mining within the City of La Quinta and surrounding Sphere of Influence is unlikely due
to the establishment of conservation areas, such as the Santa Rosa Wilderness Area, and due to
existing urbanization.
Section III of this EIR will assess the potential impacts on mineral resources as a result of the
2035 General Plan Update.
Noise N.
Noise pollution is an unseen pollutant created by unwanted or undesired sounds. Excessive noise
levels can create physical and psychological distress and harm to human beings, leading to
temporary or permanent hearing loss, anxiety, high blood pressure, sleep deprivation, and overall
reduction in quality of life. Due to the detrimental effects of excessive noise levels, the State of
California has required local municipalities to include a Noise Element in their General Plans.
Municipalities are also required to have noise ordinances to establish maximum ambient noise
levels for sensitive areas.
13 City of La Quinta General Plan/Master Environmental Assessment, prepared by Terra Nova Planning &
Research, March 20,2002.
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The City of La Quinta currently has a Noise Ordinance and Noise Element within the 2002
General Plan to prevent excessive sound levels, which are detrimental to the public health,
welfare and safety of residents. The Noise Ordinance and Noise Element establish exterior noise
standards for various land uses, and appropriate time periods for construction other types of
noise.
Noise is measured using the decibel (dB) as a unit of measurement, which describes the
amplitude or strength of sound. Most common sounds range from 40 decibels (dB) to 100 dB. A
normal conversation, for example, usually measures around 60 dB at a distance of 3-feet. A jet
engine, on the other hand, can measure up to 110 dB, which is considered very loud and
discomforting. Within the built environment, noise is created from various sources, including
traffic, construction equipment, machinery, and people. The combination of sounds created by
these various sources is called the ambient noise level.
Most municipalities analyze ambient noise levels to accurately measure the amount of noise
affecting sensitive receptors, such as schools, residential units, or hospitals. Ambient noise is
measured using Community Noise Equivalency Level (CNEL) units, which is a weighted
average of the intensity of sounds over a 24-hour period. CNEL accounts for time of day and
adds additional decibels during sensitive periods, such as between 10 p.m. and 7 a.m. The CNEL
weighted decibel unit is called dBA. The City of La Quinta has determined that a CNEL of less
than 65 dBA of exterior noise is acceptable for sensitive receptors.14
The City and Sphere are affected by noise from both mobile and stationary sources. Noise
generated from vehicular traffic is the largest contributor of ambient noise in the City, however
noise levels are also elevated due to nearby railway traffic, airplanes, construction activities and
mechanical equipment. These noises can present a nuisance to sensitive receptors, including
residential uses, hospitals, day care facilities, and schools. Various noise attenuation methods,
including the use of double paned windows, walls, landscaping, and other construction
techniques can help reduce the amount of exterior noise reaching sensitive receptors.
Future development proposed by the General Plan Update will continue to increase ambient
noise levels within the La Quinta Planning Area. Section III of this EIR further addresses the
existing and build out noise environment, and potential noise impacts associated with the
implementation of the General Plan Update.
Population and Housing O.
The 2010 Census accounted for a total of 23,489 dwelling units within the City of La Quinta, and
an estimated population of 37,467. The total number of occupied dwelling units within the City
was identified as 14,820. Thus, nearly 37 percent of all housing units within La Quinta were
unoccupied in 2010. The relatively high vacancy rate is largely due to seasonal, recreational, or
occasional use homes, which account for 27.5% of all housing units. Although seasonal,
14 City of La Quinta General Plan/Master Environmental Assessment, prepared by Terra Nova Planning &
Research, March 20, 2002.
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recreational, and occasional residents generate a demand for services and utilize local
infrastructure and utilities, they are not accounted for in the La Quinta population figure of
37,467.
The 2010 population size of 37,467 and the 14,820 occupied dwelling units yield an average
household size of 2.53. In order to estimate the full occupancy population for the City of La
Quinta, the per household population size of 2.53 was multiplied by the existing number of
dwelling units (23,489). Thus, the full occupancy population size of La Quinta in 2010 was
approximately 59,427 people.
In 2010, the Sphere of Influence contained 801 dwelling units. Assuming a population size of
2.53 and full occupancy, the Sphere’s 2010 population was 2,027 people.
The overall Planning Area contained an estimated 24,290 dwelling units in 2010, which could
support a total population size of 61,454 people.
Public Services and Utilities P.
The City of La Quinta and its and Sphere of Influence are served by a range of public service and
facilities, such as local and regional governmental services, special districts, public utilities, and
associated services and facilities. The following identifies the various public services and utilities
that are available within the City of La Quinta and the Sphere.
Fire Protection
Fire protection services within the City and Sphere are provided by the Riverside County Fire
Department through a contractual agreement with the City. There are a total of six stations
available to respond to calls within the Planning Area, all staffed by full-time, paid firefighters as
well as volunteers. There are three City-owned stations in the City of La Quinta. Three additional
stations within the County Fire Department system are available for emergency response: one in
Indian Wells, one in Indio, and a third at the Jacqueline Cochran Airport, east of the City’s
eastern Sphere. The County dispatches calls through its centralized Emergency Command
Center, which determines the responding station(s) based on location and need. In 2010, stations
averaged a response time of between 5 and 7 minutes. The County also uses its dispatch system
to provide ambulance services through its service provider, American Medical Response (AMR).
Police Protection
The City contracts annually with the Riverside County Sheriff’s Department for police services,
as it has since its incorporation in 1982. Within City limits, the Department operates as the La
Quinta Police Department, and utilizes dedicated facilities, equipment and personnel. Police
protection through the Sheriff’s Department also extends to the City’s Sphere. The Sheriff’s
Department provides police protection throughout the Planning Area on a 24-hour basis. There
are two Police Department offices in the City. The Sheriff’s Department also uses a third
location, within the community of Thermal, for police services as well as jail facilities. The
City’s 2010 contract with the Sheriff’s Department provides for the equivalent of 50.75 sworn
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officers and 5 community service officers. The Department provides a variety of services within
the Planning Area. These are further described in Section III-M.
Solid Waste Management
Burrtec Waste and Recycling Services, LLC (Burrtec), provides solid waste disposal in the City
through a franchise agreement with the City. Solid waste collected in La Quinta is transported to
the Edom Hill Transfer Station to the west in the City of Cathedral City. From Edom Hill, waste
is transported to one of three regional landfills: Lamb Canyon, Badlands or El Sobrante, each of
which has remaining long-term capacity. Burrtec also provides solid waste recycling in the City
to residential and commercial customers; green waste recycling is also available.
Domestic Water
Coachella Valley Water District (CVWD) is the domestic and irrigation water provider to the
City and most of the Sphere of Influence. It sources most of its water supplies from groundwater,
which is extracted through a system of wells located throughout the region, including La Quinta.
CVWD also imports water to recharge the aquifer, using recharge basins located near Palm
Springs and south and east of the Planning Area at the Thomas E. Levy Groundwater Recharge
Facility near Dike No. 4 and at the Martinez Canyon Pilot Groundwater Recharge Facility near
Martinez Canyon. CVWD’s water distribution system is generally located in public rights of way
under existing streets. There are 10 existing or planned CVWD water storage tanks in the
Planning Area.
California Water Code requires that CVWD prepare and periodically update an Urban Water
Management Plan (UWMP) to analyze its current and future water supply. The UWMP is
intended to ensure that sufficient supplies are available to serve land uses within its management
area.
Wastewater Services
In addition to domestic water services, CVWD provides the City with wastewater collection and
treatment facilities. Sewer collection facilities are available in most areas of the City and Sphere
of Influence, although septic systems are still utilized in some areas, primarily in the Sphere.
CVWD has a system of wastewater lines throughout local streets, as well as force mains within
major roadways. There are two CVWD wastewater treatment plants serving the City. Water
Reclamation Plant 7 (WRP-7), serves the portion of the City north of Miles Avenue. Lands in the
City and Sphere located south of Miles Avenue are served by Water Reclamation Plant No. 4.
WRP-7 has the added capability to process wastewater to tertiary levels (suitable for irrigation).
There is no tertiary treatment available at Water Reclamation Plant No. 4.
Schools
The Planning Area lies within the boundaries of two public school districts. The Desert Sands
and the Coachella Valley Unified School Districts (DSUSD and CVUSD, respectively) each
provide public education for students in grades Kindergarten through 12 to students within their
district boundaries.
DSUSD serves students located west of Jefferson Street and north of Avenue 48. This includes
the City’s northern Sphere of Influence. There are seven DSUSD schools in La Quinta, including
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three elementary schools, two middle schools, one high school and one alternative school. In
addition, the District’s administrative offices are located in the City, on Dune Palms Road, south
of Highway 111. DSUSD also provides early childhood education, after school programs. and
special education services. It further serves adult GED, English as a second language, and
citizenship students.
Students residing east of Jefferson Street and south of Avenue 48, including the City’s eastern
Sphere of Influence, are served by CVUSD. There are two CVUSD schools in the Planning
Area, including one elementary school and one middle school. Additional schools are located
outside the Planning Area. CVUSD also operates an adult school that offers special education
and tutoring services, as well as vocational training, preparation for GED testing, and citizenship
classes.
There are three regional higher education institutions located in the nearby City of Palm Desert.
These include the College of the Desert, a community college with associates degree and adult
education programs; California State University, San Bernardino and the University of
California, Riverside, each of which offers undergraduate and Master’s degree programs.
Libraries
The La Quinta Library is located at 78-275 Calle Tampico. The City owns the library facility,
which is operated by Riverside County. The Library contains 89,060 volumes within a 20,000
square foot space. Although the City has not established a standard for library facilities, the
County Library system aims for an un-adopted standard of two volumes per capita. Based on this
standard, existing library facilities are sufficient to serve the current population.
Medical Facilities
In addition to a variety of small clinics and local physician’s offices throughout the Coachella
Valley, there are three major regional health care facilities, all available to serve the Planning
Area. These are briefly described below:
John F. Kennedy Memorial Hospital
The John F. Kennedy Memorial Hospital in the City of Indio is a 158-bed facility. It has a 24-
hour emergency room, maternity care and pediatric services, an ambulatory surgery center, and
an outpatient rehabilitation center. It also offers imaging services, orthopedic and joint
replacement services, cardiovascular services, and a sports medicine program.
Eisenhower Medical Center
The Eisenhower Medical Center (EMC) in Rancho Mirage includes a 313-bed hospital on its
130-acre campus. EMC also houses an emergency room, as well as the Annenberg Center for
Health Sciences, the Barbara Sinatra Children’s Center, and the Betty Ford Center.
EMC recently completed the 92,000 square foot Eisenhower George and Julia Argyros Health
Center in La Quinta, which includes an outpatient facility, express clinic, a pharmacy, laboratory,
primary care physicians’ offices, an executive wellness program, and an imaging center.
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Desert Regional Medical Center
The Desert Regional Medical Center (DRMC) in Palm Springs is located approximately 20 miles
east of La Quinta. DRMC houses 367 beds, providing general medical facilities, inpatient and
outpatient rehabilitation services and the Level II Richards Emergency Trauma Center staffed 24
hours a day, seven days a week with at least one physician. DRMC is the only designated
Trauma Center in the Coachella Valley.
Municipal Facilities
The City provides municipal services and programs to the community through a variety of
municipal facilities. These include City Hall, the Senior Center, the La Quinta Library and the La
Quinta Museum. With the exception of the Museum, these facilities are clustered within or near
the City Civic Center complex, located at 78-495 Calle Tampico. The City also owns a
municipal golf course and several parks facilities, which are further described in Sections II-Q
and III-N, Recreational Resources.
Telephone and Telecommunications
Verizon serves as the primary telephone (land line) provider in the City. Given improvements in
technology and decreased regulation in telephone service, the public now has access to a variety
of choices, including cable-based and cellular services. New technologies are expected to
continue to develop that will ensure the adequate provision of telephone and telecommunications
to residences, businesses and other users in the Planning Area.
Electricity
The Imperial Irrigation District (IID) provides electric power to the Planning Area. IID delivers
power through generation as well as through contractual agreements with other providers. It has
substations throughout the City, from which it steps down voltage for distribution to its
customers. Residential uses account for the highest demand for electric power in the Planning
Area.
Natural Gas
The Gas Company provides natural gas where facilities are available within the Planning Area.
Although there are major supply lines in Washington Street and Highway 111, service is limited
in some portions of La Quinta and its Sphere. This is true of areas south of Airport Boulevard
and east of Monroe Street, as well as parts of the Cove community, and some older
developments in the Sphere. Residents in these areas rely on propane gas purchased from private
firms.
Potential impacts to public services and utilities from implementation of the proposed General
Plan Update are analyzed in Section III-M.
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Section II. Regional Environmental Setting
II-23
Recreation Q.
Approximately 35% of all lands in the 2002 General Plan planning area are designated for open
space, parks, and/or golf courses. Approximately 53% of lands within incorporated La Quinta
alone are designated with land uses that support recreation.15 Recreational services and facilities
are operated and maintained by four agencies, including the Riverside County Regional Parks
and Open Space District, the City of La Quinta Community Services Department, the Desert
Recreation District, and the Bureau of Land Management. In addition, there are many privately
owned golf courses throughout the City.
The largest recreational opportunity in La Quinta is golf. Golf courses and golf clubs in the City
hold various tournaments throughout the year, including the Humana Challenge, formerly the
Bob Hope Classic.16
One of the largest parks within the City of La Quinta is the Lake Cahuilla County Park. Lake
Cahuilla is an 845-acre park located in the southwestern portion of incorporated La Quinta. The
County of Riverside operates and maintains the facility. Recreational opportunities at Lake
Cahuilla include fishing, equestrian trails, camping, horse camps, and hiking. There is no
swimming allowed at the lake, however a seasonal swimming pool is open during the summer.
The Desert Recreation District owns and operates the La Quinta Community Park in La Quinta.
This 6.5-acre park includes a 5,000 square foot community center, baseball diamonds, basketball
courts, a playground and picnic pavilion.
The La Quinta Senior Center is owned and operated by the City, and was built in 1994 to provide
educational and recreational opportunities for local seniors. The 10,500 square foot facility
includes multi-purpose rooms, kitchen, computer lab, health center, and other senior serving
amenities.
The City of La Quinta Community Services Department maintains numerous small pocket parks,
neighborhood parks, community parks, and trails throughout incorporated portions of the City.
Pocket parks are generally less than one acre, and provide small playgrounds, tot lots, and
passive seating areas. These small parks tend to be built within neighborhoods and serve local
residents. Neighborhood parks are larger than pocket parks, but also are built to serve residents
in local neighborhoods. These parks are generally two to ten acres and offer walkways, benches,
and picnic areas, as well as active recreational opportunities such as playing fields, basketball
courts, and playgrounds.
Community parks are larger scale parks and provide regional recreational opportunities for
residents in La Quinta as well as the surrounding region. These parks generally range in size
from twenty to forty acres and include large sport complexes that provide lighted multi-purpose
fields, public restrooms, snack bars and shade structures. The City has joint ownership with
15 “City of La Quinta General Plan/Master Environmental Assessment”, prepared by Terra Nova Planning &
Research, March 20, 2002. 16 http://www.playinlaquinta.com/golf.html
Terra Nova/La Quinta General Plan EIR
Section II. Regional Environmental Setting
II-24
Desert Sand Unified School District for the La Quinta Sports Complex, which is an 18.2-acre
community park located off Avenue 50 near Washington Street.
The City has also coordinated with Family YMCA of the Desert to maintain the swimming pool
at Fritz Burns Park, located near Avenue 52 and Avenida Bermudas.
The City has developed Class I, II, and III facilities for cyclists and pedestrian use. Existing bike
routes link all portions of the city, including from the southern boundary to the northern city
limits.
Bear Creek Path, located in the western portion of the Cove provides a popular paved walking
trail along Bear Creek. In addition, there are numerous unpaved trails that provide access to open
space areas. The Bear Creek Canyon Trail in the southern portion of the Cove provides hikers
with approximately 4.5 miles of trail into the Santa Rosa Wilderness Area. Other trails in the
region include the Boo Hoff Trail and the Cove to Lake Trail, which links Lake Cahuilla Park
with the Cove.17
The City of La Quinta is located adjacent to some of the most expansive open space areas within
the Coachella Valley. The southwestern portion of the City borders the Santa Rosa Wilderness
Area, which is maintained by the Bureau of Land Management.
The General Plan Update will facilitate new growth and development in incorporated La Quinta
and its Sphere of Influence. As growth and development occur, additional park and recreation
facilities will be needed. Section III of this EIR further discusses the impacts that growth will
have on recreation resources.
Transportation/Traffic R.
The pattern of the regional transportation network in the Coachella Valley has been affected by
geographic orientation, topography and climate. Several major roadways accommodate regional
traffic in the Coachella Valley, and include the U.S. Interstate-10 freeway, and Highways 111,
86, 74 and 62. U.S. Interstate-10 connects the Coachella Valley with the Los Angeles-Riverside-
San Bernardino metropolitan areas to the west, and Phoenix to the east. Highway 111 is an
essential intra-valley roadway which connects the Coachella Valley with the Imperial Valley to
the southeast. Highway 74 connects the central Coachella Valley with mountain communities,
southwestern Riverside County and northern San Diego County. State Highway 86 also provides
important regional access to the eastern Coachella Valley and the Imperial Valley, while
Highway 62 connects the valley to communities in the high desert Morongo Basin to the
northwest.
The City of La Quinta and the Coachella Valley have continued to be one of the fastest growing
regions in California. Major traffic corridors in the General Plan study area include Highways
17 “Parks and Trails”, http://www.la-quinta.org/Index.aspx?page=19, accessed June 28, 2011.
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Section II. Regional Environmental Setting
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111 and 86, and other planning area roadways such as Washington Street, Fred Waring Drive
and Jefferson Street.
Within the City and planning area, the road network essentially follows a north-south/east-west
grid with interconnections to major arterials. North-south traffic is channeled through major
arterials such as Washington Street and Jefferson Street, while other arterial streets such as Fred
Waring Drive and Avenue 52 convey east-west traffic. The roadway network in the City and
unincorporated portions of the planning area is only partially built out.
Roadway Segments and Intersections
A wide range of City and planning area roadways have been analyzed in the General Plan Traffic
Study, which is reproduced in Appendix H of this EIR. This analysis shows that several roadway
segments in the planning area are heavily congested, including portions of Washington Street,
Fred Waring Drive and Highway 111.
The General Plan traffic analysis studied existing conditions along sixty-three (63) roadway
segments and at thirty-seven (37) of the major intersections in the planning area. The assessment
of existing conditions indicates that all but two of the 37 intersections analyzed are operating at
Level of Service (LOS) C or better. The exceptions are the intersections of Washington Street at
Highway 111 and Madison Street at 50th Avenue, which are currently operating at LOS D. An
analysis of current operations along the 63 roadway segments analyzed indicates that all are
operating at LOS A, with the exception of three segments on Washington Street and one segment
on Highway 111 that are operating at LOS B.
Current and future traffic conditions and demand are further addressed in Section III-O.
Terra Nova/La Quinta General Plan EIR
Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
III-1
LA QUINTA GENERAL PLAN
ENVIRONMENTAL IMPACT REPORT
III. EXISTING ENVIRONMENTAL CONCERNS, PROJECT IMPACTS AND
MITIGATION MEASURES
Aesthetics A.
Introduction and Background
The La Quinta General Plan Update Planning Area is located in the eastern portion of the
Coachella Valley, along the base of the Santa Rosa Mountains. The desert setting and
surrounding mountains provides picturesque backdrop and aesthetically pleasing environment
for the community. This section describes the existing aesthetic qualities of the La Quinta
Planning Area for the 2035 General Plan Update, which includes the incorporated portions of the
City and the two Sphere of Influence areas. It also discusses the potential impacts that may occur
from implementation of the General Plan Update and provides mitigation measures to reduce
impacts to visual resources.
Thresholds of Significance/Criteria for Determining Significance
Article 5, Section 15064 of the CEQA Guidelines provides guidance for determining the
significance of the environmental effects caused by a project. Appendix G of the CEQA
Guidelines provides a list of environmental factors that potentially may be affected by
completion of a project. The La Quinta 2035 General Plan Update would have a significant
effect on aesthetics if it is determined the project:
a) Has a substantial adverse effect on scenic vista.
b) Substantially damages scenic resources, including, but not limited to, trees, rock
outcroppings, and historic buildings within a state scenic highway.
c) Substantially degrades the existing visual character or quality of the site and its
surroundings.
d) Creates a new source of substantial light or glare, which would adversely affect day
or nighttime views in the area.
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Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
III-2
1. Existing Conditions
Regional Setting
The Planning Area for the City of La Quinta 2035 General Plan Update is situated in the eastern
portion of the Coachella Valley in central Riverside County. The region is in an area known as
the Salton Trough, which is a fault controlled basin caused by the complex system of faults
crossing the region, including the San Andreas Fault. The Salton Trough is an expansive basin
that runs in a northwest to southeast direction, and includes varying topography and wildlife
habitats. Within the General Plan Update Planning Area, elevations range from 190 feet below
sea level in the southeastern portion of the Planning Area to 1,600 feet above sea level along the
peaks of the Coral Reef Mountains in the southwestern portion of the Planning Area. Other
topographic features in the region include the Indio Hills, located northeast of the Planning Area,
and the Santa Rosa Mountains, located west of the Planning Area.
The City of La Quinta is part of a larger community of local jurisdictions that make up the
Coachella Valley. To the north of La Quinta are the cities of Palm Desert, Indian Wells, Indio,
and a small portion of unincorporated Riverside County. These communities are primarily made
up of low-density residential neighborhoods, commercial centers, and resort and entertainment
facilities. Jurisdictions to the east of La Quinta include Indio, Coachella, the communities of
Vista Santa Rosa and Thermal. Land uses in these areas are predominantly low-density
residential and commercial, but also include agricultural lands, polo fields, rural residential, and
a regional airport. To the south of La Quinta are lands within the jurisdiction of the County of
Riverside, and areas subject to Native American Tribal jurisdiction. These areas are
predominantly agricultural lands, rural residential uses, and vacant desert lands. To the southwest
and west of La Quinta is public open space that is conserved as part of the Santa Rosa and San
Jacinto Mountains National Monument.
Existing Scenic Conditions
The La Quinta General Plan Update Planning Area is comprised of many land uses, including
residential, commercial, resort facilities, office parks, agricultural facilities, golf courses, open
spaces, and vacant land. These land uses are built primarily on the Valley floor and within the
Cove. Development within the City Limits is generally built at lower densities, and buildings
throughout the Planning Area tend to be low-rise structures. Views of local mountains and scenic
vistas throughout the incorporated portions of the City are generally good, however suburban
development, including buildings, walls, and mature landscaping can limit views in certain
places.
The eastern Sphere of Influence is rural and sparsely developed. Land uses in the Sphere include
single family residential, agricultural production and equestrian uses. There is also a considerable
amount of fallow vacant land once used for agriculture. Views of local mountains and scenic
vistas throughout this portion of the Sphere are preserved and unobstructed due to sparse
development. As a result of this rural character, the aesthetic quality is more open and views of
surrounding mountains are less restricted when compared to the more developed portions of the
region.
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Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
III-3
Visual Character
The existing visual character of the Planning Area can be characterized as both suburban and
rural. The incorporated portion of La Quinta exemplifies suburban character. La Quinta’s
suburban character is influenced by typical suburban land uses, including residential
neighborhoods, commercial shopping centers, office parks, golf courses, parks, and community
facilities. These land uses are built along landscaped boulevards with curb, gutter and sidewalks.
Large retail centers are located along Highway 111, while community scale commercial
development occurs on Washington Street and Jefferson Street.
The eastern Sphere can be characterized as more rural, and lack many of the suburban features
found throughout the incorporated portions of La Quinta. Development is sparse, and land uses
are predominantly associated with agricultural production, ranches, or nurseries. Existing
residential uses within these areas are predominantly on larger lots. An exception is a single-
family neighborhood near Jackson Street and Avenue 55, which is more typical of a suburban
style subdivision. Roads throughout the eastern Sphere of Influence tend to be two-lane rural
roads built without sidewalks, curbs and gutters, or landscaping.
Architectural Styles
La Quinta includes a mixture of building types built over various time periods, and with a variety
of architectural styles. Development includes structures built in the early twentieth century, and
new master-planned communities built within the last decade. Architectural styles include those
typical of Spanish Colonial, Mediterranean, Tuscan, and Modern styles. Spanish Colonial
architecture is the most prevalent style used in La Quinta, and examples include the La Quinta
Resort & Spa and the more recent Old Towne development in the Village.
Architectural styles throughout the Sphere of Influence Areas are limited and are associated with
rural lifestyle. Large equestrian facilities and ranch style homes on large lots are scattered
throughout the area.
Light and Glare
Existing sources of light and glare in the Planning Area are found mostly within the city limits.
Large commercial centers along Highway 111 produce light and glare from parking lots, signs,
and street lighting for security purposes. There are also various car dealerships along Highway
111 that produce light and glare for security purposes. Existing school playfields and recreational
facilities, such as La Quinta Park and La Quinta Community Park, also produce light and glare
from overhead field lights. Major arterials throughout the City produce light and glare from
street lamps, signalized intersections, and vehicle headlights.
Light and glare within the Sphere of Influence is minimized by the lower intensity of existing
development. The eastern Sphere is dominated by vacant desert, agricultural fields and very low
density residential, which produce lower levels of light than the urbanized areas of the City. The
lack of street lights and traffic signals in the area also limit the amount of light and glare.
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Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
III-4
2. Project Impacts
The 2035 General Plan Update will facilitate new development throughout the Planning Area
through the adoption of its Land Use Map, and policies promoting development. Therefore, the
General Plan Update has the potential to impact the existing aesthetic quality of the Planning
Area. The General Plan Update does not, however, propose any significant changes to the land
use pattern in the City.
The General Plan Update designates the Sphere for low density residential, commercial,
industrial, and community facilities. The General Plan Update also requires the master planning
of the eastern Sphere. This master plan could change the character of the eastern Sphere in the
long term, should these lands be annexed into the City.
The following discussion highlights the potential impacts on aesthetic resources, including scenic
vistas, scenic resources, visual character, and light and glare from implementation of the 2035
General Plan Update.
Scenic Vista Impacts
Within the Planning Area, scenic vistas include views of natural features, including the Santa
Rosa, San Jacinto, and Little San Bernardino Mountains.
The General Plan Update will facilitate new development in areas that are currently vacant, and
encourage redevelopment in existing urbanized areas within the City. The development of new
manmade structures, including buildings, streets, signage, walls, and landscaping, has the
potential to replace or disrupt views of the surrounding natural landscape. Redevelopment
projects in existing urbanized areas may also potentially affect the scenic vista if they increase
the intensity of the built environment. Conversion of empty lots or parking lots into new compact
developments or structures increase the potential to block views of the surrounding desert and
mountains from existing development.
Within the eastern Sphere, the General Plan Update will allow new residential, commercial and
industrial uses upon annexation, on lands that are currently used for agriculture. The conversion
of agricultural land has the potential to change the rural character of the area, and diminish the
openness and views of nearby mountains. As described above, however, the General Plan Update
includes master planning of the Vista Santa Rosa area prior to annexation or development in the
City. The stated purpose of this master planning effort is the preservation of the neighborhoods
character. In addition, the Sphere area will be subject to the policies and programs of the Land
Use and Sustainable Community Elements if annexed.
The General Plan Update provides policies and programs to protect existing views and maintain
existing scenic vistas. These include policies relating to the preservation of existing
neighborhoods, and the implementation of development standards to reduce impacts from new or
redeveloped projects on adjacent lands. Further, the City will continue to implement its Zoning
standards, which limit building height, and control mass and scale. Finally, the Sustainable
Community Element contains policies geared to high quality design in harmony with the natural
Terra Nova/La Quinta General Plan EIR
Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
III-5
environment, as well as the preservation of natural resources. The policies and programs
contained in that Element will also limit the potential impacts on scenic vistas resulting from
implementation of the General Plan Update. As a result, impacts on scenic vistas caused by
implementation of the General Plan Update, will be less than significant.
Scenic Resources Impacts
Scenic Resources includes trees, rock outcroppings, and historic buildings that are visible from a
state scenic highway. Currently, there are no state scenic highways that run through La Quinta or
the Sphere of Influence. Therefore, impacts to scenic resources along a state scenic highway will
be less than significant.
As discussed in more detail in the Cultural Resources Section, there are a number of recorded
historic-period buildings in the Planning Area. New development has the potential to impact
these structures. The General Plan includes policies protecting historic structures, and assuring
that these structures are assessed and protected, where necessary, if development is proposed. In
addition, impacts and mitigation measures associated with cultural resources are discussed
further in Section III-E of this document. The policies of the General Plan, and mitigation
measures included in Section III-E will assure that impacts associated with historic buildings will
be less than significant.
Visual Character Impacts
The existing visual character of the Planning Area includes the existing look, feel, and quality of
urbanized and natural areas. As described above, the Planning Area is currently characterized as
both urban and rural. The incorporated portions of the Planning Area are predominantly urban,
while the Sphere of Influence is predominantly rural. The General Plan Update has the potential
to cause significant impacts on the existing visual character of the area, especially in the Sphere
of Influence.
Existing development within the City consists of small scale and lower density residential,
commercial, office, public facilities, golf courses, parks and open space. Buildings tend to be
low-rise structures, which preserves views of the surrounding mountains from private and public
lands. An interconnected street system provides accessibility throughout the City limits. For the
most part, streets are developed with sidewalks, curbs, and gutters. Landscaping along public
right-of-ways provides visual relief from the built environment and enhances the visual character
of the community.
The General Plan Update does not propose changes in land use intensities or densities, insofar as
no new land use designations are being considered. Policies and programs in the General Plan
Update are consistent with the existing character of development in the City, and do not propose
intensification or densification of the City or Sphere. Streets will continue to be developed with
curb, gutter, and landscaping to improve visual character along public right-of-ways. Visual
character impacts within the City, therefore, are expected to be less than significant.
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III-6
The visual character of the Sphere is currently more rural than that within the City’s limits, with
very low-density ranch homes, small subdivisions, farms, polo fields, and vacant land. The
General Plan Update does not change the land use designations within this area, and includes a
requirement for master planning of the area prior to annexation. New development in the area
will be governed by this master plan if these lands are annexed to the City. As stated in the
General Plan Update, the master plan is to reflect the character of the area. This requirement will
result in development consistent with this character, which will serve to preserve the visual
character of the area.
As development occurs, new and expanded streets will also develop throughout the Sphere of
Influence, and existing rural roads will be widened and developed with new sidewalks, curbs,
and gutters. The development standards for these streets will include parkway landscaping, trails
and sidewalks, as is required throughout the City, if these lands are annexed. The development
standards will be set in the proposed master plan, which must be developed to reflect community
character. The General Plan Update will therefore have less than significant impacts on the
visual character of the Sphere of Influence.
Light and Glare Impacts
Light and glare impacts are associated with increased urbanization. Within the City limits, the
majority of lands are developed, and daytime and nighttime skies are already affected to a
limited extent by light and glare. The adoption of the General Plan Update will facilitate similar
development patterns in the City to those that exist today. Further, the General Plan Update
maintains policies and programs currently in effect that limit lighting, and the City’s Municipal
Code prohibits light spillage onto neighboring properties. Therefore, implementation of the
General Plan Update will have a less than significant impact on light and glare impacts within
the City.
Build out of land uses proposed for the Sphere will increase the light and glare in this area. Dark
skies will diminish with more traffic, buildings, street lights and indoor illumination. The City
Outdoor Lighting Ordinance (Section 9.100.150 of the Municipal Code) provides regulations for
reducing light and glare caused by new development. The General Plan Update maintains
policies and programs to preserve low lighting levels and the Outdoor Lighting Ordinance, and
requires all future development to develop according to these regulations.
Therefore, implementation of the General Plan Update will have a less than significant impact on
light and glare.
3. Mitigation Measures
The La Quinta 2035 General Plan Update will facilitate continued urbanization in areas that are
undeveloped, but also provides goals, policies and programs to reduce aesthetic impacts
associated with new development. The City’s land use pattern will not change due to the Update,
and the Land Use and Sustainable Community Elements will control the mass, scale and bulk of
new projects and redeveloped sites. Impacts associated with aesthetics are expected to be less
than significant, and no mitigation measures are required.
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III-7
Agricultural Resources B.
Introduction and Background
The General Plan Planning Area has soils and topography suitable for agricultural production.
The Riverside County Important Farmland Map of 2008 has designated areas within the
Planning Area as being important farmland, particularly within the eastern Sphere. Currently,
however, farming in the eastern Sphere is scattered, and much of the lands remain vacant or
fallow. This section assesses impacts on agricultural resources from future growth and
development resulting from the General Plan Update.
Thresholds of Significance/Criteria for Determining Significance
Article 5, Section 15064 of the CEQA Guidelines provides guidance for determining the
significance of the environmental effects caused by a project. Appendix G of the CEQA
Guidelines provides a list of environmental factors that potentially may be affected by
completion of a project. The La Quinta General Plan Update would have a significant effect on
Agricultural Resources if it is determined the General Plan Update would:
a) Convert Prime Farmland, Unique Farmland, or Farmland of Statewide Importance, as
shown on the maps pursuant to the Farmland Mapping and Monitoring Program of
the California Resources Agency, to non-agricultural use.
b) Conflict with existing zoning for agricultural use, or a Williamson Act Contract.
c) Involve other changes in the existing environment, which, due to their location or
nature, could result in conversion of Farmland, to non-agricultural use.
1. Existing Conditions
Agriculture has been a major source of economic activity in the Coachella Valley since the turn
of the 20th century. The Valley provides excellent soils, flat topography, abundant sunshine, and
available water resources, making it a contributor to the State’s agricultural production. The date
palm was introduced to the Valley, and has historically been a staple crop for the region. Other
crops, such as grapes, citrus, vegetables, turf production and ornamentals have also been farmed
in the region. Land available for agricultural production continues to be threatened by increased
urbanization. Since World War II, the Coachella Valley has increased in popularity as a resort
destination, and become home for permanent residents, winter visitors, and the associated
commercial development required to support these households.
La Quinta has experienced the same growth patterns experienced by other nearby cities in the
Coachella Valley. The Sphere of Influence is more rural, with scattered farms, nurseries, and
very low density development. Much of the farming in this area, however, has ceased and the
area remains vacant land. Future development on these vacant lands will be more suburban in
nature.
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Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
III-8
Existing Agricultural Land Uses in the Planning Area
Agricultural uses in the General Plan Update Planning Area are located primarily within the
Sphere of Influence, however a few small citrus groves are located within City limits.
Undeveloped portions of incorporated La Quinta and the Sphere are located in areas designated
as Prime Farmland, Farmland of Statewide Importance, Unique Farmland or Lands of Statewide
Importance, according to the Riverside County Important Farmland Map of 2008. The map was
compiled by the Farmland Mapping and Monitoring Program, under the California Department
of Conservation. 1 In 2008, there were approximately 1,700 acres of important agricultural land
located in the City, and 7,391 acres in the Sphere of Influence, for a total of 9,091 acres. A
description of each classification is found below.
Prime Farmland
Prime Farmland is defined as land with quality soil and moisture supply that allows for
production of high yield crops when managed by modern farming methods. These lands are best
suited for producing food crops, feed, forage, fiber, and oilseed crops. The best use of the land is
for cropland, pastureland, rangeland, and forestland, however urban uses are not recommended.2
Prime Farmland is the largest category of farmland found within the Planning Area. According
to the Important Farmland Map of 2008, approximately 5,424 acres, or 66% of total land in the
Sphere of Influence are designated Prime Farmland. Within the City Limits, 457 acres are
designated as Prime Farmland.3
Farmland of Local Importance
Farmland of Local Importance represents the second largest share of farmland within the
Planning Area. These lands have the soil quality and characteristics of Prime Farmland or
Statewide Important Farmlands, but lack available irrigation water. These lands may produce
crops important to Riverside County, but are not listed as Unique Farmland Crops.4
The Sphere has approximately 1,832 acres of land under this category, which represents
approximately 22% of total land within the Sphere of Influence. Within the City Limit,
approximately 1,214 acres are designated as Farmlands of Local Importance.5
1 “Riverside County Important Farmland 2008”, prepared by California Department of Conservation, Division of
Land Resource Protection, prepared September 2009. 2 Ibid. 3 As provided by City of La Quinta Planning Department through Riverside County Important Farmland GIS
Data, http://redirect.conservation.ca.gov/DLRP/fmmp/county_info_results.asp. 4 “Riverside County Important Farmland 2008”, prepared by California Department of Conservation, Division of
Land Resource Protection, prepared September 2009. 5 As provided by City of La Quinta Planning Department through Riverside County Important Farmland GIS
Data, http://redirect.conservation.ca.gov/DLRP/fmmp/county_info_results.asp.
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Unique Farmlands
Unique Farmlands represents the third largest type of farmland in the General Plan Update
Planning Area. This type of farmland has reduced soil quality or characteristics from Prime
Farmland or Statewide Important Farmlands, but can still be used for high value food and fiber
crops. These lands are capable of producing crops such as citrus, olives, and avocados.6
The Sphere of Influence has approximately 133 acres designated as Unique Farmlands, which
includes the nurseries in the northern Sphere of Influence. The City Limits has 29 acres
designated as Unique Farmland.
Statewide Important Farmlands
Statewide Important Farmlands represent the smallest share of farmland in the La Quinta
General Plan Update Planning Area. These lands are similar to Prime Farmlands, however do not
exhibit as good soil as Prime Farmland. Statewide Important Farmland still has a good
combination of physical and biological characteristics for producing similar crops as Prime
Farmlands, and is available for cropland, pastureland, rangeland, or forestland.7
There are minimal amounts of land considered Statewide Important Farmlands. The Sphere of
Influence has only 1.98 acres of Statewide Important Farmlands, and the City Limit has no
acreage designated as Statewide Important Farmlands.8
Williamson Act Lands
Lands under the Williamson Act, or California Land Conservation Act, are agricultural lands that
allow special tax assessment. These lands are taxed on the basis of agricultural production rather
than market value. The goal of the Williamson Act is to protect agricultural land from being sold
for development. 582 acres of land with Williamson Act contracts are located within the Sphere
of Influence. Based on 2008 Riverside County data, approximately 218.9 acres were in renewal,
and 363 acres were in non-renewal.9 Non-renewal means the farmland reverts back to market
conditions and can be sold at fair market value. Farmland in non-renewal status generally
indicates agricultural land will be developed to non-agricultural land uses.
6 “Riverside County Important Farmland 2008”, prepared by California Department of Conservation, Division of
Land Resource Protection, prepared September 2009. 7 “Riverside County Important Farmland 2008”, prepared by California Department of Conservation, Division of
Land Resource Protection, prepared September 2009. 8 As provided by City of La Quinta Planning Department through Riverside County Important Farmland GIS
Data, http://redirect.conservation.ca.gov/DLRP/fmmp/county_info_results.asp.
9 As provided by City of La Quinta Planning Department through Riverside County Important Farmland GIS
Data, http://redirect.conservation.ca.gov/DLRP/fmmp/county_info_results.asp.
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2. Project Impacts
Conversion of Designated Farmland Types
Implementation of the La Quinta 2035 General Plan will facilitate urban development on lands
designated as Prime Farmland, Farmland of Statewide Importance, Unique Farmland, and
Farmlands of Local Importance. The designation is based on soil types, climatic conditions and
access to irrigation, and does not consider the urban environment in which these lands may
occur. As mentioned above, approximately 9,091 acres, or 29% of the General Plan Update
Planning Area, is designated agricultural lands of statewide or local importance according to the
Riverside County Important Farmland Map of 2008. There were approximately 1,700 acres of
important agricultural land located in the City, and 7,391 acres in the Sphere of Influence. The
1,700 acres located within the City limits are not in agricultural production, and have been
designated for urban uses for some time. Because these lands are located within the City limits,
their loss has generally already occurred, and no significant impact will result.
Implementation of the General Plan Update does not require landowners to immediately convert
farmland to new land uses. However, new development proposed will be required to develop
according to new land use designations. As a result, agricultural lands will be affected by new
growth and development. There are currently over 545,000 acres of important farmland in
Riverside County10. The 7,391 acres of land designated as important farmland represents 1.3% of
the total important farmland in the County. The eventual loss of these lands will not significantly
impact agriculture in the region.
Land uses within the eastern Sphere of Influence are currently governed by the County’s Vista
Santa Rosa Community Plan, which allows for both residential and agriculture related uses.
These lands will continue under the jurisdiction of the County of Riverside until the completion
of master planning for the area. The General Plan Update requires that the master planning
consider the area’s character. This is likely to include very low intensity development, and
agricultural or ranching uses. Further, the City’s Zoning Ordinance includes an
Agricultural/Equestrian Overlay which applies to all lands in the Sphere. This overlay was
specifically designed to allow for the preservation of agricultural and ranching uses in the Sphere
area. No change to this Overlay is proposed, and the standards and land uses permitted in the
Overlay would continue to apply to projects if they were annexed to the City.
Conflicts with Agriculture Zoning
Current zoning standards in the City provide for Very Low Density residential, which allows
equestrian and ancillary agricultural uses on large residential properties. The Very Low Density
Residential zone was established as a transition zone between urban uses within the City Limits
and the agricultural lands within the Sphere of Influence. These uses allowed in the Very Low
Density Residential zone, however are generally not associated with large commercial
agricultural production. The Zoning Ordinance also includes an Agricultural/Equestrian Overlay
10 California Department of Conservation, Division of Land Resource Protection. 2008-2010 Land Use Conversion
inventory.
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which applies to all lands in the Sphere. This overlay was specifically designed to allow for the
preservation of agricultural and ranching uses in the Sphere area. The zoning designations will
remain, and the General Plan Update will have less than significant impacts on agricultural
zoning in the City.
The eastern Sphere of Influence is currently under Riverside County jurisdiction, and will
continue to abide by the County’s zoning standards. City standards will apply only if these lands
are annexed into the City of La Quinta. The County’s Vista Santa Rosa Community Plan assigns
a variety of land uses within four planning areas. One of these planning areas includes a
proposed Village Center, and includes land uses such as Mixed-Use, High Density Residential,
Medium Density, and Medium High Density Residential. The majority of lands in the Vista
Santa Rosa Community, however, are designated Low Density Residential, Very Low Density
Residential and Estate Density Residential. Small agriculture uses and equestrian related uses are
permitted to continue in these low-density land use designations.11
The La Quinta General Plan Update designates the eastern Sphere of Influence primarily as Low
Density Residential, and requires the preparation of a master plan prior to annexation. The
master plan is further required to reflect the character of the area. Annexation to the City cannot
occur without the completion of this master plan. Based on the character of the area, it can be
expected that the master plan will contain provisions for equestrian and agricultural facilities,
and that agricultural uses would remain within the land use mix of the area. Further, the
Agricultural/Equestrian Overlay currently in effect under the City’s Zoning Ordinance will
remain upon adoption of the General Plan. The Overlay allows and protects agricultural and
equestrian activities in the Sphere, should any portion of these lands be annexed in the future. As
a result, impacts associated with agricultural zoning would be expected to be less than
significant.
Williamson Act Lands
In 2008, there was approximately 582 acres of land under Williamson Act Contract in the eastern
Sphere of Influence, of which approximately 218.9 acres were in renewal, and 363 acres were in
non-renewal. The program is voluntary, and landowners enter contracts with initial term of up to
ten years. Based on the acreage currently in non-renewal, the general trend in the region has been
to remove lands from Williamson Act contracts. The adoption of the General Plan Update will
have no impact on these contracts, insofar as they are entirely controlled by the land owners.
Since all contracts currently occur within the Sphere, which is not currently within the City’s
jurisdiction, the General Plan Update will have no immediate impact on these contracts. In the
long term, however, if the Sphere were to be annexed, the land owners would have the ability to
cancel their contracts and develop their land in more suburban land uses, if the master plan were
to so designate these lands. Conversely, nothing in the General Plan Update requires or mandates
the termination of these contracts, and impacts associated with Williamson Act contracts will be
less than significant.
11 “Vista Santa Rosa Community Land Use Concept Plan”, County of Riverside Planning Department, June 17,
2008.
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Conversion of Farmland to Non-agriculture Uses
The implementation of the General Plan Update will facilitate development on lands currently
used for agriculture in the Sphere of Influence. The General Plan Update does not mandate that
landowners terminate agricultural production, but provides regulations when development does
occur on these lands. As previously stated, the General Plan Update includes the master planning
of the Sphere, where agricultural activities occur. The master plan is required to consider and
include community character, and may include agriculture as an allowed land use. Finally, none
of the policies, programs or land use designations of the General Plan Update will apply to any
of these lands if they are not annexed to the City. As a result, adoption of the General Plan
Update will have a less than significant impact on the conversion of farmland to non-agricultural
uses.
3. Mitigation Measures
The General Plan Update will facilitate continued urbanization in areas that are undeveloped and
used for agriculture. The General Plan Update will not directly require conversion of farmland to
non-agricultural uses, however indirect pressures may encourage agricultural landowners to sell
or develop the land. The following mitigation measures will reduce impacts associated with the
conversion of agriculture land to nonagricultural uses.
1. Prior to lands under Williamson Act contract being annexed into the City of La Quinta,
the City shall coordinate with property owners, County of Riverside, and appropriate
state agencies to assure transfer of Williamson Act contracts to the City.
2. The master plan for the Vista Santa Rosa area will incorporate the area’s agricultural
character.
3. New development will be required to provide buffers adjacent to existing agricultural
lands.
4. Incorporate date palms, citrus trees, or other important crops into landscape plans for
open space, right-of-way landscaping, and parks to the greatest extent possible.
Mitigation Monitoring and Reporting
A. New development proposals shall be reviewed by the Planning Department to assure that
master planning and development proposals provide buffering between agricultural lands and
urban land uses.
Responsible Parties: Planning Department, developers, affected landowners.
B. Work with the Department of Conservation and the Farmland Mapping and Monitoring
Program to update the Riverside County Important Farmlands Map to reflect new urban
development and available farmland with General Plan Update Planning Area.
Responsible Parties: Planning Department, Department of Conservation, County of
Riverside
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Air Quality and Greenhouse Gases C.
Introduction
This section of the EIR addresses potential impacts associated with air quality and greenhouse
gas emissions that may arise from implementation of the General Plan Update. The existing air
quality and greenhouse gas conditions, forecast emission projections within City limits and
Sphere of Influence are described, and the potential impacts relating to changes from the
previously approved General Plan are assessed.
Thresholds of Significance/Criteria for Determining Significance
The following thresholds or criteria are derived from Appendix G of the CEQA Guidelines, and
are used to determine the level of potential effect. The significance determination is based on the
recommended criteria set forth in Section 15064 of the CEQA Guidelines. For analysis purposes,
build out of the La Quinta General Plan would have a significant effect on air quality emissions
if it is determined that the project will:
a) Conflict with or obstruct implementation of the applicable air quality plan.
b) Violate any air quality standard or contribute substantially to an existing or projected air
quality violation.
c) Result in a cumulatively considerable net increase of any criteria pollutant for which the
project region is non-attainment under an applicable federal or state ambient air quality
standard (including releasing emissions which exceed quantitative thresholds for ozone
precursors).
d) Expose sensitive receptors to substantial pollutant concentrations.
e) Create objectionable odors affecting a substantial number of people.
f) Generate greenhouse gas emissions, either directly or indirectly, that may have a
significant impact on the environment.
g) Conflict with an applicable plan, policy or regulation adopted for the purpose of reducing
the emissions of greenhouse gases.
South Coast Air Quality Management District
The South Coast Air Quality Management District (SCAQMD or District) has established
thresholds for certain criteria pollutants. Based on the District’s emission thresholds for criteria
pollutants, any project would be considered to have significant impacts to air quality if the daily
emissions exceed the values shown in the table below during construction or operation:
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Table III-1
Emissions Thresholds for SCAQMD
Criteria Pollutant Daily Threshold (pounds)
Carbon Monoxide (CO) 550
Oxides of Nitrogen (NOx) 100
Volatile Organic Compounds (VOC) 75
Oxides of Sulfur (SOx) 150
Particulate Matter (PM10) 150
Particulate Matter (PM2.5) 55
Source: SCAQMD daily thresholds for construction and operation within the Coachella
Valley, March 2009.
In order to protect sensitive receptors from elevated concentration of pollutants, SCAQMD has
developed methodology to assist lead agencies in analyzing localized air quality impacts from
individual projects. Localized significance thresholds (LST) are not applicable to regional
projects, such as this General Plan, but can be considered for project specific development
proposals. The use of LST’s by local governments is voluntary and is to be implemented at the
discretion of the lead agency. The SCAQMD’s Final Localized Significant Threshold
Methodology, revised July 2008, should be referenced for additional information on LST’s.
Greenhouse Gas Emissions
In addition to the thresholds criteria set forth under Appendix G in the CEQA Guidelines,
consistency with Assembly Bill 32 and Executive Order S-3-05 are also considered in order to
make a significance determination for greenhouse gas emissions. Briefly, AB 32 was adopted in
2006 and requires the Air Resources Board (ARB) to develop regulation on how the state will
combat global warming. The goals of AB 32 are to achieve a statewide GHG emission reduction
to 1990 levels by 2020. The Executive Order calls for a statewide GHG emission reduction to
80% below 1990 levels by 2050. For analysis purposes emissions of greenhouse gases from
implementation of the proposed General Plan Update for the City of La Quinta would be
considered significant if the Plan were to interfere with the objectives of AB 32 and S-3-05.
In order to protect air quality locally and contribute to the State mandate to reduce air quality
emissions, the City of La Quinta has prepared a Greenhouse Gas Reduction Plan that is
consistent with the goals of AB 32 and S-3-05.
SCAQMD Interim Thresholds for Greenhouse Gases
In 2008, the SCAQMD established interim significance thresholds for GHG emissions and
published a guidance document for analysis. For the purposes of determining whether or not
GHG emissions are significant, project emissions are to include direct, indirect, and, to the extent
information is available, life cycle emissions during construction and operation. The interim
thresholds are based on a series of Tiers, under which projects being considered under CEQA
should be analyzed. The analysis of impacts is recommended to use modeling programs readily
available, which at the time of the writing of the guidance document, focused on the URBEMIS
model. Since that time, SCAQMD has completed a new modeling tool, CALEmod, which has
been used for the projection of both criteria pollutant emissions and GHG emissions in this
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document. The SCAQMD guidance document does not provide numerical thresholds for the
analysis of GHG emissions. Rather, it recommends compliance with AB 32 reductions, CARB
reduction percentages, and similar published data. These have been used in this analysis, as
described below.
Conformity
A project is considered to be in conformity with adopted attainment and maintenance plans if the
project adheres to the requirements of the South Coast Air Quality Management Rule Book12 and
Air Quality Management Plan13. Divergence from adopted attainment or maintenance plans
would result in non-conformance, and occurs when a proposed project conflicts with or would
result in a delay of implementation for any attainment or maintenance plan. A project is
conforming if it complies with all applicable District rules and regulations, adopted and
forthcoming control measures, and is consistent with the growth forecasts in the applicable
plan(s) (or is directly included in the applicable plan). Conformity with growth forecasts can be
established by demonstrating that the project is consistent with the land use plan that was used to
generate the growth forecast. A non-conforming project would be one that increases the gross
number of dwelling units, increases the number of trips, and/or increases the overall vehicle
miles traveled in an affected area relative to the applicable land use plan.
1. Existing Conditions
Air quality conditions are a result of the geographic setting and local and regional activities.
Local development and population growth, traffic, construction activities, and various site
disturbances in City of La Quinta result in the emission of air pollutants that affect the local air
quality. Although air pollution is emitted from various sources locally, regional air quality
emissions also have an effect on the local air quality. Activities outside of the Salton Sea Air
Basin (SSAB), in which La Quinta is located, result in the emission of pollutants that make their
way into the SSAB from adjacent air basins, including the South Coast Air Basin.
Climate and Geographic Setting
Air quality in a given locality is a function of the amount of pollutants emitted and dispersed, as
well as the local climatic and geographic conditions, which may reduce or enhance the formation
of pollutants. The City of La Quinta is located in the Coachella Valley, and is subject to weather
conditions that are typical of an inland desert climate. The San Jacinto and Santa Rosa Mountain
Ranges west of La Quinta effectively cut off the region from coastal influences. During the
summer, temperatures exceed 100ºF. In the summer months, daily highs are around 105ºF and
lows are around 75ºF. In the winter, temperatures can drop below 20ºF, although winters are
typically moderate, with daily average temperature highs around 70ºF and lows around 50ºF.
Annual rainfall is typically less than 4 inches on the Valley floor, with higher mountain slopes
receiving increased rainfall with increased elevation. Precipitation often occurs in relatively high
12 South Coast Air Quality Management District Rules and Regulations, Adopted February 4, 1977. 13 “Final 2007 Air Quality Management Plan,” prepared by South Coast Air Quality Management District, June
2007.
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III-16
volumes in short duration, and results in stormwater runoff with considerable sediment
deposition on the Valley floor.
The City of La Quinta is subject to high intensity wind events year round. During fall and winter
months, high-pressure systems from the north can conflict with low-pressure systems from the
south, and create a condition known as the Santa Ana winds, which can blow for multiple days at
high speeds. These strong winds sweep up, suspend and transport large quantities of sand and
dust, reducing visibility, damaging property and constituting a significant health threat.
Air Quality Management and Regulation
The federal and California Clean Air Acts regulate air quality management and establish air
quality standards. The United States Environmental Protection Agency (EPA) established the
National Ambient Air Quality Standards (NAAQS) for managing criteria air pollutants in 1971.
The California Clean Air Act (CCAA) became effective on January 1, 1989 and mandated
health-based air quality standards for criteria pollutants at the state level. The California Air
Resources Board (CARB) developed state standards, which are generally more stringent than
federal standards, particularly in regard to carbon monoxide and particulate matter.
State Implementation Plans (SIP) regulate regional air quality by requiring management districts
to develop strategic plans to meet the federal and state ambient air quality standards by the
deadlines specified in the federal Clean Air Act (CAA) and emission reduction targets imposed
by the California Clean Air Act. The Final 2007 AQMP, prepared by SCAQMD, satisfies the
State Implementation Plan requirements of the Clean Air Act.14
The Coachella Valley has become eligible for re-designation as being in attainment due to the
annual average PM10 concentrations meeting the revoked federal standard. The peak 24-hour
average PM10 concentrations have also not exceeded the current federal standard (150 µg/m3).
On February 25, 2010 the California Air Resources Board approved the Coachella Valley PM10
Redesignation Request and Maintenance Plan from serious non-attainment to attainment for the
PM10 National Ambient Air Quality Standard under CAA Section 107.
The SCAQMD is voluntarily requesting that EPA re-designate the Coachella Valley portion of
the SSAB from “Serious” non-attainment to “Severe-15” and extend the attainment date of the 8-
hour ozone standard to 2019. The District’s proposed control strategy includes two components,
including a strategy for the South Coast Air Basin, and control of locally generated emissions in
the Coachella Valley via regulations at the state and federal level.
Toxic Air Contaminants (TAC)
The US EPA regulates TACs through technology-based requirements that are implemented by
state and local agencies. California regulates TACs through the air toxics program and the Air
Toxics “Hot Spots” Information and Assessment Act.15 The CARB works alongside the Office
of Environmental Health Hazard Assessment (OEHHA) to identify TACs, and adopt Air Toxic
14 “2007 Air Quality Management Plan,” South Coast Air Quality Management District, June 1, 2007. 15 AB 2588.
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III-17
Control Measures (ATCMs) to reduce the identified TACs. Where there are federal standards,
CARB must, at minimum, adopt the standards established by the US EPA.
Criteria Air Pollutants
The following air pollutants are collectively known as criteria air pollutants and are defined as
those pollutants for which established air quality standards have been adopted by federal and
state governments. The following provides a summary description of each criteria pollutant,
detailed information can be found in the Air Quality and Greenhouse Gas Report (Appendix B).
Ozone (O3)
Ozone is a gas formed when byproducts of the internal combustion engine and other urban
processes, particularly nitrogen oxide (NOx) and volatile organic compounds (VOC), react in the
presence of ultraviolet sunlight. It is a pungent, colorless, toxic gas commonly referred to as
smog.
Carbon monoxide (CO)
Carbon monoxide is produced from the partial combustion of fossil fuels. EPA estimates that
85%-95% of all CO emissions come from motor vehicle exhaust. Carbon monoxide contributes
to the production of methane, ozone, and carbon dioxide. It is a colorless, odorless, and tasteless
toxic gas that at high concentrations can contribute to heart disease, anemia, and impaired
psychological behavior.
Nitrogen Oxide (NOx)
Nitric oxide (NO) and Nitrogen Dioxide (NO2) are the primary oxides of nitrogen that are
considered criteria pollutants. NOx emissions are byproducts from the operation of motor
vehicles, power plants, and off-road equipment. Short-term exposure to nitrogen dioxide can
result in airway constriction, diminished lung capacity, and is highly toxic by inhalation.
Sulfur Oxides (SOx)
Sulfur oxides occur naturally from volcanic activity, and are generated as a result of various
industrial processes. The most common sulfur oxide compound is Sulfur dioxide (SO2), which
results from the combustion of high-sulfur content fuels, such as coal and petroleum. Sources
include motor vehicle fuel combustion, fossil fuel power plants, chemical manufacturing plants,
and sulfur recovery plants. Sulfur dioxide acts as an acid, can result in the formation of acid rain,
and is a colorless, odorous gas.
Particulate Matter
Particulate matter of ten microns or smaller in diameter are referred to as PM10, whereas PM2.5
consists of particles smaller than 2.5 microns. Particulate matter (PM) may be from soil and dust,
soot and smoke, or aerosols, and is a byproduct of fuel combustion, tire wear, and wind erosion.
Particles less than ten microns in diameter can enter the throat, nose, and lungs. Fine particulate
matter poses a significant threat to public health and can cause increased respiratory infections,
asthma attacks, and lung cancer.
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Lead (Pb)
Lead occurs in the atmosphere from the manufacturing of batteries, paint, ink, and ammunition.
Excessive exposure to airborne lead can lead to anemia, kidney disease, gastrointestinal
dysfunction, and neuromuscular and neurological disorders.
Volatile Organic Compounds
Volatile Organic Compounds (VOC) are also known as Reactive Organic Gas (ROG). This class
of pollutants have no state or federal ambient air quality standards and are not classified as
criteria pollutants, however they are regulated because they are responsible for contributing to
the formation of ozone. They also contribute to higher PM10 levels because they transform into
organic aerosols when released into the atmosphere.
Air Quality Standards
State and federal governments have each established ambient air quality standards for pollutants
of concern, including the criteria pollutants listed above. The federal government sets primary
standards to protect public health, including the health of sensitive populations, such as
asthmatics, children, and the elderly, and sets secondary standards to protect public welfare,
including protection against decreased visibility, damage to animals, crops, vegetation, and
buildings.
Air quality standards are intended to project sensitive receptors, which are people or land uses
that may be especially subject to respiratory stress and/or significant adverse impacts as a result
of exposure to air contaminants. The ARB designates people with cardiovascular and chronic
respiratory diseases, children under 14, seniors over 65, and athletes as sensitive receptors.
Hospitals, nursing and retirement homes, schools, daycares, playgrounds, parks, athletic
facilities, and residential and transient lodging facilities are all considered sensitive land uses.
The following table shows state and federal (primary) air quality standards. State standards are
generally more restrictive than federal standards.
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Table III-2
State and Federal Ambient Air Quality Standards
State Standards Federal Standards**
Pollutant Averaging
Time
Max.
Concentration
Averaging Time Max.
Concentration
Ozone 1 hour
8 hour
0.09 ppm
0.07 ppm
1 hour
8 hour
0.075 ppm
Carbon Monoxide 1 hour
8 hours
20.0 ppm
9.0 ppm
1 hour
8 hours
35.0 ppm
9.0 ppm
Nitrogen Dioxide
(NO2)
1 hour
AAM
0.18 ppm
0.030 ppm
AAM
0.10 ppm*
0.053 ppm
Sulfur
Dioxide
(SO2)
1 hour
24 hours
0.25 ppm
0.04 ppm
1 hour
24 hours
AAM
.075ppm**
Particulate Matter
(PM10)
24 hours
AAM
50 µg/m3
20 µg/m3
24 hours
AAM
150 µg/m3
Particulate Matter
(PM2.5)
AAM
24 hours
12 µg/m3
35 µg/m3
AAM
24 hours
15 µg/m3
35 µg/m3
Lead 30 day Avg. 1.5 µg/m3 3 month Avg. 0.15 µg/m3
Visibility
Reducing Particles
8 hour
No federal
Standard
No federal
Standard
Sulfates 24 hour 25µg/m3 No federal
Standard
No federal
Standard
Hydrogen Sulfide
1 hour
0.03 ppm
No federal
Standard
No federal
Standard
Vinly Chloride 24 hour 0.01 ppm No federal
Standard
No federal
Standard
Notes: ppm = parts per million; ppb= parts per billion; µg/ m3 = micrograms per cubic meter of air;
AAM = Annual Arithmetic Mean;
Source: California Air Resources Board, 9/08/2010
Source: US EPA, September 2010
* Note that this standard became effective as of January 22,2010.
** Final rule signed June 2, 2010, effective as of August 23,2010
Regional Pollutants of Concern and Monitoring
The above standards are the thresholds by which regional ambient air quality is measured. In the
Coachella Valley air quality has exceeded state and federal standards for ozone and particulate
matter. In order to monitor regional pollutants of concern, the SCAQMD operates and maintains
two regional air quality monitoring stations in Source Receptor Area 30 (SRA 30), including one
at a Palm Springs Fire Station, and one in the City of Indio off of Jackson Street. These
monitoring stations report daily air pollutant concentrations and meteorological conditions.
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The following discussion summarizes the past few years of data collected at the monitoring
stations for PM10, PM2.5, and Ozone. The last 10-years of monitoring data can be seen in the Air
Quality and GHG Report.
PM10 Emissions
Natural sand migration, a process referred to as “blowsand,” generates two types of PM10 emissions: (1) natural PM10, which is produced by direct particle erosion and fragmentation, and
(2) secondary PM10, whereby sand deposited on roadways is further broken up by motor
vehicles, then re-suspended in the air.
PM10 levels in the Coachella Valley are attributed to fugitive dust emissions from grading and
construction activities, agricultural practices, and strong winds. In the past several decades a
concerted and joint effort has been made to limit fugitive dust emissions. SCAQMD establishes
measures to reduce particulate matter, sets forth new measures that could further reduce
particulate matter, and maintains a list of new measures that need further evaluation prior to
implementation. Applicable state code and AQMD Rules, including Rule 403 (Fugitive Dust),
enforce fugitive dust compliance.
The table below shows that the federal 24-hour standard for PM10 has not been exceeded at either
monitoring station within SRA 30. However, PM10 levels continue to exceed state standards
within SRA 30.
Table III-3
PM10 Monitoring Data for the Coachella Valley
Monitoring
Station
Year
Maximum
Concentration
(µg/m3/24hours)
No. (%) Samples
Exceeding 24-hr.
Standards
Annual Average
(µg/m3)
Federal1 State2 AAM3 AGM4
Palm Springs 2007 83 0 (0.0%) 6 (11.0%) 30.5 N/A
2008 73 0 (0.0%) 4 (8.0%) 23.2 N/A
2009 133 0 (0.0%) N/A N/A N/A
2010 145 0.0 0.0 19.4 18.3
2011 397 2.0 0.0 21.7 18.1
Indio 2007 146+ 0 (0.0%) 51 (59.0%) 53.5 N/A
2008 128 0 (0.0%) 25 (22.0%) 39.9 N/A
2009 132 0 (0.0%) N/A N/A N/A
2010 107 0.0 23.9 28.8 29.7
2011 376 2.0 18.6 32.6 35.4
Source: Annual air quality site monitoring reports, prepared by SCAQMD and ARB.
1 = > 150 µg/m3 in 24 hour period;
2 = > 50 µg/m3 in 24 hour period;
3 Federal Annual Average Standard AAM > 50µg/m3 revoked December 17, 2006. State standard is AAM >
20µg/m3
4 State Annual Average Standard = AGM > 20µg/m3
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PM2.5 Emissions
The Coachella Valley is defined as unclassifiable for PM2.5, based on the 2007 State Area
Designations and does not require a State Implementation Plan to demonstrate attainment. The
following table shows that the federal and state 24-hour PM2.5 standard has not been exceeded,
nor has the Federal AAM standard of 15 µg/m3. The AAM state standard of 12 µg/m3 has also
not been exceeded in the past few years.
Table III-4
PM2.5 Monitoring Data for the Coachella Valley
Monitoring
Station Year
Max
Concentration
(µg/m3/24hours)
No. Days
Exceeding 24-hr.
Standards
Annual
Average
(µg/m3)
Federala AAM b, c
Palm Springs 2007 32.5 0 8.5
2008 18.1 0 7.1
2009 21.8 0 6.6
2010 12.8 0 5.9
2011 26.3 0 6.0
Indio 2007 26.7 N/A N/A
2008 21.5 0 8.4
2009 27.5 0 7.8
2010 16.0 0 6.8
2011 35.4 0 7.1
Source: Annual air quality site monitoring reports, prepared by SCAQMD and ARB.
a = > 65µg/m3 in 24 hour period, Federal standard prior to December 17, 2006.
b = > 35 µg/m3 in 24 hour period, Federal standard as of December 17, 2006
c Federal Annual Average Standard = AAM > 15µg/m3
d State Annual Average Standard = AAM > 12µg/m3 as of July 5, 2003.
Ozone Emissions
Although the SSAB has a history of exceeding regulatory ozone standards, the number of days
and months that exceed the federal one-hour standard has dropped steadily over the past three
decades. Under the Federal Clean Air Act, the SSAB is classified as a “severe-15” area, which
must achieve attainment by June 15, 2019.
As previously noted, SCAQMD studies indicate that most ozone is transported to the Salton Sea
Air Basin from the upwind South Coast Air Basin, which contains large metropolitan areas
including Los Angeles. It is difficult to quantify the amount of ozone contributed from other air
basins; however, improved air quality in the Coachella Valley depends upon reduced ozone
emissions in the South Coast Air Basin.
The following table shows that the Palm Springs monitoring site exceeds the 1 hour and 8 hour
federal and state standards more frequently than the Indio site.
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Table III-5
Ozone Monitoring Data
No. Days Standard Exceeded
Stations Year Max. Concentration Federal1 State2
1 Hour ppm 8 Hour ppm 8 Hour 1 Hour 8 Hour
Palm Springs 2007 0.13 0.101 20 29 83
2008 0.11 0.101 20 26 70
2009 0.12 0.098 54 28 74
2010 0.114 0.099 52 20 78
2011 0.124 0.098 49 21 69
Indio 2007 0.11 0.094 6 8 48
2008 0.12 0.092 27 12 44
2009 0.10 0.090 24 6 41
2010 0.100 0.087 19 6 45
2011 0.099 0.090 19 3 42
Source: SCAQMD and ARB Annual Air Quality Data Tables.
1 = > 0.12 and 0.08 parts per million in 1 hour and 8 hour respectively.
2 = > 0.09 and 0.75 parts per million in 1 hour and 8 hour respectively.
Global Warming and Climate Change
According to the Intergovernmental Panel on Climate Change (IPCC), global mean temperatures
have risen 0.74oC between 1906 and 2005; global sea surface temperatures have increased to
depths of 3,000 meters since 1961; sea levels have risen by 0.17 mm since the beginning of the
20th century; and snow and glaciers continue to melt faster than new snow accumulation,
contributing to rising sea levels.
According to the National Oceanic and Atmospheric Administration (NOAA) and NASA
reports, the average surface temperature of the earth has warmed 1oF since the 1970s, and the
earth’s surface is warming at a rate of 0. 29oF per decade. These increases have become known
as global warming.
Industrialization, urban lifestyle, agricultural practices, production and manufacturing and other
human activities result in the emission of greenhouse gas that are contributing to global warming
and climate change, and include carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O),
tetrafluoromethane, hexafluoroethane, sulfur hexafluoride, HFC-23 (fluoroform), HFC-134a (s,
s, s, 2 –tetrafluoroethane), and HFC-152a (difluoroethane).
These gases are termed greenhouse gases due to their shared characteristic of trapping heat, are
responsible for the global average increase in surface temperatures, and for the increase in the
rate of warming. There is a high degree of correlation between the concentration of CO2 and
average temperatures. At the beginning of the industrialized era compared to atmospheric
concentration in 2005, CO2 levels had increased by 35%, methane by 151%, and nitrous oxide by
18%. In 2005, carbon dioxide concentrations in the atmosphere were nearly 380 parts per million
(ppm). Comparatively, prior to the Industrial Revolution, about 250 years ago, CO2 levels were
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278 ppm, and over the past 650,000 years carbon dioxide levels have fluctuated between 180 and
300 ppm, making present day atmospheric CO2 levels substantially greater than at any point in
the past 650,000 years.
Under current projection models given business as usual conditions, carbon dioxide levels are
likely to increase to at least 730 ppm and possibly as high as 1,020 ppm by the year 2100, which
would have a substantial effect on environmental and socio-economic conditions. Although there
is much debate over what the effects of climate change will be, there is a general consensus that
the levels of greenhouse gas emissions need to be reduced in order to and limit air pollution and
minimize the potential impacts of climate change.16
Greenhouse Gases
The following provides a summary description of each greenhouse gas, detailed information can
be found in the Air Quality and Greenhouse Gas Report (Appendix B).
Carbon Dioxide (CO2)
Sources of carbon dioxide include the decomposition of dead organic matter, respiration of
bacteria, plants, animals and fungus, evaporation from oceans, volcanic out gassing, and from the
combustion of coal, oil, natural gas, and wood. Carbon dioxide is removed from the air by
photosynthesis, dissolution into ocean water, transfer to soils and ice caps, and chemical
weathering of carbonate rocks.
Methane (CH4)
Methane is released from low oxygen environments, the combustion of fossil fuels, and burning
biomass. Methane remains in the atmosphere for approximately 9-15 years and is a more
efficient absorber of radiation compared to CO2.
Nitrous Oxide (N2O)
Sources of nitrous oxide include releases from microbial processes in soil and water, including
those reactions that occur in fertilizer containing nitrogen, industrial processes, such as fossil fuel
fired power plants, nylon production, nitric acid production, and vehicle emissions. Nitrous oxide
can be transported into the stratosphere, deposited on the Earth’s surface, and converted to other
compounds by chemical reaction.
Halons
Halons are compounds consisting of bromine, fluorine, and carbon and are agents most typically
found in fire extinguishers. Halons have been identified as to contribute to ozone-depletion and
are known greenhouse gases. Halon production in the United States ended in 1993.
16 “Working Group III Contribution to the Intergovernmental Panel on Climate Change Fourth Assessment
Report, Climate Change 2007: Mitigation of Climate Change,” prepared by the Intergovernmental Panel on
Climate Change, May 2007.
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Chlorofluorocarbons
Chlorofluorocarbons (CFCs) are primarily used in air conditioners and refrigerators. They are
also used as solvents to clean electronic microcircuits. Federal regulations require service
practices that maximize recycling of ozone-depleting compounds during servicing and disposal
of air-conditioning and refrigeration equipment.
Hydro-chlorofluorocarbons
HCFCs are similar to CFC’s, are generally used in aerosols and refrigerants, but break down
more quickly in the atmosphere and are more chemically reactive due to their hydrogen
component. HCFC’s affect stratospheric ozone, but to a much lesser extent than CFCs.
Climate Change Regulation
The California Global Warming Solutions Act of 2006 (AB 32) has been passed in order to
comprehensively limit greenhouse gas emissions (GHG) at the state level by establishing an
annual reporting program of GHG emissions for significant sources and sets emissions limits to
cut the state’s GHG emissions to 1990 levels by 2020. On June 1, 2005 Governor Arnold
Schwarzenegger issued executive order S-3-05, which calls for reduction in GHG emissions to
1990 levels by 2020 and for an 80 percent reduction below 1990 levels by 2050.
In 2004 the State of California generated 492 million metric tons of carbon dioxide equivalent
(gross). Although the state’s population grew by 16 percent between 1990 and 2004 GHG
emissions were reduced by 9.7 percent. GHG emission reductions are attributed to energy
conservation measures such as use of energy efficient appliances and building materials that are
prescribed under Title 24 of the California Building Code.
AB 32 was adopted by the state legislature in 2006, and set in motion a statewide effort to
achieve reductions in greenhouse gas emissions through regulatory and market mechanisms. It
sets forth a program to achieve 1990 emission levels by 2020 and requires CARB to proclaim
1990 GHG emissions and develop a Scoping Plan that can be implemented by January 1, 2012.
CARB has reported that 1990 GHG levels were 427 million metric tons (MMT) for the state of
California. The Scoping Plan, adopted on December 11, 2008, includes measures like a cap and
trade program, green building strategies, recycling and waste reduction, and Voluntary Early
Actions and Reductions. CARB has released reduction requirements for regions throughout the
State.
California SB 375 was signed by the Governor in September 2008 and is intended to at least in
part implement greenhouse gas reduction targets set forth in AB 32. The bill encourages regional
land use planning to reduce vehicle miles traveled and requires jurisdictions to adopt a
sustainable communities strategy.
The CEQA Guidelines now require the analysis and mitigation of impacts associated with
greenhouse gases. The Guidelines require that all feasible mitigation measures be considered,
including the adoption of plans and programs to reduce emissions of future development
projects. The City’s Greenhouse Gas Reduction Plan has been prepared to address these
requirements.
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Greenhouse Gas Reduction Plan
The City of La Quinta has completed a Greenhouse Gas Inventory and has prepared a
Greenhouse Gas Reduction Plan as part of this General Plan Update. The intent of the
Greenhouse Gas Reduction Plan is to set goals, policies, and programs that will result in the
reduction of greenhouse gas emissions to targets identified in the Plan that meet the State’s
mandates. The provisions of the Plan have been included in the analysis of air quality and
greenhouse gas impacts provided below.
2. Project Impacts
The potential for air quality impacts in the La Quinta Planning Area will increase with
implementation of the proposed General Plan Update. Air pollutants will be generated from a
variety of activities occurring within the Planning Area, including grading and construction,
vehicle emissions, and daily operations. Emissions generated by vehicular traffic are projected to
be the greatest source of air pollutants. The use of natural gas and electricity for operation of
existing and new buildings and structures will also result in the emission of air pollutants.
Major sources of pollutants associated with build out of the General Plan are quantified and
described in detail in the Air Quality and Greenhouse Gas Report, which can be found in
Appendix B of this EIR. The following discussion summarizes the major findings of the Air
Quality Analysis and makes a significance determination based on CEQA criteria and SCAQMD
thresholds.
Compliance with SCAQMD AQMP
As mentioned above, the City of La Quinta is subject to the 2007 Air Quality Management Plan,
prepared by the South Coast Air Quality Management District. The proposed La Quinta General
Plan Update has the potential to increase development intensities and the City’s build out
population compared to the 2002 General Plan, upon which population projections for the 2007
AQMP were based. The size and composition of the population has a direct effect on the amount
of air quality emissions. The typical trend being that an increase in population results in a
correlated increase in the level of air quality emissions. However, state legislation, such as SB
375 and AB 32, as well as regional and local programs and policies have shown that with proper
land use planning, adherence to building codes, especially Title 24, and opportunities for
alternative modes of transport, this trend can be reversed.
Under business as usual conditions, the proposed General Plan Update has the potential to
conflict with or obstruct implementation of the adopted 2007 Air Quality Management Plan
prepared by SCAQMD due to the increased densities proposed in the eastern Sphere, and the
associated population projections. Although the proposed population projections for the General
Plan Update within City limits are comparable to those set forth under the 2002 General Plan, the
population for the Sphere of Influence is projected to nearly double. The projected increase in the
population size within the Sphere of Influence as set forth in the General Plan Update, when
compared with the Riverside County General Plan, has the potential to conflict with or obstruct
implementation of the Air Quality Management Plan.
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Implementation of mitigation measures, including adherence to the GHG Reduction Plan are
expected to substantially reduce emissions of air quality pollutants and reduce the per capita
emission contribution. Therefore, it is expected that with mitigation measures, the General Plan
Update will be consistent with the Air Quality Management Plan and impacts will be reduced.
Air Quality Standards
As mentioned above federal and state air quality standards have been established for several
pollutants. Within the Coachella Valley, ozone and particulate matter concentration have
exceeded air quality standards and are monitored and managed by SCAQMD.
The City of La Quinta requires best management practices (BMPs), adherence to building codes
and standards, and the adoption of dust control plans for all new development. In addition,
SCAQMD has established several programs specifically designed to limit the emission of ozone
and the generation of particulate matter. Adherence to established and forthcoming programs and
policies set forth by SCAQMD will assure that in and of itself, the proposed General Plan
Update will not violate any air quality standard or substantially contribute to any existing or
projected air quality violation.
Air Quality Emission Projections
Construction and operation of land uses set forth in the General Plan Update are expected to
result in the generation and emission of air pollutants. The following quantifies these emissions.
Construction
The General Plan Update has the potential to result in the development of 10,718 currently
vacant acres, including residential, commercial, recreational open space, major community
facilities, and street rights-of-way. As the General Plan is expected to build out over a 25-year
period, this corresponds to an average annual build out of approximately 428.72 acres per year,
1,153 dwelling units, and 251,529 square feet of retail/industrial development.
For analysis purposes, emissions from construction activities are averaged over the 25-year build
out period to estimate annual emissions. The Table below shows the emission projections for the
average annual development likely to occur under implementation of the General Plan Update.
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Table III-6
Construction Emissions for the Planning Area
(pounds per day)
CO NOx ROG1 SOx PM10 PM2.5
City Limits
Unmitigated 241.90 202.78 906.78 0.24 2,284.59 484.21
Mitigated 241.90 122.28 818.45 0.24 140.89 31.41
SCAQMD Threshold 550.00 100.00 75.00 150.00 150.00 55.00
Significant No Yes Yes No No No
Sphere of Influence
Unmitigated 206.06 172.73 772.45 0.21 1,946.14 412.47
Mitigated 206.06 104.16 697.20 0.21 120.01 26.76
SCAQMD Threshold 550.00 100.00 75.00 150.00 150.00 55.00
Significant No Yes Yes No No No
Planning Area Total
Unmitigated 447.96 375.51 1,679.23 0.45 4,230.73 896.68
Mitigated 447.96 226.44 1,515.65 0.45 260.90 58.17
SCAQMD Threshold 550.00 100.00 75.00 150.00 150.00 55.00
Significant No Yes Yes No Yes Yes
Source: Air Quality and GHG Report, prepared by Terra Nova Planning and Research, June 2012. 1Reactive Organic Gases (ROGs), sometimes referred to as Volatile Organic Compounds (VOC)
With implementation of mitigation measures, air quality emissions from construction activities
within City limits are projected to remain below established thresholds for all criteria pollutants
except for NOx and ROG. The sources of ROG’s during construction include the evaporation of
solvents found in paints, varnishes, primers, and other surface coatings. Even with
implementation of mitigation measures, air quality emissions of NOx and ROG have the potential
to result in significant and unavoidable impacts from construction activities occurring within
City limits.
Construction related air quality emissions from the development of lands within the Sphere of
Influence are projected to exceed established daily thresholds for NOx and ROG, even with
implementation of mitigation measures. Newly adopted and forthcoming fuel standards are
expected to dramatically reduce emissions of NOx. Given the projected levels of NOx, it is
conceivable that emission reductions from full implementation of the off-road diesel fuel
standard will result in reducing emission to below threshold levels. In addition, requiring the use
of the latest available technology and assuring that the construction fleet is properly maintained
and updated will contribute to further limiting emissions. Nonetheless, construction activities
within the Sphere of Influence have the potential to result in significant and unavoidable impacts
to air quality from the emission of NOx and ROG.
Air pollutant emissions from construction activities are considered temporary impacts and will
end once construction is complete. Nonetheless, during construction activities and assuming
simultaneous construction of vacant lands within the Planning Area, the proposed General Plan
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Update has the potential to result in a cumulatively considerable net increase of NOx, ROG, and
PM10. Projections of these criteria pollutants exceed established daily and have the potential to
result in significant and unavoidable impacts for these criteria pollutants.
Operation
Daily activities at operation will result in the emission of air quality pollutants from the use of
electricity and natural gas, and will be emitted from area sources and moving sources. The use of
electricity within the Planning Area results in offsite emissions from the production of electricity.
Although emission associated with electricity do not occur within the physically boundary of the
Planning Area, they are considered as part of the operational impacts from build out of the
General Plan Update. Emissions from natural gas occur from the combustion of natural gas
within the Planning Area for operational activities such as heating and cooling, and cooking.
Area source emissions include the use of consumer products, the application of architectural
coatings, hearth fuel combustion, and fuel used for landscaping purposes. Moving sources
include emissions from vehicles at build out of the General Plan Update.
Electricity and natural gas usage rates were obtained from the utility companies as part of the
inventory effort conducted for the GHG Reduction Plan. Per unit and per square footage usage
rates were calculated based on data provided and said factors were used to project build out
demand under business as usual conditions within the La Quinta Planning Area. The Urbemis
model was used to estimate emissions from area sources and moving sources. Detailed
methodology and assumption used to project build out demands and associated emissions are
described in the Air Quality and GHG Report (Appendix B).
The table below summarizes the projected emissions associated with daily operations within the
Planning Area, at build out, under business as usual conditions. Due to the size and scale of the
City Limits and the Sphere of Influence, air quality emissions for all criteria pollutants (CO,
NOx, SOx, Particulates and ROG’s) are projected to exceed established SCAQMD thresholds at
operation.
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Table III-7
Projected Daily Emissions at
General Plan Build Out
Stationary Source Emissions Moving
Source
Emission
Total
Emissions
SCAQMD
Threshold
Criteria
Electricity Natural
Gas
Area
Sources
All
Vehicles
Total
Lbs./Day
Total
Lbs./Day
City Limits
CO 597.49 219.14 7,044.98 8,471.50 16,333.11 550
NOx 3,435.58 377.96 375.10 788.00 4,976.64 100
SOx 358.50 0.004 18.16 23.00 399.66 150
PM10 119.50 0.71 1,001.99 3,894.00 5,016.19 150
PM2.5 N/a N/a 965.36 763.00 1,728.36 55
ROGs 29.87 28.54 4,112.07 949.00 5,119.48 75
Sphere of Influence
CO 303.96 109.51 5,217.98 4,787.50 10,418.94 550
NOx 1,747.76 209.85 329.45 442.50 2,729.56 100
SOx 182.37 0.002 13.18 13.00 208.56 150
PM10 60.79 0.40 726.75 2,262.00 3,049.94 150
PM2.5 N/a N/a 700.09 443.00 1,143.09 55
ROGs 15.20 15.98 2,984.34 515.50 3,531.02 75
Planning Area Total
CO 901.45 328.65 12,262.96 13,259.00 26,752.05 550
NOx 5,183.34 587.81 704.55 1,230.50 7,706.20 100
SOx 540.87 0.01 31.34 36.00 608.22 150
PM10 180.29 1.10 1,728.74 6,156.00 8,066.13 150
PM2.5 N/a N/a 1,665.44 1,206.00 2,871.44 55
ROGs 45.07 44.52 7,096.40 1,464.50 8,650.50 75
Source: Air Quality and GHG Report, prepared by Terra Nova Planning and Research, June 2012.
For build out of the General Plan Update, air quality emissions have the potential to result in a
cumulatively considerable net increase of CO, NOx, SOx, PM10, PM2.5, and ROG. Projections of
these pollutants exceed established daily thresholds and have the potential to result in significant
and unavoidable impacts.
Sensitive Receptors
The land use plan has been designed to provide a buffer between sources of air quality emissions
and sensitive receptors. Although daily criteria pollutant emission thresholds will be exceeded, it
is expected that state and federal standards for regional pollutants of concern will be unaffected
by the proposed General Plan. The 2007 AQMP has projected that ozone standards will be
achieved by 2018 for the Coachella Valley. With implementation of mitigation measures, the La
Quinta General Plan Update will not interfere with attainment of the 8-hour ozone standard. As
mentioned above, the Coachella Valley is eligible for redesignation as attainment due to the
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annual average PM10 concentrations meeting the revoked federal standard, and since the peak 24-
hour average PM10 concentrations have also not exceeded the current federal standard (150
µg/m3). Thus, the proposed General Plan Update is not expected to expose sensitive receptors to
substantial pollutant concentrations and air quality impacts to sensitive receptors are expected to
be less than significant.
Objectionable Odors
The proposed General Plan Update does not include any land uses that have the potential to
generate objectionable odors. Further, individual projects which may be proposed within the
City, or on Sphere lands if annexed, will be reviewed individually based on their potential to
generate odors under CEQA. Therefore, it is considered unlikely that implementation of the
General Plan Update, including lands within City limits and the Sphere of Influence, would
result in objectionable odors affecting a substantial number of people. The General Plan Update
is expected to have less than significant impacts in regards to odors.
Greenhouse Gas Emissions
Construction and operation of land uses set forth in the General Plan Update are expected to
result in the generation of greenhouse gas emissions. These emissions are characterized below.
Construction GHG Emissions
As mentioned above, construction emissions are based on the ground disturbance and
development of 10,718 acres, including residential, commercial, recreational open space, major
community facilities, and street right-of-ways. Urbemis was utilized to estimate the CO2
emissions that will be generated as a result of construction activities. For analysis purposes, CO2
emissions from annual average construction activities were multiplied by 25 years in order to
estimate the total GHG emissions likely to occur from construction activities. To determine the
amount of CH4 and N2O associated with the CO2 level, a ratio of 0.00006 for CH4 and a ratio of
0.00003 for N2O were assumed, per ton of CO2 emitted. Ratios for CH4 and N2O are pursuant to
figures for diesel operated construction equipment provided in the California Climate Action
Registry General Reporting Protocol, Version 3.1, January 2009. CO2 Equivalence (CO2e) was
calculated by using a global warming potential of 21 for CH4 and 310 for N2O.
The Table below shows the total summary of projected GHG emissions expected to occur from
construction activities of the General Plan Update.
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Table III-8
GHG Emissions from Construction of the General Plan
(metric tons)
CO2 CH4 N2O CO2e
City Limits 94,231.35 5.09 2.56 95,133
Sphere of Influence 80,271.15 4.33 2.18 81,039
Planning Area Total 174,502.49 9.42 4.75 176,172
Source: Air Quality and GHG Report, prepared by Terra Nova, June 2012.
It should be mentioned that projected GHG emissions are conservative in that they represent
emission levels using current factors. New standards for heavy-duty diesel construction
equipment are currently being developed and will be phased in beginning in 2012. Therefore, the
analysis conducted for GHG emissions represents a worst-case scenario assuming the continued
use of current model year or older construction equipment. In practice and as feasible, new
model construction equipment shall be utilized for all construction activities within the La
Quinta Planning Area.
Emissions of GHG’s during construction activities have the potential to either directly or
indirectly result in a temporary impact on the local and regional air quality conditions. GHG
emissions from construction will end once construction activities are complete. Therefore, the
generation and emission of GHG’s from construction are not expected to have a long term or
lasting impact on the environment and impacts to air quality from construction are expected to be
less than significant.
Operational GHG Emissions
The proposed project will result in the emission of greenhouse gases through the combustion of
fossil fuels during operation of vehicles, the generation of electricity at power plants, combustion
of natural gas, and the transportation of water. The following tables shows the projected GHG
emissions from operation at build out of the General Plan Update and includes activities within
City limits and the Sphere of Influence.
Table III-9
GHG Emissions from Operation at General Plan Build Out
(million metric tons)
Electricity
Natural
Gas
Moving
Sources
Water
Transport Total
City Limits 0.479 0.078 0.437 0.011 1.004
Sphere of Influence 0.243 0.044 0.253 0.007 0.548
Planning Area Total 0.722 0.122 0.690 0.018 1.552
Source: Air Quality and GHG Report, prepared by Terra Nova, June 2012.
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Operational activities would result in the generation and emission of greenhouse gases, which
could have significant impacts to air quality locally and regionally. Implementation of the
Greenhouse Gas Reduction Plan is intended to reduce impacts associated with the emission of
greenhouse gases within City limits to levels that are less than significant.
Lands within the Sphere of Influence are currently governed by the County of Riverside and are
not subject to compliance with the La Quinta Greenhouse Gas Reduction Plan. In the event that
the Sphere of Influence continues to be governed by the County jurisdiction, then impacts from
the emission of greenhouse gases are expected to be significant. Were the Sphere of Influence to
be annexed into La Quinta City jurisdiction, then lands would be subject to the Greenhouse Gas
Reduction Plan and compliance with said plan would assure that impacts to air quality from the
emission of greenhouse gases would be reduced to levels below significance.
Greenhouse Gas Reduction Plan
The City of La Quinta has prepared a Greenhouse Gas Reduction Plan as part of the General
Plan. The Greenhouse Gas Reduction Plan quantifies the baseline emissions, projects future
emission levels, and creates a plan to achieve greenhouse gas emission reductions consistent with
AB 32. As such, the targets set forth in the GHG Reduction Plan are to achieve 10% below 2005
emission levels by 2020 and 28% below 2005 levels by 2035.
The La Quinta Greenhouse Gas Reduction Plan identifies 2005 as the base year and estimates
that 460,946 metric tons of CO2e were emitted from community wide activities. With business as
usual conditions the community wide CO2e is projected to be 668,627 metric tons in 2020, and
828,538 metric tons in 2035. In order to achieve targeted reductions, CO2e emission will need to
be reduced by 253,775 metric tons by 2020, and by 496,657 metric tons by 2035. As seen in the
GHG Reduction Plan, implementation of reduction measures will achieve 253,950 metric tons by
2020 and 496,681 metric tons by 2035. As such implementation of the GHG Reduction Plan will
substantially reduce emission levels and assure consistency with state targets.
The La Quinta Greenhouse Gas Reduction Plan identifies 2005 as the base year and estimates
that 9,807 metric tons of CO2e were emitted from government activities. As set forth in the GHG
Reduction Plan under business as usual conditions CO2e emitted as a result of government
activities is projected to be 11,328 metric tons in 2020, and 12,671 metric tons in 2035. In order
to achieve targeted reductions, CO2e emission will need to be reduced by 2,502 metric tons by
2020, and by 5,610 metric tons by 2035. As seen in the GHG Reduction Plan, implementation of
reduction measures will achieve 2,514 metric tons by 2020 and 5,614 metric tons by 2035. As
such implementation of the GHG Reduction Plan will substantially reduce emission levels and
assure consistency with State targets.
The General Plan Update does not conflict with the GHG Reduction Plan or any other policies or
regulations that are intended to reduce the emissions of GHG’s. Rather, the GHG Reduction Plan
has been prepared as part of the General Plan Update process and with the intent to reduce GHG
emission to levels that are consistent with state goals. Adoption and adherence to the GHG
Reduction Plan will assure that emissions of GHG’s from the implementation of the proposed
General Plan are reduced to levels below significance.
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Cumulative Impacts
Global climate change is a cumulative impact by nature. For the most part an individual project
does not generate enough GHG emissions to significantly influence global climate change.
Nonetheless, individual projects may participate in a potential impact through incremental
contribution, combined with the contributions of all other sources of GHG. In assessing
cumulative impacts, it must be determined if a project’s incremental effect is cumulatively
considerable.17 To make this determination the incremental impacts of the project must be
compared with the effects of existing, proposed, and future projects.
For General Plan purposes, individual projects that are consistent with the greenhouse gas
reduction plan will not result in cumulatively considerable impacts to greenhouse gas emissions.
3. Mitigation Measures
In order to mitigate the potential air quality impacts associated with implementation of the
proposed General Plan Update, a comprehensive Greenhouse Gas Reduction Plan has been
prepared. The Greenhouse Gas Reduction Plan is intended to substantially reduce emissions of
criteria pollutants and greenhouse gases generated by activities within the City of La Quinta and
serve as mitigation to reduce emissions. Measures set forth within the Greenhouse Gas
Reduction Plan along with general measures set forth below will mitigate potential impacts to air
quality. However, as illustrated above, emissions associated with operation of land uses at build
out of the General Plan will exceed established thresholds, even when mitigated. Long term air
emission impacts, therefore, will be significant and unavoidable.
The following mitigation measures are required in order to limit air quality emission within the
Planning Area:
1. The City of La Quinta shall adopt and implement a comprehensive Greenhouse Gas
Reduction Plan that is consistent with targeted reductions set forth by the State.
2. As feasible, the newest model heavy-duty construction equipment shall be utilized for
construction activities. The construction equipment fleet shall be updated to include the
latest models; older equipment shall be phased out. Specifically, 2010 and newer diesel
haul trucks (e.g., material delivery trucks and soil import/export) shall be used. If the City
determines that 2010 model year or newer diesel trucks cannot be obtained, it shall use
trucks that meet EPA 2007 model year NOx and PM emissions requirements.
3. To reduce fugitive dust during construction activities, trucks leaving development sites
should be washed off; haul trucks should maintain 2 feet of freeboard or be covered;
equipment should be properly tuned and maintained; and low sulfur fuels should be used
for construction equipment. Effective fugitive dust control measures can substantially
reduce emissions as shown in the Table below.
17 CEQA Guidelines sections 15064(i)(1) and 15130.
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Table III-10
Air Quality Control Methods
PM10 PM2.5 NOx
Apply Soil Stabilizers to Inactive Areas 84% 84%
Replace Ground Cover in Disturbed Areas 5% 5%
Water Exposed Surfaces 3 Times Daily 61% 61%
Reduce speeds on unpaved roads 44% 44%
Use of aqueous diesel fuel 50% 50% 15%
Use of Diesel Particulate Filter 85% 85%
Use of Diesel Oxidation Catalyst1 15%-40%
Source: Urban Emissions Model (URBEMIS2007) version 9.2.4.
1. Emission reductions vary depending on equipment type.
4. To reduce construction-related traffic congestion, developers and contractors shall
configure construction parking to minimize traffic interference, provide a flag person to
ensure safety at construction sites, as necessary, designate onsite travel routes to
minimize impacts to nearby land uses, and schedule operations affecting roadways for
off-peak hours, as practical.
5. Construction equipment shall be staged in locations that minimize impacts to nearby
receptors.
6. La Quinta shall continue to coordinate with CVAG and SCAQMD regarding the
implementation of local and regional air quality programs.
The follow mitigation measures are derived from consensus recommendations for reducing a
project’s contribution to greenhouse gas emissions:
1. Landscaping designs shall consider the use of trees and other vegetation to maximize the
shading of buildings in order to reduce energy requirements for heating and cooling and
provide carbon storage.
2. Desert landscaping techniques shall be utilized, including the use of automated water
efficient irrigation systems and devices.
3. Smart scalping practices shall be encouraged to minimize fugitive dust emissions and
reduce water demands.
4. Building designs shall strive to exceed Title 24 requirements or achieve LEED or Energy
Star standard equivalence ratings or better; buildings shall be equipped with energy
efficient and water conserving appliances and fixtures; building design shall include
natural lighting and ventilation; and light colored “cool” roofs and cool pavement shall be
utilized.
5. New buildings and substantial remodels including new roofs, should be designed to
accommodate rooftop photovoltaic or above parking solar.
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6. Recycling and composting facilities and programs shall be readily available for all new
and existing land uses and every effort shall be made to divert the landfill waste stream.
7. Utilize educational programs and demonstration gardens to inform the public and
businesses of energy and water efficient techniques and sustainable practices.
The following design strategies will reduce reliance on traditional automobiles for transportation:
1. Promote the use of electric vehicles and alternative modes of transport by providing safe
and convenient bicycle, scooter and other non-motorized transport travel lanes, and
parking, as well as preferential plug-in stations for electric vehicle parking.
2. In designing and expanding travel corridors provide for pedestrian and bicycle paths that
interconnect to commercial, recreational, and institutional land uses.
3. Assure all new development has safe and convenient access to public transit routes that
include seated, shaded bus stop areas.
4. Incorporate recreational open space adjacent to or as part of residential land uses.
5. Expand and coordinate a Valley wide signal synchronization system within city limits
and adjacent jurisdictions.
6. Work with CVAG, SCAG and regional transit authorities to work towards more efficient,
region wide travel options.
Mitigation Monitoring and Reporting
A. Building and landscape plans shall be reviewed for energy efficiency and soil stabilization.
Landscapers and landscape-related businesses shall be required to show proof of completion
of the CVAG’ Landscaper Certification Source.
Responsible Parties: Public Works, Engineering, Planning, and Building Departments.
B. A report of air quality complaints and identified problems shall be provided in the annual
review of the General Plan.
Responsible Parties: Public Works, Code Compliance and Planning Department, and
SCAQMD.
C. A report of emission reductions achieved shall be provided in the annual review of the
General Plan.
Responsible Parties: Planning Department and SCAQMD.
D. The City shall conduct review and prepare conditions of approval for all grading and
development permits, as well as required dust control plans to assure that appropriate
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methods and technologies are in place to minimize the emissions of pollutants from the
development activities.
Responsible Parties: Public Works, Engineering, Planning, and Building Departments.
Biological Resources D.
Introduction
This section discusses the biological resources in La Quinta, and assesses impacts on these
resources from future growth and development brought on by the La Quinta 2035 General Plan
Update. It also provides mitigation measures to reduce impacts to important biological resources.
The following discussion is based on the Biological Resources Study prepared by AMEC in
2010.
Thresholds of Significance/Criteria for Determining Significance
The following standards and criteria have been drawn from Appendix G: Environmental
Checklist Form of the CEQA Guidelines. The following factors have been considered to ensure
that the General Plan EIR adequately addresses potential impacts to biological resources that
may result from the development facilitated by implementation of the La Quinta General Plan.
Build out of the proposed General Plan would have a significant impact on biological resources
if it would:
a) Have a substantial adverse effect, either directly or through habitat modifications, on any
species identified as a candidate, sensitive, or special status species in local or regional plans,
policies, or regulations, or by the California Department of Fish and Game or U.S. Fish and
Wildlife Service.
b) Have a substantial adverse effect on any riparian habitat or other sensitive natural community
identified in local or regional plans, policies, regulations or by the California Department of
Fish and Game or US Fish and Wildlife Service.
c) Have a substantial adverse effect on federally protected wetlands as defined by Section 404
of the Clean Water Act (including, but not limited to, marsh, vernal pool, coastal, etc.)
through direct removal, filling, hydrological interruption, or other means.
d) Interfere substantially with the movement of any native resident or migratory fish or wildlife
species or with established native resident or migratory wildlife corridors, or impede the use
of native wildlife nursery sites.
e) Conflict with any local policies or ordinances protecting biological resources, such as a tree
preservation policy or ordinance.
f) Conflict with the provisions of an adopted Habitat Conservation Plan, Natural Community
Conservation Plan, or other approved local, regional, or state habitat conservation plan.
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1. Existing Conditions
A comprehensive biological resources study was prepared for the General Plan Update by
AMEC Earth and Environmental.18 The report is included in Appendix C of this document.
AMEC consultants conducted a literature review that included the California Natural Diversity
Data Base (CNDDB 2010), a variety of botanical and wildlife references pertinent to the
Planning Area, biological surveys prepared by AMEC for projects in or near the planning area
(AMEC 2003), including species accounts, life histories, and distribution and status of covered
species, and a review of the Coachella Valley Multiple Species Habitat Conservation Plan
website (2010). The United States Department of Agriculture, Natural Resources Conservation
Service’s Web Soil Survey data available for La Quinta (NRCS 2010) was referenced to
determine soil types in the Planning Area. AMEC biologists also conducted a field survey of the
General Plan and Area as part of the biological resources assessment.
Regional Biological Setting
The Planning Area is located in a natural environment that displays substantial variation,
including elevations ranging from 190 feet below sea level in the southeastern corner of the
Sphere of Influence, to over 1,700 feet above sea level in the foothills of the Santa Rosa
Mountains. Most of the City and the Sphere of Influence occur on the Valley floor, which is
characterized by hot, dry summers and mild winters. Soil types and the natural habitats that can
be supported in the Planning Area are affected by climate. There are eleven primary soil types
found in the City and Sphere; most of these are sandy in nature, and well drained. Rock and
rubble occur in the Santa Rosa foothills. Soil types in the Planning Area include Carrizo stony
sand, Carsitas Sands, Coachella Sands, Fluvents, Gravel Pits and Dumps, Gilman Sands and
Loams, Indio Loams, Myoma Fine Sands, Rock Outcrop, Rubble Land, and Salton Fine Sandy
Loam. Soil properties in the Planning Area are further discussed in Section III-F, Geology and
Soils.
There are limited areas of naturally occurring habitat in the City and on the Valley floor, as a
result of agriculture and urban development. Lands on the slopes of the Santa Rosa Mountains
have little potential for development and native habitat still occurs. These lands are designated as
Open Space in the existing and proposed General Plans. Elsewhere in the City, vegetation is
primarily comprised of non-native ornamental plants introduced by developers and homeowners.
Natural Communities
The following natural communities occur within the Planning Area. The locations of these are
shown on Exhibit III-1, Vegetation Communities.
18 “City of La Quinta General Plan Update: Biological Resources,” prepared by AMEC Earth & Environmental,
Inc., June 2010.
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Stabilized Shielded Sand Fields
Regionally, Stabilized and Partially Stabilized Desert Sand Fields are those in which sand is
supplied through sand source and sand transport systems. In the Planning Area, these have
generally been interrupted or shielded by barriers such as roads, buildings, and landscaping. The
long-term persistence of stabilized shielded desert sand fields is compromised by the interruption
of the sand source and sand transport system and occur in the Planning Area as Stabilized
Shielded Sand Fields. Most of these areas have been developed for residential and commercial
projects. In La Quinta, this natural community is limited to the northern portion of the PA in the
vicinity of Highway 111, and largely consists of smaller, fragmented parcels heavily disturbed
by their proximity to roads. It includes most of the remaining sand fields south of U.S. Interstate
10 that historically comprised the Big Dune.
Representative plants found in this community include Sand Verbena (Abronia villosa), Fanleaf
Crinklemat (Tiquilia plicata), California Croton (Croton californicus), Four-wing Saltbush
(Atriplex canescens), and Indian Ricegrass (Achnatherum hymenoides). In the Planning Area, no
Stabilized Shielded Sand Fields community has been targeted for conservation in the MSHCP.
The non-native, invasive plant species Sahara Mustard (Brassica tournefortii) poses a serious
threat to this community, as well as to sandy communities throughout the Sonoran and Mojave
Deserts. Although present in the Coachella Valley since the 1920’s, Sahara Mustard has become
increasingly abundant. It has been demonstrated to negatively impact native flora as well as
certain wildlife species, among them the Coachella Valley Fringe-toed Lizard.
Sonoran Creosote Bush Scrub
The most common natural community in the Coachella Valley region is the Sonoran creosote
bush scrub. Dominant plants include Creosote Bush (Larrea tridentata), Burrobush (Ambrosia
dumosa), Brittlebush (Encelia farinosa), and other common desert perennials. Up to 75% of the
vegegation in this community may be represented by wildflowers.
In the Planning Area, this community is primarily found above the shoreline of ancient Lake
Cahuilla, as well as on the lower Santa Rosa Mountain slopes and portions of alluvial fans and
bajadas emanating from the mountains. In these areas it is often intermixed with other plant
communities, including Sonoran Mixed Woody and Succulent Scrub, and with Desert Dry Wash
Woodland.
Sonoran Mixed Woody and Succulent Scrub
Similar to creosote bush scrub, this community is typically more varied and contains a higher
density of plants. It has a sizeable dominance of cacti and other stem succulents, unlike other
Sonoran desert communities in the Planning Area. Typical species include Golden Cholla
(Opuntia echinocarpa), Buckhorn Cholla (Opuntia acanthocarpa), Pencil Cholla (Opuntia
ramosissima), Beavertail (Opuntia basilaris), California Barrel Cactus (Ferocactus
cylindraceus), and Ocotillo (Fouquieria splendens). Creosote bush and other associated
perennial shrubs are also associated with this community, which occurs on alluvial fans and
slopes of the Santa Rosa Mountains.
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Desert Dry Wash Woodland
This community is characterized by open to dense, drought-deciduous, microphyllous woodland
plants as tall as 30 to 60 feet. Members of the pea family are dominant, and may include Blue
Palo Verde (Cercidium floridum), Ironwood (Olneya tesota), and Smoketree (Psorothamnus
spinosus). Desert Lavender (Hyptis emoryi), Cheesebush (Hymenoclea salsola), Catclaw (Acacia
greggii), and Desert Willow (Chilopsis linearis) may also be associated with this community. In
the Planning Area, desert dry wash woodland occurs in association with canyon mouths and
alluvial fans in the Santa Rosa Mountains. It is typical of ephemeral washes, which are subject
to occasional flooding but without consistent surface flows.
Desert Saltbush Scrub
There are a variety of species of saltbush that may occur in this community, which is
characterized by a nearly uniform stand of shrubs that form a more complete cover than do plants
associated with creosote bush scrub. Soils are usually fine-textured, poorly drained with high
(ranging from 0.2-0.7%) salinity and/or alkalinity. Habitats are generally moist, with a sandy
loam soil. Dominant species are one or more Atriplex, including Big Saltbush (Atriplex
lentiformis), Allscale (Atriplex polycarpa) and Four-winged Saltbush (Atriplex canescens var.
linearis). In some areas, Alkali Goldenbush and Honey Mesquite are common representatives of
this habitat type. The latter are found east of Lake Cahuilla County Park in southern La Quinta.
In scattered fallow parcels throughout the eastern Sphere, diminished examples of this habitat
occur in various stages of re-growth. Where these “pseudo-Saltbush Scrub” areas occur, they
often include a mixture of non-native alkali-tolerant species as well as native Atriplex.
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Common Species
There are primarily two categories of habitat associated with wildlife common to the planning
area. The most prevalent consists of the very disturbed and fragmented patchwork of remnant
sand field, saltbush scrub, weedy (ruderal), agricultural, and residential/recreational
development. Common species in this environment are those that are capable of surviving in
ruderal plant communities or near residential, commercial, agricultural, and golf course
developments.
Another habitat category is comprised of native, less altered habitats where the Santa Rosas and
associated alluvial fans and canyons overlap in the western and southern portions of the Planning
area. These remaining areas of native habitat sustain both common as well as some sensitive
desert wildlife species and plant communities. Common wildlife species include insects such as
several species of harvester and crater-nest ants, the native creosote bush grasshopper, burrowing
sand roaches and sand scorpions, a wide range of native and non-native bee and wasp species,
black widow spider and others.
Common species with potential to occur in the Planning Area are further described below.
Common amphibians include the California toad, Pacific Tree Frog and the non-native,
naturalized Bullfrog where habitat provides suitable moisture. A variety of common lizard and
snake species are found in the Planning Area. Lizard species include the Great Basin Whiptail,
Side-blotched Lizard, Desert Iguana and Common Chuckwalla. Common snake species known
from the Planning Area include Red Coachwhip, California Kingsnake, and Sonoran Gopher
Snake, as well as venomous snake species including the Colorado Desert Sidewinder, which
occurs in sandy habitats, and the Southwestern Speckled Rattlesnake, which is generally found in
rocky habitats.
The Planning Area is also home to or is utilized by a wide variety of common bird species. Non-
resident bird species may migrate through the area or utilize it for breeding or nesting only.
Certain species nest elsewhere but over-winter in the Planning Area, while others species
permanently reside in La Quinta. Verdin, Abert’s Towhee, Black-Tailed Gnatcatcher, Gambel’s
Quail, Mourning Dove and Ladder-Backed Woodpecker use Desert Dry Wash Woodlands and
wash habitats containing mixed shrub and tree habitat that provides primary nesting habitat.
Other nesting sites include shrubs, ground surfaces and animal burrows within Creosote Bush,
Saltbush and Woody Scrub communities. Landscaping within residential and/or recreational
areas, as well as agricultural plantings, especially date palm groves, also provide suitable nesting
habitat. Species utilizing agricultural areas include Red-Tailed and Red-Shouldered Hawk, Great
Horned Owl, and American Kestrel. Raptors and common Ravens utilize cliff faces, rock
outcrops and hillsides located in mountainous areas which occur primarily within Sphere areas.
Black-Throated Sparrow, Horned Lark, Loggerhead Shrike and Say’s Phoebe characteristically
utilize creosote bush, saltbush, and ruderal scrub communities within the Planning Area. A
variety of songbird species use both desert riparian and scrub habitats in the winter months only;
these include the Yellow-Rumped Warbler, White-Crowned Sparrow, Blue-Gray Gnatcatcher
and Ruby-Crowned Kinglet.
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These and other common species are not designated species of concern, however, most of them
are protected by the provisions of the Migratory Bird Treaty Act (MBTA). The MBTA prohibits
disturbing nests, eggs, and incubating birds, and of hatchling and fledgling birds during active
nesting. The Burrowing Owl is a “covered” species under the MSHCP and is also protected by
the MBTA. Although the MSHCP currently only requires surveys for Burrowing Owl within
Conservation Areas, the MBTA requires surveys and mitigation anywhere Burrowing Owl is
observed in the Planning Area.
Numerous larger common mammal species are found in the Planning Area, such as the Black-
Tailed Jackrabbit Desert Cottontail, Striped Skunk, Northern Raccoon, Kit Fox, and Coyote.
Smaller mammals include Pocket Mice, Cactus Mouse, Kangaroo Rats, Desert Woodrat, White-
Tailed Antelope Squirrel, and California Ground Squirrel. Many of these non-special status
species utilize a variety of habitat types within the Planning Area.
Special Status Species
There are several plant and animal species known or thought to occur within the Planning Area
that are designated as Special Status species by federal, state and/or local agencies. Certain
species within the Coachella Valley region are discussed herein as special status species in that
they are locally endemic or utilize unique habitat.
Lists of these sensitive species are maintained by the U.S. Fish and Wildlife Service (USFWS)
and the California Department of Fish and Game (CDFG), which provide information about
species ranges and occurrence probabilities. The California Native Plant Society (CNPS) is a
non-profit conservation organization that maintains listings of native flora and determines the
status of each species as rare, threatened, and/or endangered.
The following definitions are used by these agencies to determine the status of qualified species:
(1) “Endangered” species are those with such limited numbers that they are considered to be in
imminent danger of extinction; (2) “Threatened” species are those likely to become endangered
within the foreseeable future, particularly on a local scale; and (3) “Sensitive” and “rare” species
are those that are naturally rare or have been locally depleted or put at risk by human activities,
and although perpetuation of these species does not appear to be significantly threatened, they
are considered vulnerable and may be candidates for future listing.
Sensitive species listed in the following tables are those that have the potential to occur within
the Planning Area and vicinity. The Biological Report, included as an appendix to this document,
provides a comprehensive listing of sensitive species associated with the City, Sphere of
Influence and vicinity. Following the tables is a description of each of the sensitive species.
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Table III-11
Special Status Plants in the La Quinta General Plan Area and Vicinity
Common
Name
Scientific
Name
Habitat
State and Local
Status
Federal
Status
Chaparral
Sand-Verbena
Abronia villosa
var. aurita
Sandy areas
Chaparral/Desert
dunes
CNPS List 1B.1
State: S2.1
None
Glandular Ditaxis
Ditaxis claryana Sandy habitats
Sonoran Desert
scrub
0-465 meters
CNPS List 2.2
State: S1S2
None
California Ditaxis
Ditaxis serrata
var. californica
Sonoran Desert
Scrub
CNPS List 3.2
State: S2.2
None
Table III-12
Special Status Reptiles in the La Quinta General Plan Area and Vicinity
Common
Name
Scientific
Name
Habitat
State and Local
Status
Federal
Status
Flat-tailed Horned
Lizard
Phyrnosoma
mcallii
Sandy habitats with
adjacent hardpan, often
sparsely vegetated, also
saltbush habitats
State: S2
CDFG: CSC
CVMSHCP
None
Coachella Valley
Fringe-toed Lizard
Uma
inornata
Sand dunes, sand fields CDFG:
Endangered/S1
CVMSHCP
Threatened
Table III-13
Special Status Bird Species in the La Quinta General Plan Area and Vicinity
Common
Name
Scientific
Name
Habitat
State and Local
Status
Federal
Status
Burrowing Owl Athene
cunicularia
Burrows/abandoned
Foundation structures,
Creosote Bush & Ruderal Scrub
(edges of canals/agriculture)
State: S2
CDFG: CSC
CVMSHCP
None
Prairie Falcon
Falco
mexicanus
Cliff faces (nesting),
Open habitats for foraging
State: S3
CDFG: Watchlist
None
Black-tailed Gnatcatch Polioptila
melanura
Desert scrub and
desert wash woodland habitats
State: S4 None
Loggerhead Shrike Lanius
ludovicianus
Fairly common in a
variety of open
habitats
State: S4
CDFG: CSC
None
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Table III-14
Special Status Mammal in the La Quinta General Plan Area and Vicinity
Common
Name
Scientific
Name
Habitat
State and
Local Status
Federal
Status
Western Yellow
Bat
Lasiurus
xanthinus/ega
Primarily roosts in
the dead fronds of
palms, including
landscape specimens
State: S3
CDFG: CSC
CVMSHCP
None
Pocketed
Free-tailed Bat
Nyctinomops
femorosaccus
Variety of arid habitats
Desert Scrub, Palm
Oasis, Desert Wash,
roosts in rocky cliffs
State: S2S3
CDFG: CSC
None
Palm Springs
Round-tailed
Ground Squirrel
Xerospermophilus
tereticaudus
chlorus
Desert Scrub, Desert
Wash, Alkali Scrub,
& levees, golf course
edges w/ adjacent
native habitat
State: S1S2
CDFG: CSC
CVMSHCP
Candidate
Peninsular
Bighorn Sheep
Ovis canadensis
nelsoni DPS
Lower elevations of the
eastern Peninsular
Ranges, including
canyon
bottoms, alluvial fans,
and mountain slopes
Threatened
CVMSHCP
Endangered
Table Legend
Habitat: terrestrial natural community descriptions per Holland (1986)
State of California and Local Status: Endangered, Threatened, Protected, Special Concern status per the California Fish and
Game Code of 2007, as well as all species protected by the Coachella Valley Multiple Species Habitat Conservation Plan (species
covered by plan listed as CVMSHCP).
Federal Status: Endangered, Threatened and Candidate for listing status per the Endangered Species Act of 1973 (as amended).
It is mandatory that federally listed plant species be fully considered during preparation of environmental documents pertain ing
to the California Environmental Quality Act or National Environmental Policy Act, or any federal authorization.
California Native Plant Society (CNPS) listing rankings (CNPS 2010) are described as follows:
List 1A: Plants (29) presumed extinct in California because they have not been seen or collected in the wild in
California for many years.
List 1B: Plants considered rare and endangered in California and throughout their range. All of the plants
constituting List 1B meet the definitions of Section 1901, Chapter 10 (Native Plant Protection Act) or
Sections 2062 and 2067 (California Endangered Species Act) of the California Department of Fish and
Game Code and are eligible for state listing. It is mandatory that these plant species be fully
considered during preparation of environmental documents pertaining to the California Environmental
Quality Act.
List 2: Plants considered rare, threatened or endangered in California but which are more common elsewhere.
List 3: Plants about which more information is needed to assign them to one of the other lists.
List 4: Plants of limited distribution (a “watch list”) or infrequent throughout a broader area in California, their
vulnerability to threat appears low at this time.
Threat Rank
0.1 Seriously threatened in California (high degree/immediacy of threat)
0.2 Fairly threatened in California (moderate degree/immediacy of threat)
0.3 Not very threatened in California (low degree/immediacy of threat)
State Ranks
S1: 5 or fewer viable occurrences or fewer than 1,000 individuals statewide and/or less than 2,000 acres
S2: 6 – 20 viable occurrences or fewer than 3,000 individuals statewide and/or 2,000 – 10,000 acres
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S3: 21 – 100 viable occurrences or fewer than 10,000 individuals statewide and/or 10,000 – 50,000 acres
S4: Greater than 100 viable occurrences statewide and/or greater than 50,000 acres, apparently secure statewide
S5: Community demonstrably secure statewide
Where two ranks are given (eg. S1S2) the species’ rank falls between the two ranks
Threat Ranks
0.1: Very threatened
0.2: Threatened
0.3: No current threats known
Of the species shown in the preceding tables, seven are not covered by the MSHCP. The
following briefly describes these sensitive species and the likelihood of their occurrence in the
Planning Area. Exhibit III-2, CNDDB, Critical and Modeled Habitat shows the general location
of each species.
Sensitive Plant Species
Chaparral Sand-Verbena (Abronia villosa var. aurita) has been reported within the Planning
Area at one location, which is now developed. Therefore, no further discussion of this species is
included herein.
Glandular Ditaxis (Ditaxis claryana) is a small perennial herb of the Spurge family. It has been
recorded at two locations in the Planning Area, within Sonoran Creosote Bush Scrub habitat.
Both of these locations have been developed. The potential for this species to occur in the
Planning Area is low, limited to southern and western portions of the area where suitable habitat
is located. Mitigation for impacts to this species is primarily through spring or fall surveys after
sufficient rainfall, and avoidance where populations are identified.
California Ditaxis (Ditaxis serrata var. californica) is another small perennial herb of the Spurge
family. It is typically found in rocky alluvial fans, flood plains and dry washes, and in the
Planning Area has been recorded in one location, west of Avenida Montezuma and Calle
Nogales, in the Cove. This location still offers viable habitat for this species. Potential
occurrence is moderate to high in the southern and western areas of the City.
Sensitive Bird Species
Burrowing Owl
(Athene cunicularia)
uses man-made structures such as piles of tree branches or
debris, buildings or pipes, or burrows dug out by other wildlife, such as kit fox, desert tortoise or
ground squirrels. Burrowing owl is a species of special concern and a protected raptor.
Therefore, notification of CDFG and approved mitigation are required prior to any activity that
may impact the species. Potential occurrence locations in the Planning Area include wherever
undeveloped or fallow land occurs. It has been observed during surveys conducted in 2003 in the
southern portion of the Planning Area. Mitigation includes site-specific surveys to identify the
species.
Prairie Falcon (Falco mexicanus), a medium to large migratory raptor that winters in the region,
prefers cliffs or steep rock ledges in the western and southern parts of the Planning Area. This
species has been observed at the southwestern end of the City. It is a protected raptor as well as a
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species of special concern. Therefore, CDFG notification and approved mitigation prior to any
activity that might impact the species are required. Site-specific surveys are needed to identify
the species.
Black-tailed Gnatcatcher (Polioptila melanura) has a range that extends through the Sonoran and
Chihuahuan Deserts of the US and northern Mexico. It lives in pairs throughout the year. The
species is a small, resident songbird and has been identified at two locations in the Planning
Area. It is most likely to occur in the western and southern portions of the City and Sphere. Site-
specific surveys are needed to identify the species. Conservation of this species is served by
limiting impacts to Desert Dry Wash Woodland and Sonoran Creosote Bush Scrub habitats.
The Loggerhead Shrike (Lanius ludovicianus) is a reasonably common species in California,
although in other parts of the U.S. it has been significantly depleted. In the Planning Area is
occurs in undeveloped areas, hillsides to the south and west, and on the periphery of agricultural
fields. There are no specific study or preservation prescriptions associated with this species.
Sensitive Mammal Species
Pocketed Free-tailed Bat (Nyctinomops femorosaccus) is so named after the small fold, or
“pocket” in its wing membrane. The species has large ears and long wings; these bats fly
quickly and hunt insects on the wing. They roost in colonies of less than 100 in caves, crevices in
rocky cliffs, or buildings. In the Planning Area they have been observed in one location, which
has been developed as a golf course but still has suitable foraging and drinking use for this
species. There is also suitable roosting habitat still located east of the site. The greatest threats to
this species are habitat loss and unmanaged use of pesticides. Conservation prescriptions to
protect this species include limiting impacts to rocky habitats that the species utilizes for
roosting.
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Habitat Protection
Coachella Valley Multiple Species Habitat Conservation Plan
The Coachella Valley Multiple Species Habitat Conservation Plan (MSHCP) is a joint regional
planning effort of the US Fish and Wildlife Service (USFWS), the California Department of Fish
and Game (CDFG), the Bureau of Land Management (BLM), the U.S. Forest Service (USFS),
and the National Park Service (NPS), as well as Riverside County and most local jurisdictions
within the Coachella Valley, including the City of La Quinta. The MSHCP is intended to
streamline and simplify compliance with the State and Federal Endangered Species Acts (CESA
and FESA, respectively) and other applicable laws and regulations; obtain Take Authorization
(Take Permits) pursuant to the FESA and the California Natural Community Conservation
Planning (NCCP) Act for Covered Activities in the Coachella Valley; and balance environmental
protection with regional economic objectives. The City is a permittee under the MSHCP.
The General Plan Area is within the planning area for the Coachella Valley Multiple Species
Habitat Conservation Plan (MSHCP). A portion of the Santa Rosa and San Jacinto Mountains
Conservation Area lies within the General Plan Area, on lands west of the eastern edge of the
Santa Rosa Mountains. The location of this Conservation Area is shown on Exhibit III-3, Land
Ownership and Conservation Areas. Should future development be proposed within the
Conservation Area, it will be subject to compliance with specific goals and measures set forth in
the MSCHP. These include conservation of lands for Essential Habitat for Peninsular Bighorn
Sheep, as well as conservation of lands for other MSHCP-protected species and habitat, such as
Le Conte’s thrasher, Desert tortoise, desert dry wash woodland natural community, and
conservation of occupied burrowing owl burrows.
Conservation goals for La Quinta are set forth in the MSCHP. They are:
2,545 acres of Essential Habitat for the Peninsular Bighorn Sheep
387 acres of Conserved Habitat for the Le Conte’s thrasher
1,409 acres of Conserved Habitat for Desert Tortoise
76 acres of desert dry wash woodland
Conserve occupied Burrowing Owl burrows as provided for in the MSHCP avoidance,
minimization and mitigation measures.
On lands not designated for conservation, future development will be required to pay a
mitigation fee to ensure the future availability of funds to purchase conservation lands. These
fees are intended to offset the potential impacts of that development on the natural environment.
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Regulation of Streambeds and Watercourses
There are numerous washes and streambeds in the Planning Area. In addition to the Whitewater
River, there are several smaller, mostly unnamed streams that drain from the Santa Rosa
Mountains. Streambeds and washes are subject to regulation by a variety of state and federal
regulatory agencies. Where streambeds and washes qualify as Waters of the State of California,
they fall under the jurisdiction of the California Department of Fish and Game (CDFG). Water
bodies determined to be Waters of the U.S. also fall under the jurisdiction of the U.S. Army
Corps of Engineers (USACOE). Development projects that require construction activities within
these water bodies must secure applicable permits.
Projects within streams and washes under CDFG jurisdiction may require a Streambed Alteration
Agreement. Where USACOE holds jurisdiction, a Section 404 permit may be required to satisfy
requirements of the federal Clean Water Act. USACOE may also require a formal delineation of
the affected waterbody to determine the extent of jurisdictional Waters of the U.S. Compliance
with Section 401 of the Clean Water Act may also be required, necessitating a Water Quality
Certification through the State Regional Water Quality Control Board (RWQCB) for state
certification, and in some cases, the U.S. Environmental Protection Agency (USEPA) for federal
certification.
The Whitewater River, which is the primary ephemeral stream in the Coachella Valley, runs
generally northwest to southeast through the Coachella Valley. East of Washington Street, the
river is called the Coachella Valley Stormwater Channel. The Channel qualifies as both a Water
of the State of California, and a Water of the U.S. Therefore, construction activities within the
Channel require consultation with both CDFG and the USACOE, and permits must be secured
from both agencies. In general, when a 404 permit is required, a state 401 Water Quality
Certification is also required.
In the Planning Area, smaller streams emanating from the Santa Rosa Mountains include Bear
Creek, which enters the City at the south end of the Cove, and the La Quinta Evacuation
Channel, which extends northeasterly from the Bear Creek Channel. Such drainages constitute
waters of the State and are under the jurisdiction of the CDFG. They are not considered “waters
of the United States,” as defined by the USACOE. Project developers proposing construction
activities within these streams must consult with CDFG, and may be required to obtain a
Streambed Alteration Agreement as well as any other applicable permits and approves prior to
the initiation of work.
Migratory Bird Treaty Act
As previously discussed, nearly all common and special status birds in the Planning Area are
protected under the federal Migratory Bird Treaty Act (MBTA). Under the MBTA, disturbance
of nests, eggs or incubating birds while nests are active is prohibited. Within the Planning Area,
the nesting period generally extends from March through August. Pre-construction surveys are
required prior to project activities to determine if active nests are present within trees and bushes.
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2. Project Impacts
Potential Direct and Indirect Impacts
Implementation of the proposed General Plan will facilitate new development and growth that
will result in impacts to biological resources in the Planning Area. Population growth is expected
to result in increased disturbance on open space lands, including human use, vehicle travel,
garbage dumping, and potential increased frequency of wildfires. These activities have potential
to impact plant communities that are as yet undisturbed by human activity.
Over time, certain non-native, invasive plants, such as Sahara Mustard, may be expected to
spread in existing sand field habitat. While much of this habitat has already been developed, the
continued spread of this and other non-native, invasive species has potential to result in adverse
impacts to native species and supporting habitats.
Continued urban growth and development may be expected to result in displacement, injury or
even death to wildlife species occurring on currently undeveloped or sparsely developed lands.
Where native habitat is still present in the planning area, it may be impacted by increased vehicle
travel, alteration of soils, vegetation removal and habitat degradation associated with new
development. This is particularly true in the eastern Sphere as well as the southern and western
portions of the planning area. Individual development projects may disrupt courtship and
breeding behaviors of some native wildlife.
Future development in the planning area may also result in incidental take of listed species,
whether they are residents or seasonal migrants. Impacts to special status species are cumulative,
given other development that has or may be expected to take place in the Coachella Valley. It
should be noted that these impacts are addressed in the Coachella Valley Multiple-Species
Habitat Conservation Plan (MSHCP), which provides mitigation for incidental take resulting
from individual development projects. Mitigation includes payment of per-acre mitigation fees
for all new development within the MSHCP planning area.
Potential Impacts to Plant Communities
As development occurs within the General Plan Area, there is potential for the destruction of
entire populations of common and sensitive plant species. There are no federal Threatened or
Endangered plant species thought to occur in the Planning Area, however there are two special
status plant species with probability of occurring. It is expected that impacts to special status or
comment plant species will be less than significant if they are present, since they are most likely
to occur within the southern and western portions of the Planning Area. These areas are
designated for Open Space use within the existing and proposed General Plan and are not
planned for development. Introduction of non-native plant species associated with landscaping
could result in native plant species competing for water, nutrients and space.
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Potential Impacts to Invertebrates, Reptiles and Amphibians
Invertebrates, reptiles and amphibians that occur in the Planning Area will be impacted by
increased urbanization. These species are especially vulnerable to the impacts of off-highway
vehicle traffic, as well as crushing from grading and construction activities. The Coachella
Valley Fringe-Toed Lizard is the only federal listed Threatened and state listed Endangered
reptile species that is thought to occur in the Planning Area. As urban development has
encroached, the sandy habitat that supports this species has become increasingly compromised
through the construction of roads, buildings and fences and other barriers that disrupt the natural
blowsand process. Future development has potential to result in permanent loss of habitat that
will impact individuals as well as entire populations. The Coachella Valley Fringe-Toed Lizard
is a covered species under the MSHCP, which addresses impacts to this species through payment
of fees and other measures.
Potential Impacts to Birds
As development in the Planning Area continues, it may be expected to result in habitat
degradation and the direct loss of foraging and nesting sites for a variety of common and special-
status bird species. Predation by domestic pets, increased competition for limited nesting sites,
pesticide ingestion, and the introduction of parasites constitute indirect impacts that may occur.
Some species may be especially disrupted by off-road vehicle activity, particularly during
breeding season. Bird species that can tolerate human disturbance will likely continue to inhabit
developed areas, and may be attracted to newly landscaped areas. Burrowing Owl may be
impacted by the conversion of agricultural lands to urban development. This species is covered
by special survey requirements of the MSHCP and receives protection under California Fish and
Game code.
Potential Impacts to Mammals
Development activities involve mass grading and clearing, resulting in the removal of vegetation
and wildlife. A wide range of common and sensitive wildlife species occur in the Planning Area
and may be subject to increasing adverse impacts as urbanization encroaches. Bats may roost in
abandoned buildings, bridges over the Whitewater River, and untrimmed date palm trees, and
these should be surveyed prior to disturbance. The Pocketed Free-tailed Bat typically roosts in
rocky terrain of the Santa Rosa Mountains. The existing and proposed General Plan designated
these lands as Open Space, preserving them from development, and this is expected to avoid or
minimizing potential impacts to this species.
The direct and indirect impacts of continued development affect smaller mammals, including a
variety of common and sensitive species. Off-road vehicles, domestic pet predation, and surface
disturbance that could crush burrows pose specific hazards to these species, such as the Palm
Springs Round-Tailed Ground Squirrel, which is a candidate for Federal listing.
Peninsular Bighorn Sheep (PBS) habitat occurs on the rocky hillsides of the Santa Rosa
Mountains, including lands that occur in the southwestern portion of the Planning Area. Portions
of these lands fall within the MSHCP Santa Rosa and San Jacinto Mountains Conservation Area.
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It is expected that development within these areas will continue to be limited, both by the City’s
Hillside Conservation Zone Ordinance and restrictions on development within the MSHCP
Conservation Area. However, this species may be subject to indirect impacts associated with
development at the base of the mountain slopes. PBS are susceptible to toxic plants associated
with landscaping, collision with vehicles, and parasites. This species is generally intolerant to
human disturbance. They have been known to abandon hillside habitat as a result of human
activities such as hiking or other recreational activities. PBS are a covered species within the
MSCHP and development within or adjacent to PBS habitat is subject to a variety of
requirements set forth in the MSCHP.
Summary of Impacts
The ultimate build out of the General Plan Planning Area has the potential to significantly impact
biological resources by reducing native habitat areas and directly affecting fauna. However, the
majority of lands on which development will occur are on the Valley floor, in areas already
impacted by urban development or agricultural activities. These areas are part of the MSHCP,
and new development projects will be required to pay mitigation fees associated with the
MSHCP to allow for the preservation of habitat and species in designated conservation areas.
Further, areas where non-covered sensitive species occur are identified in the General Plan, and
the Plan requires the preparation of special studies for projects proposed in those areas. Those
studies will provide an assessment of the potential impacts, and recommend mitigation measures
if necessary.
The General Plan also designates Natural Open Space for hillside areas on the west and
southwest portions of the City, which are areas of potential habitat for the endangered Peninsular
Bighorn Sheep. The Natural Open Space designation will not result in development in these
areas, and will protect these lands for the long term.
Finally, existing regulations, including the provisions of the MSHCP, the requirements enforced
by the California Department of Fish and Game, the US Fish and Wildlife Service and the US
Army Corps of Engineers will continue to be enforced by the City. These requirements and
regulations are designed to protect species, water bodies and habitats from negative impacts
associated with development. The General Plan acknowledges these requirements, and includes
policies to maintain their implementation for future projects as they are proposed.
The imposition of the mitigation measures identified below will assure that impacts to biological
resources will be reduced to less than significant levels.
3. Mitigation
The build out of the General Plan will result in impacts to biological resources. With the
implementation of the following mitigation measures, however, these impacts will be reduced to
less than significant levels.
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1. The City shall require payment of Coachella Valley Multiple Species Habitat Conservation
Plan mitigation fees prior to issuance of occupancy permits for development projects
required to pay such fees.
2. The City shall refer land owners and developers of lands slated for conservation under the
MSHCP to the Coachella Valley Association of Governments and/or Coachella Valley
Conservation Commission for guidance and permitting assistance.
3. The City shall maintain and update as necessary all maps of conservation and mitigation fee
boundaries for the MSHCP.
4. Where appropriate, the City shall require site-specific, species-specific surveys for the seven
species not covered by the MSHCP.
5. Projects proposed for development within areas identified as having potential for occurrence
of Glandular Ditaxis, California Ditaxis, Prairie Falcon, Black-tailed Gnatcatcher,
Loggerhead Shrike and Pocketed Free-tailed Bat, as identified in the General Plan, shall be
required to retain a qualified biologist to prepare biological resource surveys.
6. Prior to the issuance of any ground disturbing permit for qualifying projects19 in a
Conservation Area, the City shall require a protocol compliant survey for Burrowing Owl, in
compliance with the MSHCP Section 4.4.
7. The City shall require protocol compliant surveys for burrowing owl prior to the issuance of
any ground disturbing permit for fallow lands outside MSHCP Conservation areas
8. The City’s Land Use Map shall designate as “Open Space” all publicly owned Conservation
lands for the MSHCP.
9. In compliance with the requirements of the Migratory Bird Treaty Act (MBTA), the City
shall continue to require that for development projects proposing removal of vegetation
between March and August, a qualified biologist shall be retained to determine whether any
bird nests or young occur on the site, and if they occur, to provide mitigation measures
compliant with the MBTA.
10. In compliance with the regulatory requirements of the California Department of Fish and
Game, the U.S. Army Corps of Engineers and the Regional Water Quality Control Board as
they relate to “waters of the State of California” and/or “waters of the United States”, and
prior to the initiation of any project within the Coachella Valley Stormwater Channel, the
City shall require that consultation and/or permitting by State and federal agencies by
demonstrated in writing.
19 Qualifying projects do not include single family residences, non-commercial accessory uses and structures
(including but not limited to second units on an existing legal lot), or the operation and maintenance of Covered
Activities other than levees, berms, dikes, and similar features known to contain burrowing owl burrows.
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11. Prior to the initiation of any project within any defined blueline stream other than the
Coachella Valley Stormwater Channel, the City shall require that consultation and/or
permitting by California Department of Fish and Game be demonstrated in writing.
12. The City shall encourage new development projects to incorporate native desert plant
materials into project landscaping to the greatest extent possible, and shall discourage the use
of invasive, non-native species.
13. The City shall use zoning standards and the design review process to assure that adequate
buffers are provided between urban development and environmentally sensitive areas,
including Conservation Areas for the MSHCP, to the greatest extent possible.
Mitigation Monitoring and Reporting
A. The City shall review the potential impacts of development projects on biological resources
through the Initial Study review process. Where appropriate, impacts shall be clearly
documented and mitigation measures recommended.
Responsible Parties: Planning Department, Project Developer/Consulting Biologist.
B. Prior to the issuance of occupancy permits, the City shall require that all applicable
biological resource mitigation actions, including payment of Coachella Valley Multiple
Species Habitat Conservation Plan mitigation fees by applicable projects, and compliance
with applicable state and federal regulatory permits, shall be satisfied.
Responsible Parties: Planning Department, Biologist, California Department of Fish and
Game, California Regional Water Quality Control Board, U.S. Army Corps of Engineers,
Project Developer/Consulting Biologist.
C. On an annual basis, City staff shall evaluate biological resources reference materials and
update City records and inventories to ensure that resource databases are maintained in a
timely and adequate manner.
Responsible Parties: Planning Department, Project Developer/Consulting Biologist.
D. During grading, construction and other development activities, development projects shall be
monitored to ensure that grading limits are observed and that native and other appropriate
landscape materials are preserved and integrated into all areas of the project in accordance
with approved landscape plans.
Responsible Parties: Planning Department, Developer/Consulting Biologist.
Cultural Resources E.
Introduction and Background
This section discusses the rich cultural resources in La Quinta, and assesses impacts on these
resources from future growth and development brought on by the General Plan Update. It also
provides mitigation measures to reduce cultural resource impacts. The following discussion is
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based on the Cultural Resources Technical Report and the Paleontological Technical Report
prepared by CRM Tech in 2010.
Thresholds of Significance/Criteria for Determining Significance
Article 5, Section 15064 of the CEQA Guidelines provides guidance for determining the
significance of the environmental effects caused by a project. Appendix G of CEQA provides a
list of environmental factors that potentially may be affected by completion of a project. The La
Quinta 2035 General Plan Update would have a significant effect on Cultural Resources if it is
determined the project will:
a) Cause a substantial adverse change in the significance of a historical resource as
defined in 15064.5.
b) Cause a substantial adverse change in the significance of an archaeological resource
pursuant to 15064.5.
c) Directly or indirectly destroy a unique paleontological resource or site or unique
geologic feature.
d) Disturb any human remains, including those interred outside of formal cemeteries.
The CEQA Guidelines define the term “historical resource” to include the following20:
1. A resource eligible by the State Historical Resources Commission as listed in the
California Register of Historical Resources (Public Resource Code 5024.1, Title 14 CCR,
Section 4850 et seq.)
2. A resource included in a local register of historical resources as defined in section
5020.1(k). This includes properties recognized as historically significant by a local
government pursuant to a local ordinance or resolution.
3. Any object, building, structure, site, area, place, record, or manuscript which a lead
agency determines to be historically significant or significant in the architectural,
engineering, scientific, economic, agricultural, educational, social, political, military, or
cultural annals of California. Generally a lead agency can determine a resource to be
‘historically significant’ if it meets criteria for listing on the California Register of
Historic Resources (Pub. Res. Code 5024.1, Title 14 CCR, Section 4852). The following
includes the criteria for listing:
a. Is associated with events that have made a significant contribution to the broad
patterns of California’s history and cultural heritage.
b. Is associated with the lives of person important in our past.
20 “California Environmental Quality Act 2010, Statutes & Guidelines”, prepared by AEP, January 1, 2010.
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c. Embodies the distinctive characteristics of a type, period, region, or method of
construction, or represents the work of an important creative individual, or possesses
high artistic values
d. Has yielded, or may be likely to yield, information important in prehistory or
history.
4. A lead agency is not precluded from determining a resource to be a ‘historical
resource’ as defined by Public Resources Code 5020.1(j) or 5024.1 when the resource is
not listed in the California Register of Historical Resources, included in a local register of
historical resources, or identified in an historical survey.
SB 18 and Native American Consultation
The purpose of SB 18 is to protect traditional tribal cultural places. In accordance with the Bill,
the City of La Quinta is required to offer consultation with California Native American Tribes
regarding proposed land use planning decisions involving General Plan adoption or amendment.
In preparation of the Cultural Resources Technical Report for the La Quinta General Plan
Update, contact has been made with regionally active Tribes provided by the Native American
Heritage Commission. CRM Tech received only one letter of response, including a letter from
the Cabazon Band of Indians, during preparation of the Cultural Resources Technical Report.21
1. Existing Conditions
Cultural Resources are important for understanding the history and heritage of the community,
and for preserving important archaeological and paleontological resources. The City of La
Quinta and the Coachella Valley region have a rich cultural past, as discovered through recent
paleontological and archaeological surveys.
Approximately 5 million years ago, the Coachella Valley was part of an inland sea, as the Gulf
of California extended up to the present day Banning Pass. Paleontological resources continue to
be found proving aquatic life was once part of the region’s past.
It is believed that the earliest human settlements occurred 8,000 to 12,000 years ago from Native
Americans. Prehistoric records show that early Native American peoples in the Coachella Valley
were from the Takic speaking Cahuilla tribe.
The first noted Spanish explorers in the Coachella Valley were Jose Romero, Jose Maria
Estudillo, and Romualdo Pacheco, who in 1823 led expeditions to find a route to current day
Yuma, Arizona. These explorers traveled through the Coachella Valley through what was known
as the Cocomaricopa Trail, which was an ancient Indian trading route.
21 “Cultural Resources Technical Report for City of La Quinta General Plan (2010 Update), prepared by CRM
Tech, July 8, 2010.
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Non-native settlements began to flourish across the Coachella Valley as new federal laws,
including the Homestead Act and Desert Land Act, opened lands for new settlers by the late
1870’s. The discovery of underground water sources began to increase farming activities
throughout the Valley in the early 20th century. By 1910, the date palm industry began to flourish
in the region.
Tourism reached La Quinta and the Coachella Valley in the 1920’s, as the rich and famous of
Hollywood began coming to the Valley to enjoy the beautiful scenery and climate. The entire
Coachella Valley began to boom after World War II as more residents and visitors came to the
area.22
Paleontological Resources
Paleontological Resources are fossilized records of previous life forms found beneath the ground
or among exposed geologic features. Fossils are nonrenewable remains of organisms that include
vertebrate, invertebrate, plant, or marine organisms typically of more than 10,000 years of age.
They are a significant record of ancient life, important for understanding evolutionary changes in
organisms, providing information on past climatic conditions and ecology, and helping scientists
determine ages of rocks and sediment in which they are found. Fossils are mostly found within
sedimentary rock, and commonly include marine shells, bones and teeth of fish, reptiles, and
mammals, leaf assemblages, and petrified wood. The location and type of soil that fossils are
found in are an important part of paleontological resources, as they indicate typical geologic
formations that are conducive to finding fossils.
Paleontological sensitivity refers to the degree to which a geologic formation is likely to produce
significant nonrenewable fossils, based on past discoveries within a particular geologic
formation. Sedimentary units tend to have high sensitivity due to their potential for significant
paleontological resources.
Significant paleontological resources include vertebrate or invertebrate fossils. In general,
vertebrate fossils, or those with backbones, including mammals, birds, reptiles, amphibians, and
fish, tend to be more rare than invertebrate fossils, and therefore are considered a more
significant paleontological resource. The geologic formations that vertebrate are found in are
considered areas of highest sensitivity. All identifiable fossils, however, are considered
potentially significant until determined to be insignificant by a qualified paleontologist.
The geologic formations and units in the General Plan Update Planning Area have been studied
to determine paleontological significance. The Planning Area is made up of five geologic
formations, including Dune Sand, Granitic Rock, Pleistocene Alluvium, Holocene Alluvium, and
Lake Cahuilla Beds. Exhibit III-4 shows the location of these geologic formations. Through
literature and map research, institutional records research, and past paleontological monitoring
from recent construction activities, these different geologic formations have been designated as
“high,” “low,” or “undetermined” according to their paleontological sensitivity. Pleistocene
22 “Cultural Resources Technical Report for City of La Quinta General Plan (2010 Update), prepared by CRM
Tech, July 8, 2010.
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Alluvium is considered to have the oldest sediments, and therefore likely to contain the greatest
source of fossil resources. The Lake Cahuilla beds are also designated as a high sensitivity area
due to an abundance of fossils. Granitic Rock sediments are considered low sensitivity due to
lack of fossil resources, and areas of Dune Sand and Holocene Alluvium are undetermined, due
to limited study or limited exposure of sediment likely to contain fossil resources. The locations
of each of these three paleontological sensitivity areas are also identified in Exhibit III-4.
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High Sensitivity Paleontological Areas
Areas that are determined to be of “high” paleontological sensitivity include areas made up of
Pleistocene sediments, and sediments from ancient Lake Cahuilla beds. Pleistocene sediments
are located in the southwestern portion of the Planning Area. Construction projects throughout
other areas of Riverside County have yielded significant fossil resources in Pleistocene sediment,
including highly significant vertebrate fossils. Recent studies and inventories conducted in the
General Plan Update Planning Area, however, have indicated that no significant paleontological
resources exist within local Pleistocene sediments. The closest paleontological resource found in
Pleistocene sediment was recorded three miles northeast of the northern portion of the Planning
Area, along the southern portion of the Indio Hills.23 Nevertheless, these areas are of high
sensitivity due to their potential for containing significant paleontological resources.
Sediments found within the Lake Cahuilla beds are associated with deposits from the ancient
Lake Cahuilla. These sediments cover a large portion of the eastern and southern portion of the
Planning Area. Although no Pleistocene age fossils have be reported in ancient Lake Cahuilla,
this area has yielded numerous vertebrate and invertebrate fossils that are less than 10,000 years
old. According to paleontological records, six paleontological localities have been recorded in
the southern section of the Planning Area, and include fish, lizards, snakes, rabbits, diatoms,
ostrapods, and mollusks. As a result of these finds, the Lake Cahuilla beds are of high
paleontological sensitivity, and potentially contain paleontological resources that could be
affected by earth-moving activities.24
Low Sensitivity Paleontological Areas
Areas determined as being of “low” paleontological sensitivity are areas made up of Granitic
Rock. These areas are located in the southwestern, southern and northwestern portion of the
Planning Area. Paleontological studies have shown these areas as not containing significant
paleontological resources and unlikely to contain fossil resources.
Undetermined Areas
Areas in the Planning Area made up of Holocene Alluvium and Dune Sand are considered the
youngest geologic formations, and therefore unlikely to contain significant fossil resources.
Holocene Alluvium is present in the western and southwestern portion of the Planning Area, and
Dune Sand is located in the northern portions of the Planning Area. Paleontological studies have
indicated that these young sediments may overlie older alluvium that contains Pleistocene age
fossils, and therefore may also be considered high sensitivity areas. Because of the complex
nature of these geologic formations, and lack of paleontological discoveries, these areas have
been designated as “Undetermined Areas” for paleontological resources.
Cultural Resources Discovered in Planning Area
The Planning Area is rich with history, as indicated by the large number of archaeological sites,
historic period buildings, and other historic and prehistoric discoveries found throughout it.
23 Paleontologic Resources Technical Report for City of La Quinta General Plan (2010 Update), prepared by CRM
Tech, August 12, 2010. 24 Ibid.
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These cultural resources include remnants from the Native Cahuilla people to more recent
residents of La Quinta. Cultural resources encompass all human related remnants as well as non-
traditional property types, such as citrus groves, date gardens, and natural features.
This section discusses the existing cultural resources that have been identified in the General
Plan Update Planning Area. Exhibit III-5 provides a map showing previously surveyed areas for
cultural resources within the Planning Area.25
Archaeological Resources
The archaeological resources found within the General Plan Update Planning Area are remnants
from prehistoric peoples who took advantages of the resources in ancient Lake Cahuilla. Lake
Cahuilla covered portions of La Quinta, primarily below the 42-foot above sea level contour.
Archaeological records show that ancient people followed the shoreline according to the various
lake levels, until A.D. 1650 when the lake rapidly receded to complete desiccation within 80 to
100 years. The Cahuilla people were believed to be the first inhabitants of the area dating back to
the Archaic Period, and thrived in the area until European settlers arrived in the early 1800’s.
Cultural surveys have identified approximately 500 archaeological sites, both historic and
prehistoric, in the Planning Area. In addition to these sites, approximately 170 isolates, or
localities with fewer than three artifacts, have also been discovered. The majority of these
archaeological finds are from Native American tribes and include pottery, burned animal bone,
grinding stones, chipped stone, cremation and other remains. Recent surveys in the sand dune
portions of La Quinta have found remnants from the Archaic Period, including the presence of
worked fine-grained, dark gray basalt and shell beads, and burial sites. Other Archaic sites have
been discovered throughout the Planning Area due to the presence of hunting remains, Olivella
beads, and basalt, which were common in the Archaic period. The oldest site recorded in the
Coachella Valley is located just outside the La Quinta city boundary, and includes a site proven
to be 2,700 years old. An archaeological survey prepared in the southwestern portion of the
Planning Area revealed more than 30 prehistoric archaeological sites, indicating that Village
sites were at one time concentrated along the shores of ancient Lake Cahuilla.
Recent contacts with local Native American tribes, including the Torres Martinez, Augustine,
and Cabazon bands of the Desert Cahuilla people have also uncovered culturally sensitive lands
within the Planning Area. Past development and earth-moving projects throughout the region
have uncovered Native American cremation and burial sites. Letters received from the Native
American Heritage Commission have also indicated that sacred Native American cultural
resources are located within a half-mile of the Planning Area.26
25 “Cultural Resources Technical Report for City of La Quinta General Plan (2010 Update), prepared by CRM
Tech, July 8, 2010. 26 “Cultural Resources Technical Report for City of La Quinta General Plan (2010 Update), prepared by CRM Tech,
July 8,2010.
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Historic Resources
Historic resources include culturally important buildings, structures, or features that are typically
related to non-Native settlements. The State of California has determined that historic buildings
are those older than 45-50 years of age. Over the last few decades, historic resources surveys
have revealed a large inventory of historic buildings, structures, and features in La Quinta.
The Riverside County Historical Commission prepared a historical survey between 1981 and
1983 and recorded 30 buildings and portions of the Coachella Canal within the La Quinta
Planning Area as historical resources. Between 1996 and 1997, the City of La Quinta recorded
60 additional properties and buildings as historical resources. As a result of that survey, the City
designated the Cove area as a potential historic district under the Historic Preservation
Ordinance, due to the large number of recorded historical buildings. In 2006, the City updated
the 1996-1997 survey and recorded an additional 183 buildings to the California Historical
Resources Inventory, and noted an additional 74 buildings as potentially significant historic
resources.
The combination of these past surveys have highlighted approximately 280 buildings and other
built features in the General Plan Update Planning Area as having the potential to be historically
significant and eligible for listing in the California Historic Resources Inventory. The majority of
these buildings are single-family homes of various ages, including both pre and post-WWII
vintage, and are representative of various architecture styles.27 The General Plan requires that
cultural resources, including potentially historic structures, be studied prior to their being
impacted by development.
27 “Cultural Resources Technical Report for City of La Quinta General Plan (2010 Update), prepared by CRM Tech,
July 8,2010.
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2. Project Impacts
Impacts to Historical Resources
Implementation of the General Plan Update will facilitate new development throughout the
Planning Area. Within the City limits, the majority of new development will be associated with
redevelopment or infill. As discussed above, there have been approximately 280 buildings and
other built features identified as having the potential to be historically significant within the
Planning Area. As such, future development projects, including modifications to existing
buildings, demolition, grading activities, site excavation, and construction could potentially
result in direct or indirect disturbance or destruction of historic resources. Since these structures
and features are documented, site surveys should be conducted to assess potential harm to these
resources, if alteration or demolition is proposed. The General Plan requires that site specific
studies be conducted when development is proposed. These studies will include an assessment of
the potential impacts to cultural resources, and assure that impacts to these resources are reduced
to less than significant levels.
The Sphere is more rural and does not contain the intensity of development found within the City
limits. Historical resources throughout the Sphere may be associated with farming. As shown in
the Exhibit III-5, the level of study in the Sphere has been much more limited than within the
City. This is largely due to the limited number of development proposals in the area.
Implementation of the General Plan, however, could facilitate development within the Sphere, if
these areas are annexed. As a result, impacts to unknown historic resources would be potentially
significant. The City’s survey requirements for historic and prehistoric resources would be
applied for these properties, however, to assure that resources were identified and protected.
With such protective measures, impacts on historic resources would be reduced to less than
significant levels. Therefore, impacts to historic resources as a result of implementation of the
General Plan Update will be less than significant with mitigation.
Impacts to Archaeological Resources
As discussed above, previous cultural surveys have identified approximately 500 archaeological
sites, both historic and prehistoric, throughout the entire General Plan Update Planning Area.
Many of these prehistoric resources are from early Native Americans of the Cahuilla tribe.
Exhibit III-5, shows areas throughout the City Limit that have been assessed for cultural
resources. Vacant lands that have not been surveyed may contain buried archaeological
resources. Future construction activity on these lands, including grading activity, site excavation,
and general construction could potentially result in direct or indirect disturbance or destruction of
archaeological resources. Site surveys are required by the City as part of the entitlement process,
to assess potential harm to these resources. As such, new development projects will be required
to conduct surveys for possible archaeological resources.
The Sphere Planning Areas consist of more rural, undisturbed land which may contain buried
archaeological resources. Due to the lack of development activity, the majority of these areas
have not been previously surveyed. Implementation of the General Plan Update will facilitate
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new development on these lands, potentially impacting undiscovered archaeological resources.
Future construction and development activity in the Sphere, including grading activity, site
excavation, and general construction, could result in direct or indirect disturbance or destruction
of archaeological resources. Site surveys are required by the City as part of the entitlement
process, to assess potential harm to these resources. Development proposals made for these areas
after annexation, should it occur, will be required to conduct cultural surveys as part of the
entitlement process.
With proper mitigation measures, impacts to archaeological resources within the General Plan
Update Planning Area are expected to be less than significant.
Impacts to Paleontological Resources
Implementation of the General Plan Update will facilitate new development throughout the
Planning Area. As shown in Exhibit III-4, the City and its Sphere exhibit varying degrees of
paleontological sensitivity according to soil types. Sediments related to the ancient Lake Cahuilla
beds exhibit the highest paleontological sensitivity. In comparison, granitic rock soils found
along the Coral Mountains, which surround the Cove, have low paleontological sensitivity. New
development activity, including construction, grading, and other site disturbances in moderate
and high sensitivity areas has the potential to impact paleontological resources. Mitigation
measures will be required to reduce paleontological impacts to less than significant levels.
Impacts to Native American Resources
Senate Bill 18 requires contact with local tribes when a General Plan Update is prepared. The
City notified all Tribes listed by the State as potentially having sacred lands in the area, as
required by SB 18. Two letters were received, one from the Cabazon Band, and one from the
Agua Caliente Band. The letters stated that the Tribes have no specific information regarding
cultural resources within or near the General Plan Update Planning Area.28
3. Mitigation Measures
The following mitigation measures will reduce impacts to Cultural Resources to less than
significant levels.
1. The City will continue to pursue government-to-government consultation with pertinent
Native American representatives and tribal organizations, as required by SB 18.
2. All proposed project sites will be surveyed by a qualified archaeologist, historian, and/or
architectural historian, as appropriate, to identify any potential cultural resources that may be
affected, unless existing evidence shows that such survey is unnecessary.
28 “Cultural Resources Technical Report for City of La Quinta General Plan (2010 Update), prepared by CRM
Tech, July 8,2010.
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3. The City will maintain and expand as necessary the existing historical resources inventory to
provide a comprehensive and up-to-date register of known cultural resources in the Planning
Area.
4. New development projects proposed for areas of high sensitivity for paleontological
resources shall be required to prepare paleontological resource surveys as part of the
entitlement processing.
5. A paleontological resource evaluation shall be prepared in conjunction with site specific
geotechnical analysis required for grading and building permits for projects located in low
paleontological sensitivity and undetermined areas. Evaluation should include bore
samplings to understand whether grading and/or building will impact underlying Pleistocene
or older soils.
6. The City will require a paleontological monitor during earth moving activities in high
sensitivity areas.
Mitigation Monitoring and Reporting
A. The Planning Department shall review site-specific historic, archaeological, and
paleontological surveys prepared for new development projects in sensitive areas prior to
entitlement of new development projects.
Responsible Party: La Quinta Planning Department, developer, Professional
Archaeologist/Paleontologist.
Geology and Soils F.
Introduction
This section of the EIR addresses potential impacts associated with geology and soils that may
arise from implementation of the General Plan Update. The existing geologic and soil conditions
within the City and Sphere of Influence are described, and the potential impacts of build out are
assessed.
Thresholds of Significance/Criteria For Determining Significance
The following standards and criteria have been drawn from Appendix G: Environmental
Checklist Form of the CEQA Guidelines. The following factors have been considered to ensure
that the General Plan EIR adequately addresses potential impacts to geology and soils that may
result from the adoption and implementation development of the La Quinta General Plan.
Implementation of the General Plan would have a significant effect on soils and geology if it is
determined that the project will:
a. Expose people or structures to potential substantial adverse effects, including the risk of
loss, injury, or death involving:
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i. Rupture of a known earthquake fault, as delineated on the most recent Alquist-Priolo
Earthquake Fault Zoning Map issued by the State Geologist for the area or based on other
substantial evidence of a known fault.
ii. Strong seismic ground shaking.
iii. Seismic-related ground failure, including liquefaction.
iv. Landslides.
b. Result in substantial soil erosion or the loss of topsoil.
c. Locate the project on expansive soil, as defined in Table 18-1-B of the Uniform Building
Code, creating substantial risks to life or property.
d. Have soils incapable of adequately supporting the use of septic tanks or alternative
wastewater disposal systems where sewers are not available for the disposal of wastewater.
Seismic Hazard Mapping Act
The State of California enacted the Seismic Hazards Mapping Act (SHMA) in 1990. It is
intended to protect the health and safety of the public from seismically induced ground failure,
including ground shaking, liquefaction, and slope stability. The California Geological Survey
(CGS) is responsible for implementing the Act. It is charged with providing local governments
with maps that identify areas susceptible to such hazards.
Alquist-Priolo Earthquake Fault Zoning Act
The Alquist-Priolo Act was enacted in 1972 to mitigate hazards related to surface faulting by
identifying zones where surface fractures have occurred. It establishes Alquist-Priolo Zones to
identify and prohibit construction or development within areas that are at risk of surface
fractures. It is the responsibility of the State Geologist to establish regulatory zones around the
surface traces of active faults and to issue appropriate maps identifying Alquist-Priolo zones.
1. Existing Conditions
This section discusses the physical characteristics of the City and Sphere, as well as community
safety. It also summarizes the geologic and seismic hazards portions of the Technical
Background Report prepared for the General Plan29.
Geologic Setting
The General Plan Update Planning Area is located at the boundary of the Colorado Desert
Province, a low elevation basin extending from the Banning Pass to the U.S. border with
Mexico, and the Peninsular Ranges Province, which is characterized by a series of northwest-
trending Valleys and mountain ranges. The unique landscapes of each of these physiographic
provinces have been formed by diverse geologic and climatic process. Portions of La Quinta are
situated on the Valley floor, rising to the foothills lower slopes of the Santa Rosa Mountains.
29 “Technical Background Report to the Safety Element Update, City of La Quinta, California,” prepared by Earth
Consultants International, July 2010.
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Elevations within the Planning Area generally range from approximately 190 feet below sea
level at the southeastern corner of the Planning Area, to 1,700 feet above sea level in the foothills
of the Santa Rosa Mountains.
The Whitewater River traverses the northern part of the City. It is the primary drainage in the
Coachella Valley, and intermittently drains the surrounding mountains as well as the northern
portion of the Valley. For most of the year, streambeds in the Santa Rosa Mountains are dry.
However, following storms they may carry significant flows that accumulate within a short
period of time.
There are also numerous canals and aqueducts crossing the Planning Area. Ultimately, these
terminate at Lake Cahuilla, a man-made storage reservoir located in the southern portion of the
Planning Area.
In geological terms, the Valley portion of La Quinta is located at the edge of the Salton Trough, a
broad tectonic depression that has been sinking over millions of years and has filled with several
thick sediment layers that form what is now the Valley floor. The trough is physically continuous
from the San Gorgonio Pass to the Gulf of California.
Ancient Lake Cahuilla occupied the area where most of modern La Quinta is located, possibly as
recently as 400 years ago, when it evaporated. At one time, it covered an area of more than 2,000
square miles.
Soils and Geologic Units
Soil Types
There are seven soil units that have been mapped in the Planning Area, each of which is
described below. Exhibit III-6 shows the locations of these soils in the Planning Area.
Alluvial sand and gravel of the Whitewater River (Qg)
Soils in this unit are comprised of very young, unconsolidated alluvium deposited by the
Whitewater River, with crudely bedded sand, silt, gravel, boulders, and debris deposited by
floodwaters. River sediments are highly susceptible to erosion and may be re-distributed and/or
buried by flooding. In general, construction within floodways is limited to roadway crossings or
pipelines. These soils are highly compressible; therefore, construction of such improvements
must include bridge supports that are anchored in underlying, more stable soils. Hazards
associated with these soils include scour from flood flows and damage from large debris, such as
boulders.
Windblown sand (wind-lain dune sand) (Qs)
This is a common soil type in the region, and is mapped all through the northern portion of the
City. Windblown, or Aeolian deposits are generally comprised of reworked alluvium. Silty and
fine- to medium-grained sands are lifted by strong winds that occur frequently in the area, and
deposited to form shifting sand dunes (Qs). This soil unit has a high susceptibility to erosion,
settlement, and collapse.
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Interbedded lacustrine (clay of valley areas) (Ql)
As noted above, the region was the site of Ancient Lake Cahuilla, as well as other large lakes
that inundated the Salton Trough. These soils consist of lacustrine (lake) sediments up to 300 feet
thick, layered with alluvial fan and colluvial sediments deposited from mountain slopes.
Potential for soil collapse of lacustrine soils is considered low given the presence of deeper
sediments from the ancient lakes that underlies the youngest alluvium. Lacustrine soils have high
permeability, except for where they interbed with silt or clay layers, which slow the downward
percolation of water. There is generally low potential for expansive soils, with the exception of
lake deposits with silt and clay near structural foundation elements.
Alluvial deposits (sand of Valley areas) (Qa)
These soils are geologically young and near-surface, often containing organic debris, and have
been rapidly deposited by flash floods. Therefore, engineering issues include compressibility,
and soil collapse, with the introduction of irrigation water into dry soils. These soils are also
highly susceptible to erosion, with moderate to high permeability. They are appropriate for use as
fill after the removal of organic materials and oversized rocks, but for compaction generally
require the addition of water.
In the Planning Area, alluvial deposits generally occur along the base the Santa Rosa Mountains
to the west. Older, more developed portions of La Quinta, which occur downwind of Eisenhower
Mountain, are built on alluvium. Towards the south of the Valley, alluvial soils are interbedded
with fine-grained lacustrine sediments.
Alluvial fan sand and gravel deposits (Qf)
Alluvial fan deposits occur on active fans draining mountain canyons. They consist of poorly
bedded silt, sand, and gravel, with boulders sometimes present in the upper part of the fans.
Younger fans have a somewhat smooth surface, networked with braided ephemeral streams.
Older fans may have a slightly elevated surface divided by embedded stream channels. These
deposits progressively transition into finer-grained alluvial and ancient lake deposits that occur in
the lower Valley.
Because they are typically unconsolidated, younger fan deposits are susceptible to settlement or
collapse, as well as wind or water erosion. Although generally more consolidated, older fan
deposits may have a higher percentage of clay at and near the surface, with potentially expansive
soils.
Landslide deposits (Qls)
There are several large landslides that have been mapped in the Santa Rosa Mountains above La
Quinta. The Martinez Mountain Landslide is located south of the City, and partially encroaches
into La Quinta. It is one of the largest and most spectacular landslides in the area. It occurred in
prehistoric times and is a rock avalanche comprised of coarse debris that was transported nearly
six miles.
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Soils associated with landslides are generally considered unstable and may be compressible,
especially around perimeters, with the addition of increased loads such as deep fill
embankments. In the event of strong ground shaking or undercutting by streams at the toe, they
may be reactivated.
Quartz diorite (hard crystalline rock) (Qd)
This is the oldest geologic unit in the La Quinta area. Hard, crystalline rock forming the
mountains is buried beneath the alluvium. Crystalline rocks vary widely in texture, composition
and physical properties. Rocks underlying La Quinta are “plutonic,” meaning they have
crystallized from the molten state deep within the Earth’s crust. Those forming the mountains in
the Planning Area are comprised of minerals that are most closely associated with quartz diorite.
It is estimated that magma from which this rock crystallized over 65 million years ago.
Crystalline rock is highly durable and has formed the steep slopes and deep canyons within and
above the City. Where not highly weathered, deposits are very hard and cannot be excavated
easily. Typically they are non-water bearing, with low to moderately low permeability, except
where jointed and fractured. These rocks are generally non-expansive, and provide strong
foundation support. Rockfall hazard occurs where slopes are covered by boulders.
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Geologic Hazards in the La Quinta Area
Geologic hazards in the Planning Area include landslides and slope instability, compressible,
collapsible or expansive soils, soil corrosivity, ground subsidence, erosion, and wind-blown
sand.
Slope Failure
Slope failure may affect a relatively small area and often only for a very short time. However, it
can result in substantial damage to property, and can be quite costly. The Planning Area
encompasses foothills and mountain slopes associated with the Santa Rosa Mountains. Where
development occurs at the base of these landforms it may be susceptible to a variety of hazards
associated with slope instability, such as landslides and surficial failure, including soil slips, mud
or debris flows, and rockfalls. In La Quinta this hazard primarily affects more developed areas
located near the base of mountains. Perched on slopes, boulders can result in a rockfall hazard to
development adjacent to these slopes. Hazards may be increased by earthquakes, periods of
intense rainfall, or human activities associated with construction, such as grading and blasting.
A variety of factors influence the stability of the slope, including height, steepness, shear
strength and the orientation of underlying weak layers.
Free-falling or tumbling masses of bedrock that have disconnected from steep canyon walls or
cliffs are called rockfalls or rockslides. Rockfall hazards increase when rock slopes become
extremely steep, such as may occur as a result of erosion or human activities. Strong ground
shaking, intense rainfall, or grading and blasting can generate rockfall or rockslides. In the
Planning Area, rockfall hazard is primarily present for lands at or near the base of boulder-
covered slopes.
Rock types that occur in the Planning Area are generally resistant to landslides. In mountains
above the City, mapping shows several “rock avalanche” landslides. If cut to very steep
gradients, and depending on their overall composition and strength, these rocks may become
susceptible to slope failure.
Surficial failures associated with soil slip may result from strong winter storms when soils have
deposited in canyon sideslopes and in gullies and ravines. They occur most frequently on steep
slopes, which occur in higher hills and mountains within and adjacent to the Planning Area.
The most dangerous and destructive of all types of slope failure is debris flow, also known as
mudflow, mudslide, and debris avalanche. These flows are rapidly moving watery mixtures
containing mud, rock, vegetation, and are capable of transporting very large debris such as
boulders or trees. Debris flows are usually associated with prolonged storms. Within the
Planning Area, lands at the base of moderate to steep slopes or at the mouths of drainage
channels are most vulnerable to debris flows.
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Compressible Soils
Soils that are geologically young (Holocene age), have low density and are of unconsolidated
sediments. They may compress under the weight of fill embankments and structures. These soils
often include recently deposited alluvium, which occurs in the Valley portion of the Planning
Area.
A variety of factors may affect the soil’s overall compressibility. These include soil
characteristics such as texture and grain size, density and moisture and the thickness of the
compressible layer(s), as well as engineering parameters. In addition to the Valley floor, portions
of the Planning Area most likely to contain compressible soils include the Whitewater River, as
well as wind-blown deposits, hillside areas, especially at the base of natural slopes, and within
canyon bottoms and swales. Although older alluvial fan deposits in the Planning Area are
relatively dense, upper layers, which may be disturbed and/or weathered, are typically
compressible. Deep fill embankments, generally more than 60 feet deep, may also compress
under their own weight. Geotechnical analyses and the application of appropriate engineering
techniques are mitigation measures that may be used to reduce potential hazards associated with
compressible soils.
Collapsible Soils
Recently accumulated soils in arid or semi-arid environments may be subject to soil collapse, or
hydroconsolidation. These soils are typically dry and contain tiny voids. If partly supported by
clay or silt, they become rearranged and lose cohesion when inundated. Even relatively light
loads can cause these soils to settle substantially and quickly under these conditions. When
surface water permeates them, differential settlement can occur. Where settlement occurs at or
near buildings, particularly when heavy irrigation takes place near a building foundation,
structures such as walls or foundations may crack.
In the Planning Area, localized settlement can occur where soils such as alluvium or wind-borne
soils have been recently deposited. Hazards associated with collapsible soils can be addressed
through site-specific geotechnical studies and sound engineering and site design.
Expansive Soils
Varying amounts of fine-grained silts and clays within soils may shrink or swell as moisture
content changes. The presence of expansive soils may create pressure that can affect structures
or other surface improvements.
In the General Plan Update Planning Area, the Valley floor is underlain by alluvial sand and
gravel interbedded with fine-grained lakebed deposits such as silts and clays. There may be
considerable variation in the expansion characteristics of these soils after site grading. Typical
soil profiles on older alluvial fan deposits may include substantial amounts of clay material that
would be expected to be moderately expansive.
In general, rock formations in hills and mountains have low expansion characteristics, although
clays with expansive materials may be present in sheared zones within rock. Where engineered
fills near the finished surface include expansive soils, damage may result. This risk may be
minimized by ensuring that surface fill is free of expansive soils, as much as feasible. Surface fill
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may also be pre-saturated as determined by a soil engineer. Other measures include good surface
drainage and efficient irrigation systems that do not result in excessive watering.
Corrosive Soils
Soil and buried metallic structures, such as water mains or elements within building foundations,
may react in a variety of ways involving complex electrochemical and bacteriological processes.
The most common identifying factor for corrosive soils is electrical resistivity. Cumulative
impacts may occur over time, with substantial damage to underground metallic objects where
soils have low resistivity. Corrosive soil characteristics also include high acidity (low pH), high
moisture content, high chloride or low oxygen levels, and the presence of certain bacteria. The
risk of corrosion is also increased where sulfide compounds are present. These compounds may
occur when sulfate-reducing bacteria converts sulfates, which are not directly corrosive to
metals, to soluble sulfides, which can be corrosive to concrete.
On the Valley floor, sediments may be present that are corrosive to metallic objects, such as
pipelines. A corrosion engineer can test soils prior to construction. Other means to reduce risks
associated with corrosive soils may include the use of special cement mixes, specialized coatings
or protective wrapping materials, and specified soil water content.
Ground Subsidence
Ground subsidence occurs when the ground surface gradually sinks or settles, with no horizontal
movement. Subsidence is primarily caused by human activity. The extraction of sub-surface
water, oil or gas in sediment filled Valleys and floodplains are primary contributors. Although
less common, natural forces, such as earthquake movements, can also result in subsidence and
have in some cases resulted in abrupt elevation changes across faults.
The effects of regional subsidence include earth fissures, sinkholes or depressions, and surface
drainage disruption. Certain improvements may be sensitive to slight elevation changes,
including canals, levees, and underground pipelines; these are most at risk from subsidence.
Structures such as wells, buildings, roads and railroads can also be damaged where substantial
subsidence occurs.
When groundwater extraction surpasses supplies, a condition known as overdraft, a loss of
aquifer storage capacity can occur and create subsidence. This condition exists in the Coachella
Valley. Therefore, the regional water management district, Coachella Valley Water District, has
instituted a variety of measures to manage subsidence. These include the use of imported water,
artificially recharging groundwater basins, and reducing pumping of local wells.
The U.S. Geological Survey (USGS) has monitored subsidence rates in the Coachella Valley
over several decades. These data indicate rapid increases in subsidence rates, which is primarily
attributed to groundwater extraction in the Valley.
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Irreversible subsidence can occur when groundwater is removed from clay and silt layers in the
underlying aquifer, creating surface fissures and cracks. In the Coachella Valley, fissures have
been recorded in one instance in La Quinta, in 1948 near the base of the Santa Rosa Mountains.
Subsidence is most typical in valleys where overdraft is an issue.
CVWD is addressing this regional issue in its groundwater management program. The District
has implemented a range of programmatic measures, including groundwater recharge, imported
water, and a variety of water conservation techniques and programs.
Erosion
Climate, topography, soil and rock types, and vegetation are all factors that influence erosion,
runoff, and sedimentation. These issues are relevant to La Quinta given the area’s topography.
Adjacent mountains are composed of fractured bedrock that has undergone rapid geologic uplift.
The region is subject to infrequent but often powerful winter storms that generate high rates of
erosion. Where wildfires have removed vegetation from mountain slopes, erosion risk is further
increased. These conditions are intensified when storms create large volumes of sediment that
flow to areas downslope.
Within the Valley portion of the Planning Area, canyon bottoms and other areas contain soils
that are unconsolidated and most susceptible to erosion. Natural erosion processes may be
accelerated by human activities such as agriculture and development, even where soils are more
consolidated. Grading and clearing activities eliminate protective vegetation, modify natural
drainage patterns, and compress soils. Slopes created by cut and fill may be at greater risk of
erosion than natural slopes. Development also reduces the surface area available for water to
percolate. This increases the risk of downstream sedimentation and flooding.
Development plans for new projects in La Quinta are required to incorporate temporary and
permanent erosion control. Where such projects exceed one acre, developers must obtain
coverage under the Statewide General Construction Permit and the City’s National Pollutant
Discharge Elimination System (NPDES) Permit. Requirements associated with this coverage
include the preparation of a Stormwater Pollution Prevention Plan (SWPPP), Best Management
Practices (BMPs) and in some cases the preparation of a Water Quality Management Plan
(WQMP).
Wind Erosion
Wind erosion is common in flat, bare, dry and sandy areas. Wind erosion damages land and
natural vegetation through sediment transport and re-deposition. These processes result in soil
loss and deterioration of structures and air pollution.
Throughout the Coachella Valley, varying levels of hazards associated with wind-blown
(Aeolian) sand occur, and there are a variety of conditions that contribute to the creation and
transport of sand in the region. These include the orientation of landforms such as hills and
mountains, the nature of the bedrock, the location of the Whitewater River floodplain, slope of
the Valley floor, and sparseness of vegetation on undeveloped lands on the Valley floor. The
characteristic hot, dry desert climate is a major factor, as are precipitation rates. The Valley
receives low amounts of annual rainfall, with the exception of infrequent intense winter storms.
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Much of the Valley, including the Planning Area, is susceptible to wind and wind-blown sand
hazards. A variety of health problems are associated with wind and blowing sand, such as skin
disorders, allergies and respiratory irritation, and eye infections.
While some areas of La Quinta are sheltered at the base of the Santa Rosa Mountains, the
majority of the Planning Area is located with an active wind erosion zone. The northern portion
of the City is underlain by soils that are subject to erosion, as shown on Exhibit III-7. Soils may
be loosened and transported during grading and construction activities. For this reason, routine
site watering or cessation of construction on extremely windy days are used to mitigate
construction impacts.
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Seismic Activity
The majority of Southern California is located at the boundary between the North American and
Pacific tectonic plates, which are moving past each other at varying rates. Most of western
southern California, including the Coachella Valley, is located on the Pacific Plate. This plate is
moving at a rate of approximately 165 feet in 1,000 years (50 millimeters per year), generally in
a northwesterly direction.
The San Andreas Fault marks the boundary between these two plates. This major fault trends
generally northwest to southeast, approximately 4 miles north of the planning area. It
accommodates approximately 60% to 70% of the plate movement described above, while the rest
is distributed among other faults within the San Andreas system as well as those associated with
the Eastern California Shear Zone. As a result, the Planning Area is located in a physical and
geographic area that is susceptible to strong seismic activity.
Measuring Seismic Events
Earthquakes release seismic energy that is measured in terms of intensity and magnitude. Several
factors determine the intensity of ground shaking, including the earthquake’s magnitude,
distance from the epicenter, and soil and rock composition. A variety of logarithmic scales have
been used by seismologists to measure earthquakes.
The most common measure of seismic intensity is the Modern Mercalli Intensity (MMI) scale.
The MMI scale measures damage from partial or total collapse of masonry structures to severe
damage or devastation of underground infrastructure, bridges, overpasses or other improvements.
The Richter Scale measures earthquake magnitude as a function of amplitude of ground motion
at distance from the epicenter, based on a scale from one to ten. A tenfold increase in the wave
amplitude is represented by each increase along the scale.
The seismic moment (Mw) measure, which correlates the size of an earthquake to the amount of
energy released when a fault ruptures, is the measurement system currently favored by
seismologists. Each one-point increase in magnitude corresponds to a 32-fold increase in energy.
The term “Maximum Probability Earthquake” (MPE) is used to reference the largest earthquake
likely to occur on a fault or fault segment within a specified time period. The MPE is used to
assess potential seismic risk in a region, to prepare engineering or emergency plans, and to
develop design parameters and safe construction practices. The preparation of policies and
programs regarding potential earthquake hazards and impacts also reference the MPE.
The California Geological Survey assigns the highest magnitude earthquake a fault is capable of
producing based on physical limitations such as the length of the fault or fault segment. This is
known as the Maximum Magnitude Earthquake (Mmax). Faults that could result in significant
impacts in the La Quinta area are shown on Table III-15. The Table shows that the entire
Southern segment of the San Andreas fault has the potential to generate a magnitude 8.0
earthquake, or the equivalent to a Level X-XI on the Modified Mercalli Intensity Scale.
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Table III-15
Horizontal Peak Ground Accelerations and Seismic Intensities
Fault or Fault Segment
Distance to
La Quinta
(mi)
Distance to
La Quinta
(km)
Magnitude
of Mmax
PGHA (g)
from Mmax
(median)
MMI from
Mmax
San Andreas fault (entire
Southern) 3.4 – 8.8 5.4 – 14.2 8.0 0.50 – 0.34 XII - X
San Andreas (Coachella
segment) 3.4 – 8.8 5.4 – 14.2 7.2 0.50 – 0.36 XI - IX
San Andreas (Coachella + San
Bernardino) 3.4 – 8.8 5.4 – 14.2 7.7 0.6 – 0.41 XII - X
San Andreas (San Bernardino) 17.6 – 28.2 28.4 – 45.4 7.5 0.23 –0.15 IX - VIII
San Jacinto (Anza) 16.3 – 23.4 26.3 – 37.7 7.2 0.21 – 0.15 IX – VIII
Burnt Mountain 15.4 – 26.2 24.8 – 42.2 6.5 0.14 – 0.08 IX - VI
Eureka Peak 16 – 26.7 25.8 - 43 6.4 0.14 – 0.08 IX - VI
San Jacinto (Coyote Creek) 18 –23.8 29 – 38.3 6.6 0.13 – 0.10 IX – VII
Pinto Mountain 28 – 37.8 45.1 – 60.9 7.2 0.13 – 0.09 IX – VII
Pisgah – Bullion 31.5 – 39.5 50.7 – 63.6 7.3 0.12 – 0.09 VIII - VI
Abbreviations: mi – miles; km – kilometer; Mmax – maximum magnitude earthquake; PGHA – peak
ground horizontal acceleration as a percentage of g, the acceleration of gravity; MMI – Modified Mercalli
Intensity.
Several other faults have the potential to generate seismic shaking similar to that experienced in La Quinta
during the 1992 Landers earthquake. Faults that would generate a similar level of shaking include: North
Frontal (both East and West segments, individually), Calico-Hidalgo, Elsinore (Julian segment), Lenwood-
Lockhart-Old Woman Springs, Helendale-South Lockhardt, San Jacinto (San Jacinto Valley segment), San
Jacinto (Borrego segment), Brawley Seismic Zone, Earthquake Valley, and Elmore Ranch. All of these
faults would generate peak ground accelerations in the 0.05 to 0.09 range (median) and 0.08 to 0.16 range
(median plus 1 sigma), with Modified Mercalli intensities in the V to VIII range.
It is estimated that there is a 10% probability that a ground motion of approximately 0.5g will be
exceeded in 50 years near La Quinta City Hall. In the area of the City nearest the San Andreas
fault, in the northeastern most corner of the City, there is a 10% probability that a ground motion
of approximately 0.64g could be exceeded in 50 years. These are moderate to very high levels of
ground shaking, which would be expected to result in moderate to heavy damage, especially to
buildings that are older or poorly constructed.
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Major Faults Affecting La Quinta Planning Area and Vicinity
Earthquakes can result in impacts ranging from significant property damage to the loss of public
services and facilities and the loss of life. The most severe impacts in the La Quinta area would
be expected to result from strong ground shaking associated with earthquakes. Earthquakes and
associated groundshaking can also generate other impacts, such as landslides, damage or
destruction to structures, liquefaction, and settlement. Fires, hazardous materials releases,
disruption of essential facilities and services such as water, sewer, gas, electric, drainage, and
transportation can also occur. Flooding may happen when dam or water tanks fail as a result of
ground shaking.
The most significant faults with potential to affect the General Plan area are discussed below.
The locations of these faults are shown on Exhibit III-8, Faults and Historical Seismicity Map.
San Andreas Fault Zone
The San Andreas, which passes approximately 4 miles northwest of the Planning Area, is
considered the “Master Fault” in Southern California. This is because of the influence it has over
seismic hazards, as well as the frequency and magnitude of earthquakes it generates. The San
Andreas fault extends approximately 690 miles, from the Salton Sea to Cape Mendocino in
northern California. The 2007 Working Group on California Earthquake Probabilities (WGCEP)
estimated that the southern San Andreas fault has a 59% probability of causing an earthquake of
at least magnitude 6.7 (Richter scale) in the next 30 years.
A rupture along the entire southern San Andreas fault, including, from south to north, the
Coachella, San Gorgonio-Garnet Hill, San Bernardino and Mojave segments, with an epicenter
along the San Andreas fault closest to La Quinta represents the worst case scenario for La
Quinta. Such an occurrence would generate peak ground accelerations in the City between 0.5 g
and 1.1 g, which would result in severe to violent ground shaking.
San Jacinto Fault Zone
The San Jacinto fault zone is located between 26 and 38 miles south of the planning area.
Extending approximately 175 miles, it intersects with the San Andreas fault in San Bernardino,
and trends southeasterly toward the Brawley area. South of the U.S./Mexico border it continues
as the Imperial fault. The San Jacinto fault has historically produced more large earthquakes than
any other fault in southern California, albeit none as large as the 1857 and 1906 earthquakes on
the San Andreas fault. WGCEP estimates there is a average 31% probability of all the segments
of the San Jacinto fault rupturing between 1994 and 2024.
The Anza and Coyote Creek segments, respectively, are the segments of San Jacinto fault zone
closest to La Quinta. WGCEP studies (2008) indicate that there is an average recurrence interval
for earthquakes along the Anza segment of 238 years, with the most recent earthquakes
occurring between 205 and 235 years ago. Should a Mw 7.2 earthquake occur on this segment, it
would be expected to generate peak ground accelerations in the Planning area of between about
0.15g and 0.32g.
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Burnt Mountain Fault
The Burnt Mountain fault was unknown prior to 1992; it is one of several of the Eastern Mojave
Shear Zone faults. In 1992 a ground-surface rupture, thought to be a large aftershock of the
Landers earthquake, occurred along a 3.1-mile-length of this fault. Geologic mapping indicates
this fault is approximately 13 miles long and is approximately 15 miles north of the City at its
closest point. It is considered capable of producing a magnitude 6.0 to 6.5 earthquake. Based on
a Mw 6.5 earthquake along this fault, horizontal ground accelerations of between 0.08g and 0.21g
could occur in La Quinta, with higher accelerations in the northern portion of the City, closest to
this fault.
Eureka Peak Fault
The Eureka Peak Fault is approximately 12.5 to 15 miles long and is a right-lateral strike-slip
fault. Along with other faults, it ruptured during the 1992 Landers earthquake, and is thought to
have caused the Joshua Tree earthquake of April 22, 1992. The Eureka Peak fault is considered
capable of generating earthquakes of between Mw 5.5 and 6.8. In the event of a Mw 6.4
earthquake on this fault, estimates indicate it could generate horizontal peak ground accelerations
in the Planning Area of between 0.08g and 0.21g.
Pinto Mountain Fault
This fault occurs approximately 28 miles north-northwest of the city of La Quinta at its nearest
point, at the boundary of the north side of the Little San Bernardino Mountains. Its length is
thought to be between 45 and 56 miles. As defined in the Alquist-Priolo Act, it is considered an
active fault, in that it has ruptured at least four times within the last approximately 9,400 years.
A scenario entailing a 7.2 earthquake on this fault would generate peak horizontal ground
acceleration in La Quinta of about 0.09g to 0.21g. Damage in the City would be characteristic of
MMI intensities of between VII and IX.
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Seismically Induced Geotechnical Hazards
Seismically induced hazards include strong ground shaking and ground failure as a result of
earthquakes. These can result in significant damage to development. The following discusses
potential geotechnical hazards that may occur in the Planning Area.
Groundshaking
Seismically induced ground shaking poses the most potentially significant geotechnical hazard to
the Planning Area. As discussed previously, large earthquakes along regional faults such as the
San Andreas and San Jacinto fault zones have the capacity of generating moderate to severe
ground shaking in the planning area.
There are several factors that determine the effects of ground motion and the degree of structural
damage that may occur. These include earthquake intensity, distance from the epicenter to the
site, composition of soil and bedrock, building design, as well as others. As distance from the
fault along which the earthquake occurs increases, peak ground accelerations and seismic
intensity generally decrease. Local conditions such as soft soils, shallow ground water, and the
presence of ridge tops may amplify the effects of seismic waves and may also result in higher
localized accelerations. There are many tools that local agencies have available to ensure
structural safety from seismic events. These include the Uniform Building Code, California
Building Code, and Unreinforced Masonry Law. These are further discussed under Mitigation of
Earthquake Hazards, below.
Groundshaking can result in various types of ground failure, including liquefaction and slope
failure, which are among the most destructive. Others, such as landslides, seismically induced
settlement, deformation of sidehill fills, and ridgetop fissuring and shattering can occur. These
are discussed categorically below.
Liquefaction
Liquefaction is a sudden increase in water pressure between soil grains that causes soils to take
on the qualities of a liquid or semi-viscous substance. It occurs when groundshaking occurs over
a relatively long duration, with intensity exceeding 0.2 g. Soils that are susceptible to
liquefaction are generally loose, unconsolidated, soils with relatively shallow groundwater
depths (50 feet or less). Liquefaction can substantially decrease soil shear strength, causing
settlement to occur and resulting in damage to structures. Structures may sink or tilt when
bearing capacity is weakened. Ground undulation, lateral spreading or displacement, and flow
failures or slumping may also take place.
Given its proximity to major, active regional fault systems, the entire Planning Area is subject to
strong ground shaking. Loose, unconsolidated soils occur primarily on the Valley floor portion
of the Planning Area. The southeastern area of the City and the entire eastern Sphere are
susceptible to liquefaction due to both shallow groundwater and soil type. Liquefaction potential
in this area is moderate where groundwater is at depths of 30 to 50 feet below the surface. It
ranges to high where groundwater is found at depths 30 feet and higher. Areas of the Planning
Area that are susceptible to liquefaction are shown on Exhibit III-9.
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Landslides and Rockfall
Strong ground motion from earthquakes can exacerbate unstable slope conditions, causing
landslides and rockfall. As described previously, landslide vulnerability is a function of a variety
of geologic and physical conditions.
Portions of the Planning Area wherein development is located downslope of mountain slopes and
steep canyon walls are considered most susceptible to rockfall. This includes much of the older,
more developed areas of the City, which are surrounded on three sides by mountains comprised
of granitic rock. These areas are shown on Exhibit III-9.
Seismically Induced Settlement
When strong ground shaking occurs, it can cause soils to become more tightly packed, collapsing
voids and pore spaces, and reducing the thickness of the soil column. Soils that are especially
subject to this risk include loose and unconsolidated sediments, such as young alluvial and wind-
deposited soils, as well as artificial fill that has not been properly compacted during construction.
As shown on Exhibit III-6, these soil units (mapping units Qa, Qa/Ql and Qs) occur throughout
many portions of the Planning Area.
Deformation of Sidehill Fills
Where roadways or level building pads are constructed on natural slopes, they may require
artificial fill wedges, also called sidehill fills. Differential settlement can also occur in the wedge
itself, or in building of the slope face. In the Planning Area, there is potential for sidehill fill
deformation in mountains and hillsides. Construction in these areas is most commonly required
when service roads and foundation pads are to be cut into the side of a slope for improvements
such as above-ground water tanks, or to create wider roads or building pads. The potential for
this hazard may be determined through site-specific geotechnical investigations. Implementing
sound engineering principles and practices will minimize this risk.
Ridgetop Fissuring and Shattering
Strong ground shaking can amplify seismic energy, and result in shattering surface soils on steep,
narrow ridgelines or linear fissures at ridge crests. Particularly susceptible are structures located
at high ridges bordered by steep slopes. Development along the ridgelines of the Santa Rosa and
San Jacinto Mountains within and bordering the Planning Area is generally limited to above-
ground water storage tanks. To mitigate these hazards, avoiding development along ridgelines is
indicated. Site-specific geotechnical evaluations, re-contouring topography to reduce conditions
that may contribute to amplification, and proper grading techniques may reduce this hazard and
should be implemented where any development or improvements are considered.
Seiche
Standing wave oscillations, or seiches, can occur in enclosed or partially enclosed water bodies
of shallow to moderately shallow depth. Waves continue in a back and forth motion after the
originating force has ceased. Seiches are caused by tides, wind, or seismic events, and may occur
in reservoirs, lakes, ponds, or swimming pools. The frequency of the seismic waves, distance and
direction from the epicenter, style of the fault rupture (dip-slip or strike-slip) and the design of
the enclosed water body all affect seismically induced seiching. Although seismically induced
seiche waves are generally less than 1.7 feet high, heights of up to 6.6 feet have been reported.
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The Planning Area contains numerous lakes, ponds, and reservoirs that may be subject to seiches
as a result of ground shaking, including Lake Cahuilla, the recharge basins south of La Quinta,
and smaller golf course lakes. As noted above, the variety of factors that affect the potential
seiche wave amplitude from these waterbodies make them difficult to predict.
Seiches may also result in damage to water storage reservoirs, such as those that occur within
and adjacent to the Planning Area. The Coachella Valley Water District has indicated that their
facilities have been constructed or updated based on criteria as set forth by the American Water
Works Association, which developed them following the 1992 Landers-Big Bear sequence and
the 1994 Northridge earthquakes. These issues are further discussed in the Section III-H,
Hydrology.
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2. Project Impacts
As the General Plan Area builds out, the potential for a number of geologic and seismic hazards
will increase. New development will result in construction of structures and infrastructure that
could expose persons and property to geological hazards in the event of a seismic event. The
following discusses potential geological impacts associated with build out of the General Plan.
Geological Conditions
Seismicity
The City and Sphere are subject to potentially moderate to severe ground shaking as a result of
earthquakes along the San Andreas Fault Zone and associated faults in the area. Although no
active or potential active faults occur in the Planning Area, geological analyses conducted for the
General Plan indicates that the Planning Area could experience moderate to very high ground
shaking from earthquakes along the San Andreas Fault. These levels of ground shaking have
potential to cause moderate to heavy damage, especially to older and poorly constructed
buildings. Strong ground shaking can also result in indirect hazards, including slope instability,
liquefaction, settlement, landslides, and flood inundation. A variety of other hazards can also
occur, which are no less destructive. These may include urban fires, failure of water storage or
containment structures, such as levees, dikes or reservoirs, and toxic chemical releases.
Post-earthquake conditions may be worsened by damage to infrastructure and utility systems.
Roadways in the region and Planning Area may fail, thus restricting access into and through the
area, including by emergency response vehicles and personnel. Telephone, gas, energy, and
water may be substantially affected, impeding affect efforts to improve conditions and make
available necessary support such as fire suppression, and access to potable water as well as
heating and cooling. In addition, operations at critical facilities such as hospitals may be
impacted, with reduced functionality for a period of time depending on the intensity of the
earthquake.
Smaller structures may also be damaged by seismic activity. Unreinforced masonry buildings are
at the greatest risk. Foundations may shift, resulting in exposed power lines, gas leaks, and fires,
and exposed power lines. All new buildings in La Quinta must utilize reinforced masonry.
Further, new construction must comply with the Uniform Building Code (UBC), and it is
expected that this compliance will allow structures to resist major earthquakes without
collapsing, even if structural damage occurs. State law requires that unreinforced masonry
buildings be retrofitted, and the City has a mandatory mitigation program. In La Quinta, five of
seven unreinforced masonry buildings have been retrofitted. The two remaining buildings are
adobe structures; although still unmitigated, they are vacant and are not being used.
Liquefaction
Several areas in the City and Sphere have potential to be impacted by liquefaction, which is a
loss of shear strength when fine-grained soils become saturated. Damage can result when
buildings tilt or sink. There is a moderate potential for liquefaction in the southeastern portion of
the Planning Area, and a high potential in the eastern Sphere. To mitigate for this risk, site-
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specific studies should be conducted prior to any proposed development in areas considered to be
susceptible to liquefaction as mapped in the General Plan.
Seismically Induced Slope Instability
Areas at risk due to seismically induced slope instability occur within the southern and western
portions of the Planning Area near the base of steep slopes associated with the Santa Rosa and
San Jacinto Mountains. These areas have been mapped and are shown in the General Plan as
well as this EIR. For the most part, development is expected to be limited within these areas.
Nonetheless, lands downslope of mountain slopes and hillsides may be susceptible to risks
associated with landslide and rockfall. Therefore, as required in the Seismic Hazards Mapping
Act, future development in areas mapped as being at risk from slope instability should be
evaluated according to procedures recommended by the Division of Mines and Geology.
Seismically Induced Inundation
The Planning Area is not within an inundation area for a dam under the jurisdiction of the
California Division of Dam Safety. Potential for seismically induced inundation in the Planning
Area may occur in the event of levee failure along the Coachella Valley Stormwater Channel, the
Coachella Canal and Lake Cahuilla. Above-ground water storage reservoirs in the Planning Area
contain large quantities of water. If these structures are damaged in an earthquake, downslope
areas are at risk of flooding. Mitigation for these potential hazards are provided in Section III-H,
Hydrology, and include regular monitoring of these facilities to ensure their structural integrity.
Soil Characteristics
There are eleven soil types found in the City and Sphere of Influence areas, which exhibit a
variety of characteristics, of which some may influence geological hazards including slope
instability, collapsible, compressible, and expansive soils, corrosivity, ground subsidence, and
erosion. Soil structure also affects drainage, infiltration, and other hydrological processes. These
impacts are further analyzed in Section III-H of this EIR.
Development at the base of foothills and slopes of the Santa Rosa Mountains may be subject to
slope instability such as rockfall, and to a more limited extent landslides, debris flow and
rockslide. These risks are expected to increase as a result of seismically induced ground shaking.
Mitigation includes limiting development at the base of steep slopes, as well as measures that are
available to property owners such as installation of retaining structures and landscaping to
stabilize hillsides, and avoiding heavy irrigation.
Alluvial and windblown soils occur in various portions of the Planning Area. Windblown sand
deposits occur in the northern City and Sphere, while soils associated with alluvial fan deposits
occur throughout the southern and western/northwestern portions of the City. Soils associated
with alluvial (water) and aeolian (wind) processes are subject to loss of cohesion when saturated,
which may result in collapse and/or hydroconsolidation. Structures built on these soils may be
damaged as a result. Site-specific geotechnical studies should be conducted in areas where these
soils are present to analyze potential risks and provide specific engineering recommendations.
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Much of the Planning Area is underlain by lacustrine deposits associated with ancient Lake
Cahuilla. These soils contain varying amounts of clay and silt, which may be expansive.
Shrinking and swelling can result in damage to structures and other surface improvements.
Appropriate site design incorporating good surface drainage and other engineering techniques
are used to mitigate this hazard.
Ground subsidence, where in the ground surface sinks or settles due to extraction of groundwater
or oil and gas. Substantial and sudden elevation changes may occur during seismic ground
shaking, and can result in damage to canals, pipelines and drainage improvements. Subsidence
is a regional issue in that it is thought to be related to reductions in groundwater supplies in the
aquifer. It is being addressed through Coachella Valley Water District water management
programs, including groundwater recharge and water conservation programs.
Unconsolidated soils occur in many areas of the City and Sphere and are particularly subject to
erosion, including wind erosion. Erosion can result in soil loss and diminish soil productivity.
Wind erosion, which occurs through much of the Valley, including the Planning Area, affects
overall air quality, health, and can result in damage to structures. Much of the Planning Area is
within an active wind erosion zone. Mitigation measures include installation of wind barriers
and soil watering at construction sites. Erosion control measures are required for projects in the
Planning Area. These issues are also addressed in Section III-C, Air Quality.
3. Mitigation Measures
1. The City shall periodically confer with the California Geological Survey, Riverside County,
neighboring communities, and other appropriate agencies to improve and routinely update
the database of local and regional geologic conditions, including seismic and geotechnical
hazard in the General Plan Area.
2. The City shall continue to require that development in areas subject to rockfall, landslide,
liquefaction and/or other geotechnical hazards prepare detailed geotechnical analyses that
include mitigation measures intended to reduce potential hazards to less than significant
levels.
3. The City shall continue a cooperative agreement with the County Geologist, State Geologist,
or contract state-certified geologist and/or geological engineer to review and determine the
adequacy of geotechnical, fault hazard studies and/or soils studies for proposed projects in
the General Plan Area, and to enforce the implementation of mitigation measures.
4. The City shall require that development in areas subject to collapsible or expansive soils
conduct soil sampling and laboratory testing and implement mitigation measures that
minimize such hazards.
5. The City shall require that all new structures be built in accordance with the latest version of
the California Building Code (CBC).
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6. The City shall continue to encourage that structures that pose a safety threat due to
inadequate seismic design are retrofitted or removed from use. The City shall encourage all
other property owners to seismically upgrade their properties.
7. The City shall consult and coordinate with California Geological Survey, Coachella Valley
Water District and other appropriate agencies to support and participate in local and regional
efforts at groundwater conservation and recharge in order to minimize potential impacts of
subsidence due to groundwater extraction, including the periodic monitoring of groundwater
levels and surface elevations in the City.
8. The City shall coordinate and cooperate with public and quasi-public agencies to ensure that
major utilities shall continue to be functional in the event of a major earthquake.
Mitigation Monitoring and Reporting
A. During site preparation for any project, the City Engineer and/or Building and Safety
Department staff shall visit the site to assure compliance with applicable conditions of
approval, City ordinances, and erosion control plans.
Responsible Parties: City Engineer, Building and Safety Department, project developer,
grading contractor.
B. Subsequent to preparation of final development plans and specifications and prior to grading
and construction, the Geotechnical Consultant and/or the City Engineer shall review
foundation plans to confirm compatibility with site-specific geotechnical conditions and
conformance with the recommendations contained herein. The need for additional subsurface
exploration shall be determined on a project-by-project basis.
Responsible Parties: City Engineer, Geotechnical Consultant.
C. Rough grading shall be performed under geological and/or engineering observation by the
Geotechnical Consultant and the City Engineer, accordingly, as appropriate.
Responsible Parties: City Engineer and Geotechnical Consultant.
Hazards and Hazardous Materials G.
Introduction
The City of La Quinta is an urbanized area within the Coachella Valley. With any urbanized
region, the potential for exposure to hazards and hazardous material is always prevalent due
commerce and industrial activities, transportation and distribution of products, and use of
hazardous materials. La Quinta is not immune to these hazards, as numerous business and
households use hazardous materials for commerce and daily living, and due to the constant flow
of truck and rail traffic transporting hazardous materials through the City and region. Other
hazards to residents include the presence of airports, and presence of wildfire zones. This section
assesses impacts associated with hazards and hazardous materials on new growth likely to occur
as a result of implementing the General Plan Update. It also provides mitigation measures to
reduce hazardous impacts on existing and future residents.
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Thresholds of Significance/Criteria for Determining Significance
Article 5, Section 15064 of the CEQA Guidelines provides guidance for determining the
significance of the environmental effects caused by a project. Appendix G of the CEQA
Guidelines provides a list of environmental factors that potentially may be affected by
completion of a project. Build out of the La Quinta 2035 General Plan Update would have a
significant effect from hazards or hazardous materials if it is determined the plan will:
a) Create a significant hazard to the public or the environment through the routine
transport, use, or disposal of hazardous materials.
b) Create a significant hazard to the public or the environment through reasonably
foreseeable upset and accident conditions involving the release of hazardous materials
into the environment.
c) Emit hazardous emissions or handle hazardous or acutely hazardous materials,
substances, or waste within one-quarter mile of an existing or proposed school.
d) Be located on a site which is included on a list of hazardous materials sites compiled
pursuant to Government Code Section 65962.5 and, as a result, would it create a
significant hazard to the public or the environment.
e) For a project located within an airport land use plan or, where such a plan has not
been adopted, within two miles of a public airport or public use airport, would the
project result in a safety hazard for people residing or working in the project area
f) For a project within the vicinity of a private airstrip, would the project result in a
safety hazard for people residing or working in the project area.
g) Impair implementation of or physically interfere with an adopted emergency response
plan or emergency evacuation plan.
h) Expose people or structures to a significant risk of loss, injury or death involving
wildland fires, including where wildlands are adjacent to urbanized areas or where
residences are intermixed with wildlands.
1. Existing Conditions
Hazardous Materials Management
Hazardous waste is any liquid, solid, gas, or sludge that is potentially dangerous to human health
and the environment, including everyday commercial products, such as pesticides, cleaning
fluids, and household sprays, as well as byproducts of manufacturing processes. The United
States Environmental Protection Agency (EPA) has classified hazardous waste into four types of
hazardous waste including listed wastes, characteristic wastes, universal wastes, and mixed
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wastes.30 Listed wastes include wastes from common manufacturing and industrial processes,
waste from specific industries such as petroleum refining or pesticide manufacturing, and
discarded commercial products. Characteristic wastes include non-listed wastes that exhibit
ignitability, corrosivity, reactivity, and toxicity. Universal wastes include items such as batteries,
mercury-containing equipment, and fluorescent lamps and bulbs. Mixed wastes contain
radioactive and hazardous waste components. All hazardous waste poses a threat to humans and
the environment, and therefore is regulated by federal, state and local programs.
Federal Programs
The EPA has been given authority and responsibility to regulate hazardous waste by the
Resource Conservation and Recovery Act of 1976 (RCRA). Through the Act, the EPA is
responsible for monitoring the generation, transportation, treatment, storage, and disposal of
hazardous waste. Amendments to the RCRA, including the 1984 Federal Hazardous and Solid
Waste Amendments, and those established in 1986, forced the EPA to increase enforcement of to
underground storage tanks for petroleum and other hazardous substances, focus on waste
minimization programs, such as phasing out hazardous wastes from landfills, and finally
mandating corrective measures regarding the release of hazardous waste.31
The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA),
known as Superfund, is another federal act enacted on December 11, 1980. CERCLA created a
tax on chemical and petroleum industries to help fund cleanup of abandoned and uncontrolled
hazardous waste sites. The Act is also responsible for establishing the National Priorities List,
which lists nationwide hazardous waste sites that are a priority for EPA cleanup. As of December
6, 2010, there are no Superfund sites located in La Quinta or the Sphere of Influence.32
In October 17, 1986, CERCLA was amended by the Superfund Amendment and Reauthorization
Act (SARA). SARA provided important changes to CERCLA, including increasing the size of
the cleanup trust fund, encouraging more citizen participation on cleanup measures, increased
State involvement in the Superfund program, and providing more innovative treatment
technologies for cleaning up hazardous waste sites. SARA also revised the National Ranking
System, which is used by the EPA to assess whether a hazardous waste site should be placed on
the National Priorities List. As of December 6, 2010, there are no Superfund sites listed on the
National Priorities List located in La Quinta or the Sphere of Influence.33
More recent EPA efforts and responsibilities for managing hazardous waste include management
of wastes from homeland security incidents. The Waste Management for Homeland Security
Incidents requires EPA to provide technical support to Federal, state, local, and tribal authorities
on waste management and cleanup efforts resulting from natural disasters, terrorist attacks, major
accidents, and disease outbreaks. The main responsibility of the EPA is to promote pre-planning
efforts to deal will hazardous waste disasters and encourage various stakeholders to prepare for
30 “Wastes-Hazardous Waste-Waste Types”, http://www.epa.gov/waste/hazard/index.htm, accessed December 6,
2010. 31 “Wastes-Hazardous Wastes”, http://www.epa.gov/waste/hazard/index.htm, accessed December 6, 2010. 32 “CERCLA Overview”, http://www.epa.gov/superfund/policy/cercla.htm, accessed December 6, 2010. 33 “CERCLA Overview”, http://www.epa.gov/superfund/policy/cercla.htm, accessed December 6, 2010.
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natural and man-made disasters. The EPA is also required to review emergency response plans
for Federal agencies, and participate in exercises with Federal, state, local and tribal emergency
responders.
State Programs
The California Certified Unified Program Agencies, or CUPA, is a collection of state and
regional agencies in charge of regulating hazardous waste. They are responsible for the
administration, permits, inspection and enforcement of various environmental and emergency
management programs, including the Underground Storage Tank Program, the Aboveground
Petroleum Storage Act Program, Hazardous Materials Release Response Plans, and Hazardous
Waste Generator and Onsite Hazardous Waste Treatment Programs. The California
Environmental Protection Agency (Cal/EPA) is responsible for administrating and certifying the
CUPA’s. Two state agencies that are also heavily involved with CUPA activities include the
California Department of Toxic Substances Control (DTSC) and the State Water Resources
Control Board (SWRCB).
The California Department of Toxic Substances Control (DTSC) is responsible for protecting
public health and environment from the two millions of hazardous waste generated each year in
California. They regulate under the authority of the federal RCRA of 1976 and the California
Health and Safety Code. The DTSC operates a variety of programs including the following:
-Overseeing site cleanups at improperly managed waste sites
-Ensuring those who generate, handle, transport, store and dispose of hazardous waste do
so properly.
-Enforcement actions against those who fail to manage hazardous waste appropriately.
-Exploring and promoting pollution prevention and encouraging reuse and recycling.
-Evaluating soil, water and air samples at sites and developing new analytical methods
-Practicing other environmental sciences, including toxicology, risk assessment, and
technology development.
-Involving the public in DTSC’s decision-making.
DTSC is required to compile and update each year, or as appropriately, a list of hazardous waste
sites pursuant to Section 65962.5(a). The DTSC has created the EnviroStor database of
properties throughout California that may be contaminated. There are no hazardous waste sites in
La Quinta or Sphere of Influence that are listed pursuant to Section 65962.5(a). The closest listed
site is the Foster-Gardner facility in Coachella, located south of Avenue 50 between Highway 86
and Highway 111.34
The State Water Resources Control Board (SWRCB) is responsible for regulating wastewater
discharges to surface waters and groundwater. This includes discharges from all construction,
industrial, municipal, and agricultural activities. The SWRCB delegates these responsibilities to
various regional water quality control boards throughout California. La Quinta falls under the
jurisdiction of the Colorado River Basin Regional Water Quality Control Board, Region 7. The
Colorado River Basin Regional Water Quality Control Board is responsible for overseeing
34 Cortese List: Section 65962.5(a) http://www.calepa.ca.gov/sitecleanup/corteselist/SectionA.htm
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corrective actions associated with leaks and improper disposal from underground storage tanks,
such as gas station tanks, and provides assistance to County of Riverside Department of
Environmental Health on underground storage leaks.
Regional Programs
The Riverside County Department of Environmental Health (DEH) provides programs and
services related to protecting public health, safety and the environment. Within the DEH are two
divisions, including the District Environmental Service, and the Environmental Protection and
Oversight. The Environmental Protection and Oversight Division (EPO) is responsible for
handling and regulating hazardous materials, land use, water systems, underground storage
tanks, solid waste and business emergency plans. The Department of Health is responsible for
managing a list of all hazardous waste generators in the County. As of December 8, 2010, La
Quinta has 50 generators of hazardous waste. Generators include golf courses, gas stations,
cleaners, grocery stores, car dealerships and city maintenance facility yards.
Emergency response in La Quinta involves numerous state, regional, local, and non-profit
agencies whose goal is to prepare local residents for emergencies caused by natural or human
incidents. The State of California passed the California Emergency Services Act in 1970 to
provide the basic legal authorities for emergency management in the State. The Act created the
Governor’s Office of Emergency Services (OES), which serves as the lead agency for emergency
management and to organize all levels of government, businesses, community organizations and
volunteers to deal with local emergencies. The County of Riverside operates the Office of
Emergency Services through Riverside County Fire Department. Riverside County OES is
responsible for mitigation, preparedness, response and recovery activities from hazards and
threats occurring in Riverside County.35
Local Emergency Response
The City of La Quinta’s Emergency Services Division is responsible for the community’s
preparedness and response to natural and manmade disasters and emergencies. The City has
prepared the Emergency Operations Plan to plan and prepare for emergencies.
La Quinta has also established Code Red, which is an ultra high speed telephone communication
service that provides emergency notifications to local residents during emergencies. The City is
also involved in the Community Emergency Response Team (CERT) program, which educates
volunteers in the community about disaster preparedness and trains them in basic disaster
response skills. The CERT group is organized to support the City of La Quinta during
emergencies or disasters.36
Hazardous Waste Transportation
The General Plan Update Planning Area is near four major transportation routes commonly used
for transporting hazardous waste. The Union Pacific Railroad and Interstate 10 are located
approximately 2.5 miles north of the City boundary. The Union Pacific Railroad runs adjacent to
35 Office of Emergency Services, http://www.rvcfire.org/opencms/functions/oes/, accessed December 17, 2010. 36 “Emergency Services”, http://www.la-quinta.org/Index.aspx?page=80, accessed December 13, 2010.
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Interstate 10. Approximately 16% of goods carried by Union Pacific trains are chemical goods,
which may include hazardous waste.37 Highway 111 runs through the northern portion of the
Planning Area, between Washington and Jefferson Street. Finally, State Route 86 is located east
of La Quinta, and provides regional access to the Imperial Valley.
Hazardous waste cleanup on transportation routes is the responsibility of various state and
federal agencies. Caltrans has created the Hazardous Waste Management program to assist local
districts statewide with management and cleanup of hazardous materials encountered on roads
that are under Caltrans responsibility.38 The California Highway Patrol (CHP) and the US
Department of Transportation are responsible for regulating the shipment of hazardous waste by
requiring appropriate labeling, packaging, and loading of hazardous materials. The CHP also
requires motor carriers and drivers involved in transporting hazardous materials to obtain a
hazardous materials transportation license.39 The United State Department of Transportation has
created the Pipeline and Hazardous Materials Safety Administration Office of Hazardous
Materials Safety (OHMS) to ensure safe transport of hazardous materials by air, rail, highway
and water. 40
Existing Public and Private Airports
The General Plan Update Planning Area is located near two airports, including the Bermuda
Dunes Airport and the Jacqueline Cochran Regional Airport. The Bermuda Dunes Airport is a
small privately owned airport located north of the Planning Area, just south of Interstate 10, and
west of Jefferson Street in the Bermuda Dunes community. The Bermuda Dunes Airport has one
east-west runway measuring approximately 5,000 feet in length. The airport averages
approximately 110 flights a day.41
The Jacqueline Cochran Regional Airport is a public airport located just east of the Planning
Area, east of Harrison Street and between Airport Boulevard on the north and Avenue 60 on the
south. The airport is a general aviation airport and handles approximately 209 flights a day.
There are two runways, including Runway 17-35, which is an 8,500 foot north-south runway,
and Runway 12-30, which is a smaller 4,995 foot northwest-southeast runway. The majority of
flights are from single engine aircraft, and there are no commercial flights at the airport. The
airport houses a variety of private, corporate, and charter aircrafts that accommodate business
travelers, tourists, and residents.42
37 Union Pacific 2009 Annual Report” www.up.com, accessed December 17, 2010. 38 “Caltrans Hazardous Waste Management”, http://www.dot.ca.gov/hq/env/haz/, accessed December 17, 2010. 39 “Publications”, www.chp.ca.gov, accessed December 17, 2010. 40 PHMSA, http://www.phmsa.dot.gov/hazmat/about, accessed December 17, 2010. 41 Bermuda Dunes Airport, http://bermudadunesairport.com/, accessed December 17, 2010. 42 “Airport Operational Statistics” http://www.rcjcra.com, accessed December 17, 2010.
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Fire Hazards
Fire hazards exist where wildland areas are adjacent to or are intermixed with urbanized areas.
Many of these wildland areas include rugged topography with highly flammable vegetation. La
Quinta is situated at the base of the Santa Rosa Mountains, however, these areas are considered
low wildfire zones. The open space and wilderness areas on the western portion of the City are
made up primarily of Granitic rock and sparse desert vegetation. Therefore, there is limited
vegetation to burn that could cause a major wildfire. The flat urbanized areas of La Quinta are
considered very low wildfire areas.
2. Project Impacts
Implementation of the General Plan Update will facilitate new growth and development across
the City and the Sphere. Increased growth will not only result in an increased population
susceptible to hazards and hazardous materials, but will include businesses and development
projects that use, store, and/or transport hazardous material. As such, build out of the proposed
General Plan has the potential to increase the number of people that are susceptible to hazards
and hazardous materials in the Planning Area.
Transport of Hazardous Material Impacts
The Planning Area, as previously mentioned, is located near a network of roads, highway, and
rail lines that carry hazardous materials on a daily basis. New growth and development
facilitated by the General Plan Update will have the potential to increase populations living in
and around these routes. Although the primary travel corridors are located north of the Planning
Area, accidents and spills that occur during the transport of hazardous materials have the
potential to affect the La Quinta General Plan area.
Hazardous materials are highly regulated by various government agencies, such as Caltrans, the
California Highway Patrol, and the US Department of Transportation, and cleanup and
containment of these accidents is monitored by these same agencies. Emergency evacuation and
response plans, such as Code RED, are already developed in La Quinta to provide automated
notification to residents during an emergency, including hazardous waste spills.
The General Plan Update provides commercial and light industrial land use designations,
particularly the Sphere, that will potentially increase the amount of hazardous materials
transported throughout the area.
Cleanup of hazardous materials, and emergency evacuation response plans are already in place.
As such, significant hazards to the public or the environment through the routine transport, use,
or disposal of hazardous materials as a result of implementation of the General Plan Update is
expected to be less than significant.
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Hazardous Material Release Impacts
Household Hazardous Waste
The General Plan Update proposes approximately 8,114 additional residential units in the City
Limits, and 20,699 new units within the Sphere of Influence. These new residential uses have the
potential to use and store household cleaning supplies, chemicals, batteries, fluorescent bulbs,
and other potentially hazardous materials. The amount of hazardous materials used by these new
residential uses will be typical of what is found within existing neighborhoods throughout the
region. The relatively small amount of hazardous materials and chemicals found in households
may pose a minimal danger to the household during a spill or accidental release, however these
household spills and accidents are not expected to create significant hazards. Hazardous waste
centers throughout the Coachella Valley, including the Burrtec Waste and Recycling Center in
Palm Desert, and the household hazardous waste facility in Palm Springs, are available for
residents to dispose of household hazardous waste.
Non-residential Hazardous Materials
The General Plan Update also proposes new commercial, industrial, and institutional uses that
will potentially use, store, and transport hazard materials. These uses, such as gas stations, dry
cleaners, assembly plants, and mechanical shops rely on hazardous materials for everyday
business. The General Plan Update proposes approximately 3,218,039 square feet of additional
commercial uses in the City, 2,458,797 square feet of additional commercial in the Sphere of
Influence, 611,408 square feet of new industrial/light manufacturing uses in the Sphere of
Influence, and approximately 195 acres of new community facilities. New golf courses
throughout the Planning Area may also use and store hazardous materials, such as pesticides and
fertilizers.
All commercial, industrial and municipal generators of hazardous materials are regulated by
federal, state, and local agencies regarding the proper use, disposal and cleanup of hazardous
materials. The Riverside County Department of Health is responsible for managing a list of all
hazardous waste generators in the County. New hazardous waste generators that locate in the
Planning Area will be required to abide by County Department of Environmental Health policies,
and register on the hazardous waste generator list. This list provides residents and public officials
information as to where hazardous materials are located throughout La Quinta.
With the continued implementation of federal, State and local regulations and programs, these
impacts will be less than significant.
Impacts from Hazardous Materials Sites
The General Plan Update Planning Area is not located on the “Cortese” list of hazardous
materials sites compiled pursuant to Government Code Section 65962.5, and managed by the
California Environmental Protection Agency. The closest active hazardous materials site in the
region is located on the Jacqueline Cochran Regional Airport located east of the Planning Area.
Hazardous materials at this site are associated with the airport facilities, as well as historic Army
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and Navy uses. 43 No new development throughout the Planning Area will be located on
hazardous materials sites pursuant to Government Code Section 65962.5. As such, there will be
no impact related to new populations being located on hazardous materials sites.
Airports and Associated Hazards Impacts
The Jacqueline Cochran Regional Airport is immediately adjacent to the eastern boundary of the
Sphere of Influence. As a result, aircraft using the airport may fly over the Planning Area.
The Riverside County Airport Land Use Commission has prepared the Riverside County Airport
Land Use Compatibility Plan, which provides policies for Airport Influence Areas for most of
the airports in the County. Eastern portions of the La Quinta Planning Area are located within the
Jacqueline Cochran Airport Influence Area Zone D and E of the Compatibility Plan. A portion of
the Planning Area is located in Zone C, with a very small area in Zone B1. New development
within the eastern boundary of the Sphere of Influence will need to abide by Compatibility Plan
polices and land use regulations. Land uses such as schools, hospitals, and nursing homes are
discouraged in Airport Compatibility Land Use Zone D, and the number of residential dwelling
units is regulated in this zone. Within Zone E, there are no residential or commercial restrictions,
however prohibited uses include those that create hazards to flights, including tall objects, visual
and electronic forms of interference, and developments that attract birds, such as landfills.44
The General Plan Update proposes non-residential land uses, including both industrial and
commercial uses within Zone D, and residential uses are proposed in Zone E. These uses are
allowed according to the Compatibility Plan. Therefore, hazards related to the Jacqueline
Cochran Regional Airport will have a less than significant effect on development within the
Planning Area.
The General Plan Update Planning Area is also near the Bermuda Dunes Airport. This privately-
owned public use airport is located approximately 1.5 miles north of the northern Sphere of
Influence and City limit, along Interstate 10 west of Jefferson Street. The 5,000-foot runway is
oriented in an east-west direction, and approaches and takeoff patterns generally do not affect
any portion of the Planning Area.45 According to the Riverside County Airport Land Use
Compatibility Plan, the far northern portions of La Quinta, including the northern Sphere of
Influence, are located primarily in Compatibility Land Use Zone E (a portion of Compatibility
Zone D is in the City of La Quinta, but this area has already been developed with housing). As
previously mentioned, there are no residential or commercial restrictions in Zone E; however
prohibited uses include those that create hazards to flights, including tall objects, visual and
electronic forms of interference, and developments that attract birds, such as landfills.46 Proposed
land uses within Zone E are compatible with the Bermuda Dunes Compatibility Plan. Therefore,
43 “Hazardous Waste and Substances Site List”, www.envirostor.dtsc.ca.gov, accessed January 14, 2011. 44 “Riverside County Airport Land Use Compatibility Plan; Volume I”, prepared by Mead & Hunt, October 14,
2004. 45 Bermuda Dunes Airport, http://bermudadunesairport.com/, accessed December 17, 2010.
46 “Riverside County Airport Land Use Compatibility Plan; Volume I”, prepared by Mead & Hunt, October 14,
2004.
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implementation of the General Plan Update will have a less than significant impact within the
vicinity of this public use airport.
Impacts to Emergency Response and Evacuation Plans
The City currently contracts with Riverside County Fire Department for emergency services, and
the City’s Emergency Services Division is responsible for preparing the community for natural
and man made disasters and emergencies. The General Plan Update will facilitate new
development, and therefore will increase population throughout the Planning Area. This increase
in population has the potential to affect emergency response plans and emergency evacuation
plans. Additional emergency services, including new police and fire services, will be required as
development and population increases. In addition, the City’s Emergency Services Division will
need to accommodate the influx of new residents to the area. Impacts to emergency response as a
result of new development and population increases brought on by the General Plan Update will
potentially be significant, unless mitigated. Mitigation measures provided below will reduce
impacts to less than significant levels.
The City prepared the Emergency Operations Plan to prepare for emergencies, and has instituted
the Code RED notification system to help notify the public, through telephone calls, about
emergencies such as water contamination, evacuation notices, wildfires, bomb threats, hazardous
spills, and other emergency situation. The City is also involved in the Community Emergency
Response Team (CERT) program. New residents of La Quinta, as a result of new development
brought on by implementation of the General Plan, may allow for more volunteers for groups
such as CERT. The General Plan Update, therefore, is expected to have a less than significant
effect with an adopted emergency response plans or emergency evacuation plans.
Wildfire Hazard Impacts
The La Quinta Planning Area is situated in a Valley, along the base of the Santa Rosa and San
Jacinto Mountains. Much of the western portion of the Planning Area, particularly within the
City, such as the Cove, is located near the urban-wildland interface. The wilderness areas that
surround La Quinta, as well as other areas along the base of the Santa Rosa and San Jacinto, are
made up of Granitic rock and sparse desert vegetation. The sparse desert vegetation along these
mountainsides does not provide the explosive fuels needed for wildfires. Wildfire risk within the
General Plan Update Planning Area, therefore, is less than significant.
3. Mitigation Measures
The General Plan Update provides policies and programs to reduce the severity of hazards and
lower risks involved with accidental release of hazardous materials or other emergencies. The
following mitigation measures will also help promote a safe environment for existing and future
residents, and ensure impacts will be less than significant.
1. The City will ensure that new generators of hazardous materials will comply with all local,
state, and federal regulations, as required by law.
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2. The City will work with Riverside County Fire, Caltrans, CHP, and other local, state, or
federal agencies to regulate the transport or hazardous materials along local roadways, state
highways, and railways that run through the City or in the vicinity.
3. The City shall incorporate and abide by the policies and regulations highlighted in the
Jacqueline Cochran Regional Airport Master Plan and the Riverside County Airport
Compatibility Land Use Plans for all new development within the Compatibility Land Use
Zones of the Jacqueline Cochran Regional Airport and the Bermuda Dunes Airport.
4. The City shall update the Emergency Operations Plan as necessary to address and plan for
synchronized response to potential emergencies including release or spills of hazardous
materials.
Mitigation Monitoring and Reporting
A. Development plans and permits for uses that use, transport, and/or store hazardous materials
shall be submitted, reviewed, and regulated by proper agencies.
Responsible Parties: Riverside County Fire Department, Riverside County Department of
Environmental Health, City of La Quinta Planning Division, California Certified Unified
Program Agencies, CHP, Caltrans
Hydrology H.
Introduction
This section discusses the hydrological resources in La Quinta, and assesses impacts on these
resources from future growth and development brought on by the General Plan Update. It also
provides mitigation measures to reduce potential impacts to hydrology. The following section
describes the existing hydrological conditions, evaluates potential impacts to hydrological
resources from implementation of the proposed General Plan and sets forth mitigation to reduce
impacts to levels below significance.
It should be noted that Section P: Water Resources and Quality further addresses water quality.
Thresholds of Significance/Criteria For Determining Significance
The following standards and criteria have been drawn from Appendix G: Environmental
Checklist Form of the CEQA Guidelines. To ensure that the General Plan EIR adequately
addresses potential impacts associated with hydrology as a result from the adoption and
implementation development of the La Quinta General Plan, the following factors have been
considered. Implementation of the General Plan would have a significant effect on hydrology if
it is determined that the project will:
a.) Violate any water quality standards or wastewater discharge requirements.
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b.) Substantially alter the existing drainage pattern of the site or area, including through the
alteration of the course of a stream or river, in a manner which would result in flooding
on- or off-site.
c.) Substantially alter the existing drainage pattern of the site or area, including through the
alteration of the course of a stream or river, or substantially increase the rate of surface
runoff in a manner, which would result in flooding on- or off-site.
d.) Create or contribute runoff water, which would exceed the capacity of existing or planned
stormwater drainage systems or provide substantial additional sources of polluted runoff.
e.) Place housing within a 100-year flood hazard area as mapped on a federal Flood Hazards
Boundary or Flood Insurance Rate Map or other flood hazard delineation map.
f.) Place within a 100-year flood hazard area structures, which would impede or redirect
flood flow.
g.) Expose people or structures to a significant risk of loss, injury or death involving
flooding, including flooding as a result of a levee or dam.
h.) Inundation by seiche, tsunami, or mudflow.
1. Existing Conditions
The distribution and circulation of water in a given area is referred to as hydrology. Within this
EIR, hydrology is associated with the management of floodwaters and surface runoff, which are
significantly influenced by the geography and climate of a particular locale. The local
microclimate also affects the amount and intensity of precipitation and therefore plays an
important role in local hydrology. Hydrological conditions in the Planning Area been analyzed in
the Technical Background Study prepared for the General Plan, which is summarized herein.47
The Coachella Valley, including the Planning Area, is situated at the western end of a tectonic
depression, known as the Salton Trough, which extends from Baja California to the Salton Sea at
the eastern end of the Coachella Valley. In the Planning Area, the Valley floor encompasses a
broad, gently sloping basin. This basin forms where canyons of the Santa Rosa Mountains
emerge onto alluvial vans, the Whitewater River floodplain, and sediments of prehistoric lakes.
The foothills of the Santa Rosa Mountains rise in and adjacent to the western portion of the
Planning Area. Most development, including that along the base of the Santa Rosa Mountains in
the western portion of the City, occurs on the Valley floor.
The Planning Area and the region generally enjoy a temperate climate characterized by mild
winters and warm, dry summers. However, regional conditions are influenced by proximity to
the San Bernardino, San Jacinto, and Santa Rosa Mountain ranges and associated climatic zones.
47 “Technical Background Report to the Safety Element Update, City of La Quinta, California,” prepared by Earth
Consultants International, July 2010.
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Flooding can occur as a result of rapid melting of mountain snowpack. Occasional intense
thunderstorms can also cause flooding. Storms occur most frequently during the winter months,
between November and April, although the area also experiences monsoon storms during the
summer and early fall (July through September). While generally of short duration, these storms
may generate several inches of rainfall in localized areas.
Rainfall in the region varies widely. In the surrounding mountains, average rainfall is
approximately 25 inches annually, whereas on the Valley floor, including the Planning Area, it
averages 3 inches. Even in the absence of rain in the Valley itself, flooding can occur when
runoff and associated mud and debris flows from mountain slopes. When precipitation occurs
rapidly, dry soils quickly become saturated and cannot sufficiently percolate the increased
runoff.
Hydrological Conditions and Flood Hazards
Floodplains are meant to carry excess waters during flooding, which is a recurring, natural event.
Flooding becomes a hazard when human uses encroach into floodplains. This encroachment
occurs frequently since floodplains are optimal for agriculture, access to water supplies and
transportation routes. Flooding is among the most destructive and costly of all natural disasters
on a global level and causes more deaths per year than any other geologic hazard. Dollar-based
economic losses as a result of ever-expanding development on floodplains has steadily increased
over the last several decades.
It is difficult to predict rainfall in the region, since it varies widely from year to year. A review of
annual rainfall totals and peak streamflow gages on the Whitewater River demonstrates this
inconsistency. Although in most years, stream discharges have remained at at or near zero cubic
feet per second (cfs), by contrast, peak flows exceeded 10,000 cfs on November 22, 1965 and
January 25, 1969. There is potential for substantial damage when floodwaters reach such high
velocities.
In the planning area, flooding primarily occurs under two scenarios: 1) flash flooding along
natural or man-made channels and 2) sheet flooding across the Valley floor. Brief but powerful
storms can cause high peak volumes and velocities, which are often intensified by local
conditions including both the built environment as well as naturally occurring landforms and
geology. In La Quinta, mountain slopes comprised of impervious rock impede percolation.
Water quickly collects and flows into channels on the Valley floor, often transporting with it
large amounts of mud, sand, rock fragments and other debris.
Flows may exceed the existing natural or man-made channel capacities, or channels are impacted
by debris or structures. Water overflows channel banks, creating the condition known as sheet
flow or sheet flooding.
Increasing urban development results in an increase in impervious surfaces such as buildings,
sidewalks, parking lots, and roadways that reduce the area available for natural percolation.
Downstream areas are then subject to water that formerly would have been absorbed. Unless
new development provides storm drain systems to carry increased flows, downstream flooding
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risks may increase. In the La Quinta Planning Area, these risks are especially prevalent for
development downstream of canyons and the base of mountains, since surrounding mountain
slopes generally receive greater levels of rainfall.
Regional Stormwater Management
Analysis and design of regional flood control structures is the responsibility of the Coachella
Valley Water District (CVWD). In the Planning Area, CVWD manages regional facilities, which
collect runoff from areas outside the City, including surrounding mountains. Planning,
maintenance and construction of improvements for regional facilities fall within the broad
management responsibilities with which CVWD is charged. Of primary concern to CVWD are
rivers, major streams and tributaries, as well as areas of substantial sheet flow. Regional
facilities in the Planning Area include the Coachella Valley Stormwater Channel, Whitewater
River Stormwater Channel, the La Quinta Evacuation Channel, the Bear Creek System, the East
La Quinta Channel System, Dike No. 2, Guadalupe Dike, and Dike No. 4. These are further
described below.
Local Drainage Management
The City of La Quinta is responsible for local facilities, which collect and convey runoff from
local streets and properties to regional channels and basins. The recently updated City Master
Drainage Plan (2009) describes these local facilities. The City has not formally adopted the Plan,
but uses it to manage and document the location and condition of existing stormwater
management facilities. It has also been used to obtain FEMA Letters of Map Revision for some
flood areas.
Major Regional and Local Flood Control Facilities
Major flood control facilities in the planning area are described below and are mapped on
Exhibit III-10, FEMA Flood Zones and Flood Control Facilities.
Whitewater River/Coachella Valley Stormwater Channel
The Whitewater River, which flows into the Coachella Valley Stormwater Channel in the
Planning Area, is the principal drainage course in the City, extending through the Coachella
Valley for 50 miles, with an average cross section of 350 feet. The Channel is generally dry but
may be inundated during storm events. Most of the Coachella Valley Stormwater Channel
sections within the City have reinforced slope protection; the remaining portions are protected by
unreinforced earthen berms. Although the Channel generally follows the recent historical natural
river path, it deviates from this course where it passes through the City between Jefferson Street
and Miles Avenue. The Federal Emergency Management Agency (FEMA) has indicated the
potential for breakout of the levee system along this reach of the river in the event of a 100-year
storm. This is further discussed under Seismically Induced Flooding, below.
The aforementioned reinforced slopes and remaining unreinforced earthen banks are classified
by FEMA as “Provisionally Accredited Levees,” indicating that they provide protection from the
100-year flood. CVWD has recently (2009) submitted required documentation to FEMA
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demonstrating the protection capabilities of these levees in compliance with requirements of
Section 65.10 of National Flood Insurance Program (NFIP) regulations (Title 44, Chapter 1 of
the Code of Federal Regulations).
Bear Creek System
Runoff from the Santa Rosa Mountains to the west/southwest flows into the Upper Bear Creek
System, which is located along the southerly and westerly margins of the Cove. The system
includes the Upper Bear Creek Training Dike, Upper Bear Creek Detention Basin, Bear Creek,
as well as Bear Creek Channel and four associated side inlet channels and a downstream drop
structure. The dike diverts runoff from a 1.7 square mile drainage area, then directs it along Bear
Creek to the detention basin, which has a storage capacity of 752 acre-feet. Bear Creek Channel
receives outflows from the Basin. The Channel is approximately 2.5 miles long. It is a soil-
cement lined trapezoidal channel with 100-year flood flow capacity, with four inlet channels on
the western side that drain smaller canyons. From the Channel, flows continue into the Oleander
Reservoir downstream, thence into the La Quinta Evacuation Channel, and ultimately discharge
into the Coachella Valley Stormwater Channel. CVWD has applied for FEMA accreditation of
the Bear Creek Channel System, including the training dike, and is awaiting receipt of the formal
accreditation letter.
Oleander Reservoir
The Oleander Reservoir detention basin is located in the La Quinta Resort and Club Mountain
golf course. In collects runoff from the Bear Creek system as well as flows from drainage areas
north and west of it. Flows then discharge into the La Quinta Evacuation Channel. The Standard
Project Flood elevation is projected to be 54 feet at the reservoir.
La Quinta Resort Channel
The La Quinta Resort Channel is a man-made channel generally located along the western
boundary of the City northwest of the Cove. Runoff from mountains west of this area is collected
along this Channel and conveyed to the Oleander Reservoir.
East La Quinta System
The East La Quinta System is located along the southeastern edge of the Cove area, comprised of
the riprap lined, trapezoidal East La Quinta Channel and several detention basins. It collects
drainage from hills east and south of Calles Bermudas as well as outflows from the Calle
Tecolate Detention Basin located at the southwestern point of the Cove. The system channels
flows to the Avenida Bermudas Detention Basin, which manages runoff and debris from
surrounding drainage areas via a 60-inch reinforced concrete buried storm drain with 100-year
stormwater flows capacity. Flows from the basin are conveyed to the La Quinta Evacuation
Channel.
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La Quinta Evacuation Channel
The La Quinta Evacuation Channel flows northeasterly from the Bear Creek Channel,
approximately 3.5 miles through developed areas of the City to the Coachella Valley Stormwater
Channel. This Channel is designed to capture and carry stormwater from various flood control
systems in the City. There are two reaches, of which the lower is approximately 2.4 miles long
within a 50-foot wide trapezoidal earthen channel. The upper reach is a grass-lined, irregularly
shaped channel approximately 1.1 miles long.
La Quinta North Diversion Channel
This facility is described in the City Master Drainage Plan as conveying “the [Standard Project
Flood] SPF from off-site mountain areas northwest of the City . . . southerly to the Oleander
Reservoir.” It is unclear whether this is an additional facility or another name for the La Quinta
Resort Channel.
Lake Cahuilla
Lake Cahuilla, while not a flood control facility, constitutes a major regional facility managed by
CVWD and is therefore considered herein as part of the evaluation of flooding hazards. Lake
Cahuilla was constructed in 1969 as a reserve storage facility for irrigation water. The lake is
located on approximately 135 acres at the base of the foothills of the Santa Rosa Mountains,
between Avenues 56 and 58, west of Jefferson Street. It terminates the Coachella Branch of the
All-American irrigation canal. The Lake Cahuilla County Park, operated by Riverside County
Parks and Open Space District, is located at the same site on lands leased by CVWD to the Parks
District.
Lake Cahuilla has a capacity of approximately 1,500 acre-feet of water at depths of 11 to 12 feet,
protected by a levee system approximately 25 feet high and 100 feet wide. It is cement lined and
sealed with a six-inch layer of soil cement. Lake Cahuilla contains more than 50-acre feet of
storage capacity. Normally a facility with this capacity would fall under the purview of the
Division of Dam Safety. However, since Lake Cahuilla is not impounded by an artificial barrier
(dam), the Division does not oversee it. Nonetheless, the structural integrity of levees protecting
the lake have potential to be compromised in a severe earthquake and should therefore be
monitored routinely. This is further discussed under Seismically Induced Flooding, below.
Local Structures
Within the Planning Area there are a variety of local structures, including storm drains, culverts
and catch basins located within private development and area streets. These facilities collect and
retain stormwater and irrigation runoff, and in some cases, detain flows for eventual evaporation
or infiltration. The City requires that new developments retain project-related stormwater runoff
produced over the peak twenty-four-hour period of a 100-year storm, unless requirements are
waived by the City Engineer.
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Dikes
There are several dikes located near the base of mountains in the Planning Area, which have
been constructed to protect agricultural lands on the Valley floor from runoff from mountain
slopes. In addition to the Bear Creek Training Dike, previously discussed, these include two
dikes constructed by the Bureau of Reclamation: Dike 2 and Dike 4, which were constructed to
protect Lake Cahuilla as well as lands between Avenue 58 and Avenue 66. Dike 2 and Dike 4
total 5.2 miles, and are located south and southeast of Lake Cahuilla, respectively. Dike 4
encompasses the Guadalupe Dike and Guadalupe Training Dike. Dike 4 is accredited by FEMA;
Dike 2 is not yet accredited.
CVWD has constructed approximately 165 acres of groundwater recharge basins within the Dike
4 impound area. These basins comprise an important component of groundwater replenishment
programs discussed in CVWD’s Urban Water Management Plan for recharge of the groundwater
basin in the eastern Coachella Valley. These facilities are also discussed in Section III-P, Water
Resources/Quality.
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National Flood Insurance Program
The Federal Emergency Management Agency (FEMA) evaluates flood hazards. As mandated by
the National Flood Insurance Act of 1968 and the Flood Disaster Protection Act of 1973, FEMA
administers the National Flood Insurance Program (NFIP) to provide subsidized federal flood
insurance to residents of communities where future floodplain development is regulated. FEMA
has developed Flood Insurance Rate Maps (FIRMs) for many areas in the United States so as to
determine the need for and availability of federal flood insurance. FIRMs assist the federal
government in establishing appropriate flood insurance premiums as well as determining
elevations and flood proofing measures. Through the National Flood Insurance Reform Act
(1994) established grant programs for flood mitigation to states and local communities. The
Community Rating System (CRS) was instituted through the 1994 legislation, and implements a
system by which communities that manage and protect natural floodplain functions and erosion
hazards are credited.
The City of La Quinta has held NFIP membership since 1985. Most recent La Quinta FIRM
maps were updated in 2008 and include 12 community panels. Riverside County has
participated in the NFIP since 1980. Property owners within the Planning Area are therefore
eligible for flood insurance, and must purchase insurance prior to obtaining financing to buy,
build or improve structures in a Special Flood Hazard Zone based on FEMA mapping.
FIRM maps include a variety of flood risk information based on historic, meteorological,
hydrologic and hydraulic data, as well as existing development, open space and topographic
conditions within an area. They also incorporate the results of engineering studies conducted by
FEMA, which establish the “base flood” (100-year flood). Areas subject to the 100-year flood
are considered at high risk of inundation. FEMA uses these data to delineate Special Flood
Hazards Zones.
FIRM maps are subject to updates as local conditions, including development, hydrologic
conditions, populations, and other variables may change frequently. All areas of flooding are not
necessarily identified on these maps. FEMA has instituted a Map Modernization Program to
improve the accuracy of FIRM maps. It has set a goal of creating digital maps to delineate 65%
of the continental U.S. and 92% of the population.
Flood Hazard Zones in the Planning Area
Flood Hazard Zone data from corresponding FIRM Community Panels (maps) for the La Quinta
planning area is described below and shown on Exhibit III-10, FEMA Flood Zones and Flood
Control Facilities. As noted above, FIRMs for La Quinta were published in 2008. There have
been two floodplain map revisions for the Planning Area approved by FEMA. As a result, all
developed areas in the City’s corporate limits are outside the 100-year flood zone and do not
require flood insurance.
Zone A: Areas of 100-year flood where no base flood elevations or depths are shown.
Requires flood insurance.
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Zone AO: Areas of 100-year flood with average depths of 1 – 3 feet, generally from sheet
flow on sloping terrain. Requires flood insurance.
Zone X: Areas of 500-year flood with average depth of less than 1 foot or less than one
square mile drainage area; and protected by levees from 100-year flood. No base flood
elevations or depths are shown. Flood insurance available but not required.
Zone D: Areas where flood hazards are undetermined but flooding is possible. Flood
insurance available but not required.
As shown on Exhibit III-10, Zones A or AO in the Planning Area (areas within the 100-year
flood plain) occur within the Coachella Valley Stormwater Channel, the La Quinta Evacuation
Channel, Bear Creek Channel, and detention basins.
Areas within Zone X include portions of the area north and south of the Coachella Valley
Stormwater Channel, the entire Cove area, several areas south and southeast of Lake Cahuilla,
and a portion of the City’s eastern Sphere of Influence.
All-Weather Crossings
There are two primary crossings over the Whitewater River in La Quinta. These are at
Washington Street and Jefferson Street, and provide all-weather access. Other all-weather
crossings include those at Eisenhower Drive and Washington Street at the La Quinta Evacuation
Channel. The City regularly inspects these crossings for scour damage during and after flooding.
The Coachella Branch of the All-American Canal extends through the City and is used for
irrigation purposes, and does not serve as a flood control facility. Canal crossings occur at
Avenue 50 and Avenue 52. Flows through the canal are managed by CVWD, and these
crossings are expected to remain passable during storm events. Nonetheless, periodic inspections
are needed to ensure the safety and reliability of these crossings.
Bridge Scour
Erosion in or along a streambed can damage bridge foundation supports, including piers and
abutments. Scour can occur when upstream flows are forced downstream, eroding the streambed
adjacent to bridge piers, when directional changes in flow result in erosion adjacent to
abutments, or when flows are forced through a narrow opening, increasing velocities and causing
erosion. This phenomenon can occur along highway or railroad bridges, and may take place
either on the floodplain, in the main channel, or in both areas. Scour has resulted in substantial
damage and even collapse of bridges elsewhere in the U.S. The State of California has
implemented a seismic retrofit program that includes inspection of bridge underpinnings. This
program is expected to help reduce potential impacts from scour to bridge foundations.
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Seismically Induced Inundation
Strong ground shaking or other effects resulting from earthquakes can undermine water retention
and storage structures, such as dams, levees, and above-ground water tanks. Resulting flooding
can inundate downslope or adjacent areas. The following describes conditions in the Planning
Area relative to this risk.
Dam Failure
The California Division of Dam Safety is charged with ensuring the structural reliability of large
capacity dams in the state. California State Water Code, Division 3, contains statutes governing
the safety of dams. The Division monitors structural safety of dams higher than 25 feet or with
more than 50 acre-feet of storage capacity. Data from the California Office of Emergency
Services indicates that there are no potential inundation risks from existing dams to the Planning
Area. As previously discussed, although Lake Cahuilla has a storage capacity of more than 50-
acre feet, it does not fall under the jurisdiction of the Division since it is not impounded by a
dam.
Levee Failure and Seiching
There are several major stormwater or irrigation facilities in the Planning Area, including the
Coachella Valley Stormwater Channel, the Coachella Canal and Lake Cahuilla. Levee systems
can be damaged or fail as a result of lateral spreading, which can occur as a result of strong
ground shaking. Lateral spreading is the lateral movement of underlying soils either which have
become liquefied or fractured. Levee damage has occurred in the Imperial Valley and other areas
as a result of liquefaction and lateral spreading. Although the potential inundation area of the
canal or Lake Cahuilla has not been demonstrated through engineering analyses, should either
fail completely, development directly downstream would be impacted.
Unreinforced banks along the Coachella Valley Stormwater Channel in the Planning area are
subject to damage from erosion and strong ground shaking associated with earthquakes. CVWD
periodically maintains these levees. Where the Channel passes through the City between
Jefferson Street and Miles Avenue, it diverges from the natural watercourse. FEMA flood
insurance studies (2008) indicate the potential for a “breakout” along this reach of the river
during a 100-year storm. In the event of such a breakout, a 50% loss of channel capacity could
occur, as well as flooding within a portion of the City’s northeast Sphere-of-Influence and in the
cities of Coachella and Indio.
Open bodies of water, such as canals, above-ground storage tanks, detention basins and
swimming pools are subject to seiching, or water sloshing, during strong ground shaking from
earthquakes. In the Planning Area, the water bodies listed above as well as Lake Cahuilla may be
subject to seiching during earthquakes. Downslope development may be inundated when water
overtops or damages containment structures as a result of seiching. The following further
describes risks associated with inundation from above-ground storage tanks, of which there are
several in the Planning Area.
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Inundation from Above-Ground Storage Tanks
Strong ground shaking can cause structural damage to above-ground water storage tanks,
especially when they are not adequately braced and baffled. Tanks can be lifted off of
foundations by the movement of sloshing water, damaging the shell and roof and causing the
bottom to bulge. Water may also be released when pipes leading to the tank are sheared off. In
California and Mexico, the Landers and Big Bear earthquakes in 1992, the Northridge (1994),
and the Sierra El Mayor-Cucupah in 2010 all resulted in damage to water tanks, with inundation
of homes down gradient also occurring in some cases. As a result of the 1992 and 1994
earthquakes, design standards for steel water tanks were revised. New tank design calls for
flexible joints at connection points so that movement can occur in all directions.
In addition to inundation of structures down slope, potable water supplies may be reduced,
impacting availability of drinking water as well as fire flows and other emergency services
needs. Water supplies may be impacted for 30 days or longer should damage occur to other
critical facilities, such as aqueducts that carry imported water throughout southern California,
wells, pipelines and other facilities associated with the domestic water system in the region and
Planning Area. This emphasizes the need to inspect and retrofit tanks to make certain their
structural reliability in the event of an earthquake, as well as to ensure that water supplies in
reservoirs are kept at or near capacity.
CVWD has ten water reservoirs in the Planning Area, with a total capacity of 44.6 million
gallons. These are of welded steel, constructed current seismic and American Water Works
Association standards. The oldest was constructed in 1982 and the most recent in 2008. Many
although not all of these are situated in elevated locations upslope of existing development.
Federal and State Regulatory Requirements
Federal Clean Water Act
The Clean Water Act (CWA) was enacted in 1972, and was intended to set goals for restoring
and maintaining water quality through reduction of point source pollution by industry and
sewage treatment facilities. Waterbodies containing “waters of the U.S.” fall under the
jurisdiction by the U.S. Army Corps of Engineers, which administers Section 404 of the CWA
for these waters. In the Planning Area, development projects proposing construction activities
within the Coachella Valley Stormwater Channel are subject to compliance with Section 404
regulations and may be required to obtain a 404 permit. Such projects may also be subject to
compliance with Section 401 of the CWA, which is administered in the Planning Area by the
State Regional Water Quality Control Board (RWQCB), Colorado River Basin Region. These
issues are further discussed in Section III-D, Biological Resources.
National Pollutant Discharge Elimination System (NPDES)
In 1987 the CWA was amended to require states to reduce runoff into waterways. These
requirements are implemented by the National Pollutant Discharge Elimination System (NPDES)
program. NPDES mandates the adoption of stormwater management plans and programs to
reduce runoff of pollutants in storm water systems into waters of the United States.
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The RWQCB implements the NPDES on a statewide basis. The Board issues NPDES permits to
local jurisdictions., which are held as joint permits among multiple jurisdictions in some regions,
including Riverside County. The NPDES program in which La Quinta participates also includes
Riverside County Flood Control & Water Conservation District, CVWD, Riverside County, and
all Riverside County cities except for Blythe.
California Fish and Game Code
When surface disturbance and/or land development has potential to alter the bed and banks of
streambed areas in the Planning Area, a site-specific Streambed Alteration Agreement (SAA)
may be required, pursuant to Section 1602 of the California Fish and Game code. This is also
further discussed in Section III-D, Biological Resources.
2. Project Impacts
Implementation of the proposed General Plan will facilitate urban development that will result in
an increase in impervious surfaces, such as roadways, sidewalks, and parking lots. Water that
would have been re-absorbed into the ground will runoff to downstream areas. The City and
CVWD have worked pro-actively to protect developed areas in the City from flood hazards.
Currently, with the exception of some golf courses that serve dual purpose as stormwater
retention areas, no developed areas in the City are within a FEMA Special Flood Hazard Zone.
Therefore, property owners in the City are not required to purchase flood insurance. However,
localized flooding can still occur in some areas, primarily where storm drains are not adequately
sized or temporary retention facilities are not present. Further, it is difficult to predict conditions
that may create localized flooding. This may occur when storm flows carrying debris clog catch
basins or inlets, or in the event that levees are compromised or overtopped. In such instances,
residents may need to evacuate, and the City should prepare evacuation plans for this potential.
Further, land use planning must consider the location of critical facilities, including schools, or
facilities where hazardous materials may be used, stored or generated on-site.
Substantial areas in the City are zoned by FEMA as having potential to flood during a storm
stronger than the 100-year event, or subject to shallow flooding during a 100-year storm.
Therefore, property owners outside Special Flood Hazard Areas are encouraged by FEMA to
purchase flood insurance. It should also be noted that flood zone mapping within areas subject to
moderate flood hazard is incomplete.
Given that the region is seismically active, the Planning Area may be susceptible to flooding if
water reservoirs or water retention structures or facilities should fail. The Planning area is not
located downstream of any State-regulated dam, or within a dam inundation area as identified by
the Division of Dam Safety. The City and Sphere are traversed by the Coachella Valley
Stormwater Channel, which is protected in many areas by a system of sand levees. These have
potential for seismic settlement or liquefaction, especially in the event of strong ground shaking
or long periods of rain. Earthquakes can also create seiche conditions within open waterbodies,
such as Lake Cahuilla, canals, reservoirs and catch basins. The sloshing movement of water
within containment structures can damage them, and water may overtop, potentially inundating
areas down slope.
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There is potential for the regional domestic water system to be damaged and potentially unusable
for a period of greater than 30 days in the event of a large-scale earthquake. Therefore, water
storage tanks should be maintained as full as possible, and their integrity ensured through
periodic inspections and repair as needed. Coachella Valley Water District has indicated that the
water storage tanks in the area are built to current seismic standards.
The General Plan includes goals, policies and programs to ensure that future development is
reviewed for potential risk of flood hazards and to require that it include on-site stormwater
retention facilities. It also encourages the retention of natural watercourses wherever feasible,
and/or providing for compatible open space and recreational uses within areas subject to
flooding.
Flood Protection Measures for Property Owners
Future development within the Planning Area may be subject to localized flooding risks,
especially where flood hazard mapping is incomplete. The General Plan includes a range of
policies intended to reduce these risks, including enforcement of existing County and City
ordinances that address hazards and floodplain regulations; updating hazards mapping regularly;
and public education about flood hazards. Project developers and property owners are
encouraged to implement site design and other means to avoid or reduce risks to personal
property, including structures. These are further addressed under Mitigation, below.
3. Mitigation Measures
1. The City shall continue to encourage project developers to use engineering and design
techniques that minimize the potential for the occurrence of inundation, including seismically
induced inundation.
2. The City shall continue to coordinate with the Coachella Valley Water District to monitor the
structural safety of the levees around Lake Cahuilla and along the Coachella Valley
Stormwater Channel within the City.
3. The City shall continue to coordinate with the Coachella Valley Water District to monitor the
structural integrity of above-ground water tanks and reservoirs, and where needed, to
implement bracing techniques to minimize potential structural damage and/or failure.
4. The City shall coordinate and cooperate with the Coachella Valley Water District in the filing
of FEMA applications to amend the Flood Insurance Rate Maps, as necessary.
5. The City shall continue to coordinate with CVWD to assure the adequate inspection of bridge
crossings for scour damage during and after significant flooding events, and shall coordinate
with the appropriate state agencies to participate in the state’s bridge scour inventory and
evaluation program.
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6. New development shall continue to be required to construct on-site retention/detention basins
and other necessary stormwater management facilities that are capable of managing 100-year
stormwater flows.
7. New development immediately adjacent to regional flood control facilities shall continue to
have the option of discharging 100-year stormwater flows directly into the stormwater
channel, subject to approval by the appropriate agencies.
8. The City shall refer developers of new projects within areas historically used for agriculture
to the Coachella Valley Water District to identify the location of subsurface agricultural
drains.
9. The City shall routinely update its Emergency Operations Plan to address flooding hazards
within the City.
Mitigation Monitoring and Reporting
A. The City Engineer shall report to the City Council on a regular basis to ensure that local
drainage plans are updated and drainage control projects are implemented. Reports shall
include information regarding the status of regional drainage facilities affecting flood control
in the City.
Responsible Parties: City Engineer, City Council, Coachella Valley Water District
B. Prior to issuance of building permits, the City shall review and approve project-specific
hydrology and hydraulic studies, Water Quality Management Plans and mitigation plans for
development proposals, and shall ensure they are adequate with regard to stormwater
management, on-site retention, best management practices and pollution control.
Responsible Parties: City Engineer, Project Developer
Land Use and Planning I.
Introduction and Background
This section of the EIR addresses potential impacts and opportunities associated with land use
and planning from implementation of the La Quinta General Plan. The existing conditions,
development and land use designations within the City and Sphere of Influence are described,
and the potential impacts relating to changes in the land use from the previously approved
General Plan are assessed.
Thresholds of Significance/Criteria for Determining Significance
The following thresholds or criteria are derived from Appendix G of the CEQA Guidelines, and
are used to determine the level of potential effect. The significant criteria are at least in part
based on the recommendations set forth in Section 15064 of the CEQA Guidelines. For analysis
purposes build out of the La Quinta General Plan would have a significant effect on land use and
planning if it is determined that the project will:
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a) Physically divide an established community;
b) Conflict with any applicable land use plan, policy, or regulation of an agency with
jurisdiction over the project (including, but not limited to the general plan, specific
plan, local coastal program, or zoning ordinance) adopted for the purpose of avoiding
or mitigating an environmental effect; or
c) Conflict with any applicable habitat conservation plan or natural community
conservation plan.
1. Existing Conditions
The City of La Quinta was first established as a rural and predominantly agricultural community.
Today, the City of La Quinta consists of an urban core with residential, resort, and commercial
development surrounded by hillside open space that offers recreational opportunities and land
preservation. Lands within city limits have mostly been developed with a few undeveloped infill
lots located throughout the urban area. The Sphere of Influence, east of the city limits contains
undeveloped lands that represent the greatest growth and land conversion potential.
The existing land uses in the Planning Area are governed by the 2002 Comprehensive General
Plan, which includes La Quinta City limits, as currently amended, two Sphere of Influence areas,
one north and one east of the City limits, and two Planning Areas, both of which are east of the
City limits beyond the Sphere of Influence. Planning Area 1 is west of Jackson Street and
Planning area 2 is to the east.
Surrounding Land Use
The City of La Quinta is located in the central portion of the Coachella Valley within the
southern region of Riverside County. The Coachella Valley contains several cities and a few
unincorporated communities of Riverside County. The Coachella Valley is located in between
the Santa Rosa and San Jacinto Mountain Ranges on the west and the Little San Bernardino
Mountains on the East.
There are a number of jurisdictions surrounding the City of La Quinta including Palm Desert,
Indian Wells, Bermuda Dunes, Indio. North of La Quinta are the cities of Indio and Coachella,
and Riverside County. The cities of Rancho Mirage, Cathedral City and Palm Springs are up-
Valley from La Quinta and consist of similar land use designations, while the communities of
Thermal and Mecca are located down-Valley and tend to include land uses associated with
agricultural production and light industry as well as residential land uses. Although the overall
region can be described as rural, with large swaths of open desert, the established communities
within the Coachella Valley constitute an urbanized area that include a range of residential,
commercial, industrial, public facilities and open space land uses. Lands immediately east of the
City are within unincorporated Riverside County and include the City’s Sphere of Influence and
Planning Areas 1 and 2. For the most part, these lands are largely vacant, undeveloped and
sparsely populated.
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Land uses east and south of the City Boundary and Planning Areas are designated for
agricultural purposes, residential uses, and open space and are within Riverside County. These
include Native American Tribal lands.
Lands to the west and south of the City Boundary are also within unincorporated Riverside
County and include mountain slopes of the Santa Rosa Mountains that are designated for open
space preservation as public lands.
Existing City Limits Land Use
Residential development in the City of La Quinta is consistent with residential development
patterns observed throughout the Coachella Valley. La Quinta consists primarily of low density
and resort residential development with scattered medium and high-density development
occurring in certain areas of the City. Residential development represents approximately 40% of
the City land uses with low density residential accounting for 76%, medium density 17% and
high density residential making up only 1% of the total designated land use for residential. Low-
density residential land uses range from 0 to 4 dwelling unit per gross acre. Medium and high-
density land uses range from 0 to 20 dwelling units per gross acre.
Commercial land uses are established throughout the City and account for approximately 6% of
the designated land uses. Commercial land uses generally occur at the intersection of two major
travel corridors. Highway 111, which transects the northern portion of the City, represents a
dense commercial corridor. The community center contains an established Village Commercial
area, which is located just north of the Cove neighborhood. The Tourist Commercial land use
designation serves to provide retail services in conjunction with the major tourist attractions such
as golf, dining, and resort facilities.
The City’s Open Space land use designation largely consists of golf course development in the
urban core and land use preservation in the surrounding hillsides. The City has integrated public
and private open space areas, including parks and recreational facilities. Recreational open
spaces include golf courses, open space associated with the Whitewater River and the La Quinta
Channel, and recreational trails and opportunities associated with the Santa Rosa and San Jacinto
Mountains.
The Whitewater River, an ephemeral stream that serves as the primary drainage corridor for the
Coachella Valley, runs generally west to east through the northern portion of the City. The La
Quinta Channel is another major drainage feature that conveys runoff flows from the mountains
surrounding the cove area from the southwest portion of the City diagonally through the central
portion of the City in an easterly direction, where it connect with the Whitewater River in the
northeast portion of the City. Various golf courses are developed in conjunction with these
ephemeral waterways.
Institutional development and public facilities, such as schools, libraries, fire and police stations
are characterized as major community facilities and are located throughout the City of La Quinta.
The City’s Civic Center complex is centrally located on Calle Tampico and contains government
and community facilities, the senior center, a library, and park land. The Civic Center and
associated facilities are situated in close proximity to the downtown Village Commercial area.
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Table III-16
Existing Land Use Designations within City Limits
2002 General Plan Designations Developed Undeveloped Total
VLDR Very Low Density up to 2 du/ac 261 198.2 459.2
LDR Low Density up to 4 du/ac 3,202.5 3,096.9 6,299.4
MDR Medium Density up to 8 du/ac 1,063.9 324.2 1,388.1
MHDR Medium-High Density up to 12 du/ac 14.5 69 83.4
HDR High Density up to 16 du/ac 0.6 86.7 87.3
Total Residential Acreage 4,542.4 3,775.0 8,317.5
M/RC Mixed Commercial 87.9 309 397
CC Community Commercial 24.2 93.7 117.9
NC Neighborhood Commercial 61.8 50.8 112.5
CP Commercial Park 0.0 64 64
O Office 0.0 39.9 39.9
TC Tourist Commercial 206.2 145.3 351.5
VC Village Commercial 64.4 68.8 133.2
Total Commercial Acreage 444.5 771.5 1,216.0
I Industrial 0.0 0.0 0.0
MC Major Community Facilities 178.3 13.1 191.3
P Park Facilities 601.3 128 729.3
OS Open Space 1,246.2 4,258.7 5,505.00
G Golf Course Open Space 3,125.3 986.7 4,111.90
W Watercourse/Flood Control 468.9 132.8 601.7
Total Other Acreage 5,619.90 5,519.3 11,139.2
Total Acreage 10,606.7 10,065.8 20,672.6
The general land use pattern described above reflects 2002 General Plan designations based on
current land use development throughout the City. The existing land uses within the City’s
Sphere of Influence are described below.
Existing Land Uses in the Sphere of Influence
The City of La Quinta has included adjacent lands to the north and east of the existing City
boundary as part of the Sphere of Influence. North and east of the existing City boundary are
small areas within the Sphere of Influence that currently contain vacant lands and limited
existing residential development, all land uses in these areas are currently designated as low
density residential. The larger Sphere of Influence located south of Avenue 52 also consists of
vacant parcels and limited residential development, and is designated as low density residential
with scattered medium density residential, open space golf course development, and a small area
designated for commercial land use.
The City has studied the land use pattern in the Sphere, and has considered several potential
annexation proposals in the past. These proposals included analyses relating to the availability
and cost of the provision of services in the Sphere. These analyses found that in the eastern
Sphere in particular, lands have been encumbered by the County as collateral for a regional bond
issue. As a result, there will be no property tax generation to the City from these lands for a
number of years. The fiscal analysis concluded that the annexation of property in the Sphere
Terra Nova/La Quinta General Plan EIR
Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
III-119
would have a negative fiscal impact on the City. At the time of the analysis, a per unit mitigation
fee was considered, but the proposed annexations did not proceed, and the mitigation program
was not implemented. The costs associated with annexation to the City, however, still exists, and
will remain an issue as annexation proposals occur in the future.
Table III-17
2002 Land Use Designations within Sphere of Influence
2002 General Plan Land Use Designations Developed Undeveloped Total
VLDR Very Low Density up to 2 du/ac 0.0 0.0 0.0
LDR Low Density up to 4 du/ac 549.5 286.5 836
MDR Medium Density up to 8 du/ac 171.7 66.2 237.9
MHDR Medium-High Density up to 12 du/ac 0.0 0.0 0.0
HDR High Density up to 16 du/ac 0.0 0.0 0.0
Total Residential Acreage 721.3 352.7 1,073.90
M/RC Mixed Commercial 4.5 0.0 4.5
CC Community Commercial 0.0 0.0 0.0
NC Neighborhood Commercial 0.0 0.0 0.0
CP Commercial Park 0.0 0.0 0.0
O Office 0.0 0.0 0.0
TC Tourist Commercial 0.0 0.0 0.0
VC Village Commercial 0.0 0.0 0.0
Total Commercial Acreage 4.5 0.0 4.5
I Industrial 0.0 0.0 0.0
MC Major Community Facilities 2 0.0 2
P Park Facilities 0.0 0.0 0.0
OS Open Space 0.0 0.0 0.0
G Golf Course Open Space 229.8 88 317.8
W Watercourse/Flood Control 0.0 0.0 0.0
Total Other Acreage 231.8 88 319.8
Total Acreage 957.6 440.7 1,398.3
Total Existing Land Uses in the Planning Areas
In addition to the Sphere of Influence, there are also two separate Planning Areas that were
considered as part of City’s planning efforts under the 2002 General Plan. Planning Area 1 is
located east of Monroe Street and Planning Area 2 is located east of Jackson Street. Planning
Areas 1 and 2, east of the existing city boundary, are currently governed by Riverside County.
The existing land uses in Planning Area 1 are comprised of vacant parcels, agricultural uses, and
very low density residential. Planning Area 2 contains vacant parcels, polo fields, agricultural
uses, and very low-density residential land uses. Lands within Planning Area 1 and 2 are
designated for a variety of land uses including mixed/regional commercial, office, and industrial
land uses. Existing land use designation for Planning Areas 1 and 2 can be seen in the following
Table.
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Table III-18
2002 Land Use Designations within Planning Areas
P1 P2
2002 LU Designations Developed UnDev. Total Developed UnDev Total
VLDR up to 2 du/ac 0.0 0.0 0.0 64.4 0.0 64.4
LDR up to 4 du/ac 2,447.20 551.2 2,998.4 5,213.6 846.8 6,060.3
MDR up to 8 du/ac 58.2 62.7 120.8 358.8 100.5 459.3
MHDR up to 12 du/ac 259.7 78.9 338.6 0.0 0.0 0.0
HDR up to 16 du/ac 0.0 0.0 0.0 93.7 71.4 165.1
Total Residential Acreage 2,765.0 692.7 3,457.8 5,730.4 1,018.70 6,749.1
M/RC Mixed Commercial 0.0 0.0 0.0 69.3 14.3 83.6
CC Community Commercial 7.2 2.9 10 219.7 33.1 252.8
NC Nhhd Commercial 47.2 2.5 49.7 0.0 0.0 0.0
CP Commercial Park 0.0 0.0 0.0 0.0 0.0 0.0
O Office 0.0 0.0 0.0 43.7 0.0 43.7
TC Tourist Commercial 0.0 0.0 0.0 0.0 0.0 0.0
VC Village Commercial 0.0 0.0 0.0 0.0 0.0 0.0
Total Commercial Acreage 54.4 5.3 59.7 332.7 47.3 380.1
I Industrial 0.0 0.0 0.0 319.7 60.6 380.3
MC Facilities 29 0.0 29 0.0 36.7 36.7
P Park Facilities 0.0 0.0 0.0 0.0 0.0 0.0
OS Open Space 0.0 44.5 44.5 496.2 149.4 645.6
G Golf Course OS 198.8 59.8 258.6 0.0 0.0 0.0
W Water/Flood Control 0.0 0.0 0.0 0.0 0.0 0.0
Total Other Acreage 227.8 104.3 332.1 815.9 246.6 1,062.5
Total Acreage 3,047.3 802.3 3,849.5 6,879.0 1,312.70 8,191.7
Summary of Existing Land Uses
The 2002 General Plan contains a total of 34,112 acres within City limits, the Sphere of
Influence and Planning Areas 1 and 2. Land use designations include a variety of residential,
commercial, open space, and public facility development. Overall, approximately 75% of the
designated land uses are developed and 25% remain undeveloped.
The following table shows the developed and undeveloped acreage for each land use type and
the total acreage assigned through the entire Planning Area.
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Table III-19
Existing Land Use Summary
2002 General Plan Land Use Designations Developed Undeveloped Grand Total
VLDR Very Low Density up to 2 du/ac 325.4 198.2 523.6
LDR Low Density up to 4 du/ac 11,412.8 4,781.4 16,194.1
MDR Medium Density up to 8 du/ac 1,652.6 553.6 2,206.10
MHDR Medium-High Density up to 12 du/ac 274.2 147.9 422
HDR High Density up to 16 du/ac 94.3 158.1 252.4
Total Residential Acreage 13,759.1 5,839.1 19,598.2
M/RC Mixed Commercial 161.7 323.3 485
CC Community Commercial 251.1 129.7 380.7
NC Neighborhood Commercial 109.0 53.3 162.2
CP Commercial Park 0.0 64.0 64
O Office 43.7 39.9 83.6
TC Tourist Commercial 206.2 145.3 351.5
VC Village Commercial 64.4 68.8 133.2
Total Commercial Acreage 836.1 824.1 1,660.2
I Industrial 319.7 60.6 380.3
MC Major Community Facilities 209.3 49.8 259
P Park Facilities 601.3 128.0 729.3
OS Open Space 1,742.4 4,452.6 6,195.1
G Golf Course Open Space 3,553.9 1,134.5 4,688.3
W Watercourse/Flood Control 468.9 132.8 601.7
Total Other Acreage 6,895.4 5,958.2 12,853.6
Total Acreage 21,490.6 12,621.5 34,112.0
Regional Land Use Planning
The Coachella Valley Association of Government (CVAG) is the Valley-wide planning authority
and the Southern California Association of Governments (SCAG) is the regional planning
authority for the City of La Quinta. The SCAG Regional Comprehensive Plan48 was adopted in
2008 and proposed policies, goals and programs that are intended to address regional issues such
as transportation, housing, air quality, water resources. Land use planning can be effective in
addressing these concerns by proving continuity and interconnectivity through a region, gaining
efficiencies through mixed use, and preserving open space and water course resources.
2. Project Impacts
Although several land use changes are proposed under the General Plan Update, the Preferred
Alternative does not significantly change the overall development pattern for the La Quinta
Planning Area. Planning Areas outside of City limits have been reduced to the Sphere of
Influence and no longer call out separate Planning Areas 1 and 2, which were part of the 2002
General Plan. Under the proposed General Plan Update similar land use designations have been
consolidated to simplify land use descriptions.
48 “Final 2008 Regional Comprehensive Plan,” prepared by the Southern California Association of Governments,
2008.
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Some land use designations under the 2002 General Plan have been grouped together and
consolidated into a single land use designation under the proposed update. For example, Very
Low and Low Density Residential land use designations have been combined under the Low
Density land use designation as set forth under the proposed land use plan. Similarly, the
Medium Density, Medium-High Density, and High Density Residential land uses under the 2002
General Plan have been consolidated under the new land use designation, Medium/High Density
Residential. Several of the commercial and retail land use designations that were individually
defined under the 2002 General Plan are reclassified into one of the three new commercial land
use designations: General Commercial; Tourist Commercial; and Village Commercial.
Proposed Land Uses within City Limits
The following describes the proposed land use designation set forth under the General Plan
Update for those lands within the City limits of La Quinta. The calculations of dwelling units and
square footage were based on the following assumptions:
For residential development, all lands are assumed to develop at 75% of the maximum
density allowed in that designation.
For commercial and industrial development, all lands are assumed to develop with 22%
building coverage, which is representative of single-story commercial development in the
City, and assumes surface parking and landscaping requirements consistent with current
standards.
The proposed General Plan includes 7,255.7 acres of residentially designated lands within the
City limits, and includes two land use designations for residential; Low Density Residential
(LDR) and Medium/High Density Residential (M/HDR). The General Plan Update has the
potential to result in a total of 25,585 LDR units and 6,017 M/HDR units in the City limits,
which would be an increase of 8,114 residential units, compared to the existing residential
development within City limits. The Low Density Residential Land Use Designation allows for 0
to 4 single-family residential units per acre and applies to existing and vacant lots, subdivisions,
country club communities, and the clustering of condominiums or town homes with common
area amenities. LDR also allows for equestrian uses on lots of 1/2 acre or larger. The M/HDR
Land Use designation allows for 0 to 16 attached or detached dwelling units on smaller lots, and
provides for multi-family units including condominiums, town homes and apartments.
Commercial land use designations have been grouped into one of the following categories:
General Commercial; Tourist Commercial; or Village Commercial. The total commercial
acreage under the General Plan Update within City limits is 1,005.1 and consists of 669.3 acres
that have been developed and 335.8 acres that are currently vacant. These acreages correspond to
6,414,036 square feet of existing commercial development and the potential for the development
of an additional 3,218,039 square feet at build out. Thus, the total commercial square footage in
the City limits at build out will be 9,632,074 square feet.
The Major Community Facilities land use designation, including schools, government buildings,
and service facilities, makes up 446.5 acres consisting of 252.7 developed acres and 193.8 acres
that are currently vacant. The land use designations assigned for Open Space include Natural and
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Recreational lands. Natural Open Space consists of 6,933.3 acres that are intended to be
preserved in perpetuity, including lands within the Santa Rosa and San Jacinto Mountains
National Monument, as well as public lands within the Santa Rosa Wilderness. It should be
mentioned that Natural Open Space lands within the said Monument and Wilderness areas are
federally managed public lands that are owned and regulated by the Bureau of Land
Management (BLM). Open Space Recreation consists of 4,392.2 acres that have been developed
and an additional 867 acres that are currently vacant but are designated for development as
recreational open space, golf courses, and watercourses. Street rights-of-way consist of 1,764.6
acres that have been developed as roadways and an additional 191.1 acres that have been
designated but remain undeveloped. As proposed, there are no designated industrial lands within
the City limits. All lands proposed for the industrial and light manufacturing land use
designations are located within the Sphere of Influence.
The Table below shows the proposed land use designations within City limits, along with the
developed and vacant acreages and existing and proposed unit development associated with
residential and commercial land uses. Based on the total developed and undeveloped acreage,
land within the city limits is approximately 64 percent built out.
Table III-20
Proposed Land Use for City Limits
Land Use Designation
Developed
(Acres)
Vacant
(Acres)
Total
(Acres)
Existing
Units
Potential
Units
Total
Units
Low Density Residential 4,006.0 1,583.7 5,589.7 20,834 4,751 25,585
High Density Residential 1,292.4 373.6 1,666.0 2,655 3,362 6,017
Subtotal 5,298.4 1,957.3 7,255.7 23,489 8,114 31,603
Existing SF Potential SF Total SF
General Commercial 385.6 184.0 569.6 3,695,282 1,763,309 5,458,591
Tourist Commercial 206.6 138.9 345.5 1,979,889 1,331,106 3,310,996
Village Commercial 77.1 12.9 90.0 738,865 123,623 862,488
Subtotal 669.3 335.8 1,005.1 6,414,036 3,218,039 9,632,074
MC Facilities 252.7 193.8 446.5
Open Space Natural 2,171.6 4,761.7 6,933.3
Open Space Recreation 4,392.2 867.0 5,259.2
Street Rights-of-Way 1,764.6 191.1 1,955.7
Grand Total 14,548.8 8,306.7 22,855.5
Land use designation as set forth under the General Plan Update are consistent with the existing
development pattern and land uses. Land use designation and development as proposed are not
expected to divide residents, businesses, or existing communities. Rather, the General Plan
Update assures continuity between existing development and planned future development by
refining land use designations and assigning land uses to vacant lands within City limits. The
proposed Land Use plan is also consistent with the Coachella Valley Multiple Species Habitat
Conservation Plan (CVMSHCP), which sets forth the regional conservation planning efforts
including the City of La Quinta. Therefore, as proposed the General Plan Update would not
conflict with the established CVMSHCP and impacts to habitat conservation planning or natural
community conservation planning will be less than significant.
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Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
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Sphere of Influence
The Sphere of Influence represents the greatest potential for land use conversion, since only
11.5% of the area is currently developed. Under the General Plan Update, the Sphere of
Influence is primarily designated for low-density residential development, consisting of 7,378
acres out of the total 8,101.4-acre area. The remaining land use designations include 24.6 acres
of medium/high density residential, 285.1 acres of general commercial, 63.8 acres of
industrial/light manufacturing, 29.8 acres of major community facilities, and 319.9 acres for
street rights-of-way. Although the proposed land use development pattern is consistent with the
2002 General Plan, implementation would result in a substantial change to the existing character
within the Sphere of Influence.
The Sphere of Influence is currently governed by Riverside County and lands within the Sphere,
east of the current City limit, have been conceptualized for development as the Vista Santa Rosa
(VSR) Community. A VSR Land Use Concept Plan was approved by the Riverside County
Board of Supervisors on June 17, 2008. The approved Land Use Plan with acreage and potential
unit build out is shown in Table III-21 below. The following acreage is limited to that portion of
the Vista Santa Rosa Land Use Plan that overlaps with the Sphere of Influence as defined by the
proposed General Plan Update for La Quinta.
Table III-21
Riverside County Vista Santa Rosa Land Use
Vista Santa Rosa Developed Vacant Total
Existing
Units
Potential
Units
Total
Units
Estate Residential 136.9 1,160.3 1,297.2 580 580
Very Low Residential 37.9 887.5 925.4 888 888
Low Residential 235.8 4,003.5 4,239.3 786 6,005 6,791
Medium Residential 73.4 128.5 201.9 482 482
Medium High Residential 2.5 249.6 252.1 1,498 1,498
High Residential 23.6 135.5 159.0 1,422 1,422
Residential Subtotal 510.0 6,565.0 7,075.0 786 10,875 11,661
Existing
SF
Potential
SF Total SF
Commercial Retail 1.2 16.6 17.8 11,928 158,985 170,913
Commercial Tourist 0.0 119.9 119.9 - 1,149,107 1,149,107
Business Park 34.0 247.3 281.3 325,445 2,370,213 2,695,658
Community Center 7.5 112.2 119.6 71,617 1,074,468 1,146,086
Retail Subtotal 42.7 495.9 538.6 408,991 4,752,774 5,161,764
Public Facilities 28.2 40.2 68.4
Street Rights of Way 313.9 0.0 313.9
TOTAL 894.7 7,101.1 7,995.9
Includes that portion of the VSR Land Use Concept Plan that falls within the proposed Sphere of
Influence for La Quinta.
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Under the Riverside County land use designations, the Sphere of Influence area north of city
limits is designated as medium density residential with 2 to 5 units per acres. Currently, this area
only contains an estimated 15 homes. Under the Riverside County Land Use designation, this
area could build out to contain as many as 285 dwelling units. The following Table shows the
Riverside County Land Use designation for the area north of City limits within the Sphere of
Influence.
Table III-22
Riverside County Land Use North Sphere
Land Use Developed Vacant Total
Existing
Units
Potential
Units
Total
Units
Medium Density Residential 27.5 71.9 99.4 15 270 285
Street Rights of Way 6.2 0.0 6.2 0 0 0
Total 33.7 71.9 105.6 15 270 285
The following summarizes the build out potential under the current Riverside County land use
designations.
Table III-23
Riverside County Land Use Sphere Summary
Land Use Developed Vacant Total
Existing
Units/Sq.Ft.
Potential
Units/ Sq.Ft
Total Units/
Sq.Ft
Residential 537.5 6,636.9 7,174.4 801 11,145 11,946
Retail 42.7 495.9 538.6 408,991 4,752,774 5,161,764
Public Facilities 28.2 40.2 68.4
Street Rights of
Way 313.9 - 313.9
Total 928.4 7,173.0 8,101.5
The La Quinta General Plan Update proposes different land use intensities compared to those set
forth under the Riverside County Land Use Plan. As proposed, the La Quinta General Plan
Update would result in the development of up to 21,270 residential units, 2.7 million square feet
of commercial, and 611,408 square feet of industrial land uses within the Sphere of Influence
east of City limits.
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Table III-24
General Plan Update East Sphere Land Use
Vista Santa Rosa Developed Vacant Total
Existing
Units
Potential
Units
Total
Units
Low Residential 524.0 6,754.84 7,278.82 786 20,265 21,051
Medium High Residential 0.24 24.36 24.6 0.0 219 219
Residential SubTotal 524.2 6,779.2 7,303.4 786 20,484 21,270
Sq. Ft. Sq. Ft. Total SF
General Commercial 28.57 256.57 285.14 273,792 2,458,762
2,732,554
Industrial/Lgt. Mfg. 0.0 63.8 63.8 0.0 611,408 611,408
MC Facilities 28.17 1.61 29.78
Street Rights-of-Way 313.74 313.7
TOTAL 894.7 7,101.2 7,995.9
Includes that portion of the Sphere that is located east of the city limits.
As proposed under the General Plan Update, that portion of the Sphere of Influence north of the
existing city limits would be developed as low density residential at 0 to 4 units to the acre,
which is slightly less (53 units) than that proposed under the County’s land use designation.
Table III-25
General Plan Update Land Use North Sphere
Land Use Developed Vacant Total
Existing
Units
Potential
Units
Total
Units
Low Density Residential 27.5 71.9 99.4 15 216 231
Street Right of Way 6.19 0 6.19
Total 33.7 71.9 105.6 15 216 231
Only 928 acres of the Sphere of Influence are currently developed, with the remaining acreage,
89% of the total area, vacant. The following table details the existing and proposed land use
designations within the Sphere of Influence, including the total number of existing dwelling units
and square footage associated with commercial and industrial land uses as set forth under the
General Plan Update. The proposed land use plan has the potential to result in the development
of 21,281 low-density residential units, 219 high-density residential units, 2,732,557 square feet
of commercial, and 611,408 square feet of industrial and light manufacturing within the entire
Sphere of Influence.
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Table III-26
General Plan Update Land Use Sphere Summary
Land Use Developed Vacant Total
Existing
Units/Sq.Ft.
Potential
Units/ Sq.Ft
Total
Units/ Sq.Ft
LD Residential 551.5 6,826.6 7,378.1 801 20,480 21,281
M/HD Residential 0.2 24.4 24.6 -- 219 219
General Commercial 28.6 256.6 285.1 273,760 2,458,797 2,732,557
Industrial/Lgt. Mfg. 0.0 63.8 63.8 0.0 611,408 611,408
MC Facilities 28.17 1.61 29.8
Street Right of Way 319.93 0.0 319.9
Total 928.4 7,173.0 8,101.4
Development within the Sphere of Influence is not expected to occur in the short term. There is
limited infrastructure currently available, and existing economic conditions do not favor
expansion at this time. However, in the mid- to long-term, the land use designations assigned
under the General Plan Update are expected to be developed accordingly.
The proposed land use plan represents an intensification of land use development compared to
the existing conditions. When compared to build out conditions as defined by the Riverside
County Land Use designations, the proposed General Plan Update would result in a substantial
increase in the development of residential land uses, but a decrease in commercial development.
Land uses proposed under the General Plan Update will not divide or displace existing homes or
businesses. However, the proposed land use designations would result in an intensification of
residential densities, which has the potential to substantially change the existing character within
the Sphere of Influence. The character of the existing development within the Sphere of
Influence has the potential to be transformed from a low-density rural community to an urban
low-density residential community through intensification of land use development.
The General Plan includes policies and programs designed to provide buffers between residential
and commercial or industrial land uses, and the City’s Municipal Code includes standards that
require any non-residential development to appropriately protect surrounding residential
development. Nonetheless, the intensification of the proposed residential densities within the
Sphere of Influence as proposed under the General Plan Update have to potential to conflict with
the County’s existing Vista Santa Rosa Land Use Concept Plan, which may result in significant
impacts to residential land uses. However, the General Plan Update requires the preparation of a
master plan prior to annexation of this area, which reflects the character of Vista Santa Rosa. The
development of this master plan is required to involve the community, and reflect the
neighborhood’s character.
As described above, the City has found that annexation of lands in the eastern Sphere would
have a negative fiscal impact on the City. Although past annexation requests were not completed,
conditions have not changed since this analysis was undertaken, and it would be expected that
annexation proposals in the future would have a similarly negative fiscal impact. The General
Plan includes policies that require both the preparation of fiscal impact analyses for annexation
proposals, and a Development Agreement in association with annexation. The Development
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Agreement would establish the parameters for development, and would include mitigation fee
payments for projects that are fiscally negative for the City. These Development Agreements
would eliminate the potential fiscal impacts to the City.
The imposition of these policies on future annexation proposals will assure that potential impacts
associated with land use planning are less than significant.
Summary of Impacts
Changes in land use designations as proposed in this General Plan Update do not significantly
differ from the 2002 General Plan. Rather, land use designations have been re-characterized and
consolidated to provide for more concise land use designation descriptions and a simplified land
use map. Each land use designation as set forth in the General Plan Update is summarized below:
Low Density Residential, (LDR) (0-4 dwelling unit per gross acres): Allows for larger lot single-
family residential development, subdivisions, country club communities, and the clustering of
condominiums or town homes with common area amenities. Equestrian uses are allowed on lots
of one acre or larger. This is the most common land use designation in the City.
Medium/High Density Residential, (M/HDR) (0-16 dwelling units per gross acres): Allows single
family attached and detached units on smaller lots – particularly in the Cove. Multi-family units
including condominiums, town homes and apartments with common area amenities are also
appropriate in this designation.
General Commercial (GC): Allows larger community scale shopping centers on parcels 20 acres
or larger in size along major arterials. Uses include a range of commercial activities, all types of
retail sales, grocery stores, automobile sales, professional and medical office buildings,
restaurants and similar activities. Also allows for Mixed Use developments, with combined
residential and retail uses.
Tourist Commercial (TC): Allows resort hotels, tourist commercial retail developments,
recreational uses, restaurants and timeshare or fractional ownership. Allows for resort mixed use
activities, such as single and multi-family residential units, golf courses, timeshares, RV parks
and resorts with the preparation of a Specific Plan.
Village Commercial (VC): Allows retail, professional office, hotels and pedestrian oriented retail
development. This designation also allows for Mixed Use developments, which combine,
residential and retail uses in one project.
Industrial/Light Manufacturing (I/LM): Allows for non-polluting industrial uses operating
entirely in an enclosed structure. Outdoor storage is permitted if fully screened from view. Uses
include clean manufacturing, airport related uses, warehousing/distribution, and mini-storage.
Major Community Facilities: This designation is applied to existing or planned municipal,
educational, non-profit and/or religious organizations, or public service facilities. Typical land
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uses within this designation include civic centers and other governmental offices, public parking
lots, fire stations, schools, facilities for non-profit organizations and utility substations.
Open Space-Natural (OS-N): This designation includes natural open space areas including the
surrounding Santa Rosa Mountains and hillsides, nature preserves and conservation areas, trails,
drainage channels, and watercourses/flood control.
Open Space-Recreational (OS-R): This designation includes regional and local parks, golf
courses, golf-course resorts, and watercourses/flood control.
General Plan Planning Area
As proposed, the General Plan Update includes 30,957 acres consisting of 22,856 and 8,101
acres within City limits and the Sphere of Influence, respectively. Implementation of the
proposed General Plan has the potential to result in a total of 53,103 dwelling units on 14,658
acres of residentially designated lands, 12,364,631 square feet of commercial development on
1,290 acres, and 611,408 square feet of industrial/light manufacturing on 63.8 acres.
Implementation of the General Plan has the potential to result in the designation of 476.3 acres of
Major Community Facilities, 6,933.3 acres of Open Space Natural, 5,259.2 acres of Open Space
Recreation, and 2,275.6 acres of street rights-of-way. The following table summarizes land uses
proposed within the entire La Quinta General Plan Update planning area.
Table III-27
Proposed Land Use Summary
Land Use Designation
Developed
(Acres)
Vacant
(Acres)
Total
(Acres)
Existing
Units
Potential
Units
Total
Units
Low Density Residential 4,557.5 8,410.3 12,967.8 21,635 25,231 46,866
High Density Residential 1,292.6 398.0 1,690.6 2,655 3,582 6,236
Subtotal 5,850.1 8,808.3 14,658.4 24,290 28,813 53,103
Existing SF Potential SF Total SF
General Commercial 414.2 440.6 854.7 3,969,042 4,222,106 8,191,148
Tourist Commercial 206.6 138.9 345.5 1,979,889 1,331,106 3,310,996
Village Commercial 77.1 12.9 90.0 738,865 123,623 862,488
Subtotal 697.9 592.4 1,290.2 6,687,796 5,676,835 12,364,631
Industrial/Lgt. Mfg. 0.0 63.8 63.8 -- 611,408 611,408
MC Facilities 280.9 195.4 476.3
Open Space - Natural 2,171.6 4,761.7 6,933.3
Open Space - Recreation 4,392.2 867.0 5,259.2
Street Rights-of-Way 2,084.5 191.1 2,275.6
Grand Total 15,477.2 15,479.7 30,956.9
The General Plan Update is consistent with land use development strategies outlined in SCAG’s
Regional Comprehensive Plan. Both Plans share a common goal of achieving sustainable
community(s) through thoughtful and integrated land use planning. The proposed General Plan
Update will not result in significant impacts to land use planning relative to the Regional Plan.
See the circulation element for a discussion of impacts relative to the SCAG’s Regional
Transportation Plan.
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The entire planning area is located within the Coachella Valley MSHCP fee area, with
conservation lands limited to the Santa Rosa Mountains, which are designated as Open Space
Natural. As proposed, the General Plan Update for the La Quinta Planning Area does not conflict
with the established CVMSHCP and impacts to habitat conservation planning or natural
community conservation planning will be less than significant.
City Limits
The proposed land use designations within the City of La Quinta incorporated City limits will
not significantly affect the pattern of development that has already occurred. The overall
character is not expected to be significantly impacted by the proposed land use plan, nor is the
plan, or development facilitated by the plan, expected to divide an established community. The
proposed land use plan is consistent with existing land use designations and the current
development pattern and does not represent a significant change to land uses within the city
limits.
Sphere of Influence
As described above, the Sphere of Influence land use designations, as set forth under the General
Plan Update, represent the greatest divergence from existing development and land use
designations proposed under the Riverside County General Plan, with the exception of the
Sphere north of City limits. That portion of the Sphere of Influence located north of City limits is
consistent with land use development intensities set forth under the Riverside County General
Plan. Therefore, residential land use development in the Sphere north of the City limits as set
forth under the General Plan Update would not result in significant impacts to established land
use designations.
Land use designations within that portion of the Sphere of Influence that overlaps with the
County’s Vista Santa Rosa Land Use Concept Plan have the potential to result in significant
impacts. The General Plan update proposes residential land use intensities that could nearly
double the residential development proposed under the Vista Santa Rosa Land Use Concept. This
is primarily due to the difference in allowable densities for low density residential, which is set at
a maximum of 2 units to the acre under the VSR Plan and allows for up to 4 units to the acre
under the proposed General Plan Update. Therefore, as proposed residential land use
designations conflict with established residential land use designations set forth in the VSR Land
Use Concept Plan, implementation of the General Plan Update has the potential to result in
significant impacts to future development in the eastern Sphere of Influence. In order to reduce
potential impacts, a master plan that is reflective of the community’s wants and needs will be
developed for the Sphere of Influence.
As proposed under the General Plan Update, non-residential land use designations are more or
less consistent with the land use designations set forth under the VSR Land Use Concept Plan.
Land use designations for commercial development are somewhat reduced compared to the VSR
Plan. Although the General Plan Update proposes an industrial and light manufacturing land use
designation, the permitted activities are not expected to conflict with the land uses set forth under
the VSR Plan. Commercial/retail and industrial land uses proposed under the General Plan
Update are consistent with the County’s VSR Land Use concept, and no significant land use
impacts have been identified.
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3. Mitigation Measures
Potential land use incompatibilities are addressed through policies and programs set forth in the
General Plan and through adherence to the Municipal Code. A Master Plan of Development
specific for the Sphere of Influence will be prepared that is reflective of the community’s wants
and needs. Development within the Sphere of Influence shall be subject to policies set forth in
the said Master Plan. The General Plan also includes policies and programs designed to assure
that adequate infrastructure is available prior to development occurring in an area; and that land
use compatibility and neighborhood character be preserved throughout the City and Sphere.
These policies and programs reduce the potential impacts associated with land use and planning
to less than significant levels. No mitigation is required.
Mineral Resources J.
Introduction
The City of La Quinta is located within a region known as the Palm Springs Production-
Consumption Region, containing significant mineral deposits, including sand and gravel, which
are important mineral resources for the state’s economy. The California Division of Mines and
Geology has classified areas throughout the Palm Springs Production-Consumption Region with
different mineral resource zones based on the value of resources available within the ground.
This discussion assesses impacts on mineral resources from future growth and development
brought on by the La Quinta 2035 General Plan Update. It also provides mitigation measures to
reduce impacts on mineral resources.
Thresholds of Significance/Criteria for Determining Significance
Article 5, Section 15064 of the CEQA Guidelines provides guidance for determining the
significance of the environmental effects caused by a project. Appendix G of the CEQA
Guidelines provides a list of environmental factors that potentially may be affected by
completion of a project. The La Quinta 2035 General Plan Update would have a significant
effect on Mineral Resources if it is determined the plan:
a) Results in the loss of availability of a known mineral resource that would be of value
to the region and the residents of the state.
b) Results in the loss of availability of a locally important mineral resource recovery site
delineated on a local general plan, specific plan or other land use plan.
1. Existing Conditions
The State of California has recognized the importance of mineral resources for construction
materials and other economic purposes. Mining and extraction of mineral resources continues to
be threatened by urbanization and development in areas where important mineral resources exist.
The California Surface Mining and Reclamation Act of 1975 (SMARA) addresses the loss of
regionally significant mineral deposits to urban development.
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The Act requires the Department of Conservation to create Production-Consumption Regions,
which are areas where significant mineral resources of statewide importance and regional
significance are produced and consumed, and a classification system that identifies lands where
significant mineral resource deposits are located. As mentioned earlier, La Quinta is located in
the Palm Springs Production-Consumption Region. The Palm Springs Production-Consumption
Region covers approximately 631 square miles of the Coachella Valley from near Cabazon to
Thermal49. Small portions of southern La Quinta, including lands south of Avenue 60, are
located outside the Palm Springs Production-Consumption Region, and therefore are not located
within a Mineral Resource Zone. Lands within the Production-Consumption Region are
classified according to the presence of valuable mineral resources. La Quinta has two Mineral
Resource Zones, MRZ-1 and MRZ-3. These zones are shown in Exhibit III-11. The definition of
each Mineral Resource Zone is provided below50:
MRZ-1: Areas where adequate information indicates that no significant mineral deposits
are present, or where it is judged that little likelihood exists for their presence.
MRZ-3: Areas containing known or inferred mineral deposits, the significance of which
cannot be evaluated from available data.
As seen in Exhibit III-11, the majority of incorporated regions of La Quinta and the Sphere of
Influence are located in MRZ-1, or areas where adequate information indicates that no
significant mineral deposits are present, or are likely to occur. Most areas within MRZ-1,
particularly within incorporated La Quinta, are urbanized and developed. Land designated MRZ-
1 in the Sphere of Influence is mostly agricultural land with small residential subdivisions and
large lot residential.
Lands that fall under the MRZ-3 designation make up a small portion of La Quinta. These areas
are known to contain mineral deposits, however there have been no evaluations on the
significance of these resources. The MRZ-3 designation is found only in the southwestern
portion of the City, including along the Coral Reef Mountains and within the Cove area. Aside
from the development that already exists within the Cove, the majority of land in the MRZ-3
zone is designated as open space. The Open Space designation does not permit mining activities,
and requires the land to be preserved in its natural state. A small portion of MRZ-3, located just
north of Avenue 60 and west of Madison, is undeveloped vacant land designated for low density
residential development.
49 “Update of Mineral Land Classification for Portland Cement Concrete-Grade Aggregate in the Palm Springs
Production-Consumption Region, prepared by California Department of Conservation, California Geologic
Survey, 2007. 50 “Update of Mineral Land Classification for Portland Cement Concrete-Grade Aggregate in the Palm Springs
Production-Consumption Region; Special Report 198,” prepared by California Department of Conservation,
California Geologic Survey, 2007.
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2. Project Impacts
The General Plan Update will facilitate new development or redevelopment throughout the City
and Sphere. There are no mining operations occurring within the Planning Area.
The majority of lands within the City are developed. Remaining vacant lands include infill lots,
and scattered parcels located primarily within the Cove area and southwestern portion of the City
Limits, which may develop according to land use designations proposed by the General Plan
Update.51 As shown in Exhibit III-11, these areas are located in MRZ-3, or areas containing
known or inferred mineral deposits, the significance of which cannot be evaluated from available
data. These areas, however, are surrounded by urban development, and mineral extraction
activities are incompatible and unlikely on remaining vacant parcels.
According to Special Report 198, prepared by the California Department of Conservation, other
areas within the Coachella Valley, including the Whitewater area, and within the foothills north
and east of Indio, are more suitable for mineral extraction.52 The General Plan Update maintains
similar land use designations to those previously in effect on City parcels in the MRZ-3 area, and
does not provide land use designations conducive for mineral extraction. Therefore,
implementation of the General Plan Update does not result in loss of availability of locally-
important mineral resource considered valuable to the region and state, and does not result in the
loss of availability of mineral resource recovery sites delineated on a local general plan, specific
plan or other land use plan. Impacts on mineral resources caused by the implementation of the
General Plan Update will be less than significant.
The General Plan Update will also facilitate new development within the Sphere of Influence. As
mentioned earlier, however, the majority of these lands are located within the MRZ-1
designation, or an area determined as having no significant mineral resource deposits. Currently,
this area is used for agricultural purposes, and there are no known mineral leases, claims, or
prospects located in the Sphere of Influence or vicinity. Therefore, implementation of the
General Plan Update does not result in loss of availability of locally-important mineral resource
considered valuable to the region and state, and does not result in the loss of availability of
mineral resource recovery sites delineated on a local general plan, specific plan or other land use
plan. Implementation of the General Plan Update, therefore, will have no impact on mineral
resources within the Sphere of Influence.
3. Mitigation Measures
None Required.
Mitigation Monitoring and Reporting None Required.
51 http://maps.google.com, accessed July 5, 2011. 52 “Update of Mineral Land Classification for Portland Cement Concrete-Grade Aggregate in the Palm Springs
Production-Consumption Region; Special Report 198,” prepared by California Department of Conservation,
California Geologic Survey, 2007.
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Noise K.
Introduction
This section describes existing noise conditions in the General Plan Update Planning Area and
analyzes the potential impacts caused by various potential noise sources associated with build
out of the proposed General Plan Update. An acoustical analysis has been prepared in
conjunction with the General Plan Update, and the results have been used to prepare the analysis
of noise impacts presented in this section of the EIR.53 The study is included in its entirety in
Appendix F of this EIR. This section also sets forth noise-related mitigation measures, which
will effectively reduce construction, operational and traffic noise impacts to acceptable levels.
Thresholds of Significance/Criteria For Determining Significance
The following thresholds or criteria are derived from Appendix G of the CEQA Guidelines,
which are used to determine the level of potential effect. Build out of the proposed General Plan
will have a significant effect on noise levels if the project results in the following:
a.) Exposure of persons to or generation of noise levels in excess of standards established in
the local general plan or noise ordinance, or applicable standards of other agencies;
b.) Exposure of persons to or generation of excessive ground-borne vibration or ground-
borne noise levels;
c.) Causes a substantial permanent increase in ambient noise levels in the project vicinity
above levels existing without the project;
d.) Causes a substantial temporary or periodic increase in ambient noise levels in the project
vicinity above levels existing without the project;
e.) If located within an airport land use plan or, where such a plan has not been adopted,
within two miles of a public airport or public use airport, a project would expose people
residing or working in the project area to excessive noise levels;
f.) If located within the vicinity of a private airstrip, a project would expose people residing
or working in the project area to excessive noise levels.
1. Existing Conditions
Noise is defined as “unwanted sound.” Unwanted sound includes noise that interferes with
normal activities, inflicts physical harm on individuals, or causes adverse effect on health.
Excessive noise or prolonged exposure to noise can contribute to temporary and permanent
impairments, such as hearing loss, fatigue, stress, sleep deprivation, anxiety and annoyance.
Although noise has been accepted as a necessary by-product of urban development, it can
become an environmental hazard. A variety of components of the urban environment generate
53 “City of La Quinta General Plan Update Noise Element Technical Report,” prepared by Urban Crossroads, Inc.,
June 3, 2011.
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noise; these include construction equipment and activities, motor vehicles, air traffic, mechanical
equipment, household appliances, and other sources.
Existing Noise
The General Plan Update Planning Area enjoys a moderately quiet noise environment, especially
within residential areas. Primary sources of noise throughout the City are caused primarily by
motor vehicle traffic on City streets, particularly major roadways. This includes general
operation of cars, trucks, and bus lines. Other noise generators in the City include those
associated with commercial uses and construction noise. These noises include loading dock
operations, trucks entering and leaving commercial centers, and mechanical equipment, such as
fans, motors, and compressors.
Construction noise is generally short-term and is generated by construction equipment, including
trucks, bulldozers, graders, concrete mixers, pile drivers and other mobile and fixed construction
equipment.
This General Plan Update does not propose any construction, and as such, does not evaluate
specific construction related noises. Rather, this report gives a planning level analysis of future
impacts that will occur within the City and Sphere of Influence.
The Sphere of Influence consists primarily of agricultural and vacant lands, and vehicular traffic
is much less than that found throughout the City. As such, the Sphere of Influence enjoys a quiet
noise environment. Within the eastern Sphere, noise is generated from periodic flights and
general aviation operations at the Jacqueline Cochran Regional Airport. The airport is located
adjacent to the eastern boundary of the eastern Sphere, east of Harrison Street. Within the
northern Sphere of Influence, noise is also generated from occasional overhead flights associated
with the Bermuda Dunes Airport, which is located two miles northeast.
The effects of noise increase dramatically when incompatible land uses are located next to one
another. Potential land use incompatibilities include residential areas or other sensitive receptors
located near industrial and commercial uses.
Noise Fundamentals
The most common unit of measure for noise levels is the A-weighted decibel (dBA) scale. The
A-weighted decibel scale reflects only those frequencies that are audible to the human ear. The
decibel scale threshold ranges from 0 dBA to 140 dBA, with higher decibels considered painful
to the human ear. The most common sounds range is between 40 dBA (very quiet) and 100 dBA
(very loud). For example, a normal conversation at three feet is approximately 60 dBA, whereas
a loud jet engine flying overhead generates 110 dBA.
The logarithmic nature of the decibel means that a doubling of sound energy of a noise source
results in an increase in the decibel rating of only 3 dBA. For example, the doubling of traffic
noise on a busy street will generally only increase sound levels by 3 dBA. Changes of 3 dBA are
barely perceptible to the human ear. In order for a human ear to perceive a sound as being twice
as loud, the sound must increase by nearly 10 dBA. In community settings, changes in noise
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levels occur over a period of years. Changes of 5 dBA are readily perceptible and changes of 10
dBA are considered twice as loud.
The City of La Quinta measures intensity of sound and bases noise standards on the Community
Noise Equivalent Level (CNEL). CNEL is the average intensity of a sound over a 24-hour
period. It accounts for the decrease in background noise levels that occur during evening and
nighttime hours, as well as people’s increased sensitivity to noise during these times. Penalty
factors are added for sounds that occur in evening and nighttime hours.
Noise sources can result from “line sources” or “point sources”. Line sources include linear
sources of noise, such as a freeway or busy street. Point sources are generally stationary, such as
HVAC units or air compressors. Noise transmission is affected by a variety of factors, such as
temperature, wind speed and direction, as well as the type of ground surface. Soft ground
surfaces tend to reduce sound levels better than hard surfaces. This reduction of sound intensity
caused by surfaces, walls, vegetation or other material is called attenuation. A drop off rate of 4.5
dBA per doubling distance is typical across soft ground. In comparison, hard ground, such as
concrete, stone, and hard packed earth reduce sound by 3.0 dBA per doubling distance.
Effective noise barriers, such as walls or berms, can help reduce noise levels by 10 to 15
decibels. These types of barriers can provide relief from traffic noise. Vegetation, on the other
hand, is less effective for reducing noise levels. For a noise barrier to work, walls need to be high
enough and long enough to block the view of a road.
Regulatory Setting
The State has established guidelines for appropriate noise level ranges for a variety of land uses
within a community. The range of allowable exterior noise levels for various land uses is shown
in Exhibit III-12. This matrix is used to ensure noise compatibility of proposed land uses and
helps predict the future noise environment. Where sensitive land uses will be exposed to noise
levels of 60 dBA CNEL or higher, an acoustical study may be required. In residential areas in
California, the standard is a CNEL of 65 dBA. Mitigation measures are required where sensitive
land uses will be exposed to noise levels greater than 65 dBA CNEL. Interior noise standards are
provided by Chapter 12 of the California Building Code. According to the Code, interior noise
levels from exterior sources shall not exceed 45 dB in any habitable room. As discussed below,
the City of La Quinta uses the noise levels shown in Exhibit III-13, as a guideline to achieve
long-term noise compatibility for land uses.
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City of La Quinta Noise Ordinance
The City of La Quinta Municipal Code Section 9.100.210, Noise Control, establishes base
ambient noise level limits for noise sensitive and other non-residential uses based on time of day.
Table III-28 below shows the exterior noise limits established by the City. Noise sensitive land
uses include residential uses, schools, hospitals, churches, daycare, and similar uses. All other
uses must comply with the “Other Non-Residential” standard.
Table III-28
Exterior Noise Limits
Noise level
that may not
be exceeded
for a
cumulative
period more
than…
Noise Standard at Affected Land Use
Noise Sensitive Other Non-residential
Daytime
7 a.m. – 10 p.m.
Nighttime
7 a.m. – 10 p.m.
Daytime
7 a.m. – 10 p.m.
Nighttime
7 a.m. – 10 p.m.
30 min/hr 60 dBA 50 dBA 75 dBA 65 dBA
15 min/hr 65 dBA 55 dBA 80 dBA 70 dBA
5 min/hr 70 dBA 60 dBA 85 dBA 75 dBA
1 min/hr 75 dBA 65 dBA 90 dBA 80 dBA
Anytime 80 dBA 70 dBA 95 dBA 85 dBA
Note: For the purposes of this section, the term “cumulative period” means the number of
minutes that a noise occurs within any hour, whether such minutes are consecutive or not.
Source: “City of La Quinta General Plan Update Noise Element Technical Report, Urban Crossroads, June 3, 2011.
The Municipal Code also establishes limits on construction activity during the day. Construction
noise is considered temporary, but can often be disruptive for surrounding land uses. Section
6.08.050 of the Municipal Code limits construction to the following hours:
October 1st through April 30th: Monday – Friday: 7:00 a.m. to 5:30 p.m.
Saturday: 8:00 a.m. to 5:00 p.m.
Sunday and Holidays: None
May 1st through September 30th: Monday – Friday: 6:00 a.m. to 7:00 p.m.
Saturday: 8:00 a.m. to 5:00 p.m.
Sunday and Holidays: None
In addition, the Municipal Code Section 9.100.220 states, “No use, except a temporary
construction operation, shall be permitted which generates inherent and recurrent ground
vibration perceptible, without instruments, at the boundary of the lot on which the use is
located.”
Existing Noise Level Measurements in the General Plan Area
The existing noise environment in the City was determined by both short-term and long-term
noise level monitoring. There were thirteen short-term measurements conducted near major noise
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sources throughout the Planning Area. These short-term measurements were monitored for a
minimum time period of ten-minutes. Table III-29 below shows the results of the short-term
monitoring. Short-term noise levels ranged between 57.7 dBA Leq and 69.3 dBA Leq. When
expressed in terms of the 24-hour CNEL noise level, the noise levels ranged from 61.5 dBA
CNEL to 72.9 dBA CNEL. Data provided by Table III-29 shows elevated short-term exterior
ambient noise levels above 65 dBA CNEL at locations near residential uses and schools,
including locations S7 and S9.
Table III-29
Existing (Ambient) Short-Term Noise Level Measurements
Receptor
Location1 Description
Time of
Measurement
Primary Noise
Source
Noise
Levels
(Leq
dBA)
Noise
Levels
(dBA
CNEL)
S1
Located 100 feet from the
Washington Street
centerline north of the
Fred Waring Drive
intersection. 3:00 p.m.
Traffic on
Washington Street 66.1 68.4
S2
Located near the
Jefferson Street and Fred
Waring Drive intersection
at an existing Walgreens. 3:17 p.m.
Traffic on
Jefferson
St. and Fred
Waring Dr. 69.3 72.9
S3
Located near the
Eisenhower Health center
east of the Washington
Street centerline. 3:43 p.m.
Traffic on
Washington Street 69.3 71.6
S4
Located near the School
District Offices at the
intersection of 48th
Avenue and Dune
Palms Road. 4:11 p.m.
Traffic on Avenue
48 66.5 67.1
S5
Located approximately
100 feet east of the
Jefferson Street centerline
north of the 50th Avenue
intersection at the existing
commercial center. 10:27 a.m.
Traffic on
Jefferson
St. 64.3 68
S6
Located 50 feet east of
the centerline in the front
yard of 51915 Avenue
Bermudas across from the
community park south of
the 52nd Avenue
intersection. 11:12 a.m.
Traffic on Avenue
Bermudas 66.2 71.3
S7
Located south of 52nd
Avenue at the Cahuilla
Desert Academy School. 11:55 a.m.
Traffic on 52nd
Avenue 62 66.6
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Table III-29
Existing (Ambient) Short-Term Noise Level Measurements
Receptor
Location1 Description
Time of
Measurement
Primary Noise
Source
Noise
Levels
(Leq
dBA)
Noise
Levels
(dBA
CNEL)
S8
Located adjacent to the
single-family homes near
the intersection of
Avenue Bermudas and
Calle Arroba. 11:29 a.m.
Traffic on Avenue
Bermudas 59.2 64.3
S9
Located east of Madison
Street at the Troon Way
intersection near existing
single-familyhomes. 1:10 p.m.
Traffic on
Madison
Street 64.4 67.5
S10
Located 100 feet west of
the Harrison Street
centerline south of the
Airport Blvd. intersection. 12:16 p.m.
Traffic on
Harrison
Street 62.1 65.7
S11
Located north of 50th
Avenue centerline at the
existing Boy and Girls
Club. 10:46 a.m.
Traffic on 50th
Avenue 57.7 61.5
S12
Located 50 feet east of
the Monroe Street
centerline south of the
60th Avenue intersection
and the existing
residential uses. 12:40 p.m.
Traffic on Monroe
Street 60.4 64
S13
Located 100 feet west of
the Jefferson Street
centerline between 52nd
and 54th Avenue at the
proposed residential uses. 1:30 p.m.
Traffic on
Jefferson
Street 66.7 71
Source: City of La Quinta General Plan Update Noise Element Technical Report,” prepared by Urban Crossroads,
Inc., June 3, 2011
1. See Exhibit III-13 for the location of the monitoring sites.
In addition, seven long-term measurements were conducted near sensitive land uses throughout
the Planning Area. Long-term noise measurements were monitored for a 24-hour period to assess
ambient hourly noise levels. A summary of long term measurements is shown in Table III-30,.
Hourly noise levels at these locations ranged between 43.1 dBA Leq to 72.6 dBA Leq; the
weighted 24-hour noise levels ranged from 58.9.5 dBA CNEL to 72.7 dBA CNEL. Data indicate
that traffic peak hours generally resulted in the highest noise levels. Data provided in Table III-
30 shows elevated long-term exterior ambient noise levels above 65 dBA CNEL at site L7,
which is located near single-family homes at the intersection of Jackson Street and 50th Avenue.
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Table III-30
Existing (Ambient24-hour Noise Level Measurements
Receptor
Location1 Description
Time of
Measurement
Primary Noise
Source
Hourly
Noise
Levels
(Leq dBA)
Daily
Noise
Levels
(dBA
CNEL)
L1
Located north of
Westward Ho Drive at
La Quinta Park
across from the La
Quinta High School
baseball fields.
February 2-3,
2011
Traffic on
Westward Ho
Drive, Park
Activities,
Activities at La
Quinta High
School 44.9 - 63.6 60.2
L2
Located north of
Highway 111 on
southern portion of
the commercial center
west of La Quinta Dr.
February 2-3,
2011
Traffic on Highway
111 50.4 - 64.1 65.3
L3
Located near the
Washington St. and Via
Marquessa intersection
adjacent to existing
medical offices.
February 2-3,
2011
Traffic on
Washington Street 58.1 - 71.6 72.7
L4
Located north of
Coachella Drive and
Eisenhower Drive
intersection at the
Legacy Villas.
February 2-3,
2011
Traffic on
Eisnhower Drive,
Ambient 47.6 - 56.1 59.3
L5
Located next to the Crab
Pot Restaurant on
Avenida La Fonda in
"The Village".
February 2-3,
2011
Traffic on Ave. La
Fonda,
Ambient within
The Village 43.1 - 65.4 58.9
L6
Located northeast of the
52nd Avenue and
Jefferson Street inter-
section at land uses
proposed as multifamily
residential.
February 2-3,
2011
Traffic on 52nd
Ave. and
Jefferson St. 48.7 - 60.3 62.2
L7
Located on the northeast
corner of Jackson Street
and 50th Avenue near
existing single-family
homes.
February 2-3,
2011
Traffic on Jackson
St. 52.6 - 72.6 71.4
Source: City of La Quinta General Plan Update Noise Element Technical Report,” prepared by Urban Crossroads,
Inc., June 3, 2011
1. See Exhibit III-13 for the location of the monitoring sites.
Terra Nova/La Quinta General Plan EIR
Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
III-144
Primary Noise Sources
As discussed earlier, existing noise sources in La Quinta are generally associated with motor
vehicle traffic. This includes truck traffic and noise generated from local buses. Other noise
sources throughout the Planning Area include air traffic generated from the Jacqueline Cochran
Regional Airport and Bermuda Dunes Airport, noise from commercial and local business
operations, including truck loading and operation of mechanical equipment, and construction
noise, which impacts development in proximity to the construction activities and equipment.
Each of these noise sources is discussed categorically, below.
Motor Vehicle Noise
Motor vehicle traffic is the largest noise generator throughout the General Plan Update Planning
Area, particularly in the urbanized portions of the City Limit. The level of noise depends on
volume of traffic, vehicular speed, and number of trucks in the flow of traffic. Engine vibration,
vehicle tires, and vehicle exhaust systems also affect noise levels. Therefore, roads with heavier
traffic volumes, higher speeds, and larger mix of trucks will generally have high noise levels.
Table III-31 shows the traffic flow distribution on select roadway types in La Quinta, including
Eisenhower Drive, which represents a Primary Roadway, Washington Street, which represents a
Major roadway, and Highway 111. Highway 111 generally has the highest percentage of
medium and heavy truck use, and Washington Street the highest percentage of automobiles.
Traffic volumes along each selected roadway are greatest during daytime hours, or between 7 am
and 7 pm.
Table III-31
City of La Quinta Hourly Traffic Flow Distribution
Motor-Vehicle Type
Daytime
(7 am to 7 pm)
Evening
(7 pm to 10 pm)
Night
(10 pm to 7 am)
Total %
Traffic Flow
Collector, Secondary,
Primary1
Automobiles 76.8% 12.9% 10.3% 95.42%
Medium Trucks 84.1% 6.8% 9.1% 3.37%
Heavy Trucks 79.4% 4.8% 15.9% 1.21%
Major, Augmented
Major2
Automobiles 81.4% 10.4% 8.2% 96.05%
Medium Trucks 86.7% 5.3% 8.0% 2.65%
Heavy Trucks 89.2% 3.4% 7.3% 1.30%
Highway-1113
Automobiles 73.4% 9.7% 16.9% 91.40%
Medium Trucks 80.3% 5.5% 14.2% 6.49%
Heavy Trucks 71.7% 6.5% 21.8% 2.11%
Source: City of La Quinta General Plan Update Noise Element Technical Report,” prepared by Urban Crossroads, Inc., June 3, 2011
1 Based on axle counts on Eisenhower Drive between Calle Nogales and Calle Chihuahua, a Primary roadway on February 15-16, 2011.
2 Based on axle counts on Washington Street between Avenue 48 and Avenue 50, a Major roadway on February 15-16, 2011.
3 Based the Caltrans District 8 2009 Annual Average Daily Truck Traffic Report.
Terra Nova/La Quinta General Plan EIR
Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
III-145
Existing noise levels along major roadways in the General Plan Update Planning Area are shown
on Table III-32. These levels were determined based on modeling that replicates the Federal
Highway Administration (FHWA) Traffic Noise Prediction Model FHWA-RD-77-108. The
FHWA Model calculates predicted noise levels through adjustments to the Reference Energy
Mean Emission Level (REMEL). Adjustments account for roadway classification, roadway
width, the total average daily traffic (ADT), percentage of total ADT that flows each hour in a
24-hour period, travel speed, roadway grade, angle of view, percentage of vehicle types,
including automobiles, medium trucks, and heavy trucks, and site conditions. Results are
weighted for a 24-hour period and then expressed as CNEL.
Noise contours provided in Table III-32 were calculated using “soft-site” conditions in order to
account for the effective noise attenuation over natural surfaces such as normal earth and ground
vegetation. As mentioned above, noise drops off at a rate 4.5 dBA per doubling of distance over
soft ground, as compared to 3.0 dBA per doubling of distance over hard ground, such as
concrete, stone, or hard-packed earth. Existing contours provided in the table represent a
conservative estimate, and do not account for noise barriers, topography, or roadway grades that
may affect ambient noise levels.
As shown in Table III-32, many of the Planning Area’s major roadways, including Highway 111,
Washington Street, Jefferson Street, Avenue 44, and Avenue 48, have existing noise levels
exceeding 65 dBA CNEL at 100 feet from centerline. Many of these roads pass near sensitive
land uses, such as residential neighborhoods, churches, and schools. Highway 111 is the only
roadway not located along sensitive land uses. Noise barriers, such as walls or berms, can help
reduce noise levels by 10 to 15 decibels, providing relief from traffic noise. In most cases, noise
walls separate residential uses from roadways.
Truck and Bus Routes
As mentioned above, higher volumes of heavy trucks and buses along roadways generally
increases noise impacts. Noise impacts from heavy trucks and buses are generated from braking
systems, shifting gears, and engine noise during acceleration. Exhibit III-14 shows existing bus
and truck routes throughout the Planning Area. Bus service throughout La Quinta is focused
along travel ways with regional links, and is concentrated along Highway 111, Washington
Street, and in portions of the Cove. Currently, there are no bus routes in the far southern portions
of the City or Sphere.
Terra Nova/La Quinta General Plan EIR
Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
III-147
Table III-32
Existing Noise Exposure Adjacent to General Plan Update Study Area Roadways
Road Segment
CNEL at
100 Feet
(dBA)
Distance to Contour (Feet) from
centerline
70 dBA
CNEL
65 dBA
CNEL
60 dBA
CNEL
55 dBA
CNEL
Washington St. n/o Fred Waring Dr. 70.8 113 243 524 1,128
Washington St. btwn Fred Waring & Miles 71.1 119 257 553 1,192
Washington St. btwn Miles & Hwy 111 70.2 104 223 481 1,036
Washington St. btwn Hwy 111 & Avenue 48 70.7 111 240 517 1,114
Washington St. btwn Avenue 48 & Eisenhower Dr 70.3 105 226 486 1,047
Washington St. btwn Eisenhower Dr & Avenue 50 69.4 91 196 423 910
Washington St. btwn Avenue 50 & Calle Tampico 68.8 83 178 383 826
Eisenhower Dr. btwn Washington St & Avenue 50 65.4 RW 107 230 496
Eisenhower Dr. btwn Avenue 50 & Calle Tampico 64.6 RW 94 203 438
Avenida Bermudas btwn Calle Tampico & Avenue 52 58.5 RW RW 80 172
Avenida Bermudas btwn Avenue 52 & Calle Durango 62.9 RW 73 156 337
Adams St. btwn Westward Ho Dr & Hwy 111 64.6 44 94 203 437
Adams St. btwn Hwy 111 & Avenue 48 64.0 RW 86 186 401
Dune Palms Rd. btwn Westward Ho Dr & Hwy 111 62.9 RW 73 156 337
Dune Palms Rd. btwn Hwy 111 & Avenue 48 62.5 RW 68 146 314
Jefferson St. n/o Fred Waring 68.3 77 165 355 765
Jefferson St. btwn Fred Waring & Miles 68.8 83 180 387 833
Jefferson St. btwn Miles & Westward Ho Dr 68.3 77 166 357 768
Jefferson St. btwn Westward Ho Dr & Hwy 111 69.4 91 196 422 910
Jefferson St. btwn Hwy 111 & Avenue 48 69.4 91 195 420 905
Jefferson St. btwn Avenue 48 & Avenue 50 69.4 91 196 423 911
Jefferson St. btwn Avenue 50 & Avenue 52 67.1 64 139 299 645
Jefferson St. btwn Avenue 52 & Avenue 54 66.0 RW 116 251 540
Madison St. btwn Avenue 50 & Avenue 52 62.2 RW 65 139 300
Madison St. btwn Avenue 54 & Airport Blvd 64.3 RW 90 193 416
Madison St. btwn Airport Blvd & Avenue 58 62.7 RW 70 150 324
Madison St. btwn Avenue 58 & Avenue 60 58.5 RW RW 79 170
Monroe St. btwn Avenue 52 & Avenue 54 59.6 RW RW 94 203
Monroe St. btwn Avenue 54 & Airport Blvd 58.7 RW RW 81 176
Jackson St. btwn Avenue 54 & Airport Blvd 59.9 RW RW 98 211
Jackson St. btwn Airport Blvd & Avenue 58 58.3 RW RW 77 166
Jackson St. btwn Avenue 58 & Avenue 60 57.0 RW RW 63 136
Jackson St. btwn Avenue 60 & Avenue 62 56.6 RW RW 59 128
Van Buren St. btwn Avenue 52 & Avenue 54 61.3 RW 57 122 264
Van Buren St. btwn Avenue 54 & Airport Blvd 59.9 RW RW 98 211
Van Buren St. btwn Airport Blvd & Avenue 58 56.3 RW RW 57 122
Van Buren St. btwn Avenue 58 & Avenue 60 55.3 RW RW RW 105
Van Buren St. btwn Avenue 60 & Avenue 62 53.3 RW RW RW 77
Terra Nova/La Quinta General Plan EIR
Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
III-148
Table III-32
Existing Noise Exposure Adjacent to General Plan Update Study Area Roadways
Road Segment
CNEL at
100 Feet
(dBA)
Distance to Contour (Feet) from
centerline
70 dBA
CNEL
65 dBA
CNEL
60 dBA
CNEL
55 dBA
CNEL
Harrison St. btwn Airport Blvd & Avenue 58 63.3 RW 77 166 358
Avenue 44 e/o Washington St 68.5 80 172 370 797
Miles Ave. e/o Washington St 64.6 RW 93 201 434
Hwy 111 e/o Washington St 72.8 153 331 712 1,535
Hwy 111 e/o Adams St 73.0 159 343 738 1,590
Hwy 111 e/o Dune Palms 73.9 181 390 840 1,809
Avenue 48 e/o Washington St 65.7 52 112 241 520
Avenue 48 w/o Jefferson St 67.3 66 142 305 658
Avenue 50 e/o Washington St 64.4 RW 91 197 424
Avenue 50 w/o Jefferson St 64.5 RW 92 199 429
Avenue 50 e/o Jefferson St 64.6 RW 94 203 438
Calle Tampico
btwn Eisenhower Dr & Avenida
Bermudas 61.9 RW 62 134 289
Calle Tampico
btwn Avenida Bermudas &
Washington St 64.7 RW 95 204 440
Avenue 52 w/o Washington St 66.7 60 130 280 603
Avenue 52 w/o Jefferson St 65.9 54 116 249 537
Avenue 52 e/o Jefferson St 64.8 RW 96 208 448
Avenue 52 e/o Madison St 63.2 RW 76 164 354
Avenue 54 e/o Jefferson St 63.9 RW 84 181 390
Avenue 54 w/o Madison St 62.4 RW 67 145 312
Airport Blvd. e/o Madison St 57.4 RW RW 67 145
Avenue 58 w/o Monroe St 56.6 RW RW 60 129
Avenue 58 e/o Monroe St 55.1 RW RW 47 102
Avenue 60 e/o Madison St 58.1 RW RW 75 161
Avenue 60 e/o Monroe St 54.0 RW RW RW 85
Avenue 62 btwn Madison St & Monroe St 53.3 RW RW RW 78
Avenue 62 e/o Monroe St 52.3 RW RW RW 66
Avenue 62 e/o Jackson St 50.7 RW RW RW 52
Avenue 62 e/o Van Buren St 52.6 RW RW RW 69
Source: City of La Quinta General Plan Update Noise Element Technical Report,” prepared by Urban Crossroads, Inc., June 3, 2011
1 "RW" = Location of the respective noise contour falls within the right-of-way of the road
Terra Nova/La Quinta General Plan EIR
Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
III-149
Aircraft Noise
Two sources of aircraft noise have the potential to affect the noise environment in the City and
Sphere: the Jacqueline Cochran Regional Airport, and the Bermuda Dunes Airport. Each is
described individually below.
Jacqueline Cochran Regional Airport
The Jacqueline Cochran Regional Airport is a small regional airport located east of Harrison
Street, the eastern border of the Sphere of Influence. The airport houses approximately 127
aircraft, mostly single-engine airplanes, and air traffic consists of local flights or transients from
other small airports. As of December 2006, there were an average of 209 operations
(takeoffs/landings) a day, or over 70,000 annually. Of these operations, approximately 62% were
associated with transient general aviation.54
Lands adjacent to the airport are generally vacant and are under County of Riverside jurisdiction
and zoned for airport, industrial and agricultural uses.55 Although overflights may occasionally
be audible within the General Plan Update Planning Area, these impacts are not considered
significant. As shown on Exhibit III-15, aircraft noise does not generate a significant noise
impact. The noise contours of 65 dBA or greater are contained within the airport’s boundaries.
Bermuda Dunes Airport
The Bermuda Dunes Airport is a small privately owned commuter airport located approximately
two miles north of the northern City limits and Sphere of Influence. The airport lies just south of
Interstate 10, and west of Jefferson Street in Bermuda Dunes. The Bermuda Dunes Airport has
one east-west runway measuring approximately 5,000 feet in length. The airport averages
approximately 110 flights a day. Land uses surrounding the airport include residential, industrial
and commercial uses associated with the airport. According to the Riverside County Airport
Land Use Compatibility Plan, existing noise contours of 65 dBA or greater are contained within
the airport’s boundaries.56
54 “Airport Operation Statistics,” Jacqueline Cochran Airport,
http://www.rcjcra.com/AirportInformation/AirportStatistics/tabid/77/Default.aspx, accessed July 12, 2011. 55 As shown on Figure 3.20 “Final Draft Eastern Coachella Valley Area Land Use Plan,” Riverside County
General Plan, 2003. 56 “East County Airports Background Data: Bermuda Dunes and Environs,” Riverside County ALUCP,
December, 2004.
Terra Nova/La Quinta General Plan EIR
Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
III-151
Industrial and Commercial Noise
Industrial and commercial noise is generally associated with loading dock operations, trucks
entering and leaving commercial and industrial districts, and interior and exterior mechanical
equipment uses. These types of noises can have a varying degree of impact on adjacent land
uses. Land use compatibility issues may arise when residential development is located adjacent to
commercial/industrial areas, which generates noise from air conditioning units, truck deliveries and
the use of mechanical equipment. All land uses are required to comply with exterior noise levels set
forth in the City’s Municipal Code, as discussed above.
Construction Noise
Noise from construction activity is generated from construction equipment, including trucks,
graders, bulldozers, concrete mixers and portable generators. Increases to the ambient noise
environment from construction activities are short-term but can reach high levels, especially from
grading activities. Noise levels from heavy equipment can range between approximately 68 dBA to
100 dBA at a distance of 50 feet. These noise levels diminish rapidly with a doubling of distance
from the noise source at a rate of approximately 6 dBA per doubling distance .57
The City does not have construction noise standards; however, construction noise can be most
effectively controlled through compliance with locally established construction hours. As discussed
above, the Municipal Code has established day and time restrictions on construction activities.
Ground-borne Vibration and Ground-borne Noise Levels
Ground-born vibration and noise is generally associated with construction activity, such as pile
driving and grading, but is also generated from traffic. Vibration is defined as the periodic
movement of mass over time, and is described in units of velocity (inches per second). It is
discussed in decibel (dB) units in order to compress the range of numbers required to describe
vibration. The human threshold of perception for vibration is 65 Vdb, or 0.0018 inches/second,
and is not usually significant until 70 Vdb, or 0.0031 inches/second. Typical levels of ground
vibration range between 50 Vdb and 100 Vdb. Vibration caused by bus and heavy truck traffic,
for example, is generally around 65 Vdb. In comparison, construction related vibration can range
between 90 Vdb and 100 Vdb. Blasting from construction projects, for example, can be as high
as 100 Vdb. The effects of ground-borne vibration generally include movement of building
floors, rattling of windows, and rumbling sounds. Ground-borne vibrations associated with
construction and traffic attenuate rapidly as one moves away from the source. According to
Caltrans, vibration caused by truck traffic attenuates to below perception levels at distances
greater than 130 feet. 58
In order to minimize impacts from ground-borne vibration and noise, future noise sensitive land
uses should have limited exposure to truck routes, high traffic areas, and other ground-borne
vibration producing activities. The City should also ensure that new developments minimize
vibration impacts during construction. 59
57 “City of La Quinta General Plan Update Noise Element Technical Report,” prepared by Urban Crossroads, Inc.,
June 3, 2011. 58 Ibid. 59 “City of La Quinta General Plan Update Noise Element Technical Report,” prepared by Urban Crossroads, Inc.,
June 3, 2011.
Terra Nova/La Quinta General Plan EIR
Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
III-152
2. Project Impacts
The La Quinta General Plan Update will facilitate new development and redevelopment
throughout the City of La Quinta and Sphere of Influence. Build out of the General Plan Update
will generate increased noise levels associated with increased traffic, construction, and increased
commercial and industrial activity. In addition, increased development near the eastern boundary
of the eastern Sphere of Influence will potentially increase exposure to noise impacts associated
with the Jacqueline Cochran Regional Airport. In a similar fashion, new development within the
northern Sphere of Influence and the northern part of the City will also potentially increase
exposure to noise impacts associated with the Bermuda Dunes Airport. Each of these impacts is
discussed below.
Impacts Related to Noise Levels in Excess of General Plan or Noise Ordinance
As mentioned, the City of La Quinta currently regulates noise levels for sensitive land uses. The
City uses the noise levels shown in Exhibit III-12 above, as a guideline to achieve long-term
noise compatibility for land uses. For example, the maximum exterior noise level within
residential areas is a CNEL of 65 dBA. Mitigation measures are required where residential uses
will be exposed to noise levels greater than 65 dBA CNEL. Existing noise sources in La Quinta
Planning Area are generally from motor vehicle traffic, however noise is also generated from
commercial and local business operations, and construction noise.
Traffic Noise
Future noise contours have been provided along roadways throughout the Planning Area based
on build out of the General Plan Update. As shown in the tables below, traffic conditions
associated with the build out of the General Plan Update help determine the extent of future
noise impacts associated with implementation of the General Plan Update. As mentioned, most
noise in the Planning Area is associated with traffic, and level of traffic noise is based on
volumes, speed, and number of trucks in traffic. The FHWA model, used to model existing noise
contours, was applied to future Average Daily Traffic (ADT) volumes obtained from the City of
La Quinta General Plan Circulation Element Update Traffic Impact Analysis prepared by Iteris.60
The Traffic Study is further discussed in section III-O, Traffic/Circulation, and is presented in
the appendices of this EIR.
The majority of traffic in the Planning Area is made up of automobiles. Truck and bus traffic is
located along primarily along designated truck and bus routes. Future land use designations
provided by the General Plan Update continue to show General Commercial land uses along
Highway 111, which are considered non-sensitive land uses.
With the increased likelihood of more automobiles, trucks, and buses as a result of
implementation of the General Plan Update, noise levels along roadways throughout the
Planning Area will increase. Noise contours represent the distance to noise levels of a constant
value and are measured from the centerline of the roadway. Table III-33 below presents the noise
contours projected to result from build out of the proposed General Plan Update. It presents the
60 Ibid.
Terra Nova/La Quinta General Plan EIR
Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
III-153
CNEL noise contour boundaries for the 55, 60, 65 and 70 dBA noise levels, as well as a
summary of the predicted noise contours and the estimated CNEL exterior noise level at a
distance of 100 feet throughout the City.
As the Coachella Valley continues to grow, an increased regional emphasis on improving public
transit, including increased bus service, will likely occur. New SunLine bus routes will likely be
needed across the Planning Area to meet growing demands. Existing bus service is limited to the
City limit currently, including along Highway 111, Washington Street, and within the Cove.
New service will likely expand along roadways within the eastern Sphere. While additional bus
service has potential to result in noise impacts to residential development and other sensitive
receptors, these impacts are also expected to be at least partially off-set by reductions in other
vehicular traffic associated with increased use of public transportation. The City of La Quinta
will need to continue to monitor noise impacts associated with expanded and additional bus
routes and bus stops when planned near sensitive receptors.
Table III-33
Year 2035 Build Out Conditions Noise Contours
Road Segment
CNEL
at
100
Feet
(dBA)
Distance to Contour (Feet) from
centerline
70
dBA
CNEL
65
dBA
CNEL
60
dBA
CNEL
55
dBA
CNEL
Washington St. n/o Fred Waring Dr. 72.7 152 327 705 1,519
Washington St. btwn Fred Waring & Miles 73.3 165 356 766 1,650
Washington St. btwn Miles & Hwy 111 72.5 148 318 685 1,476
Washington St. btwn Hwy 111 & Avenue 48 73.0 158 341 736 1,585
Washington St. btwn Avenue 48 & Eisenhower Dr 72.3 142 306 658 1,418
Washington St. btwn Eisenhower Dr & Avenue 50 71.7 129 278 599 1,290
Washington St. btwn Avenue 50 & Calle Tampico 70.9 115 248 534 1,150
Eisenhower Dr. btwn Washington St & Avenue 50 68.1 74 160 346 745
Eisenhower Dr. btwn Avenue 50 & Calle Tampico 66.6 59 128 275 593
Avenida
Bermudas btwn Calle Tampico & Avenue 52 59.1 RW RW 87 188
Avenida
Bermudas btwn Avenue 52 & Calle Durango 63.6 RW 80 173 372
Adams St. btwn Westward Ho Dr & Hwy 111 66.6 60 129 277 597
Adams St. btwn Hwy 111 & Avenue 48 66.8 61 132 284 613
Dune Palms
Rd. btwn Westward Ho Dr & Hwy 111 65.5 50 108 232 500
Dune Palms
Rd. btwn Hwy 111 & Avenue 48 66.7 60 129 278 598
Jefferson St. n/o Fred Waring 70.4 107 230 496 1,068
Jefferson St. btwn Fred Waring & Miles 71.8 132 284 613 1,320
Jefferson St. btwn Miles & Westward Ho Dr 72.2 141 304 654 1,409
Jefferson St. btwn Westward Ho Dr & Hwy 111 72.2 140 302 651 1,402
Jefferson St. btwn Hwy 111 & Avenue 48 72.1 139 299 645 1,389
Terra Nova/La Quinta General Plan EIR
Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
III-154
Table III-33
Year 2035 Build Out Conditions Noise Contours
Road Segment
CNEL
at
100
Feet
(dBA)
Distance to Contour (Feet) from
centerline
70
dBA
CNEL
65
dBA
CNEL
60
dBA
CNEL
55
dBA
CNEL
Jefferson St. btwn Avenue 48 & Avenue 50 72.7 151 326 702 1,513
Jefferson St. btwn Avenue 50 & Avenue 52 71.1 119 256 551 1,186
Jefferson St. btwn Avenue 52 & Avenue 54 70.7 111 239 516 1,112
Madison St. btwn Avenue 50 & Avenue 52 70.4 107 231 497 1,071
Madison St. btwn Avenue 54 & Airport Blvd 72.0 136 292 629 1,355
Madison St. btwn Airport Blvd & Avenue 58 70.8 113 244 527 1,134
Madison St. btwn Avenue 58 & Avenue 60 68.2 76 164 354 762
Monroe St. btwn Avenue 52 & Avenue 54 70.4 106 228 492 1,060
Monroe St. btwn Avenue 54 & Airport Blvd 70.6 110 237 510 1,099
Jackson St. btwn Avenue 54 & Airport Blvd 70.0 101 217 467 1,006
Jackson St. btwn Airport Blvd & Avenue 58 70.2 103 221 476 1,026
Jackson St. btwn Avenue 58 & Avenue 60 69.5 93 199 429 925
Jackson St. btwn Avenue 60 & Avenue 62 68.3 77 166 358 770
Van Buren St. btwn Avenue 52 & Avenue 54 70.0 101 217 467 1,006
Van Buren St. btwn Avenue 54 & Airport Blvd 69.0 86 185 399 859
Van Buren St. btwn Airport Blvd & Avenue 58 69.3 90 195 419 904
Van Buren St. btwn Avenue 58 & Avenue 60 69.4 91 196 422 908
Van Buren St. btwn Avenue 60 & Avenue 62 65.8 52 113 243 523
Harrison St. btwn Airport Blvd & Avenue 58 73.7 176 378 815 1,756
Avenue 44 e/o Washington St 72.0 136 292 629 1,356
Miles Ave. e/o Washington St 66.6 59 127 274 590
Hwy 111 e/o Washington St 75.4 230 496 1,068 2,301
Hwy 111 e/o Adams St 74.2 191 411 885 1,906
Hwy 111 e/o Dune Palms 75.2 223 481 1,036 2,233
Avenue 48 e/o Washington St 67.0 64 137 295 635
Avenue 48 w/o Jefferson St 70.0 100 215 464 999
Avenue 50 e/o Washington St 64.4 RW 91 197 424
Avenue 50 w/o Jefferson St 67.0 63 136 294 634
Avenue 50 e/o Jefferson St 69.7 96 207 447 962
Calle Tampico
btwn Eisenhower Dr & Avenida
Bermudas 61.9 RW 62 134 289
Calle Tampico
btwn Avenida Bermudas &
Washington St 64.7 RW 95 204 440
Avenue 52 w/o Washington St 66.7 60 130 280 603
Avenue 52 w/o Jefferson St 70.1 102 220 475 1,023
Avenue 52 e/o Jefferson St 69.7 95 206 443 955
Avenue 52 e/o Madison St 69.2 88 190 410 883
Avenue 54 e/o Jefferson St 69.9 98 212 457 984
Terra Nova/La Quinta General Plan EIR
Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
III-155
Table III-33
Year 2035 Build Out Conditions Noise Contours
Road Segment
CNEL
at
100
Feet
(dBA)
Distance to Contour (Feet) from
centerline
70
dBA
CNEL
65
dBA
CNEL
60
dBA
CNEL
55
dBA
CNEL
Avenue 54 w/o Madison St 62.4 RW 67 145 312
Airport Blvd. e/o Madison St 67.3 66 141 304 656
Avenue 58 w/o Monroe St 63.8 RW 83 179 386
Avenue 58 e/o Monroe St 66.0 54 117 252 542
Avenue 60 e/o Madison St 64.9 46 99 213 460
Avenue 60 e/o Monroe St 65.3 RW 105 226 488
Avenue 62 btwn Madison St & Monroe St 64.3 42 90 195 419
Avenue 62 e/o Monroe St 67.5 68 146 314 677
Avenue 62 e/o Jackson St 63.7 RW 82 178 383
Avenue 62 e/o Van Buren St 60.1 RW 47 102 220
Source: City of La Quinta General Plan Update Noise Element Technical Report,” prepared by Urban Crossroads, Inc., June 3, 2011
1 "RW" = Location of the respective noise contour falls within the right-of-way of the road
Noise standards in La Quinta allow sensitive land uses to experience a maximum noise level of
65 dbA CNEL in outdoor living areas (patios, balconies and rear yards). Many of the roadway
segments provided in the above table exhibit future noise levels greater than 65 dBA CNEL
beyond the established right-of-way. Sensitive land uses, including residential uses, back up to
many of these roads, and may potentially experience noise levels beyond noise standards. The
noise contours provided in the above table, however, are based upon soft site conditions, and do
not account for noise barriers, topography, or final roadway grades that may affect ambient noise
levels.
Effective noise attenuation barriers can reduce noise levels by 10 to 15 decibels. In addition,
appropriate noise-compatible land use planning, such as encouraging less sensitive land uses
next to highways, has been considered and included in the Land Use Map of the General Plan.
Proper mitigation measures, including the requirement to provide walls or berms, will be
required to reduce noise levels to below 65 dBA CNEL near sensitive land uses. Noise studies
shall be required when noise-sensitive development occurs near roads and highways. With the
implementation of mitigation measures, traffic noise levels impacts in excess of local General
Plan or Noise Ordinance standards on sensitive land uses will be less than significant.
Terra Nova/La Quinta General Plan EIR
Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
III-156
Industrial and Commercial Noise
In addition to new residential development, implementation of the General Plan Update will
facilitate construction of new commercial and industrial land uses throughout the Planning Area.
Approximately 3,218,039 square feet of new commercial uses will be developed at build out in
the City Limits. Within the Sphere of Influence, new commercial and industrial uses are also
proposed at build out, including 2,458,797 square feet and 611,408 square feet, respectively.
With increased commercial and industrial development, land use compatibility issues may arise
when sensitive land uses are located adjacent to commercial/industrial areas. All land uses are
required to comply with exterior noise levels set forth in the City’s Noise Ordinance and General
Plan, as discussed above, however additional mitigation measures provided below will be required
to reduce impacts on sensitive uses. As a result, noise levels in excess of established noise standards
generated from industrial and commercial uses are expected to be less than significant with proper
mitigation.
Construction Noise
Implementation of the General Plan Update will likely increase the amount of construction
related noises associated with new development, especially within the Sphere of Influence.
Increased construction noise has the potential to increase noise levels in excess of noise
standards set by the General Plan Update or Noise Ordinance. As shown in Table III-28, the La
Quinta Municipal Code establishes base ambient noise level limits for noise sensitive and other
non-residential uses based on time of day. In addition, construction activity is limited during
established days and hours to reduce disruption of surrounding land uses. Future construction
activity will be required to abide by these standards, and as a result, will have less than
significant impacts on noise standards set by the General Plan Update and Noise Ordinance.
Impacts from Excessive Ground-borne Vibration or Ground-borne Noise Levels
As discussed above, ground-borne vibration and noise is generally associated with heavy truck and
bus traffic, as well as the use of heavy equipment at construction sites. Implementation of the
General Plan will facilitate development throughout the Planning Area, which will likely lead to
increased truck and bus traffic, as well as increased construction activity.
The increase in volume of large trucks and buses associated with new growth may potentially cause
increased vibration along designated truck and bus routes. Although the truck traffic will likely
increase along these routes, future land uses along Highway 111 and other major roadways will
remain General Commercial, which are not considered sensitive land uses. Any future truck routes
proposed throughout the Planning Area will need to consider the amount of sensitive land uses
along the proposed corridor.
Existing bus routes are currently located near sensitive land uses, such as the Cove, and new routes
may develop throughout the Planning Area, including the Sphere of Influence, as a result of new
growth caused by the General Plan Update. New bus routes may increase temporary vibration levels
for sensitive land uses. Caltrans truck traffic vibration data, however, suggests that vibrations caused
by trucks and buses diminish to below the threshold of perception at approximately 130 feet from
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the road.61 Mitigation measures associated with traffic caused vibrations are set forth below. With
implementation of these measures, excessive ground-borne vibration or noise generated from
truck and bus traffic is expected to be less than significant.
New development throughout the Planning Area will require grading, trenching and other activities
that may produce increased ground-borne vibration and noise. Construction noise is generally short
term and may be mitigated to acceptable levels by a variety of measures, including equipping
construction equipment with mufflers, locating stationary equipment away from noise sensitive
receptors and placing equipment staging areas as far from sensitive receptors as is practicable. In
addition, construction activity is required to abide by noise standards set by the General Plan
Update and Noise Ordinance. Mitigation measures for construction related vibrations are set forth
below. With implementation of these measures, impacts from excessive ground-borne vibration or
noise generated from construction activity are expected to be less than significant.
Impacts from Permanent Increase in Ambient Noise levels Above Existing Noise Levels
Permanent increases in ambient noise levels are generally associated with increased traffic in the
Planning Area. Table III-34 shows the comparison between Year 2035 CNEL contours under the
2002 General Plan at 100 feet from centerline, compared to the proposed 2035 General Plan
Update conditions. The Preferred Alternative represents 2035 conditions from implementation of
the General Plan Update. As shown below, the 2035 General Plan Update is expected to result in
both increases and decreases to noise levels compared to the 2002 General Plan conditions,
shown in the “Difference” column. Implementation of the General Plan Update will not,
however, increase noise levels perceptibly anywhere in the Planning Area.
Table III-34
Year 2035 Preferred Alternative Noise Contour Comparison
CNEL at 100 Feet (dBA) from centerline
Roadway Segment
Existing
Network
Preferred
Alternative Difference1
Washington St. n/o Fred Waring Dr. 72.7 72.7 0.1
Washington St. btwn Fred Waring & Miles 73.2 73.3 0.1
Washington St. btwn Miles & Hwy 111 72.5 72.5 0.1
Washington St. btwn Hwy 111 & Avenue 48 72.9 73.0 0.1
Washington St. btwn Avenue 48 & Eisenhower Dr 73.0 72.3 -0.7
Washington St. btwn Eisenhower Dr & Avenue 50 71.5 71.7 0.1
Washington St. btwn Avenue 50 & Calle Tampico 70.8 70.9 0.2
Eisenhower Dr. btwn Washington St & Avenue 50 68.1 68.1 0.0
Eisenhower Dr. btwn Avenue 50 & Calle Tampico 66.7 66.6 0.1
Avenida Bermudas btwn Calle Tampico & Avenue 52 59.2 59.1 0.1
Avenida Bermudas btwn Avenue 52 & Calle Durango 63.7 63.6 -0.1
Adams St. btwn Westward Ho Dr & Hwy 111 66.5 66.6 0.1
Adams St. btwn Hwy 111 & Avenue 48 66.9 66.8 -0.1
61 “City of La Quinta General Plan Update Noise Element Technical Report”, prepared by Urban Crossroads, Inc.,
June 3, 2011.
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Table III-34
Year 2035 Preferred Alternative Noise Contour Comparison
CNEL at 100 Feet (dBA) from centerline
Roadway Segment
Existing
Network
Preferred
Alternative Difference1
Dune Palms Rd. btwn Westward Ho Dr & Hwy 111 65.4 65.5 0.1
Dune Palms Rd. btwn Hwy 111 & Avenue 48 66.7 66.7 0.0
Jefferson St. n/o Fred Waring 70.4 70.4 0.0
Jefferson St. btwn Fred Waring & Miles 71.7 71.8 0.1
Jefferson St. btwn Miles & Westward Ho Dr 72.2 72.2 0.0
Jefferson St. btwn Westward Ho Dr & Hwy 111 72.2 72.2 0.0
Jefferson St. btwn Hwy 111 & Avenue 48 72.1 72.1 0.0
Jefferson St. btwn Avenue 48 & Avenue 50 72.6 72.7 0.1
Jefferson St. btwn Avenue 50 & Avenue 52 71.1 71.1 0.0
Jefferson St. btwn Avenue 52 & Avenue 54 70.6 70.7 0.1
Madison St. btwn Avenue 50 & Avenue 52 70.5 70.4 0.1
Madison St. btwn Avenue 54 & Airport Blvd 71.9 72.0 0.0
Madison St. btwn Airport Blvd & Avenue 58 70.7 70.8 0.2
Madison St. btwn Avenue 58 & Avenue 60 68.0 68.2 0.2
Monroe St. btwn Avenue 52 & Avenue 54 70.3 70.4 0.1
Monroe St. btwn Avenue 54 & Airport Blvd 70.5 70.6 0.1
Jackson St. btwn Avenue 54 & Airport Blvd 70.1 70.0 0.0
Jackson St. btwn Airport Blvd & Avenue 58 70.2 70.2 0.0
Jackson St. btwn Avenue 58 & Avenue 60 69.3 69.5 0.2
Jackson St. btwn Avenue 60 & Avenue 62 68.0 68.3 0.3
Van Buren St. btwn Avenue 52 & Avenue 54 69.8 70.0 0.3
Van Buren St. btwn Avenue 54 & Airport Blvd 69.1 69.0 -0.1
Van Buren St. btwn Airport Blvd & Avenue 58 69.4 69.3 -0.1
Van Buren St. btwn Avenue 58 & Avenue 60 69.5 69.4 0.1
Van Buren St. btwn Avenue 60 & Avenue 62 66.0 65.8 0.1
Harrison St. btwn Airport Blvd & Avenue 58 73.4 73.7 0.2
Avenue 44 e/o Washington St 71.9 72.0 0.0
Miles Ave. e/o Washington St 66.5 66.6 0.0
Hwy 111 e/o Washington St 75.5 75.4 -0.1
Hwy 111 e/o Adams St 74.3 74.2 -0.1
Hwy 111 e/o Dune Palms 75.2 75.2 0.0
Avenue 48 e/o Washington St 67.0 67.0 0.0
Avenue 48 w/o Jefferson St 70.1 70.0 -0.1
Avenue 50 e/o Washington St 64.4 64.4 0.0
Avenue 50 w/o Jefferson St 67.2 67.0 0.1
Avenue 50 e/o Jefferson St 69.6 69.7 0.1
Calle Tampico btwn Eisenhower Dr & Avenida
Bermudas 61.9 61.9 0.0
Calle Tampico btwn Avenida Bermudas & 64.7 64.7 0.0
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Table III-34
Year 2035 Preferred Alternative Noise Contour Comparison
CNEL at 100 Feet (dBA) from centerline
Roadway Segment
Existing
Network
Preferred
Alternative Difference1
Washington St
Avenue 52 w/o Washington St 66.7 66.7 0.0
Avenue 52 w/o Jefferson St 70.0 70.1 0.2
Avenue 52 e/o Jefferson St 69.7 69.7 0.0
Avenue 52 e/o Madison St 69.2 69.2 0.0
Avenue 54 e/o Jefferson St 69.8 69.9 0.1
Avenue 54 w/o Madison St 62.4 62.4 0.0
Airport Blvd. e/o Madison St 67.3 67.3 0.0
Avenue 58 w/o Monroe St 63.3 63.8 0.1
Avenue 58 e/o Monroe St 65.6 66.0 0.1
Avenue 60 e/o Madison St 63.5 64.9 1.4
Avenue 60 e/o Monroe St 65.0 65.3 0.3
Avenue 62 btwn Madison St & Monroe St 64.2 64.3 0.1
Avenue 62 e/o Monroe St 67.5 67.5 0.0
Avenue 62 e/o Jackson St 63.4 63.7 0.3
Avenue 62 e/o Van Buren St 59.9 60.1 0.3
Source: “City of La Quinta General Plan Update Noise Element Technical Report,” prepared by Urban Crossroads, Inc., June 3, 2011
1. A significant impact is considered both a level above 65 dBA CNEL and an increase greater than 3.0 dBA
Due to the logarithmic nature of traffic noise levels, a doubling of the traffic volume would result
in an increase in noise levels of 3 dBA. As discussed above, this increase is considered “barely
perceptible” based on FHWA community noise assessment criteria. Therefore, increases to noise
levels of less than or equal to 3 dBA are considered less than significant. As shown by Table
III-34, increases in noise levels throughout the Planning Area associated with the General Plan
Update are expected to be, on the average, only 0.1 dBA CNEL compared to the 2002 General
Plan conditions. Because this increase is minimal (less than 3 dBA), permanent increases in
ambient noise levels as a result of the General Plan Update are expected to be less than
significant.
Impacts from Temporary or Periodic Increases in Ambient Noise Levels Above Existing
Noise Levels
Temporary or periodic increases in ambient noise levels are generally associated with construction
activity. Implementation of the General Plan Update will facilitate new residential, commercial,
municipal, and industrial development throughout the Planning Area. Within the City,
approximately 8,114 new residential units, 3,218,039 square feet of new commercial
development, and 193.8 acres of new community facilities are expected at build out. Within the
Sphere of Influence, approximately 20,699 new residential units, 2,458,797 square feet of new
commercial space, and 611,408 square feet of new industrial uses are expected at build out.
Development of these land uses will increase the amount of construction related noise, especially
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within the Sphere of Influence. Increased construction noise has the potential to increase
temporary or periodic noise levels above existing noise levels. As mentioned above, the La
Quinta Municipal Code establishes base ambient noise level limits for noise sensitive and other
non-residential uses based on time of day. In addition, construction activity is limited during
established days and hours to reduce disruption of surrounding land uses. Future construction
activity will be required to abide by these standards, and as a result, will have less than
significant impacts on temporary noise levels.
Impacts from Airport Operations
As the population of the Coachella Valley expands, existing airport facilities will also experience
growth. The Jacqueline Cochran Regional Airport is expected to increase annual operations and
average daily takeoffs and landings. Annual operations are expected to increase from 70,000
annual operations as of 2006, 62 to 110,000 annual operations by 2025. Average flights per day
are expected to increase from 178 to 301 over the same time period. Noise generated from the
Jacqueline Cochran Regional Airport is expected to affect the eastern Sphere of Influence. The
General Plan Update proposes compatible land uses nearest the airport, including industrial and
general commercial land uses.
As shown on Exhibit III-16, future noise levels above 65 dBA CNEL will be contained within
the boundaries of the airport. Noise impacts from future aviation operations, therefore, will have
a less than significant impact on land uses proposed within the eastern Sphere of Influence.
The Bermuda Dunes Airport is a private airport located approximately 2 miles from the northern
City limits and Sphere of Influence. The airport is expected to experience an increase in annual
operations and average daily takeoffs and landings. Annual operations are expected to increase
from 42,000 annual operations in 2004 to 75,000 annual operations by 2025. Average flights per
day are also expected to increase from 115 to 205 over the same time period. Although
occasional overhead flights may occur over the northern end of the City and Sphere, future noise
levels above 65 dBA CNEL will be contained within the boundaries of the airport. No significant
impacts are anticipated to residential development or other land uses in the vicinity.
62 “Airport Operation Statistics,” Jacqueline Cochran Airport,
http://www.rcjcra.com/AirportInformation/AirportStatistics/tabid/77/Default.aspx, accessed July 12, 2011.
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Sphere of Influence
The Sphere of Influence, particularly the eastern Sphere of Influence, is expected to experience a
majority of the growth and development as a result of the implementation of the General Plan
Update. As mentioned above, approximately 20,699 new residential units are proposed at build
out in the Sphere of Influence. This will significantly increase the number of sensitive land uses
in the Sphere. The Sphere of Influence is mostly undeveloped agricultural land. Noise impacts
are expected to be primarily associated with temporary construction noises and gradually
increasing traffic volumes as these areas develop. Site-specific design features that mitigate noise
impacts may need to be implemented to limit noise impacts to acceptable levels. All noise
associated with new development in the Sphere of Influence areas will be subject to the City’s
noise ordinance and other mitigation measures described below. Without mitigation, build out of
the General Plan Update could result in significant impacts associated with noise in the Sphere.
Summary of Impacts
There are approximately 24 roadway segments in the Planning Area that currently experience
noise levels greater than 65 dBA CNEL at 100 feet from the centerline under existing conditions.
Future noise levels along roadways throughout the Planning Area are expected to increase with
implementation of the General Plan Update. Approximately 54 roadway segments are expected
to experience noise levels greater than 65 dBA CNEL at 100 feet from centerline in year 2035 at
build out of the 2002 General Plan. Implementation of the General Plan Update will only cause
one additional roadway segment (55 roadway segments in total) to experience noise levels
greater than 65 dBA CNEL at 100 feet compared to Existing Network. The greatest increase in
noise level generated by the Preferred Alternative will only cause a 1.4 dBA CNEL increase
compared to the 2002 General Plan. This small increase in noise level will be barely perceptible
to the human ear. Therefore, there will not be a substantial increase in future permanent noise
levels as a result of the General Plan Update compared to the Existing Network.
Future increases in activity associated with commercial and industrial activity, including loading
dock operations and noises associated with stationary equipment, will also likely increase
permanent noise levels. These land uses, however, are required to comply with exterior noise levels
set forth in the City’s Noise Ordinance. Additional mitigation measures provided below, such as
land use compatibility analysis, and building orientation requirements, will be required to reduce
impacts on sensitive uses. As a result, noise levels in excess of established noise s tandards generated
from industrial and commercial uses are expected to be less than significant.
The La Quinta Municipal Code establishes base ambient noise level limits for noise sensitive and
other non-residential uses based on time of day. In addition, construction activity is limited
during established days and hours to reduce disruption of surrounding land uses. Future
construction activity will be required to abide by these standards, and as a result, will have less
than significant impacts on noise standards set by the General Plan Update and Noise Ordinance.
In summary, build out of the proposed General Plan Update, including City Limit and Sphere of
Influence Planning Areas, will result in overall increases to community noise levels from
increased urbanization and associated activities including short-term construction noise,
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increases in motor vehicle traffic and other modes of transportation. These impacts may be
significant if not mitigated. Measures set forth below, however, provide broad-based mitigation
and are intended to ensure the reduction of potential noise impacts to acceptable levels.
3. Mitigation Measures
The City of La Quinta has adopted exterior noise standards in Section 9.100.210 of its Municipal
Code, which establishes base ambient noise level limits for noise sensitive and other non-
residential zones according to time of day. Municipal Code Section 9.100.220 also provides
standards for ground-borne vibrations and noises. In addition Section 6.08.050 provides limited
hours for construction to alleviate construction noise. The City’s exterior noise standards for
various land uses are consistent with those set forth by the State of California in its “Land Use
Compatibility for Community Environments” matrix.
The mitigation measures that follow shall be implemented within the General Plan area to ensure
the reduction of potential noise impacts to less than significant levels. Additional site-specific
noise mitigation measures may also be required as appropriate for future development.
General Mitigation Measures
1. The City shall continue to maintain and enforce noise standards provided by the Municipal
Code to ensure that noise impacts throughout the General Plan area are maintained at
acceptable levels.
2. The City shall continue to ensure that interior noise levels for residential development do not
exceed 45 dBA by requiring that all project designs comply with Title 25 (California Noise
Insulation Standards).
3. Acoustical studies shall be required in conjunction with entitlement applications for sensitive
receptor projects proposed adjacent to roadways shown in Table III-34. The study shall
analyze noise levels within the proposed project, and include mitigation measures to assure
that the exterior noise levels meet the City’s standards.
4. The City shall require an acoustical studies for all commercial and industrial projects that are
proposed adjacent to residential land uses or land use designations. The acoustical analysis
shall evaluate potential noise impacts of the project and provide mitigation measures that are
adequate to meet the City’s noise standards for residential land uses.
5. Sensitive receptors, which include schools, libraries and hospitals, shall, to the greatest extent
feasible, be located away from major noise generators.
Roadway Traffic Noise
6. The City shall continue to implement a planning area-wide circulation pattern that loads
primary traffic onto major arterials in order to limit local roadway traffic to the greatest
extent feasible and thereby preserve local neighborhood noise environments.
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7. The City shall evaluate and monitor noise impacts associated with the addition of new bus
routes, including bus stops near noise sensitive uses, located along collector and local roads.
8. The City shall evaluate and monitor noise impacts associated with new truck routes proposed
throughout the Planning Area, and discourage new truck routes along roadway segments near
sensitive land uses.
Construction Noise
9. All fixed and mobile construction equipment operating in the Planning Area shall be
equipped with properly operating and well-maintained mufflers to limit noise emissions.
Stationary construction equipment shall be placed away from sensitive noise receptors.
10. New construction site staging areas, stockpiling, earth moving activities, and hauling routes
should be situated away from sensitive noise land uses to the greatest extent possible.
11. All construction activities shall comply with the City of La Quinta Municipal Code Section
6.08.050.
12. Ground-borne vibration activities shall be conducted in compliance with the City of La
Quinta Municipal Code Section 9.100.220.
Stationary Noise Sources
13. Appropriate sound barriers shall surround all commercial, industrial and public facilities
located adjacent to sensitive land uses.
14. Outdoor equipment such as cooling towers, air cooled condensers and refrigeration
compressors and/or condenser units, as well as at air intake and discharge openings for
building ventilation systems, shall be provided with silencers and/or barriers at or
surrounding them, where necessary.
15. Truck deliveries to commercial and industrial areas adjacent to sensitive land uses shall be
limited to daylight hours, or shall provide noise mitigation measures to reduce noise impacts.
Mitigation Monitoring/Reporting Program
A. The City shall periodically review land-use patterns and the community noise environment,
and amend the Land Use map as appropriate to ensure reasonable land use/noise
compatibility.
Responsible Parties: Planning Department
B. The Planning Department shall review acoustical analyses for new sensitive receptor projects
located adjacent to major roadways, and commercial and industrial project located to
sensitive receptors.
Responsible Party: Planning Department
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C. The City shall work with SunLine Transit Agency to locate future bus stops and routes to
ensure noise impacts to sensitive receptors are minimized.
Responsible Party: Planning Department, SunLine Transit Agency.
Population and Housing L.
Introduction
This section of the EIR addresses potential impacts and opportunities associated with population
and housing that may exist or arise from implementation of the La Quinta General Plan Update.
The existing population and housing conditions, forecast growth and housing projections within
the City and Sphere of Influence are described, and the potential impacts relating to changes
from the previously approved General Plan, are assessed.
Thresholds of Significance/Criteria for Determining Significance
The following thresholds or criteria are derived from Appendix G of the CEQA Guidelines, and
are used to determine the level of potential effect. The significance determination is based on the
recommended criteria set forth in Section 15064 of the CEQA Guidelines. For analysis purposes,
build out of the La Quinta General Plan would have a significant effect on population and
housing if it is determined that the project will:
a.) Induce substantial population growth in an area, either directly (for example, by
proposing new homes and businesses) or indirectly (for example, through extension of
roads or other infrastructure).
1. Existing Conditions
The General Plan Update Planning Area consists of the incorporated City limits and the
unincorporated Sphere of Influence. Residential development within City limits is 73% built out,
whereas residential development within the Sphere of Influence is 7.5 % built out.
Demographic Information
Population
In 2000, there were 23,694 people living in La Quinta. The 2010 U.S. Census reports a
population size of 37,467 for the City of La Quinta. In 2000, the median age was 36.4 years,
while in 2010 the median age was 46.6. According to the 2010 U.S. Census, the population of La
Quinta is 63.1% White, 30.3% Hispanics, 3.1% Asian, 1.9% Black or African American, and
1.6% other. Approximately 36.3% of the population within the City of La Quinta is above 55
years of age.63
Currently, there are approximately 23,489 dwelling units within the City, 14,820 of which are
occupied. Assuming an average household population size of 2.53 and full occupancy of all
63 Profile of General Population and Housing Characteristics, for the City of La Quinta, 2010 US Census.
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existing dwelling units, the existing population in La Quinta’s City limits is estimated to be
59,427.
In the Sphere of Influence, under Riverside County’s land use designations, there are
approximately 7,173 acres of residentially designated lands, of which 538 acres are currently
developed. According to Riverside County, the developed acreage contains an estimated 801
existing low density residential dwelling units. Based on the persons per household figure of
2.53, the existing population within the Sphere of Influence is estimated to be 2,027.
In total, the General Plan Update Planning Area is estimated to contain an existing population of
61,454.
Housing Units
In 2000, there were 11,812 housing units within the City of La Quinta, and by 2005, there were
18,762 dwelling units. The 2010 Census accounted for a total of 23,489 dwelling units, the
majority of which are single family detached units -- approximately 80% of the housing stock is
single family detached, 10% is single family attached, 9% is multi-family, and 1% is mobile
homes.64 Nearly 37% of all housing units are unoccupied. The 2010 population of 37,467 and the
14,820 occupied dwelling units yields an average household population size of 2.53 persons per
household.
It should be noted many of La Quinta homeowners are second homeowners and are considered
part-time residents. According to the 2010 U.S. Census, approximately 27.5% of La Quinta
dwelling units were vacant due to seasonal, recreational, or occasional use.
In the second quarter of 2011 the median home price for existing homes in La Quinta was
$232,000 and the median new home price was $360,000.65 At current levels, home ownership is
considered affordable to moderate income households. Home prices exceed those of Riverside
County for the same period, which were $189,000 for existing homes and $290,000 for new
homes.
Employment
In 2007, there were 14,918 jobs within the City. Based on the 2009 Riverside County progress
report, La Quinta’s civilian labor force was comprised of 14,700 persons, with 13,700 employed
and 1,100 unemployed. The majority of jobs within City limits are in the resort, service, and
hospitality industry, followed by retail trade, professional and business services, and
construction. The median household income in La Quinta in 2000 was $54,552, and had risen to
$78,898 by 2010.
2. Project Impacts
There are 23,489 dwelling units within City limits, and 801 units within the Sphere of Influence,
for a total of 24,290 existing dwelling units throughout the Planning Area. The General Plan
64 Average Housing Characteristics for 2005-2009, prepared by the American Community Survey. 65 “Inland Empire Quarterly Economic Report,” prepared by John E. Husing, Ph.D., October 2011.
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Update allows for a total of up to 31,603 residential dwelling units within City limits and 21,500
dwelling units within the Sphere of Influence, which has the potential to result in a total of
53,103 dwelling units throughout the Planning Area. Development of these residential units
could support an additional 72,897 residents beyond the existing population of 61,454, which
would result in a build out population of 134,352 in the General Plan Update Planning Area. It
should be noted that these figures assume an average household population size of 2.53 people
and full occupancy of seasonal, recreational, and occasional occupancy dwelling units, as well as
permanent residency.
La Quinta City Limits
Within the La Quinta City limits, build out of the proposed General Plan Update has the potential
to result in the development of an additional 8,114 dwelling units, which could support an
additional 20,528 people, assuming an average household occupancy of 2.53. At General Plan
build out, the population size within city limits is projected to be 79,956, based on full
occupancy of the 31,603 dwelling units that are proposed under the General Plan Update. This
represents a 34% increase over the existing number of dwelling units and the associated
population size.
According to the Southern California Association of Government’s (SCAG) May 2011 growth
forecasts, it is projected that by 2035 La Quinta’s permanent population will be 46,297 people,
and there will be 17,948 occupied dwelling units within the City of La Quinta. SCAG projections
assume an annual growth rate of approximately 0.85%. These projections do not account for
seasonal, recreational, and occasional occupancy. As such, to determine consistency with the
SCAG forecasts, projections set forth in the La Quinta General Plan are discounted by 27.5%.
Discounting the proposed General Plan projections by 27.5% yields an estimated 22,912
dwelling units and an associated population of 57,969 in 2035, which assumes an annual growth
rate of 1.38%. Projections set forth in the La Quinta General Plan are approximately 20% greater
than the SCAG forecast in 2035. This difference is expected given the variation in growth rates,
and the conservative assumptions of the EIR analysis including full occupancy of seasonal units
and a build out year of 2035.
Assuming that the proposed General Plan Update builds out by 2035, the population would have
increased by 34% compared to the 2010 population. As such, the General Plan Update has the
potential to induce population growth. Given that this rate of growth is estimated to be 1.38% per
year, the proposed General Plan is not expected to be substantially growth inducing.
When considering the entire Planning Area, the build out population under the General Plan
Update is reduced compared to the 2002 General Plan (See Planning Area discussion below).
Therefore, although the proposed General Plan has the potential to increase the population and
housing development within city limits, it is not expected to result in significant growth inducing
impacts.
The General Plan Update would allow for the development of an additional 3,218,039 square
feet of commercial development within City limits. While it is difficult to estimate the exact
number of jobs that may be created as a result of this development, the Riverside County Center
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for Demographic Research projects that, by 2035, there will be a total of 21,678 jobs within La
Quinta City limits. The 2002 General Plan allowed for up to 7,899,431 square feet of commercial
development within city limits at built out. The level of commercial development proposed under
the General Plan Update is a reduction from the commercial development proposed under the
2002 General Plan. Therefore, the General Plan Update will not induce growth as a result of
commercial or business development and impacts are considered to be less than significant.
Employment Projections
According to the SCAG Integrated Growth Forecast, it is projected that in 2020 there will be
10,565 La Quinta residents that are employed, and by 2035, there will be 11,864 La Quinta
residents who are employed. The City of La Quinta is projected to contain 21,678 jobs by 2035.
As such, over half of the jobs offered in La Quinta City limits could be filled by La Quinta
residents.
Sphere of Influence
In the Sphere of Influence, under the County’s land use designation, there are approximately
7,175 acres of residentially designated lands. If the Sphere were to build out under the current
County land use designations, a total of 11,946 residential units would be developed. Based on
the persons per household rate of 2.53, the population within the Sphere of Influence would be
30,222.
For purposes of analysis, this document assumes build out of the Sphere under the designations
assigned to these lands on the Land Use Map. However, the General Plan Update requires the
completion of a master plan for the eastern Sphere, which could significantly change the number
of units that are developed in this area. The General Plan Update allows for the development of
up to 21,500 residential dwelling units, which would result in a built out population size of
54,396 within the Sphere of Influence. As proposed, implementation of the General Plan Update
would increase the population within the Sphere of Influence by 24,174 people or 80% over the
current County land use designations. Therefore, the General Plan Update has the potential to
induce growth and result in a substantial increase to the population size. The proposed
development for residential land uses in the Sphere of Influence has the potential to result in
significant impacts to population and housing. The development of the master plan for the area
will change the land use distribution in this area, and provide greater specificity regarding
building density and intensity. The master plan, therefore, will mitigate potential impacts
associated with population and induced growth.
In addition, the General Plan Update would allow for the development of up to 2,732,557 square
feet of commercial development and 611,408 square feet of industrial uses within the City’s
Sphere of Influence. Under the General Plan Update, all land outside of the incorporated city
limits are contained within the Sphere of Influence, and said area, including proposed square
footage, has been reduced compared to the 2002 General Plan.
Under the County’s Vista Santa Rosa Land Use Concept Plan, a total of 5,161,764 square feet of
retail is proposed. The proposed General Plan Update would result in less commercial
development relative to the 2002 General Plan and the County’s Plan. Therefore, commercial
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development set forth in the General Plan Update is not expected to be growth inducing, and
impacts will be less than significant.
Planning Area Summary
The overall Planning Area for the La Quinta General Plan Update has the potential to result in
the development of 53,103 residential units, which could support a population of 134,352 people.
As described above, implementation of the General Plan Update is not expected to substantially
induce growth within City limits. However, the proposed development within the Sphere of
influence has the potential to increase the population by 80% compared with that permitted under
current County land use designations. Thus, the proposed General Plan Update has the potential
to result in significant impacts to population and housing from growth inducing development
within the Sphere of Influence. In order to mitigate potential impacts from proposed
development within the Sphere of Influence, a Master Plan of Development will be prepared.
Adherence to such a plan would be sufficient to reduce potential impacts to population and
housing within the Sphere of Influence to levels below significance.
3. Mitigation Measures
1. A Master Plan of Development shall be prepared for the Vista Santa Rosa area. Development
within this area shall be subject to policies set forth in the said Master Plan.
Monitoring and Reporting
A. New development proposed for the Sphere of Influence will be reviewed for consistency
with the Master Plan of Development.
Responsible Parties: Planning Department
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Public Services & Utilities M.
Introduction
Current public services, utilities and service systems in the General Plan Planning Area and the
vicinity are described in this section. It also analyzes potential constraints, risks and
opportunities associated with these existing conditions. Potential impacts associated with
implementation of the proposed General Plan Update are also considered, and mitigation
measures set forth to reduce impacts.
In order to research and assess these impacts, a variety of resources have been consulted,
including personal communication with service providers and other sources. Please also see
Existing Conditions, below, for further discussion of these resources.
Thresholds of Significance/Criteria For Determining Significance
The following standards and criteria have been drawn from Appendix G Environmental
Checklist Form of the CEQA Guidelines to assess the significance of potential impacts to public
services and facilities that may result from the adoption and implementation development of the
La Quinta General Plan. Impacts would be considered significant if implementation of the
General Plan would result in the following:
a.) Conflict with or obstruct construction of new public utilities or facilities, including
above-ground and subsurface energy, fuel or telecommunication transmission facilities.
b.) Conflict with or obstruct the operation and maintenance of existing public utilities or
facilities, including aboveground and subsurface energy, fuel or telecommunication
transmission facilities.
c.) Result in substantial adverse physical impacts associated with or create substantial
impediments to the provision of new or physically altered government facilities.
d.) Exceed wastewater treatment requirements of the applicable Regional Water Quality
Control Board.
e.) Require or result in the construction of new or wastewater drainage facilities or
expansion of existing facilities, the construction of which could cause significant
environmental effects.
f.) Require or result in the construction of new stormwater drainage facilities or expansion
of existing facilities, the construction of which could cause significant environmental
effects.
g.) Not have sufficient water supplies available to serve the project from existing
entitlements and resources, or new expanded entitlements are needed.
h.) Have inadequate landfill capacity to accommodate the project’s solid waste disposal
needs.
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i.) Fail to meet the water supply assessment requirements of Water Code Section 10910, et
seq. (SB 610), and the requirements of Government Code Section 664737 (SB 221).
j.) Fail to result in a determination by the wastewater treatment provider which serves or
may serve the project that it has adequate capacity to serve the project’s projected
demand in addition to the provider’s existing commitments.
k.) Not be served by a landfill with sufficient permitted capacity to accommodate the
project’s solid waste disposal needs.
l.) Fail to comply with federal, state, and local statues and regulations related to solid waste.
m.) Result in substantial adverse physical impacts associated with the provision of new or
physically altered governmental facilities, or create a need for new or physically altered
governmental facilities, the construction of which could cause significant environmental
impacts, in order to maintain acceptable service ratios, response time or other
performance objectives for fire protection, police protection, schools, parks, and other
public facilities.
Service Providers
There are a wide range of public services and facilities serving the General Plan Update area.
These include:
Public Schools: Desert Sands Unified School District, Coachella Valley Unified School
District
Library Services: Riverside County Library System
Law Enforcement: La Quinta Police Department/Riverside County Sheriff’s Department
Fire Protection: La Quinta Fire Department
Electricity: Imperial Irrigation District
Natural Gas: The Gas Company
Domestic Water: Coachella Valley Water District
Wastewater Collection/Treatment: Coachella Valley Water District
Solid Waste Management: Burrtec Waste and Recycling Services, LLC
Schools
1. Existing Conditions
Public Schools
There are two school districts providing public education to students in Kindergarten through
12th Grade in La Quinta: Desert Sands Unified School District (DSUSD) and Coachella Valley
Unified School District (CVUSD). Each is described below.
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Desert Sands Unified School District
DSUSD services students to students living west of Jefferson Street and north of Avenue 48.
This includes the northern Sphere of Influence. District administrative offices and the bus yard
are located on Dune Palms Road in La Quinta.
There are seven DSUSD schools in La Quinta. The following table lists each school as well as
enrollment and design capacity.
Table III-35
Desert Sands Unified School District Enrollment and Capacity
School Location
2010
Enrollment1 Capacity2
John Adams Elementary School 50-800 Desert Club Drive 432 750
Benjamin Franklin Elementary School 77-800 Calle Tampico 631 750
Harry S. Truman Elementary School 78-870 Avenue 50 614 750
La Quinta Middle School 78-900 Avenue 50 662 1,200
Colonel Mitchell Paige Middle School 43-495 Palm Royale Drive 993 1,200
La Quinta High School 79-255 Westward Ho Drive 2,948 2,200
Summit Continuation School (K-12) 43-330 Palm Royale Drive 475 N/A
1 Enrollment as of November, 2010. Source: Personal communication, Linda Lawson, DSUSD Fiscal Department,
December 16, 2010. 2 Represents design capacity; school facility capacities expand to meet enrollment using portable classrooms.
Source: Personal Communication, James Kozero, DSUSD Facilities Department, December 16, 2010.
As noted above, current enrollment at the La Quinta High School exceeds design capacity. The
District utilizes portable classrooms to accommodate over-capacity student enrollment at its
schools until enrollment warrants construction of new school facilities. DSUSD recently opened
the Shadow Hills High School north of US I-10 near Jefferson Street, which it expects will
gradually absorb some of the excess student population currently served by La Quinta High
School. Shadow Hills has a current enrollment of between 900 and 1,000 students.
In general, DSUSD student populations have remained stable or declined slightly as a result of
recession-related impacts on local development. Facilities staff has indicated it expects that no
new school facilities will be required in the short term (2 to 4 years). However, the District
continues to plan for expansion. Although there are few if any sites available for new DSUSD
school facilities within La Quinta, DSUSD has identified future school site properties near the
Shadow Hills campus and in the cities of Indio and Coachella.66
Coachella Valley Unified School District
The CVUSD district boundaries within La Quinta include lands east of Jefferson Street and East
of Avenue 48. This includes the City’s eastern Sphere of Influence. There are four CVUSD
schools serving students in La Quinta and the eastern Sphere. These are shown in Table III-36.
66 Personal communication, James Kozero, Project Manager, DSUSD Facilities Department, December 16, 2010.
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Table III-36
Coachella Valley Unified School District Enrollment and Capacity
School Location
2010
Enrollment1 Capacity
Westside Elementary School 82-225 Airport Boulevard (Sphere) 636 678
Cahuilla Desert Academy 82-489 Avenue 52 (Sphere) 721 990
Mountain Vista Elementary School 49-750 Hjorth Street (NE of Sphere) 991 750
Coachella Valley High School 83-800 Airport Boulevard (City limits) 2,551 1,712
1 Enrollment as of December, 2010.
Source: Personal communication, Marcella Valdez, CVUSD Facilities Department, December 16, 2010.
The over-capacity student population at Mountain Vista Elementary School is currently housed
in portable classrooms. The District has no plans for a new elementary school; however, a new
school to serve students grades 7 through 12 is planned near Avenue 49 and Monroe Street, east
of the City. No construction start date has been specified.67
Other Public School Facilities
DSUSD also provides adult education programs, such as GED test preparation, citizenship
classes and English as a Second Language. It also offers early childhood education, special
education services, and after-school programs. The Alternative school provides independent
learning and home schooling support for students in grades Kindergarten through 12th grade.
Other CVUSD services include an adult school with vocational training, citizenship classes, and
GED test preparation. CVUSD also offers tutoring and special education services.
School Funding
There are a variety of funding sources for these school districts, including a portion of local
property taxes as well as State funds. In addition, State Assembly Bill 2926 (AB 2926), enacted
in 1986) authorizes school districts to levy an impact fee on developers. These fees may be used
to construct new facilities. They are updated periodically. Fees are $2.97 per square foot of new
residential development and $0.47 per square foot of commercial/industrial development.68
Higher Education Institutions
There are three regional higher education institutions in the eastern Valley. They include the
College of the Desert, a community college with Associates degree programs and adult
education. Bachelor’s and Master’s degree programs are offered through California State
University, San Bernardino and University of California, Riverside. All three campuses are
located in Palm Desert, approximately 8 miles northwest of the City.
67 Personal communication, Marcella Valdez, CVUSD Facilities Department, December 16, 2010. 68 “Facilities: Demographics,” http://www.coachella.k12.ca.us/interport/default.aspx?tabid=59, accessed
November 23, 2010.
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2. Impacts
The following tables show estimated student enrollment in the City limits and Sphere of
Influence. These estimates include existing and future units based on General Plan build out.
Table III-37
Potential Student Generation La Quinta City Limits
Grade Level Max. Student Projected
Enrollment Build out Units Generation Rate
Elementary (K-6)
Single Family 25,585 0.214 5,475
Multi-Family 6,017 0.1267 762
Elementary Subtotal 6,237
Middle (7-8)
Single Family 25,585 0.1093 2,796
Multi- Family 6,017 0.0522 314
Middle School Subtotal 3,110
High School (9-12)
Single Family 25,585 0.1427 3,651
Multi-Family 6,017 0.0543 327
High School Subtotal 3,978
Total 31,603 13,325
Terra Nova Staff Estimates based on Student Generation Rates, Desert Sands Unified School District
Master Facilities Plan, October 2008.
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Table III-38
Potential Student Generation Sphere of Influence
Grade Level Max. Student Projected
Enrollment Build out Units Generation Rate
Elementary (K-6)
Single Family 21,281 0.214 4,554
Multi-Family 219 0.1267 28
Elementary Subtotal 4,582
Middle (7-8)
Single Family 21,281 0.1093 2,326
Multi- Family 219 0.0522 11
Middle School
Subtotal
2,337
High School (9-12)
Single Family 21,281 0.1427 3,037
Multi-Family 219 0.0543 12
High School Subtotal 3,049
Total 21,500 9,968
Terra Nova Staff Estimates based on Student Generation Rates, Desert Sands Unified School District
Master Facilities Plan, October 2008.
Table III-39
Potential Student Generation Planning Area Summary
Grade Level Max.
Build out Units
Student
Generation Rate
Projected
Enrollment
Elementary (K-6)
Single Family 46,866 0.214 10,029
Multi-Family 6,236 0.1267 790
Elementary Subtotal 10,819
Middle (7-8)
Single Family 46,866 0.1093 5,122
Multi- Family 6,236 0.0522 325
Middle School Subtotal 5,447
High School (9-12)
Single Family 46,866 0.1427 6,688
Multi-Family 6,236 0.0543 339
High School Subtotal 7,027
Total 53,103 23,293
Terra Nova Staff Estimates based on Student Generation Rates, Desert Sands Unified School District
Master Facilities Plan, October 2008.
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New development in the planning area will occur over time, and student populations are also
expected to increase gradually. Both school districts employ facilities planning that provides for
new school sites as population within their respective boundaries increases. CVUSD and
DSUSD will continue to receive developer’s impacts fees for residential, commercial and
industrial development. These measures are expected to minimize impacts to CVUSD and
DSUSD schools. However, schools in both districts are currently operating at or beyond
capacity, and new facilities will be needed to serve the build out student population in the
Planning Area. Mitigation measures are set forth below to ensure that any potential adverse
effects to public schools are reduced to less than significant levels.
At this level of analysis, there is not sufficient site-specific development data to calculate
developer impact fees; further these fees are periodically adjusted. It is to be expected, however,
that these fees will be substantial and will assist the school districts in the General Plan Area to
offset impacts of new development on their respective schools.
3. Mitigation Measures
The following mitigation measures shall be implemented to ensure that impacts are reduced to
less than significant levels for schools in the Coachella Valley Unified School District and Desert
Sands Unified School District.
1. Developers shall continue to be assessed statutory school mitigation fees for residential and
commercial development.
Mitigation Monitoring and Reporting
A. The City shall continue to coordinate with the Coachella Valley Unified School District and
Desert Sands Unified School District to assure that statuary developer impact fees are
collected.
Responsible Party: Planning Department
Libraries
1. Existing Conditions
The La Quinta Library is located at 78-275 Calle Tampico. The City owns the library facility,
which is operated by Riverside County. Currently, the Library contains 89,060 volumes within a
20,000 square foot space. Although the City has not established a standard for library facilities,
the County Library system aims for an un-adopted standard of two volumes per capita. Based on
this standard, existing library facilities are sufficient to serve the current population.
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2. Impacts
Based on the County Library System’s target standard, the estimated build out population of
79,956 in the City limits will require 159,912 volumes at build out of the General Plan. The
Sphere build out population of 54,396 will require 108,792 volumes. In total, the Planning Area
will require 268,704 volumes at build out. Additional facilities would also likely be required to
house the additional volumes and serve patrons.
The City assesses Developer Impact Fees (DIF) on residential development for library services
and facilities. Currently, fees are assessed at $355 for single-family detached units, $266 for
single-family attached units, and $348 for multi-family units.69 These are one-time fees assessed
when new units are constructed. Based on these fees, new residential development in the City
limits could generate up to approximately $2.86 million in library fees; up to an additional $7.35
million could be generated in the Sphere. In total, new residential development in the planning
area is expected to generate approximately $10.21 million in library development fees. Fees will
be assessed as new development occurs, so these revenues will not be available to the City all at
one time. The City’s DIF schedule would be expected to increase over the course of General
Plan build out. These fees have been developed based on a rational nexus, and will therefore be
sufficient to accommodate growth through General Plan build out, reducing impacts to less than
significant levels.
The City has studied the land use pattern in the Sphere, and has considered several potential
annexation proposals in the past. These proposals included analyses relating to the availability
and cost of the provision of services in the Sphere. These analyses found that in the eastern
Sphere in particular, lands have been encumbered by the County as collateral for a regional bond
issue. As a result, there will be no property tax generation to the City from these lands for a
number of years. The fiscal analysis concluded that the annexation of property in the Sphere
would have a negative fiscal impact on the City. At the time of the analysis, a per unit mitigation
fee was considered, but the proposed annexations did not proceed, and the mitigation program
was not implemented. The costs associated with annexation to the City, however, still exists, and
will remain an issue as annexation proposals occur in the future.
As described above, the annexation of lands in the eastern Sphere would have a negative fiscal
impact on the City, including the library. Although past annexation requests were not completed,
conditions have not changed since this analysis was undertaken, and it would be expected that
annexation proposals in the future would have a similarly negative fiscal impact. The General
Plan includes policies that require both the preparation of fiscal impact analyses for annexation
proposals, and a Development Agreement in association with annexation. The Development
Agreement would establish the parameters for development, and would include mitigation fee
payments for projects that are fiscally negative for the City. These Development Agreements
would eliminate the potential fiscal impacts to the City in providing library services to newly
annexed lands.
The implementation of these policies would reduce impacts to less than significant levels.
69 “City of La Quinta Development Impact Fee Summary,” December 8, 2008.
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3. Mitigation
None required.
Mitigation Monitoring and Reporting
None required.
Law Enforcement
1. Existing Conditions
The City contracts annually with the County of Riverside for police staffing. In 2010-2011, the
City’s contract provided for the equivalent of 51 sworn officers and 5 community service
officers. City-assigned officers conduct investigations, manage traffic control, and provide
general patrol duties. Patrol division staff is augmented by a Special Enforcement Team, which
provides investigative services and support for prevention activities in the community.
Community programs include the School Resource Officer program at local schools; the Junior
Cadet program; a Crime Stoppers program; the volunteer Citizens on Patrol Program; and
Community Service Officers. The latter, which are assigned to each division, serve as
community liaisons and are responsible for coordinating Community Programs such as
Neighborhood Watch.
There are two Police Department offices in the City: a station at 51-351 Avenida Bermudas, and
a Business District Office located at 79-440 Corporate Center Drive.
The Riverside County Sheriff’s Department maintains a staffing level of one staff per 1,000
population.70 The City has no established staffing ratio, and police staffing in La Quinta is based
on the safety needs of the local community and the available resources to provide these safety
needs.71 Based on the City’s 2010 full occupancy population of 59,427, the current level of
police staffing is approximately 1.06 staff per 1,000 population.
70 Written communication, Lt. Jason Huskey, Assistant Police Chief, La Quinta Police Department, Riverside
County Sheriff’s Department, December 2, 2010. 71 Written communication, Bret Plumlee, Assistant City Manager, City of La Quinta, December 6, 2010.
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2. Impacts
At build out, the City and Sphere of Influence are expected to have a total population of 134,352.
Based on the Riverside County staffing ratio, the police department will require 134 sworn
officers at build out. This is an increase of 78 sworn officers as compared with current staffing
levels, which represents a substantial additional demand for police protection and associated
equipment and patrol vehicles. Increases in cost to the City could be significant. Demand will
increase gradually, and revenues to the City are also expected to occur as the General Plan builds
out. Demand for police protection will depend on actual development in the future.
The City has studied the land use pattern in the Sphere, and has considered several potential
annexation proposals in the past. These proposals included analyses relating to the availability
and cost of the provision of services in the Sphere. These analyses found that in the eastern
Sphere in particular, lands have been encumbered by the County as collateral for a regional bond
issue. As a result, there will be no property tax generation to the City from these lands for a
number of years. The fiscal analysis concluded that the annexation of property in the Sphere
would have a negative fiscal impact on the City. At the time of the analysis, a per unit mitigation
fee was considered, but the proposed annexations did not proceed, and the mitigation program
was not implemented. The costs associated with annexation to the City, however, still exists, and
will remain an issue as annexation proposals occur in the future.
As described above, the annexation of lands in the eastern Sphere would have a negative fiscal
impact on the City, including police services. Although past annexation requests were not
completed, conditions have not changed since this analysis was undertaken, and it would be
expected that annexation proposals in the future would have a similarly negative fiscal impact.
The General Plan includes policies that require both the preparation of fiscal impact analyses for
annexation proposals, and a Development Agreement in association with annexation. The
Development Agreement would establish the parameters for development, and would include
mitigation fee payments for projects that are fiscally negative for the City. These Development
Agreements would eliminate the potential fiscal impacts to the City in providing police services
to newly annexed lands.
The implementation of these policies would help to reduce impacts.
3. Mitigation
1. All new development projects shall be subject to Police Department review to assure that the
Department can provide adequate police protection.
2. The City shall monitor City population and Police Department staffing levels to ensure the
provision of police protection services at sufficient levels.
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Mitigation Monitoring and Reporting
A. On an annual basis, the City shall evaluate response times and police activity to assure
adequate protection.
Responsible Parties: City Manager, Police Department.
Fire Protection
1. Existing Conditions
Fire protection is provided through a contract with the Riverside County Fire Department, which
also serves the Sphere of Influence areas. There are three City-owned fire stations, each staffed
with full-time paid and volunteer firefighters, and equipped as listed below:
Fire Station No. 32 at 78-111 Avenue 52; equipment includes a primary and reserve fire engines,
and volunteer squad and rescue vehicles.
Fire Station No. 70 at 54001 Madison Street; equipped with a primary engine, a brush fire
engine, and a volunteer squad vehicle.
Fire Station No. 93 at 44-555 Adams Street; equipped with a primary engine and a reserve
engine.
Emergency response in the Planning Area is also available through Riverside County Fire
Department stations in other cities. These include Station No. 55, located in Indian Wells;
Station No. 88, in Indio; and Station No. 39, located at the Desert Resorts Airport, east of the
City’s eastern Sphere of Influence. County Fire dispatches all calls through its centralized
Emergency Command Center, where responding stations are determined based on location and
need.
Average Fire Department response times are between 5 and 7 minutes. La Quinta has an
Insurance Service Office (ISO) of 4, based on a scale of 1 through 10, with 1 being the highest
rating. Ratings are reviewed periodically. A variety of criteria are used to determine the ISO
rating, such as staffing levels, response times, safety history and building code standards.
The County Fire Department cites thresholds established in its 1986 Master Plan,72 which call for
one new fire station per every 2,000 dwelling units or 3.5 million square feet of commercial
development.73 The Fire Department has developed a Strategic Plan to update thresholds and
plan for staffing, facilities and services through 2029. Goals and strategies include developing a
“standard of cover” analysis to establish appropriate staffing levels to meet operational needs
within the various jurisdictions the Department serves.74
72 “Riverside County Fire Protection and Emergency Medical Master Plan”, January 2, 1986. 73 Personal communication, Jason Newman, Riverside County Fire Department Strategic Planning, December 22,
2010. 74 “Riverside County Fire Department Strategic Plan 2009-2029”, prepared by Management Partners, Inc.,
November 2009.
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2. Impacts
Implementation of the General Plan Update and the increase in population in the General Plan
Planning Area is expected to result in an increase in demand for fire protection services. The
need for additional services will be determined as the Planning Area develops; additional staff,
equipment and vehicles, and fire stations will be needed. The extension of water mains and
installation of new fire hydrants may also be required which are currently undeveloped or less
developed. The potential cost to the City may be substantial, and on-going monitoring and
evaluation of the need for additional facilities and staff will be necessary throughout build out.
The County Fire Department evaluates specific development proposals based on their potential
to demand additional fire department facilities and staffing. It considers existing conditions in the
area as well as future needs of such new development in determining whether it is appropriate to
require new fire facilities based on the standards set forth in the 1986 Master Plan, as cited
above.75 It is expected that as the General Plan Area builds out, new “standards of cover”
developed in association with the Department’s Strategic Plan will be applied to new
development. Future development will continue to be subject to Fire Department review and new
fire facilities will be constructed as needed to ensure adequate provision of fire protection
services in the Planning Area.
The City has studied the land use pattern in the Sphere, and has considered several potential
annexation proposals in the past. These proposals included analyses relating to the availability
and cost of the provision of services in the Sphere. These analyses found that in the eastern
Sphere in particular, lands have been encumbered by the County as collateral for a regional bond
issue. As a result, there will be no property tax generation to the City from these lands for a
number of years. The fiscal analysis concluded that the annexation of property in the Sphere
would have a negative fiscal impact on the City. At the time of the analysis, a per unit mitigation
fee was considered, but the proposed annexations did not proceed, and the mitigation program
was not implemented. The costs associated with annexation to the City, however, still exists, and
will remain an issue as annexation proposals occur in the future.
As described above, the annexation of lands in the eastern Sphere would have a negative fiscal
impact on the City, including fire protection services. Although past annexation requests were
not completed, conditions have not changed since this analysis was undertaken, and it would be
expected that annexation proposals in the future would have a similarly negative fiscal impact.
The General Plan includes policies that require both the preparation of fiscal impact analyses for
annexation proposals, and a Development Agreement in association with annexation. The
Development Agreement would establish the parameters for development, and would include
mitigation fee payments for projects that are fiscally negative for the City. These Development
Agreements would eliminate the potential fiscal impacts to the City in providing fire protection
services to newly annexed lands.
75 Personal communication, Jason Newman, Riverside County Fire Department Strategic Planning, December 22,
2010.
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The implementation of these policies would help to reduce impacts.
3. Mitigation
Impacts associated with provision of fire protection services will be reduced to less than
significant levels with the implementation of the following mitigation measures:
1. The City and Riverside County Fire Department shall continue to confer and coordinate to
ensure that facilities and services are expanded in a timely manner.
2. The City shall plan for siting of industrial facilities that store hazardous, flammable or
explosive materials so as to assure the highest level of safety in strict conformance with
Uniform Fire Code and other applicable codes and regulations.
3. The Riverside County Fire Department shall continue to review and evaluate new
development proposals and project plans to make certain that it can provide adequate fire
protection.
Mitigation Monitoring and Reporting
A. Riverside County Fire Department shall review all development plans prior to issuance of
building permits to ensure that development complies with City and Fire Department
standards.
Responsible Parties: Planning Department, Riverside County Fire Department
Electricity
1. Existing Conditions
Imperial Irrigation District (IID) provides electric power in the City and the Sphere of Influence.
IID delivers electric service by means of power generation and contractual agreements. There are
six IID substations within or near the Planning Area, as follows:76
North La Quinta Substation – northwest corner of Adams Street and Westward Ho;
La Quinta Substation – southwest corner of Avenue 48 and Jefferson Street;
Jefferson Substation – Jefferson Street at the northeast corner of Avenue 52;
Marshall Substation – northeast corner of Washington Street and Avenida Ultimo;
Avenue 58 Substation – northwest corner of Avenue 58 and Monroe Street;
Thermal Substation – south of Airport Boulevard and east of Highway 111.
Substations are gauged at 92 or 161 kilovolts (kV), and from there electrical power is decreased
for distribution to customers at 12.47 kV. There are 8 proposed substations in the Planning Area
and vicinity. Of these, one was discussed in the previous General Plan update between the
76 Written communication provided by Guillermo Barraza, Customer Operations and Planning, Imperial Irrigation
District, December 21, 2010.
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easterly Sphere boundaries and the Jacqueline Cochran Regional Airport. This substation is still
in the planning stages. Other proposed substation locations include:77
Near Avenue 54 and Monroe Street;
At Van Buren Street and Avenue 64;
Near Avenue 60 and Monroe Street;
At Avenue 58 and Harrison Street;
At Madison Ave and Avenue 64;
At 54 and Harrison Street;
At Avenue 62 and Harrison Street.
The City’s Municipal Code (Chapter 13.24.110) requires that all utilities in new residential
districts and subdivisions be undergrounded.
Based on historical use data for the Planning Area provided by IID, it was estimated that
residential development consumes approximately 16,798 kilowatt hours per year. Estimated
electricity usage rates by land use type are shown in Table III-40.
Table III-40
Estimated Electricity Usage Rates
Land Use Annual Usage Rate
Residential 16,798 Kilowatt-hour/unit/year
Commercial 57.88 Kilowatt-hour/square feet/year
Industrial 57.88 Kilowatt-hour/square feet/year
Source: Terra Nova Staff estimates based on 2005 demand data for Planning Area
provided by Hugo Valdez, Imperial Irrigation District, October 22, 2010.
Based on these factors, existing residential and commercial development in the City consumed
an estimated 765,590,714 kilowatt hours, while residents and commercial users in the Sphere
consumed 29,242,547 kilowatt hours.
2. Impacts
Estimates of annual electrical demand for General Plan build out are based on the annual usage
rates shown above. These rates applied to the proposed General Plan land uses at build out will
result in electrical consumption of 1,645,145,600 kilowatt-hours per year (kwh/year). Single-
family residential uses will account for 791,924,912 kwh/year of this amount, while multi-family
uses will account for 101,224,748 kwh/year. Commercial uses will consume 716,607,636
kwh/year, and industrial development will use 35,388,304 kwh/year.78
In the overall, increased demand associated with implementation of the General Plan will
contribute to the regional demand for electricity. The City is completing a Greenhouse Gas
77 Written communication provided by Guillermo Barraza, Customer Operations and Planning, Imperial Irrigation
District, December 21, 2010. 78 “La Quinta General Plan Air Quality Report,” prepared by Terra Nova Planning and Research, July 2011.
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Reduction Plan as part of the General Plan Update. The Reduction Plan includes measures to
reduce energy use. In addition, the General Plan’s Sustainable Community Element includes
policies for resource conservation, including energy conservation for development projects in the
City. These policies will reduce the relative consumption of electricity in the City as the General
Plan builds out.
Imperial Irrigation District is a publicly traded company. It has established a rate structure that
accommodates growth through the extension of facilities. Build out of the General Plan Area is
expected to occur over time. Therefore, IID’s expansion plans will be adjusted to accommodate
it, and impacts are expected to be less than significant.
3. Mitigation
IID’s rate structure includes expansion to accommodate expansion, which is expected to occur
gradually over time. No significant impact is expected, and no mitigation measures are required.
Natural Gas
1. Existing Conditions
Southern California Gas Company provides natural gas services and facilities within the City and
its Sphere of Influence. Residents use natural gas as the primary energy source for cooking and
for heating space and water.
High-pressure transmission lines are located north of US Interstate 10 and deliver natural gas to
the region. These lines are 36-inch diameter lines with 400 to 700 pounds per square inch (psi)
pressure capacities. Limiting stations located throughout the region reduce pressure, and from
there gas is distributed through supply lines ranging in diameter from 2 to 8 inches. Within the
Planning Area, there are major natural gas supply lines within Washington Street and Highway
111. Regulator stations further reduce pressure and transfer it to distribution lines for delivery to
residential and business customers.
Some areas of the City and Sphere have limited access to natural gas service. These include the
southern portion of the City and Sphere, especially south of Airport Boulevard and east of
Monroe Street, as well as within portions of the La Quinta Cove, and some older developments
in the Sphere. In these areas, propane gas purchased from private firms is utilized.
Based on estimates provided by the Southern California Gas Company, average annual natural
gas consumption for residences is 29,093 cubic feet (cf). The following table shows estimated
natural gas consumption factors for various land uses.79
79 Data provided by Southern California Gas Company, August 13, 2010.
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Table III-41
Natural Gas Consumption Factors
Residential 29,093 cubic feet/unit/year
Commercial 53.22 cubic feet/square feet/year
Industrial 53.22 cubic feet/square feet/year
Source: Terra Nova Staff estimates based on .2005 historical data provided by Southern
California Gas Company, August 13, 2010.
Based on these factors, residential, commercial and industrial gas customers in the City
consumed 1,025 million cubic feet of natural gas. In the Sphere for the same period, residential
and commercial customers used 37,819,780 cubic feet. In the overall, natural gas customers in
the Planning Area used over 1 billion cubic feet of natural gas.80
2. Impacts
At build out, there are expected to be 46,866 single-family and 6,236 multi-family dwelling units
in the Planning Area. There is expected to be 12,364,631 square feet of commercial space, and
611,408 square feet of industrial space.
Applying the factors in Table III-41 to these land uses, single-family units will use
approximately 1,371,560,392 cubic feet of natural gas per year (cf/year), and multi-family units
will use approximately 175,314,418 cf/year.81
For commercial and industrial uses, consumption will be approximately 658,912,550 cf/year and
32,539,142 cf/year, respectively. At build out, all development in the General Plan Planning
Area is expected to consume approximately 2,238,326,502 cubic feet per year. This accounts for
both existing and future development in the Planning Area. A variety of factors will determine
actual natural gas consumption, including future levels of development, individual project
designs, and the effectiveness of energy-conserving measures.
3. Mitigation
Southern California Gas Company has developed a rate structure that provides for facilities’
expansion. Therefore, impacts are not expected to be significant impact and no mitigation
measures are required.
80 Terra Nova Staff estimates based on 2005 historical data provided by Southern California Gas Company,
August 13, 2010. 81 Terra Nova Staff estimates based on 2005 historical data provided by Southern California Gas Company,
August 13, 2010.
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Domestic Water Services
1. Existing Conditions
Domestic and irrigation water within the City and most of the Sphere is provided by Coachella
Valley Water District (CVWD). Groundwater is CVWD’s primary domestic water source; water
is extracted from deep wells located throughout the City and region. CVWD also relies on
imported water, which is used to supply recharge basins located near Palm Springs, as well as in
southern portion of the Planning Area south of Lake Cahuilla, and in Martinez Canyon, south
and east of the City.
In general the water distribution system, owned and operated by CVWD, is located within the
public right of way under existing streets. CVWD has water storage reservoirs within its service
area. In the La Quinta Planning Area, there are 10 existing or planned tanks. The tanks range in
capacity from 250,000 to 12 million gallons.
California Water Code requires that CVWD prepare and periodically update an Urban Water
Management Plan (UWMP) to analyze current and future water supplies to ensure that it has
sufficient supplies to serve land uses within its service area. Additional information regarding
water resources is provided in Section III-P, Water Quality and Resources.
2. Impacts
A Water Supply Study (WSS)82 has been prepared to assess future water demands relative to
supplies for the proposed General Plan at build out. As discussed in the WSS, the proposed
General Plan will result in increased water demand associated with development, such as
residential, commercial, and industrial, as well as open space amenities, street rights-of-way and
others. An estimate of increased demand is shown in Section III-I. Water consumption factors
and methodology utilized to project water demand are explained in the WSS. Based on the
assumptions set forth therein, build out of the proposed General Plan Update is expected to result
in an annual water demand of 54,467 acre-feet.
The General Plan will facilitate development that will cumulatively increase impacts to
groundwater supplies in the region. The amount of potable groundwater in storage will also be
reduced. As discussed in Section III-I, development in the region will occur gradually, as will
impacts to groundwater supplies. For a more thorough discussion of impacts to water resources
and quality, please see Section III-P.
3. Mitigation
Mitigation measures to reduce potential impacts associated with domestic water to less than
significant levels are shown below. Additional measures are included in Section III-P, Water
Resources/Quality.
82 “La Quinta General Plan Water Supply Study,” prepared by Terra Nova Planning & Research, July 2011.
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1. The City and Coachella Valley Water District shall review and evaluate all future
development projects for their potential impact on local groundwater supplies.
2. The City shall continue to require the use of drought tolerant landscaping in new and
rehabilitated public and private development, and shall encourage its use in existing
development.
3. Future development shall be required to conform to standards set forth in Section 17921.3 of
the Health and Safety Code, Title 20, California Administrative Code Section 1601(b), and
applicable sections of Title 24 of the State Code. Measures set forth in these statutes include
the installation of low-flow showerheads and faucets and low-flush toilets in all new
construction.
Mitigation Monitoring and Reporting
A. All development proposals shall be reviewed by the Planning Department and the City
Engineer for their potential to result in adverse impacts to water quality and quantity. The
City shall require that any potential significant impacts be mitigated prior to project approval.
Responsible Parties: Planning Department, City Engineer, Coachella Valley Water District
Wastewater Collection and Treatment
1. Existing Conditions
Sanitary sewer collection and treatment facilities are provided by the Coachella Valley Water
District within most of the City and Sphere. Where sewer facilities are not available, residences
utilize septic systems. These occur primarily in the Sphere.
There are two CVWD wastewater treatment plants that serve La Quinta. Water Reclamation
Plant 7 (WRP-7) is located at Madison Street and Avenue 38, northeast of the City in Indio. It
provides wastewater treatment for development in the City north of Miles Avenue. The capacity
of WRP-7 is 5 million gallons per day (mgd), and the plant processes approximately 2.8 to 3.0
mgd. It has the capacity to expand to 7.5 mgd. Currently there is sufficient excess capacity;
therefore, although expansion capacity exists, no such plans are imminent.83
WRP-7 has facilities to treat wastewater to tertiary levels, which is suitable for irrigation but is
not potable. The plant’s tertiary capacity is 2.5 mgd. Planning is currently underway to design
expansion of the tertiary system to 5.0 mgd, however no target date has been set for completion
of this expansion. Current economic conditions have resulted in steady or slightly reduced
demand. WRP-7 tertiary water provides irrigation for the Del Webb and Shadow Hills
developments. 84
83 “Engineer’s Report on Water Supply and Replenishment Assessment: Lower Whitewater River Subbasin Area
of Benefit, 2010-2011,” prepared by Coachella Valley Water District, April 2010.” 84 Personal communication, Ray Salazar, CVWD-WRP-7, December 15, 2010.
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The Mid-Valley Water Reclamation Plant (WRP-4), located in Thermal, serves lands in the City
and Sphere that are located south of Miles Avenue. The Mid-Valley plant has a current capacity
of just under 10 mgd, and processes approximately 5 mgd per day. Given the excess capacity,
there are currently no plans for expansion at the Mid-Valley plant. WRP-4 does not include
tertiary treatment facilities. 85 CVWD indicates that such facilities could be located at this plant
in the future should demand warrant.86
CVWD sewer lines utilize a system of trunk lines ranging in diameter from 4 to 24 inches. There
are 18-inch diameter force mains in Washington Street, Jefferson Street, Madison Street, and
Avenues 50, 58 and 60.
2. Impacts
Implementation of the General Plan will facilitate development that will increase demand on
existing wastewater collection and treatment facilities. It is assumed that domestic wastewater
flows are equivalent to the potable water demand projections, which average approximately 69.3
gallons per capita per day in 2010 and are projected to average 55.44 gpcd at build out. Using
this approach, it is estimated that in 2010 the City of La Quinta generated approximately 4.1
million gallons per day (gpd) of wastewater. It is expected that, at build out, the City of La
Quinta will generate approximately 4.4 million gallons per day of wastewater. Wastewater
generation in the Sphere is estimated to be 140,471 gallons per day in 2010. At build out, the
Sphere is projected to generate approximately 3.0 million gallons of wastewater per day, which
is an increase of about 2.8 million gallons by 2035. Total wastewater generation in the Planning
Area at build out is projected to be approximately 7.4 million gpd, which is an increase of
approximately 3.1 million gallons over estimated 2010 conditions.
This level of wastewater generation is substantial; however it will not exceed the combined
treatment capacity at the CVWD treatment plants serving the Planning Area. Further, CVWD
continues to plan for expansion as needed. As future development occurs, existing facilities may
need to be expanded to build out capacity to accommodate wastewater generation. Further, it is
expected that existing development currently served by private septic systems will connect to
community sewer systems over the course of General Plan build out.
Development in the General Plan area will occur gradually over time. The City and CVWD will
have an opportunity to plan for increased development, including construction of new sewer
collection facilities and increased treatment capacity. Nevertheless, growth trends will need to be
monitored to ensure that adequate wastewater treatment facilities are provided to serve the
Planning Area. As future development connects to sewer facilities, it will continue to be subject
to connection fees.
3. Mitigation
85 Personal communication, Kim Halsey, CVWD WRP-4, December 14, 2010. 86 “Draft Coachella Valley Water District Urban Water Management Plan,” prepared by Montgomery Watson
Harza, December 2010.
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Although sufficient capacity appears to be available to serve future development through existing
treatment facilities, the City and CVWD will need to continue to monitor growth to ensure that
adequate capacity is available as the Planning Area builds out.
In order to ensure that potential impacts associated with wastewater collection and treatment are
reduced to less than significant levels, the following mitigation measures will be implemented.
1. To the greatest extent practicable, the City shall require that all new development be
connected to sanitary sewer service.
2. The City shall ensure coordination with the Coachella Valley Water District and to assure
that existing and future extended sanitary sewer facilities are adequate to meet the needs of
existing and expected future development.
3. The City and Coachella Valley Water District should encourage the replacement of existing
septic systems with connection to sanitary sewer facilities to the greatest extent feasible.
Mitigation Monitoring and Reporting
A. The City Planning and Public Works Departments shall confer and consult with Coachella
Valley Water District to implement City-wide wastewater collection and treatment facilities
and service.
Responsible Parties: Planning Department, Public Works Department, Coachella Valley
Water District.
B. All development proposals for future development shall be reviewed by the Planning and
Public Works Departments to ensure connection with sanitary sewer services.
Responsible Parties: Planning Department, Public Works Department, Coachella Valley
Water District.
Solid Waste Management
1. Existing Conditions
The City has a franchise agreement with Burrtec Waste and Recycling Services, LLC (Burrtec)
for the provision of solid waste disposal in the City and Sphere. Non-hazardous household,
commercial and most non-hazardous industrial solid waste collected in the Planning Area is
taken to the Edom Hill Transfer Station in Cathedral City. From there, waste is transported to the
Lamb Canyon regional landfill, which is owned and operated by Riverside County.
The Lamb Canyon landfill is located between the cities of Beaumont and San Jacinto at 16411
Lamb Canyon Road (State Route 79). The landfill is permitted to receive a maximum of 5,000
tons per day. As of January 2010, the landfill had a total remaining capacity of approximately
9.2 million tons. During second and third quarter 2009, average daily receipts totaled
approximately 1,697 tons per day. The landfill site encompasses 1,189 acres, of which
approximately 581 acres are currently permitted for landfill use, and 145 acres are permitted for
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waste disposal. It is projected that current landfill capacity will extend to 2021, at a minimum.
The Lamb Canyon landfill has potential for expansion. 87
In future, solid waste from the Planning Area may also be transported to other regional landfills,
including the Badlands facility, located in Moreno Valley, and the El Sobrante landfill in
Corona. Both of these landfills currently have excess capacity.
Solid waste recycling is also provided by Burrtec, which collects paper, plastic, glass and
aluminum from residences and businesses. Mixed recyclables are transferred to Burrtec facilities
in northern San Diego County.88
Burrtec also has green waste recycling capabilities. Brush and other greenwaste from La Quinta
are taken to the Edom Hill Transfer Station, and are eventually composted or sent to the Colmac
Energy plant in Mecca for use as bio fuel.
The Integrated Waste Management Act (AB 939), passed in 1989, requires California cities and
counties to meet a variety of recycling and reuse goals, including diverting at least 50% of their
solid waste stream through new and ongoing waste and recycling programs. La Quinta is
meeting these State-mandated goals.
Data from the California Integrated Waste Management Board indicates that as a result of the
enactment of this legislation, recycling efforts annually conserve enough energy to provide
power for 1.4 million California homes, reduce water pollution by 27,047 tons, save 14 million
trees, reduce air pollution by 165,142 tons, and reduce greenhouse gas emissions by an amount
equal to taking 3.8 million passenger cars off the highway.89
Solid waste generated by construction and demolition sites may accounts for as much as 22% of
the solid waste stream.90 Prior to the issuance of grading permits, the City refers developers to
Burrtec environmental staff to develop a recycling plan to recycle at least 50% of these
materials.91 Although not yet mandated, these reductions can result in substantial cost savings to
developers. It is expected that these will be required in the near future.
In 2009, residential development in the City generated 11,414.6 tons of solid waste; commercial
development generated 3,615.3 tons. Approximately 4,393.4 tons of recyclables were collected
from residential curbside pick ups; approximately 3,908.1 tons of residential greenwaste were
collected curbside. Commercial on-site pick up units accounted for 1,050.5 tons of recyclables,
and on-site greenwaste totaled 4,607.1 tons.92
87 Written communication, Ryan Ross, Riverside County Waste Management Department, December 17, 2010. 88 Personal communication, Ken Stevens, Burrtec District Environmental Coordinator, December 14, 2010.
89 National Recycling Coalition’s Environmental Benefits Calculator using California data from 2001 studies by
UC Berkeley and the National Recycling Coalition, found at CalRecycle Internet Search, December 20, 2010.
90 Statewide Waste Characterization Study, prepared by the California Integrated Waste Management Board,
December 2004. 91 Personal communication, Ken Stevens, Burrtec District Environmental Coordinator, December 14, 2010. 92 Data for City of La Quinta provided by Burrtec, January 2010.
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Hazardous Waste93
The information above is applicable for non-hazardous household, commercial and most
industrial solid waste. Household hazardous waste (HHW), such as household cleaning
chemicals, flammables, batteries, motor oil, antifreeze and paint, and others are collected at three
permanent facilities provided by the Riverside County Waste Management Department. These
facilities also accept sharps and needles. The HHW collection facilities are located in Palm
Springs, Lake Elsinore, and Riverside, and are open every Saturday except for designated
holidays. There are also a number of one-day collection “events” at various locations and dates
throughout the County, including the City’s Civic Center.
Coachella Valley Area Regional Antifreeze, Battery, Oil (and Filter) and Paint (Latex)
Collection Facilities (ABOP) collect only these specified HHWs. There are three facilities,
including two in the Coachella Valley: at the Edom Hill Transfer Station in Cathedral City and
the Coachella Valley Transfer Station in Coachella. The Edom Hill ABOP facility operates on
Saturdays, and the Coachella facility is open Monday through Saturday.
The County also administers special programs such as collection of construction and demolition
materials and commercial recycling.
County-approved hazardous waste disposal firms (private contractors) collect hazardous
industrial waste, which is disposed of at sites other than County landfills. In general these wastes
have been disposed of at Cattleman’s Hill in central California. Hazardous waste and hazardous
waste disposal is discussed in further detail in Section III-G, Hazards and Hazardous Materials.
2. Impacts
Development facilitated by build out of the General Plan will result in increased generation of
solid waste. The three existing landfills have long-term capacity sufficient for expected solid
waste generated in the Planning Area, and Burrtec plans on providing service to accommodate
future development. As the City continues to implement existing and initiate new recycling
efforts, it expected that impacts to regional landfills will be decreased.
Based on solid waste generation factors provided by the California Integrated Waste
Management Board applied to land uses in the proposed General Plan Land Use Plan provides an
estimate of solid waste generation at build out. The following tables show estimated solid waste
generation in the Planning Area.
93 http://www.rivcowm.org/HHW_Schedule.htm#_HHW_Collection_Locations
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Table III-42
Solid Waste Generation at
General Plan Build Out
Land Use Type
Generation
Rate Unit Type
Units
(DU/Sq. Ft.)
Annual Tons
of Solid Waste
Single Family 2.0400 tons/unit/year 46,866 95,606.64
Multi Family 1.1700 tons/unit/year 6,236 7,296.12
Retail/Commercial1 0.0024 tons/sf/year 12,364,631 29,675.11
Industrial 0.0108 tons/sf/year 611,408 6,603.21
Total 139,181.08
1 Assumes development of all General, Tourist and Village Commercial based on retail/commercial factor.
Source: Terra Nova staff estimates based on California Integrated Waste Management Board compilation of
waste generation rates. Rates used are from Ventura County Solid Waste Management Department,
“Guidelines for Preparation of Environmental Assessments of Solid Waste Impacts”, September 1992, and
“DEIR for North Hills Development in Santa Clarita”, December 1991.
At build out, implementation of the General Plan is expected to result in approximately 53,103
dwelling units. Of these, approximately 46,866 will be single-family units, and approximately
6,236 will be multi-family units. Up to approximately 12,364,631 square feet of commercial
development, which is assumed to be primarily retail uses, and 611,408 square feet of industrial
development will also be constructed. As shown above, based on this level of development,
approximately 139,181 tons of solid waste would be generated per year. On a daily basis, this
equates to 381 tons of solid waste. Actual waste generation will depend on future levels of
development, and participation in stream flow diversion programs.
There are no proposed land uses that are expected to generate large quantities of solid waste or
create conditions where severe hazardous wastes are produced. Development facilitated by the
General Plan will nonetheless result in increased volumes of solid waste generation. Therefore,
the City and Burrtec will need to continue to monitor these levels to ensure that disposal of solid
and hazardous wastes generated in the Planning is safe and cost-effective.
3. Mitigation
The most effective way to reduce impacts to landfills is through reduction of solid waste at the
source. The following mitigation measures are intended to further reduce the amount of waste
generated in the Planning Area, promote the City’s compliance with AB 939 and AB 341, and
mitigate impacts to landfills by reducing the amount of waste generated.
1. The City shall continue to consult and coordinate with Burrtec to sustain and exceed the
provisions of AB 939 and AB 341 where possible through expanding its recycling programs
and divert resources from the waste stream for return to productive use.
2. Commercial and industrial establishments shall be required to comply with State mandates
established under AB 341 to reduce the amount of packaging and potential waste associated
with product manufacturing and sales.
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3. The City and Burrtec shall continue to include recycling provisions for single-family and
multi-family residential dwelling units in their solid waste disposal contracts.
4. Prior to the issuance of building permits, the City shall continue to refer project developers to
Burrtec for development of construction and demolition solid waste recycling plans to divert
a minimum of 50% of C&D debris from the waste stream.
Mitigation Monitoring and Reporting
A. Prior to the issuance of building permits, the City Planning and Building and Safety
Departments shall review project development plans and confer and coordinate with project
developers to assure the provision and maintenance of recycling containers that correspond
with current City programs and those planned in the future, including those for construction
and demolition solid waste.
Responsible Parties: Planning Department, Building and Safety Department, Burrtec Waste
and Recycling Services, LLC.
Public Transportation Services
1. Existing Conditions
The Sunline Transit Agency provides public transportation services to residents and visitors
throughout the Coachella Valley, including the City of La Quinta. There are two primary Sunline
routes within the City of La Quinta. Bus line 111 generally runs along Highway 111, thereby
providing public transportation serveries to destinations located in the vicinity of Highway 111.
Bus Line 70 generally runs along Washington Street, providing public transportation to northern
and southern destinations within the City of La Quinta.
2. Impacts
Implementation of the proposed General Plan is expected to increase the demand for public
transportation services. The Traffic and Circulation discussion, Section III-O below further
addresses current and planned future bus routes, other public transportation opportunities, and
potential impacts associated with build out of the General Plan.
3. Mitigation Measures
1. The City of La Quinta shall continue to coordinate with SunLine Transportation Agency
to establish new bus stop locations and facilities as demands warrant.
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Recreational Resources N.
Introduction
The City of La Quinta has numerous recreational resources that improve the quality of life for its
residents and make La Quinta a desirable destination. This section assesses impacts on
recreational resources from future growth and development brought on by the La Quinta 2035
General Plan Update. It also provides mitigation measures to reduce impacts on existing
recreational facilities and impacts associated with development of new facilities.
Thresholds of Significance/Criteria for Determining Significance
Article 5, Section 15064 of the CEQA Guidelines provides guidance for determining the
significance of the environmental effects caused by a project. Appendix G of the CEQA
Guidelines provides a list of environmental factors that potentially may be affected by
completion of a project. The La Quinta 2035 General Plan Update would have a significant
effect on Recreational Resources if it is determined the plan:
a) Would increase the use of existing neighborhood and regional parks or other
recreational facilities such that substantial physical deterioration of the facility would
occur or be accelerated.
b) Includes recreational facilities or require the construction or expansion of recreational
facilities, which might have an adverse physical effect on the environment.
1. Existing Conditions
The General Plan Update Planning Area, and particularly land within the City limits, offers a
variety of passive and active recreational opportunities for residents and visitors to the region.
There are approximately 5,259 acres of open space areas set aside for recreational facilities in the
City. These developed open space recreational areas include a variety of city owned and
maintained parks and facilities, County owned parks, Desert Recreation District facilities and
public and private golf courses. In addition, there are approximately 6,933 acres of natural open
space areas in the City Limit offering hiking trails, equestrian trails, and other passive recreation
opportunities. The City of La Quinta also offers numerous golf courses and resorts, making it a
premier destination for golf.
City Recreational Resources
The City owns, operates and maintains numerous park facilities throughout incorporated areas of
the General Plan Update Planning Area. Within the City Limits are five mini parks, including
Eisenhower Park, Seasons Park, Saguaro Park, Desert Pride and Velasco Park. These parks are
generally one acre or less than one acre in size and are located within neighborhoods. Mini parks
provide limited amenities including small children play areas, playground equipment, turf areas,
walking paths and areas for seating.
Neighborhood parks are larger than mini parks and provide both active and passive recreational
needs for the community. These include parks such as Fritz Burns Park, Adams Park, Monticello
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Park, and Pioneer Park. Neighborhood parks are generally two to ten acres in size and can
include large field facilities for sporting events, children play areas, interactive water features,
dog park facilities, picnic and barbecue amenities, restroom, and other additional community
features. Pioneer Park is the newest neighborhood park in La Quinta and provides 2 acres for a
playground, dog park, and passive seating areas. The Fritz Burns Park provides a swimming pool
operated by Family YMCA of the Desert.
The third type of city-operated park includes community parks. Community parks are generally
15 to 40 acres in size and provide both large-scale recreational amenities, such as baseball fields,
soccer fields, softball fields, basketball courts, skate parks, and playgrounds, and also restrooms,
barbecues, public art displays, water features, picnic facilities, and benches. There are three
community parks in La Quinta including the 16.75-acre La Quinta Sports Complex, the 18-acre
La Quinta Park, and the 17.5-acre Civic Center Campus. Community parks provide recreational
resources for City residents and the surrounding region.
The City of La Quinta owns and operates open space areas and trail systems throughout the
incorporated limits. The Fred Wolff Nature Preserve is a 19-acre natural open space area located
just off the Bear Creek Trail, on the western portion of the Cove area. The City purchased the 19
acres in June of 2003 as a nature preserve, and to provide additional opportunities for hiking and
learning about the desert plant species and wildlife. The Cove Oasis Trailhead is another natural
open space area located at the southernmost part of the Cove. This open space area includes 114
acres and includes amenities such as hiking trails, picnic tables and benches, water fountains,
public art displays, and areas available for event rentals. Many area trails connect at the Cove
Oasis Trailhead including the Cove to Lake Trail, Boo Hoff Trail, Bear Creek Oasis Trail, Bear
Creek Canyon and the city maintained Bear Creek Trail. Bear Creek Trail is a 4.75-acre hiking
path that connects the Fred Wolff Nature Preserve with the Cove Oasis Trailhead.94
The City also operates and maintains the La Quinta Senior Center and La Quinta Museum. The
La Quinta Senior Center provides services such as classes, seminars, special events, and weekly
programs to adults 55 years of age and older. The La Quinta Museum provides local residents
cultural activities, including art exhibits, programs, and events.
Desert Recreation District Facilities
The Desert Recreation District provides park facilities and recreation programs throughout the
Coachella Valley. Once known as the Coachella Valley Recreation and Park District, the Desert
Recreation District owns and operates the La Quinta Community Center, and is proposing a
Discovery Center near Lake Cahuilla.
The La Quinta Community Center and Park is located off Avenida Montezuma, and includes a
6.5-acre park and 5,000 foot community center. The 6.5-acre park includes ballfields, basketball
courts, playground, picnic tables, barbecues, restrooms, an outdoor amphitheater, outdoor
exercise facilities, and drinking fountains. The Community Center includes the La Quinta Fitness
Center, kitchen, and concessions.
94 “Parks and Trails” www.la-quinta.org, accessed November 22, 2010.
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The proposed Coral Mountain Discovery Park will be a partnership between the Bureau of Land
Management and the Desert Recreation District, and encompass 620 acres of open space, of
which 123 acres will be available for public access. The public access area will provide
interpretive trails, picnic areas and a learning center. The Discovery Park will be the Coachella
Valley’s first archaeological park and provide residents the opportunity to learn about the regions
rich cultural and natural heritage. 95
Riverside County Regional Park and Open Space District
Riverside County operates Lake Cahuilla Regional Park located in southwestern portion of La
Quinta. The 710-acre Regional Park includes a 113-acre lake, 20 equestrian campsite, 30
primitive individual campsites, showers, and dump stations, as well as other amenities including
shore fishing, equestrian and hiking trails, and picnicking facilities. Swimming is not allowed in
Lake Cahuilla, however a seasonal swimming pool is open from mid April to mid October. 96
Bureau of Land Management Land
The Bureau of Land Management (BLM) provides and manages large areas of open space
throughout the southwestern portion of the City limits and the Sphere of Influence. Although
located within City of La Quinta jurisdictional boundaries, the General Plan Update will not have
jurisdiction over these federally managed public lands. The Santa Rosa and San Jacinto National
Monument were established by the federal government in 2000 “in order to preserve the
nationally significant biological, cultural, recreational, geological, educational, and secure now
and for future generations the opportunity to experience and enjoy the magnificent vistas,
wildlife, land forms, and natural and cultural resources in these mountains and to recreate
therein.”97 The Monument encompasses nearly 272,000 acres, however the portion closest to La
Quinta includes the 61,600-acre Santa Rosa Wilderness. The Bear Creek Canyon Trail, located
in the southern portion of the Cove area, provides entrance into the Santa Rosa Wilderness.
Golf Courses
La Quinta has numerous public and private courses throughout the community. There are several
well-known courses throughout the incorporated Planning Area, including PGW West,
SilverRock Resort, La Quinta Resort Golf Course, Trilogy Golf Club, and a number of private
courses within country club communities.98
95 Desert Recreation District, www.myrecreationdistrict.com, accessed November 22, 2010. 96 Lake Cahuilla, Riverside County Parks, www.rivcoparks.org/parks/lake-cahuilla/lake-cahuilla-recreation-area-
home/, accessed July 5, 2011. 97 Santa Rosa and San Jacinto Mountains National Monument, http://www.blm.gov/, accessed November 22,
2010. 98 http://www.playinlaquinta.com/golf.html
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Sphere of Influence Recreational Resources
The Sphere of Influence has no parks or other recreational uses. The eastern Sphere of Influence
Planning Area also has schools, including Westside Elementary School, and is adjacent to
Coachella Valley High School.99 These schools provide athletic fields and hardtop courts,
however these uses are generally for school purposes. Equestrian facilities are found in the
eastern Sphere of Influence, including the Mountain View Equestrian Center along Jackson
Street, just south of Avenue 58th Avenue.100 There are local equestrian trails throughout the
eastern Sphere of Influence that provide places for riding.
Quimby Act
California passed the Quimby Act in 1975, allowing local governments to pass ordinances
requiring developers to set aside land, donate conservation easements, or pay in-lieu of fees for
the development of new parks and recreational facilities. Local governments have come to
depend on the Quimby Act for new facilities, or to upgrade existing facilities, as a result of new
growth and development. La Quinta Municipal Code Section 13.48 establishes criteria for
dedicating land, or payment of in lieu fees for construction of new parks or recreational facilities
or rehabilitation of existing facilities. The ordinance states that residential subdivisions,
containing less than five parcels, and nonresidential subdivisions, are exempt from dedication or
park fees. All other residential developments are required to pay a park development fee,
dedicate land, or both. Section 13.48.050 states that parkland dedication requirements shall equal
three acres of parkland per one thousand people in a new subdivision. The number of people in a
new subdivision is determined by multiplying the number of dwelling units in the subdivision by
the average household size. Average household size is based on the latest U.S. Census
information.
2. Project Impacts
The La Quinta 2035 General Plan Update will facilitate new development that will create
demand for new parks and recreational facilities. Implementation of General Plan Update will
result in approximately 8,114 new residential units within the City Limits and 20,669 new
residential units within the Sphere of Influence. At build out, the total number of dwelling units
within the City will be approximately 31,603 units, and 21,500 within the Sphere of Influence.
Total build out population is expected to be 79,956 in the City Limits and 54,396 within the
Sphere of Influence, for a grand total of 134,352 throughout the General Plan Update Planning
Area.
Impacts on Existing Neighborhood and Regional Parks
The General Plan Update will facilitate new residential development throughout the Planning
Area, and increase the population within City Limits. New growth will put pressure on existing
facilities, if no new recreational facilities are built. As mentioned above, however, there are
99 http://www. maps.google.com/ 100 http://www.mountainviewequestriancenter.com/About-Us.html
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already 5,259 acres of recreational open space, and 6,933 acres of natural open space within the
City.
The General Plan requires the provision of 5 acres of parkland for each 1,000 population. Based
on this standard, a population of 79,956 at build out would require a total of 395 acres of
parkland. With implementation of required fees for new development projects, implementation
of the General Plan Update will have less than significant impacts to existing parks within the
City.
Implementation of the General Plan Update has the potential to result in the development of
approximately 20,699 new residential units within the Sphere at build out. Total population
within the Sphere is expected to reach 54,396 residents. The General Plan requires 5 acres of
parkland per 1,000 residents. Based on this standard, a population of 54,396 residents at build
out would require a total of 272 acres of parkland, if the Sphere were annexed to the City. With
implementation of required fees for new development projects, implementation of the General
Plan Update will have less than significant impacts to existing parks within the City.
3. Mitigation Measures
None required.
Transportation/Traffic O.
Introduction
This section of the EIR describes the existing condition of traffic and circulation within the City
and Sphere-of-Influence, the vicinity and the region. It also analyzes the potential impacts of the
proposed La Quinta General Plan update and sets forth strategies and mitigation measures that
will be effective in reducing impacts. A wide range of data and information, ranging from
research and analysis conducted for specific projects in the area, to regional-scale planning and
environmental documents, have been used in researching and analyzing the General Plan project
and its potential effects. 101, 102, 103 These include detailed analysis of major roadway segments,
as well as detailed analysis of future traffic and circulation conditions104,105.
General Plan Traffic Impact Analysis
A traffic impact analysis was prepared for the General Plan update by Iteris, Inc. to assess the
existing roadway network, collect data on and measure the level of use and service along the
existing roadways in the General Plan study area. The traffic impact analysis also identifies
potentially significant traffic-related impacts associated with build out of the City’s General
101 “City of La Quinta General Plan Circulation Element Update Traffic Impact Analysis” prepared by Iteris, Inc. May 2012. 102 "County of Riverside General Plan”, prepared by County of Riverside Transportation and Land Use Management Agency,
October 2003.
103 “Riverside County Transportation Analysis Model (RivTAM)” prepared by the Riverside County Transportation
Department, 2008. 104 “Washington Street & Highway 111 TSM/TDM Corridor Study” prepared by VRPA Technologies, Inc. June 2009. 105 "Panorama (Specific Plan No. 362) Traffic Impact Analysis" prepared Urban Crossroads, Inc., July 5, 2007.
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Plan, as well as surrounding lands, and sets forth detailed mitigation measures and strategies
designed to reduce potential impacts to levels that are less than significant.
The primary goals of the La Quinta General Plan traffic analysis was to: (1) documentation of
existing traffic volumes and operating conditions at all major intersections and along major r oadway
within the City and Sphere of Influence; (2) evaluation of existing plus projected background
growth, plus General Plan build out traffic for 2035 conditions; (3) evaluation of existing plus
General Plan build out traffic for 2035 conditions; and (4) determination of improvements and
system management action needed to achieve City level of service requirements.
Thresholds of Significance/Criteria For Determining Significance
The following thresholds or criteria are not strictly those recommended in Section 15064 of the
CEQA Guidelines. Rather, they are derived from Appendix G of the CEQA Guidelines, which is
used to determine the level of potential effect, and whether a Negative Declaration or Mitigated
Negative Declaration may be issued, or whether an Environmental Impact Report is to be
prepared. The subject La Quinta General Plan update, and the General Plan Land Use
Alternatives, would have a significant effect on transportation/traffic if they:
a.) Conflict with an applicable plan, ordinance or policy establishing measures of effectiveness
for the performance of the circulation system, taking into account all modes of
transportation including mass transit and non-motorized travel and relevant components of
the circulation system, including but not limited to intersections, streets, highways and
freeways, pedestrian and bicycle paths, and mass transit?
b.) Conflict with an applicable congestion management program, including, but not limited to
level of service standards and travel demand measures, or other standards established by
the county congestion management agency for designated roads or highways?
c.) Result in a change in air traffic patterns, including either an increase in traffic levels or a
change in location that results in substantial safety risks.
d.) Substantially increase hazards due to a design feature (e.g., sharp curves or dangerous
intersections) or incompatible uses (e.g., farm equipment).
e.) Result in inadequate emergency access.
f.) Result in inadequate parking capacity.
g.) Conflict with adopted policies, plans, or programs regarding public transit, bicycle, or
pedestrian facilities, or otherwise decrease the performance or safety of such facilities.
The following discussion provides some essential background information to facilitate a better
understanding of the analysis, which follows.
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Levels of Service
The capacity of a segment of roadway or an intersection is typically characterized as “Level- of-
Service”. As gauged for mid-block (segment) travel, Level-of-Service (LOS) is a qualitative
measure describing the character and efficiency of the flow of traffic. For intersections, the LOS
is defined quantitatively as the number of seconds the vehicle is delayed in passing through the
intersection. LOS includes a range of alphabetical connotations “A” through “F”, used to
characterize roadway operating conditions. LOS A represents the best/free-flow conditions and
LOS F indicates the worst/system failure.
Intersections generally represent the most constrained portion of the roadway network. The
Transportation Research Board Highway Capacity Manual expresses the Level of Service at an
intersection in terms of delay or waiting time to get through the various intersection approaches.
For signalized intersections, average total delay per vehicle is used to determine the LOS.
Intersection LOS is defined quantitatively in Table III-43 below. A more detailed discussion of
LOS values can be found in the General Plan Traffic Impact Analysis in the EIR Technical
Appendices.
Mid-block Levels of Service are represented as volume to capacity ratios, or vehicle demand
divided by roadway capacity. In general terms, as the ratio approaches 1.00 or maximum
capacity, the roadway approaches LOS F. However, it is important to keep in mind that for mid-
block, the LOS is meant to define a qualitative rather than a quantitative measure of operation.
The LOS assignment is only marginally useful in characterizing capacity, and is not meant to
determine actual volumes that a particular roadway segment can carry. Mid-block volumes and
volume to capacity ratios (V/C) should be used as a means of monitoring traffic flows toward the
intersections and can inform traffic engineers of areas where further analysis is warranted.
A variety of conditions and mix of improvements can enhance mid-block roadway capacity.
Adding through and turning lanes increases capacity, as do the inclusion of raised medians and
restricted access on a roadway. Restricted access and raised medians increase roadway capacity
by reducing the number of vehicle conflict points and improving traffic flows. Restricted access
avoids loss of capacity caused by interruptions and disruptions to traffic flow resulting from
vehicles coming onto or leaving the roadway.
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Table III-43
Level Of Service Description
Mid-Link and Uninterrupted Flow
Level of Volume/Capacity
Service Quality of Traffic Flow Ratio
A Free flowing, low volumes, high speed; speed not restricted by
other vehicles in the traffic stream. 0.00 - 0.60
B Operating speeds and maneuverability in the range of stable flow,
but presence by other traffic begins to be noticeable. Freedom to
select desired speeds is relatively unaffected, but there is a slight
decline in the freedom to maneuver. 0.61 - 0.70
C Operating speeds and maneuverability significantly controlled by
other traffic Quality of operations still within the range of stable flow. 0.71 - 0.80
D Tolerable operating speeds, high traffic density but stable flows;
often used as design standard in urban areas. At this level, speed and
freedom to maneuver are severely restricted. Drivers experience
general discomfort and inconvenience. 0.81 - 0.90
E At or near maximum traffic volume a roadway can accommodate
during peak traffic periods. Low speed but uniform traffic density.
“Maximum Capacity”. Highly susceptible to breakdowns in flow. 0.91 - 1.00
F System failure; long queues of traffic; unstable flows; stoppages of Not Meaningful
long duration; traffic volume and speed can drop to zero; traffic
volume will be less than the volume which occurs at Level
of Service E.
Source: Highway Capacity Manual, Transportation Research Board - Special Report 209,
National Academy of Science, Washington, D.C. 2000.
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Table
III-‐44
Intersection Level Of Service Descriptions
Level of
Service
Description Signalized
Intersection Delay
(seconds per
vehicle)
Unsignalized
Intersection Delay
(seconds per
vehicle)
A Excellent operation. All approaches to the
intersection appear quite open, turning
movements are easily made, and nearly all
drivers find freedom of operation.
< 10 < 10
B Very good operation. Many drivers begin to
feel somewhat restricted within platoons of
vehicles. This represents stable flow. An
approach to an intersection may occasionally be
fully utilized and traffic queues start to form.
>10 and < 20 >10 and < 15
C Good operation. Occasionally drivers may have
to wait more than 60 seconds, and back‐ups
may develop behind turning vehicles. Most
drivers feel somewhat restricted
>20 and < 35 >15 and < 25
D Fair operation. Cars are sometimes required to
wait more than 60 seconds during short peaks.
There are no long‐standing traffic queues.
>35 and < 55 >25 and < 35
E Poor operation. Some long‐standing vehicular
queues develop on critical approaches to
intersections. Delays may be up to several
minutes.
>55 and < 80 >35 and < 50
F Forced flow. Represents jammed conditions.
Backups form locations downstream or on the
cross street may restrict or prevent movement of
vehicles out of the intersection approach lanes;
therefore, volumes carried are not predictable.
Potential for stop and go type traffic flow.
> 80 > 50
Source: Highway Capacity Manual, Special Report 209, Transportation Research Board, Washington,
DC, 2000.
The following table describes the various capacity values assigned for differing roadway sizes
and levels of service. Capacity is generally defined as the number of vehicles that may pass over
a section of roadway in a given time period under prevailing conditions. However, capacities of
roadways are most restricted by intersection design and operation, which are discussed further
below. Typically, the PM peak hour is the heaviest traffic flow of the day. It should be noted that
in the planning area the peak hour operations are spread across a greater time period.
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Table III-45
City Roadway Classifications
Level of Service Volumes/Capacity Values
(Average Daily Trips – ADT)
Facility
Type
Lane
Config-
uration
LOS A
(60%)
LOS B
(70%)
LOS C
(80%)
LOS D
(90%)
LOS E
(100%)
LOS F
Local 2U <5,490 5,490 -
6,390
6,390 -
7,290
7,290 -
8,190
8,190 -
9,000 >9,000
Collector 2U <8,540 8,540 -
9,940
9,940 -
11,340
11,340 -
12,740
12,740 -
14,000 >14,000
Modified
Secondary 2D <11,590 11,590 -
13,490
13,490 -
15,390
15,390 -
17,290
17,290 -
19,000 >19,000
Secondary 4U <17,080 17,080 -
19,880
19,880 -
22,680
22,680 -
25,480
25,480 -
28,000 >28,000
Primary 4D <25,560 25,560 -
29,800
29,800 -
34,080
34,080 -
38,340
38,340 -
42,600 >42,600
Major 6D <36,600 36,600 -
42,700
42,700 -
48,800
48,000 -
54,900
54,900 -
61,000 >61,000
Augmented
Major 8D <45,600 45,600 -
53,200
53,200 -
60,800
60,800 -
68,400
68,400 -
76,000 >76,000
Source: La Quinta General Plan Traffic Impact Analysis, 2012 and Highway Capacity Manual,
2010.
Regional and Local Traffic Model
As noted in the introduction to this discussion, the La Quinta General Plan Traffic Analysis
Model (LQTAM) is a highly detailed, fine-grained level of analysis that has been developed in a
manner consistent with the Riverside County Transportation Analysis Model (RivTAM), which
is also the basis for regional transportation planning coordinated by CVAG. In addition to
providing modeling consistency from the local through the regional level, RivTAM minimizes
the time and effort needed to maintain and update this transportation planning and management
tool.
Specifically, the La Quinta traffic model consists of a traditional four step modeling process
including (1) trip generation, (2) trip distribution, (3) mode split (choice), and (4) traffic
assignment. Two model scenarios were included in the La Quinta TAM, namely the base year
2009 and the forecast year 2035. To work from a more refined level, the traffic modeling process
begins with defining the traffic analysis zones (TAZ) and the roadway network, establishing
efficient/logical traffic routes, collecting land use and socio-economic data on each TAZ,
calculating trip generation in each TAZ, distributing traffic and its assignment to individual road
segments. Each major component of the La Quinta model is described below.
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Zone and Network System
The regional traffic model divides the General Plan planning area from just a few TAZs to a
detailed modeling area of 123 TAZs following RivTAM zone boundaries, General Plan land use
boundaries, digital street centerlines and other GIS data, thereby greatly increasing the detail of
the analysis. Traffic volumes have been generated for each TAZ based upon the mix and acreage
of each land use in each TAZ, with land uses being factored into the model as either trip
“productions” or “attractions.” Traffic from outside the planning area is based upon the larger
scale, regional RivTAM TAZ structure, and interacts with planning area traffic at various cordon
stations located along planning area boundaries. A forecast of traffic volumes is produced by the
model and is based upon the TAZ system.
The model then loads the traffic onto the roadway network, and approximates how actual traffic
enters and utilizes the local roadway system. The roadway network focuses on major streets and
generally excludes local streets. Traffic generated in each zone is placed on the network at
primary connectors, called “centroids," identified by the model.
The model also considers a variety of roadway characteristics, including the type of roadway,
free-flow speeds, and hourly travel per lane. Likely network operations are also refined by speed
adjustments developed to increase sensitivity to roadway constraints (Please refer to the La
Quinta General Plan TIA for an illustration of the TAZ’s and a complete breakdown of the
various land uses within each TAZ).
The current land use patterns were used as the basis for the La Quinta General Plan TAZ system.
The TAZ pattern is tailored specifically to the City and planning area in order to provide the
most accurate data possible. The model distributes the projected volume of traffic that will occur
due to the build out of the General Plan land use plan and factors growth in other areas of the
Valley. From this information the design requirements to maintain acceptable traffic flows are
determined.
Depending upon the level of land use integration within each TAZ, traffic generated within each
TAZ may stay within the TAZ or cross TAZ boundaries, which typically requires travel on a
higher capacity street such as a collector or arterial roadway. TAZs are selected planning
subareas typically defined by major roadways. The interaction of land uses within each TAZ is a
measure of land use efficiency, depending on the degree to which development generates local
traffic or requires extended use of the arterial roadway network.
Trip Generation
Trip generation provides the raw data for traffic modeling. Vehicle trips generated within each
TAZ of the modeling area are based on land use data as designated by existing land uses and the
General Plan Land Use Element. The RivTAM model first analyses sixteen (16) "land use to
employment" conversion rates, ranging from very low density residential to commercial, and
also including industrial, institutional and open space uses.
The General Plan traffic analysis also uses eleven (11) separate “home-based” trip definitions
and two “non-home-based” definitions. Some trips originate from or are destined to the home,
while other trips are between non-home destinations, such as from work to lunch or the doctor’s
office, or from dinner to a movie.
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The RivTAM and La Quinta models were used to derive the average trip generation rates per the
various land uses, and were modified for City-specific application. The total number of vehicle
trips produced in or attracted to a geographic area is directly related to the land use and
demographic variables found in each TAZ. The model estimates the number of peak season
vehicle trips that will be produced on an average weekday for each analysis zone.
Trip Distribution and Traffic Assignment
For each of the 123 TAZs developed for the La Quinta model, the volume of traffic has been
calculated and broken down and the trip generation associated with each has been calculated.
Once accomplished, the trip distribution and assignment functions of the City traffic model were
then implemented. Next a general directional distribution of these trips was made and then
finally assigned to specific streets. As mentioned, trips are either attractions or productions; that
is, land uses are either drawing trips into the TAZ or are exporting trips. Typically, this
distribution of trips is accomplished using a “gravity distribution model”, based on the formula
that the distribution of trips is proportional to the “attractiveness” of the land use and the distance
(or travel time) from the point of trip production. Each type of trip or trip purpose has its own
specific travel time distribution function or curve.
Traffic is assigned to the roadway network over distinct time periods and to specific route paths
of the various trip interchanges between TAZs identified in the trip distribution process. The end
result of these forecasts of daily traffic volumes yields the aggregate assignment of trips to
roadways between and connecting TAZs throughout the City and planning area. The traffic
assignment process for the General Plan traffic model has also been adapted from procedures
used in the Valley-wide RivTAM model.
1. Existing Conditions
Within the urbanized and developing areas of the City and planning area, the roadway network
has been constructed and is conveying traffic. The following briefly discusses the major regional
and local roadways serving the planning area, as well as conditions at major intersections within
the City. While Levels of Service for roadway links or segments are discussed, Levels of Service
at intersections are a more meaningful measure of actual roadway operating conditions. The
tables that follow provide additional information on existing roadway link and intersection
conditions in the City and General Plan study area. It should also be kept in mind that operating
conditions are gauged against current and not ultimate levels of street and intersection
improvements.
Regional Roadways
Those roadways that provide intra-Valley and super regional connections are herein termed
regional roadways. They include State Highways 111 and 86, and U.S. Interstate-10. State
Highway 111 begins at its juncture with Interstate-10 three miles west of Palm Springs and
extends southeast to Brawley in the Imperial Valley. Highway 86 connects the planning area and
other parts of the Coachella Valley with Imperial County and Mexico. Interstate-10 connects the
Los Angeles region with Arizona and other cities and states to the east. Together, these important
roadways provide regional, interstate and international connections for the City and the
Coachella Valley.
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State Highway 111
State Highway 111 has been built along the old Bradshaw Trail, which extended along the base
of the Santa Rosa Mountains. Highway 111 is an important intra-regional connector serving the
local cities. Portions of this route have been relinquished by the State to local cities, which have
agreed to accept ownership, maintenance, operation, and liability for their respective roadway
segments. Some through-traffic appears to have moved north to Fred Waring Drive and I-10 in
response to congestion along Highway 111. However, the La Quinta traffic model shows that
approximately 58 percent of traffic on Highway 111 does not originate in and is not destined for
locations within the City, and is simply passing through along this roadway. In the City, this
roadway is built out to six-lanes divided. Highway 111 serves a wide mix of commercial land
uses. Existing traffic volumes range from approximately 29,726 VPD east of Washington Street
and approximately 38,037 VPD west of Jefferson Street. Intersections with Highway 111 are
currently operating at Level of Service (LOS) C, with the exception of its intersection with
Washington Street (LOS D in 2010) and mid-block segments operate at LOS C or better. Sunline
bus service is available along its length and this roadway serves as a designated truck route.
Highway 86S Expressway
Highway 86S is a semi-limited access expressway and an intra-regional arterial highway
providing indirect but important access to the eastern portion of the planning area. Highway 86S
is a northwest-southeast trending expressway designated as a “Freeway” in the County of
Riverside General Plan, with a variable right-of-way. In the vicinity of the planning area,
Highway 86S has been improved as a four-lane high volume roadway with a wide median island
and with slip and turn lanes at major surface crossroads. Existing traffic volumes range from
approximately 20,000 VPD north of Avenue 60 to approximately 12,900 VPD south of Avenue
62. Due to high future volumes, the current at-grade intersection of SR-86 and Avenue 62 has
been planned for expansion to provide a grade-separated facility utilizing a partial cloverleaf
design.
U.S. Interstate-10
US Interstate-10 is currently built as a six to eight-lane divided freeway accessed from both loop
and diamond interchanges spaced a minimum of one mile apart. I-10 provides essential inter-city
and inter-regional access, and is also a critical part of the local road network moving people and
goods into and out of the Valley. Direct City access to I-10 is currently provided through
interchanges with Washington Street and Jefferson.
Local Major Roadways
The City has developed and maintains an extensive arterial roadway network, which, in addition
to the regional facilities serving the community, also serves both local and inter-city traffic. The
City road network has been built essentially along a north-south grid, with interconnections with
major arterials passing through adjacent jurisdictions. The location of trip attractors along these
roads or the convenience they provide in traversing the City varies with each road.
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Washington Street
Washington Street, oriented in a north-south direction, has a variable roadway with and consists
of three lanes in each direction through the majority of the planning area. It is currently classified
as a Major Arterial. Current traffic volumes range from approximately 23,434 to 40,633 VPD.
Washington Street provides access to State Highway 111 and to Interstate 10 (I‐10) north of the
city limits. Intersections with Washington Street are currently operating at Level of Service
(LOS) C or better, with the exception of its intersection with Highway 111 (LOS D in 2010).
Mid-block segments operate at LOS C or better. Bicycles are accommodated and Sunline bus
service is also available on the fully improved segments of this roadway.
Eisenhower Drive
Eisenhower Drive is oriented in an east-west direction at Washington Street, and transitions to a
north-south roadway at Avenue 50. Eisenhower Drive consists of two lanes in each direction and
is classified as a Primary Arterial. Current traffic volumes range from 10,000 to 12,000 VPD.
Intersections with Eisenhower Drive are operating at LOS C or better and mid-block segments
operate at LOS A. Bicycles and golf carts are accommodated on the fully improved segments of
this roadway.
Avenida Bermudas
Avenida Bermudas is oriented in a north-south direction and consists of two lanes in each
direction, extending from Calle Tampico on the north to the top and along the east side of the
cove on the south. This roadway is classified as a Secondary Arterial with traffic volumes
ranging from 3,400 to 9,200 VPD. Avenida Bermudas provides a variable paved section ranging
from four lanes in the Village area to two lanes near the top of the cove. Bicycles and buses are
accommodated on the fully improved segments of this roadway.
Adams Street
Adams Street is oriented in a north-south direction and consists of two lanes in each direction. It
is classified as a Secondary Arterial and has been built as a Primary Arterial between Highway
111 and Avenue 48, with traffic volumes ranging from 12,000 to 14,000 VPD. Its intersections
all currently operate at LOS C and mid-block segments operate at LOS A. Bicycles and buses are
accommodated on the fully improved segments of this roadway. A bridge to carry Adams Street
over the Coachella Valley Stormwater Channel (Whitewater River) is expected to be completed
in 2013.
Dune Palms Road
Dune Palms Road is oriented in a north-south direction and consists of two lanes in each
direction between Fred Waring Drive and Westward Ho Drive, one lane in each direction
between Westward Ho Drive and Highway 111, and two lanes in each direction between
Highway 111 and Avenue 48. Dune Palms Road is classified as a Secondary Arterial. Current
traffic volumes range from 10,000 to 12,000 VPD. Intersections with Dune Palms Road are
operating at LOS C and mid-block segments operate at LOS A. Bicycles are accommodated on
the fully improved segments of this roadway. There is an at-grade crossing of the Whitewater
River with long-term plans for at least a low-flow crossing at this location.
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Jefferson Street
Jefferson Street is oriented in a north-south direction and consists of three lanes in each direction.
It is classified as a Major Arterial north of Avenue 54 and as a Modified Secondary Arterial
between Avenue 58 and Avenue 62. Jefferson Street provides access to State Highway 111,
southern parts of the City and to Interstate 10 (I‐10) north of city limits. Current traffic volumes
range from 12,000 to 27,000 VPD. Intersections with Jefferson Street are operating at LOS C or
better; the roundabout at Avenue 52 is operating at LOS A. Mid-block segments operate at LOS
A. Bicycles are accommodated on the fully improved segments of this roadway.
Madison Street
Madison Street is oriented in a north-south direction and consists of one lane in each direction
between Avenue 50 and Avenue 54 and two lanes in each direction between Avenue 54 and
Avenue 60. Madison Street is classified as a Primary Arterial between Avenue 50 and Avenue
58, as a Secondary Arterial between Avenue 58 and Avenue 60, and as a Modified Secondary
Arterial between Avenue 60 and Avenue 62. Current traffic volumes range from 3,300 to 9,200
VPD. Most intersections with Madison Street are operating at LOS A or B, with its intersection
with Avenue 50 operating at LOS C in the AM and LOS D in the PM peak hours. Mid-block
segments operate at LOS A. Bicycles are accommodated on the fully improved segments of this
roadway.
Monroe Street
Monroe Street is oriented in a north-south direction and consists of one lane in each direction. It
is classified as a Primary Arterial between Avenue 52 and Avenue 60 and as a Secondary
Arterial between Avenue 60 and Avenue 62. Monroe Street provides access to State Highway
111 and to Interstate-10 north of city limits. Current traffic volumes range from 2,500 to 3,100
VPD. Intersections with Monroe Street are operating at LOS B or better, with mid-block
segments operating at LOS A. Bicycles are accommodated on the fully improved segments of
this roadway.
Jackson Street
Jackson Street is oriented in a north-south direction and consists of one lane in each direction. It
is classified as a Primary Arterial. Jackson Street is located in the City’s Sphere and provides
access to State Highway 111 and to Interstate-10 north of city limits. Current traffic volumes
range from 1,700 to 3,300 VPD. In the planning area, intersections with Jackson Street are
expected to operate at LOS B or better, with mid-block segments operating at a LOS A. Bicycles
are accommodated on the fully improved segments of this roadway.
Van Buren Street
Van Buren Street is oriented in a north-south direction and consists of one lane in each direction.
It is classified as a Primary Arterial between Avenue 52 and Avenue 60 and as a Secondary
Arterial between Avenue 60 and Avenue 62. Van Buren Street is located in the City’s Sphere. In
the planning area, intersections with Jackson Street are expected to operate at LOS B or better,
with mid-block segments operating at a LOS A. No alternative modes of travel are
accommodated on the fully improved segments of this roadway.
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Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
III-209
Harrison Street
Harrison Street is oriented in a north-south direction and consists of one lane in each direction. It
is classified as a Major Arterial. Harrison Street is located in the City’s Sphere. In the planning
area, intersections with Jackson Street are expected to operate at LOS B or better, with mid-
block segments operating at a LOS A. No alternative modes of travel are accommodated.
Fred Waring Drive
Fred Waring Drive (Avenue 44) is oriented in an east-west direction and consists of three lanes
in each direction between Washington Street and Adams St and between Dune Palms Road and
Jefferson Street. Between Adams Street and Dune Palms Road, Fred Waring Drive consists of
two lanes in the eastbound direction and one lane in the westbound direction. Fred Waring Drive
is classified as a Primary Arterial. Current traffic volumes are approximately 24,500 VPD.
Intersections with Fred Waring Drive are operating at LOS C, with mid-block segments
operating at LOS A. Bicycles are accommodated . on the fully improved segments of this
roadway.
Miles Avenue
Miles Avenue is oriented in an east-west direction and consists of two lanes in each direction. It
is classified as a Primary Arterial. Current traffic volumes between Washington Street and
Adams Street are approximately 24,500 VPD. Intersections with Miles Avenue are currently
operating at LOS C, with mid-block segments operating at LOS A. Bicycles and a bus route are
accommodated on the fully improved segments of this roadway.
Avenue 48
Avenue 48, oriented in an east-west direction, consists of two lanes in each direction, and is
classified as a Primary Arterial. Current traffic volumes between Washington Street and Madison
Street range from 9,600 VPD east of Jefferson Street to about 18,400 VPD east of Dune Palms
Road. Intersections with Avenue 48 are currently operating at LOS C, with mid-block segments
operating at LOS A. Bicycles are accommodated along on the fully improved segments of this
roadway.
Avenue 50
Avenue 50, oriented in an east-west direction, consists of two lanes in each direction, and is
classified as a Primary Arterial. Current traffic volumes between Washington Street and Madison
Street are average 9,800 VPD. Intersections with Avenue 48 are currently operating at LOS C,
with the exception of the Avenue 50 intersection with Washington Street, which is operating at
LOS D. Mid-block segments are operating at LOS A. Bicycles are accommodated along on the
fully improved segments of this roadway.
Calle Tampico
Calle Tampico, oriented in an east-west direction, consists of two lanes in each direction, and is
classified as a Primary Arterial west of Washington Street. East of Washington Street, Calle
Tampico consists of one lane in each direction and is classified as a Collector Street. Current
traffic volumes range from 5,300 VPD west of Avenida Bermudas and about 10,000 VPD west
of Washington Street. Intersections with Avenue 48 are currently operating at LOS C, with the
exception of the Avenue 50 intersection with Washington Street, which is operating at LOS D.
Terra Nova/La Quinta General Plan EIR
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III-210
Mid-block segments are operating at LOS A. Bicycles, golf carts and buses are accommodated
along on the fully improved segments of this roadway.
Avenue 52
Avenue 52 is oriented in an east-west direction and consists of two lanes in each direction
between Avenida Bermudas and Jefferson Street. Between Jefferson Street and Monroe Street,
Avenue 52 consists of two eastbound lanes and one westbound lane. Between Monroe Street and
Jackson Street, Avenue 52 consists of one eastbound lane and two westbound lanes. Avenue 52
is classified as a Primary Arterial throughout the City and the City’s Sphere. Current traffic
volumes range from 7,200 VPD west of Monroe Street to about 16,100 VPD west of Washington
Street. Intersections with Avenue 52 are currently operating at LOS C or better, with the
exception of the Avenue 52 intersection with Avenida Bermudas, which is operating at LOS D.
Mid-block segments are operating at LOS A. Bicycles, golf carts and buses are accommodated
along on the fully improved segments of this roadway.
Avenue 54
Avenue 54 is an east-west street consisting of two lanes in each direction between Jefferson
Street to east of Monroe Street. East of Monroe Street, Avenue 54 is a variable roadway with two
westbound lanes and one eastbound lane. East of Monroe Street, Jefferson Street provides one
lane in each direction. Avenue 54 is classified as a Primary Arterial between Jefferson Street and
Monroe Street and is classified as a Secondary roadway between Monroe Street and Van Buren
Street. Current traffic volumes are 7,200 VPD between Jefferson and Madison Streets.
Intersections with Avenue 52 are currently operating at LOS C or better, with the exception of
the Avenue 52 intersection with Avenida Bermudas, which is operating at LOS D. Roadway
segments are operating at LOS A. Bicycles, golf carts and buses are accommodated on the fully
improved segments of this roadway.
Avenue 56 (Airport Boulevard)
Airport Boulevard or Avenue 56 is an east-west street extending east of Madison Street, and
consisting of two lanes in each direction between Jefferson Street Monroe Street. East of Monroe
Street, Avenue 56 is a two-lane roadway. Avenue 56 is classified as a Primary Arterial. Current
traffic volumes are 1,900 VPD east of Madison Street. Intersections are currently operating at
LOS C or better, with the exception of the Avenue 52 intersection with Avenida Bermudas,
which is operating at LOS D. Roadway segments are operating at LOS A. Bicycles, golf carts
and buses are accommodated on the fully improved segments of this roadway.
Avenue 60
Avenue 60 is an east-west street extending from the US Bureau of Reclamation Dike 4, eastward
to the Coachella Valley Stormwater Channel. Local two lane segments also occur between the
stormwater channel and the Highway 111/86S Expressway corridor, east of which it continues as
a local street serving primarily agriculture. Avenue 60 is designated as a Secondary roadway
from Madison Street on the west to Monroe Street, east of which it is classified as a Primary
Arterial. Avenue 60 is currently improved as a two-lane roadway, except between Madison
Street and Monroe Street where it provides one eastbound through lane, two westbound through
lanes, median islands and turn lanes. Current traffic volumes are 3,000 VPD east of Madison
Terra Nova/La Quinta General Plan EIR
Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
III-211
Street and 1,500 east of Monroe Street. Bicycles are accommodated on the fully improved
segments of this roadway.
Avenue 62
Much of the southern boundary of the General Plan planning area is east-west running Avenue
62, which is partially improved from USBR Dike No. 4 eastward to the east end of the Valley,
crossing the stormwater channel, as well as Highway 111 and the 86S Expressway. Avenue 62 is
classified as a Modified Secondary west of Monroe Street extended), and is classified a
Secondary east of Monroe Street. Current traffic volumes are 1,000 VPD west of Monroe Street
and ranging from 500 to 800 VPD east of Monroe Street. No alternative modes of travel are
accommodated on this roadway.
The following exhibit shows the existing average daily traffic volumes on the major roadways in
the General Plan study area.
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General Plan Roadway Classifications
Each major roadway in the planning area has been assigned a specific design classification based
upon existing and projected traffic demands generated by build out of the General Plan. The need
for and appropriateness of each classification has been based upon modeled future traffic
volumes and overall community design goals set forth in the General Plan. Each of the
classifications corresponds with the street cross sections illustrated in the General Plan
Circulation Element. Certain refinements or adjustments may be required when securing right-
of-way and constructing improvements at specific locations, and provisions for such adjustments
are included in the Circulation Element.
Existing Daily Traffic Volumes
As a direct result of the analysis conducted on existing traffic and roadway conditions, and on
projections of future traffic resulting from General Plan build out, the roadway classification
system has been developed and assigned to existing and future roads. This process has also taken
into consideration special issues of concern and opportunities to enhance community circulation.
Table III-46 lists these General Plan roadways and also provides information on existing daily
volumes, number of lanes, roadway capacity, volume to capacity (V/C) ratios, and LOS.
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Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
III-216
Table III-46
Existing Daily Volumes and Capacity Summary
General Plan Study Area
Roadway Link Existing
ADT
Roadway
Designation
Existing
Number
of
Lanes
Existing
Capacity
Existing
V/C
Ratio -
LOS
Washington St
Ave 42 to Fred Waring Dr 37,426 Major 6 59,300 0.63 – B
Fred Waring Dr to Miles Ave 40,633 Major 6 59,300 0.69 – B
Miles Ave to Hwy 111 32,915 Major 6 59,300 0.56 – A
Hwy 111 to Ave 48 36,710 Major 6 59,300 0.62 – B
Ave 48 to Eisenhower Dr 33,465 Major 6 59,300 0.56 – A
Eisenhower Dr to 600’ north of Ave 50 27,129 Major 6 59,300 0.46 – A
600’ north of Ave 50 to Ave 50 27,129 Major 5 47,500* 0.57 – A
Ave 50 to Calle Tampico 23,434 Major 6 59,300 0.40 – A
Eisenhower Dr
Washington St to Ave 50 12,0131 Primary 4 41,400 0.29 – A
Avenue 50 to Calle Tampico 9,9751 Primary 4 41,400 0.24 – A
Avenida Bermudas
Calle Tampico to Ave 52 3,3881 Secondary 4 28,000 0.12 – A
Ave 52 to Calle Durango 9,2751 Secondary 4 28,000 0.33 – A
Adams St
Westward Ho Dr to Hwy 111 13,724 Secondary 4 41,400 0.33 – A
Hwy 111 to Ave 48 12,035 Secondary 4 41,400 0.29 – A
Dune Palms Rd
Westward Ho Dr to Hwy 111 9,282 Secondary 2 19,000 0.49 – A
Hwy 111 to Ave 48 8,373 Secondary 4 41,400 0.20 – A
Jefferson St
Country Club Rd to Fred Waring Dr 20,913 Major 6 59,300 0.35 – A
Fred Waring Dr to Miles Ave 23,764 Major 6 59,300 0.40 – A
Westward Ho Dr to Hwy 111 27,112 Major 6 59,300 0.46 – A
Hwy 111 to Ave 48 26,889 Major 6 59,300 0.45 – A
Ave 48 to Ave 50 27,133 Major 6 59,300 0.46 – A
Ave 50 to Ave 52 16,169 Major 6 59,300 0.27 – A
Ave 52 to Ave 54 12,399 Major 6 59,300 0.21 – A
Madison St
Ave 50 to Ave 52 5,664 Primary 2 14,000 0.40 – A
Ave 54 to Airport Blvd 9,219 Primary 4 41,400 0.22 – A
Airport Blvd to Ave 58 6,348 Primary 4 41,400 0.15 – A
Ave 58 to Ave 60 3,341 Secondary 4 41,400 0.08 – A
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Table III-46
Existing Daily Volumes and Capacity Summary
General Plan Study Area
Roadway Link Existing
ADT
Roadway
Designation
Existing
Number
of
Lanes
Existing
Capacity
Existing
V/C
Ratio -
LOS
Monroe St
Ave 52 to Ave 54 3,147 Primary 2 14,000 0.22 – A
Ave 54 to Airport Blvd 2,532 Primary 2 14,000 0.18 – A
Jackson St
Ave 54 to Airport Blvd 3,338 Primary 2 14,000 0.24 – A
Airport Blvd to Ave 58 2,326 Primary 2 14,000 0.17 – A
Ave 58 to Ave 60 1,734 Primary 2 14,000 0.12 – A
Ave 60 to Ave 62 1,569 Primary 2 14,000 0.11 – A
Van Buren St
Ave 52 to Ave 54 4,663 Primary 2 14,000 0.33 – A
Ave 54 to Airport Blvd 3,346 Primary 2 14,000 0.24 – A
Airport Blvd to Ave 58 1,472 Primary 2 14,000 0.11 – A
Ave 58 to Ave 60 1,176 Primary 2 14,000 0.08 – A
Ave 60 to Ave 62 1,017 Secondary 2 14,000 0.07 – A
Harrison St
Airport Blvd to Ave 58 6,690 Major 2 14,000 0.48 – A
Fred Waring Dr (Ave 44)
Washington St to Adams St 24,492 Primary 6 59,300 0.41 – A
Miles Ave
Washington St to Adams St 9,828 Primary 4 41,400 0.24 – A
Hwy 111
Washington St to Adams St 29,726 Major 6 59,300 0.50 – A
Adams St to Dune Palms Rd 31,348 Major 6 59,300 0.53 – A
Dune Palms Rd to Jefferson St 38,037 Major 6 59,300 0.64 – B
Ave 48
Washington St to Adams St 12,903 Primary 4 41,400 0.31 – A
Dune Palms Rd to Jefferson St 18,364 Primary 4 41,400 0.44 – A
Ave 50
Washington St to Jefferson St 9,663 Primary 4 41,400 0.23 – A
Jefferson St to Madison St 9,990 Primary 4 41,400 0.24 – A
Calle Tampico
Eisenhower Dr to Avenida Bermudas 5,3501 Primary 41,400 0.13 – A
Avenida Bermudas to Washington St 10,0631 Primary 41,400 0.24 – A
Ave 52
Avenida Bermudas to Washington St 16,133 Primary 4 41,400 0.39 – A
Washington St to Jefferson St 13,529 Primary 4 41,400 0.33 – A
Jefferson St to Madison St 10,306 Primary 2 19,000 0.54 – A
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Table III-46
Existing Daily Volumes and Capacity Summary
General Plan Study Area
Roadway Link Existing
ADT
Roadway
Designation
Existing
Number
of
Lanes
Existing
Capacity
Existing
V/C
Ratio -
LOS
Madison St to Monroe St 7,238 Primary 2 19,000 0.38 – A
Ave 54
Jefferson St to Madison St 8,386 Primary 4 41,400 0.20 – A
Airport Blvd
Madison St to Monroe St 1,893 Primary 4 41,400 0.05 – A
Ave 58
Madison St to Monroe St 2,188 Secondary 4 41,400 0.05 – A
Monroe St to Jackson St 1,554 Secondary 2 14,000 0.11 – A
Ave 60
Madison St to Monroe St 3,067 Secondary 2 19,000 0.16 – A
Monroe St to Jackson St 855 Primary 2 14,000 0.06 – A
Ave 62
Madison St to Monroe St 1,0251 Modified
Collector 2 14,000 0.07 – A
Monroe St to Jackson St 804 Secondary 2 14,000 0.06 – A
Jackson St to Van Buren St 557 Secondary 2 14,000 0.04 – A
Van Buren St to Harrison St 866 Secondary 2 14,000 0.06 – A
As shown in the above table, the roadway segments analyzed are currently operating at LOS A,
with the exception of three segments of Washington Street and one segment of Highway 111 that
are operating at LOS B. Clearly, all analyzed roadway segments are currently operating well
within the acceptable levels of service.
Existing Operating Conditions at Major Intersection
As noted above, a total of thirty-seven (37) intersections were analyzed as part of the General
Plan update. As with the analysis of existing conditions for various roadway segments, the
intersection analysis also evaluated intersection volumes and levels of service for the peak
season period. The following Table III-47 sets forth this information.
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Table III-47
Existing Peak Hour Intersection LOS
Peak Season
Intersection Traffic
Control
AM Peak
Hour
PM Peak
Hour
LOS Delay
(Sec) LOS Delay
(Sec)
1. Washington St & Fred Waring Dr Signal C 34.9 C 34.1
2. Washington St & Miles Ave Signal C 29.2 C 28.0
3. Washington St & Channel Dr Signal B 18.2 C 25.3
4. Washington St & Hwy 111 Signal D 35.3 D 42.3
5. Washington St & Ave 48 Signal C 32.3 C 25.1
6. Washington St & Eisenhower Dr Signal C 23.7 C 20.7
7. Washington St & Ave 50 Signal C 30.3 C 25.6
8. Washington St & Calle Tampico Signal C 24.7 C 25.4
9. Washington St & Ave 52 Signal C 20.6 C 23.9
10. Eisenhower Dr & Calle Tampico Signal C 24.1 C 27.2
11. Avenida Bermudas & Ave 52 Signal D 38.6 C 26.3
12. Adams St & Fred Waring Dr Signal C 34.6 C 28.8
13. Adams St & Miles Ave Signal C 31.4 C 30.8
14. Adams St & Hwy 111 Signal C 29.0 C 28.7
15. Adams St & Ave 48 Signal C 29.6 C 27.7
16. Dune Palms Rd & Fred Waring Dr Signal C 25.4 C 20.2
17. Dune Palms Rd & Miles Ave Signal C 31.9 C 31.0
18. Dune Palms Rd & Westward Ho Dr Signal C 30.8 C 31.4
19. Dune Palms Rd & Hwy 111 Signal C 30.3 C 26.6
20. Dune Palms Rd & Ave 48 Signal C 24.1 C 25.9
21. Jefferson St & Fred Waring Dr Signal C 31.2 C 30.6
22. Jefferson St & Hwy 111 Signal C 30.3 C 30.8
23. Jefferson St & Ave 48 Signal C 32.5 C 31.4
24. Jefferson St & Ave 49 Signal C 23.9 C 20.1
25. Jefferson St & Ave 50 Signal C 32.7 C 32.6
26. Jefferson St & Ave 52 Roundabout A 7.5 A 7.0
27. Jefferson St & Ave 54 AWSC B 11.6 B 11.6
28. Madison St & Ave 50 AWSC C 17.1 D 32.4
29. Madison St & Ave 52 AWSC B 12.1 B 13.0
30. Madison St & Ave 54 AWSC B 10.8 B 11.5
31. Madison St & Ave 58 AWSC A 8.4 A 9.1
32. Madison St & Ave 60 AWSC A 8.0 A 9.1
33. Monroe St & Ave 52 AWSC B 13.8 B 14.4
34. Monroe St & Ave 54 AWSC B 10.2 B 10.6
35. Monroe St & Ave 58 AWSC A 7.7 A 8.5
36. Monroe St & Ave 60 AWSC A 7.9 A 8.1
37. Monroe St & Ave 62 AWSC A 7.5 A 7.4
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During the peak season, and as shown in the above table, all but four of the 37 study
intersections operate at LOS C or better. The intersection of Washington Street/Highway 111
operates at LOS D, very near LOS C, during the a.m. peak hour. During the p.m. peak hour, this
intersection operates at a slightly worse delay during peak season conditions, but remains at LOS
D. The intersection of Avenida Bermudas/Avenue 52 operates at LOS D and very near LOS C,
during the a.m. peak hour. The intersection of Madison Street/Avenue 50 operates at LOS D
during only the p.m. peak hour. This intersection is all-way stop-controlled, therefore LOS
ranges are smaller than those applied to signalized intersections. All study intersections are
operating at acceptable levels of service (LOS D or better).
All-Weather Access
Major drainages that affect roadway access both within the City and the planning area include
the Whitewater River (aka Coachella Valley Stormwater Channel east of Washington Street) and
the La Quinta Evacuation Channel. The Whitewater River is the principal drainage affecting all-
weather access in the City. Current all-weather crossings exist on Washington Street, Eisenhower
Drive, Adams Street and Jefferson Street. Dune Palms Drive is currently a low-flow crossing.
Future all-weather crossings are also planned for the southern extensions of Jefferson Street over
the Dike 2 flood protective levee and Madison Street over the Dike 4 levee. All-weather access
and roadway capacity are also affected by stormwater runoff, which is frequently conveyed by
local streets into dedicated surface and sub-surface stormwater facilities. Areas of inadequate
drainage can result in on-road ponding, unsafe conditions, and reduced accessibility and
capacity.
SunLine Transit Agency and Public Transportation
The provider of public transit service within La Quinta and the Coachella Valley is the SunLine
Transit Agency. In addition to SunLine’s fleet of new buses powered by compressed natural gas
and other clean-burning fuels, SunLine is also integrating other innovative technologies and fuels
into the local public transit system. In 2002 SunLine introduced a bus powered entirely by zero-
emission fuel cell technology.
Local and Supplemental Bus Service
The City and Sphere of Influence are directly served by two bus routes, Line 111 and Line 70.
Line 111 runs along Highway 111 from Indio to Palm Springs and is a main trunk line in the
SunLine system. Line 70 extends from the south end of the La Quinta Cove, north to and east
along Avenue 47, then north along Adams Street where it turns west to Washington Street and
north to Country Club Drive.
The SunDial is a Valley-wide, ADA-compliant service providing curb-to-curb next day service
that is wheelchair accessible. Sunline is putting into service a new "Riverside Commuter Express
Route 210" service that will run between Palm Desert and Riverside. This service will be an
expansion of existing the RTA CommuterLink Route 210 service between Banning and
Riverside, with local stops to include Thousand Palms/I-10 area, Cabazon and other communities
to the west.
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Air Transportation
La Quinta and the Coachella Valley region are served by three airports, each of which is briefly
described below:
Palm Springs International Airport
Palm Springs International Airport is located west of Gene Autry Trail and north of Ramon Road
in the City of Palm Springs, and is the primary air transportation link for the Coachella Valley.
The airport is classified in the National Plan of Integrated Airport Systems (NPIAS) as a long-
haul commercial service airport. It is capable of supporting non-stop commercial service to
destinations over 1,500 miles and is classified as a small hub air passenger airport based upon the
percentage of national airline enplanements it supports. Airport enplanements are projected to
reach approximately 809,256 by the year 2015
Jacqueline Cochran Regional Airport
The Jacqueline Cochran Regional Airport is located immediately east of the City’s Sphere of
influence, on the east side of Harrison Street, between Avenue 56 (Airport Boulevard) and
Avenue 62. Annual aircraft operations at Jacqueline Cochran Regional Airport were estimated at
65,000 in 2002, none of which were of a commercial nature. The airport's master plan projects
this activity to reach some 110,000 operations by 2022 and to continue to grow along with the
urbanization of the Coachella Valley. While commercial passenger services are anticipated there
is no projected date when these might be offered.
Bermuda Dunes Airport
Bermuda Dunes Airport is a General Aviation Airport located on 100± acres adjacent and
parallel to the Union Pacific Railroad/ Interstate-10 corridor, approximately three miles north of
the City limits. The airport is bounded on the north by Country Club Drive, on the south by
Avenue 42, on the west by Adams Street and on the east by Jefferson Street. A total of
approximately 25,332 operations occur each year at this airport, of which about 6.6% are
business jets. The expansion of facilities at this airport is essentially precluded by surrounding
development. Annual maximum capacity is estimated at 75,000 operations per year.
Railway Facilities
Rail lines of the Union Pacific Railroad (UPRR) are located north and east of the La Quinta
planning area. Rail freight service is provided to the Coachella Valley by the Union Pacific
Railroad, with freight transfer facilities located in Indio and Coachella. There is also Amtrak
service to Indio and Palm Springs. These rail facilities carry approximately 40 trains per day,
almost all of which are freight. The County and local jurisdictions are exploring possible future
access to Union Pacific Rail lines for future passenger and freight service access.
2. Project Impacts
The consequences of General Plan build out, and within the context of continued development
outside the planning area, have been evaluated for the 63 major roadway segments and 37
intersections that have been analysed. Based on this analysis, the proposed General Plan Land
Use Plan is projected to generate a total of approximately 635,905 average daily trips. Of these,
Terra Nova/La Quinta General Plan EIR
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449,489 ADT would be generated within the City's corporate limits and 186,416 would be
generated in the City Sphere-of-Influence (Sphere).
Within the City's corporate limits, the proposed Land Use Plan will generate about 3.6% more
traffic than build out of the 2002 General Plan. Within the City's Sphere, the proposed Land Use
Plan will generate about 34% more traffic than build out of the 2002 General Plan land use
designations in the Sphere. The following discussion and tables detail the impacts associated
with implementation and build out of the Preferred Alternative land use plan.
Roadway Segment Impact Analysis
As noted, for traffic analysis purposes General Plan build out is projected for the Year 2035. The
following Table III-48 identifies each roadways segment, projected 2035 ADT volumes, the
roadway designation/classification, the number of through lanes required based on the roadway
classification, future roadway capacity and volume to capacity ratios and level of service
projected in 2035.
Table III-48
General Plan Build Out (2035) Roadway Segment Analysis
(Peak Season)
Roadway Link 2035
ADT
Roadway
Designation
2035
Number
of
Lanes
2035
Capacity
2035
V/C Ratio
- LOS
Washington St
Ave 42 to Fred Waring Dr 58,241 Major 6 61,100 0.95 – E
Fred Waring Dr to Miles Ave 64,210 Major 6 61,100 1.05 – F
Miles Ave to Hwy 111 54,141 Major 6 61,100 0.89 – D
Hwy 111 to Ave 48 57,955 Major 6 61,100 0.95 – E
Ave 48 to Eisenhower Dr 58,267 Major 6 61,100 0.95 – E
Eisenhower Dr to Ave 50 41,381 Major 6 61,100 0.68 – B
Ave 50 to Calle Tampico 36,164 Major 6 61,100 0.59 – A
Eisenhower Dr
Washington St to Ave 50 21,435 Primary 4 42,600 0.50 – A
Avenue 50 to Calle Tampico 15,291 Primary 4 42,600 0.36 – A
Avenida Bermudas
Calle Tampico to Ave 52 3,919 Secondary 4 28,000 0.14 – A
Ave 52 to Calle Durango 10,836 Secondary 4 28,000 0.39 – A
Adams St
Westward Ho Dr to Hwy 111 21,347 Secondary 4 42,600 0.50 – A
Hwy 111 to Ave 48 22,132 Secondary 4 42,600 0.52 – A
Dune Palms Rd
Westward Ho Dr to Hwy 111 16,547 Secondary 4 28,000 0.59 – A
Hwy 111 to Ave 48 20,999 Secondary 4 28,000 0.75 – C
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Table III-48
General Plan Build Out (2035) Roadway Segment Analysis
(Peak Season)
Roadway Link 2035
ADT
Roadway
Designation
2035
Number
of
Lanes
2035
Capacity
2035
V/C Ratio
- LOS
Jefferson St
Country Club Rd to Fred Waring Dr 34,274 Major 6 61,100 0.56 – A
Fred Waring Dr to Miles Ave 44,436 Major 6 61,100 0.73 – C
Westward Ho Dr to Hwy 111 48,090 Major 6 61,100 0.79 – C
Hwy 111 to Ave 48 46,656 Major 6 61,100 0.76 – C
Ave 48 to Ave 50 53,649 Major 6 61,100 0.88 – D
Ave 50 to Ave 52 35,143 Major 6 61,100 0.58 – A
Ave 52 to Ave 54 31,532 Major 6 61,100 0.52 – A
Madison St
Ave 50 to Ave 52 34,204 Primary 4 42,600 0.80 – C
Ave 54 to Airport Blvd 47,529 Primary 4 42,600 1.12 – F
Airport Blvd to Ave 58 35,638 Primary 4 42,600 0.84 – D
Ave 58 to Ave 60 26,920 Secondary 4 42,600 0.63 – B
Monroe St
Ave 52 to Ave 54 32,749 Primary 4 42,600 0.77 – C
Ave 54 to Airport Blvd 34,453 Primary 4 42,600 0.81 – D
Jackson St
Ave 54 to Airport Blvd 28,524 Primary 4 42,600 0.67 – B
Airport Blvd to Ave 58 28,380 Primary 4 42,600 0.67 – B
Ave 58 to Ave 60 23,174 Primary 4 42,600 0.54 – A
Ave 60 to Ave 62 16,826 Primary 4 42,600 0.39 – A
Van Buren St
Ave 52 to Ave 54 28,531 Primary 4 42,600 0.67 – B
Ave 54 to Airport Blvd 22,172 Primary 4 42,600 0.52 – A
Airport Blvd to Ave 58 21,641 Primary 4 42,600 0.51 – A
Ave 58 to Ave 60 20,134 Primary 4 42,600 0.47 – A
Ave 60 to Ave 62 11,627 Secondary 4 28,000 0.42 – A
Harrison St
Airport Blvd to Ave 58 79,828
Augmented
Major 8 76,000 1.05 – F
Fred Waring Dr (Ave 44)
Washington St to Adams St 52,881 Primary 6 61,100 0.87 – D
Miles Ave
Washington St to Adams St 15,151 Primary 4 42,600 0.36 – A
Hwy 111
Washington St to Adams St 53,511 Major 6 61,100 0.88 - D
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Table III-48
General Plan Build Out (2035) Roadway Segment Analysis
(Peak Season)
Roadway Link 2035
ADT
Roadway
Designation
2035
Number
of
Lanes
2035
Capacity
2035
V/C Ratio
- LOS
Adams St to Dune Palms Rd 40,481 Major 6 61,100 0.66 – B
Dune Palms Rd to Jefferson St 50,659 Major 6 61,100 0.83 – D
Ave 48
Washington St to Adams St 16,902 Primary 4 42,600 0.40 – A
Dune Palms Rd to Jefferson St 32,855 Primary 4 42,600 0.77 – C
Ave 50
Washington St to Jefferson St 16,121 Primary 4 42,600 0.38 – A
Jefferson St to Madison St 30,593 Primary 4 42,600 0.72 – C
Calle Tampico
Eisenhower Dr to Avenida Bermudas 5,350 Primary 4 42,600 0.13 – A
Avenida Bermudas to Washington St 10,063 Primary 4 42,600 0.24 – A
Ave 52
Avenida Bermudas to Washington St 16,133 Primary 4 42,600 0.38 – A
Washington St to Jefferson St 31,770 Primary 4 42,600 0.75 – C
Jefferson St to Madison St 28,944 Primary 4 42,600 0.68 – B
Madison St to Monroe St 26,510 Primary 4 42,600 0.62 – B
Ave 54
Jefferson St to Madison St 29,390 Primary 4 42,600 0.69 – C
Airport Blvd
Madison St to Monroe St 17,177 Primary 4 42,600 0.40 – A
Ave 58
Madison St to Monroe St 10,199 Secondary 4 28,000 0.36 – A
Monroe St to Jackson St 18,633 Secondary 2 28,000 0.67 – B
Ave 60
Madison St to Monroe St 14,846 Secondary 4 28,000 0.53 – A
Monroe St to Jackson St 9,960 Primary 4 42,600 0.23 – A
Ave 62
Madison St to Monroe St 9,624
Modified
Collector 4 28,000 0.34 – A
Monroe St to Jackson St 19,822 Secondary 4 28,000 0.71 – C
Jackson St to Van Buren St 7,022 Secondary 4 28,000 0.25 – A
Van Buren St to Harrison St 3,631 Secondary 4 28,000 0.13 – A
Table III-48, above, indicates that the majority of the roadway segments are forecast to operate
at acceptable levels of service (V/C ratios less than or equal to 0.90 or LOS D or better), the six
roadway segments identified below are forecast to operate at an unacceptable LOS (V/C greater
than 0.90) based on assigned roadway classifications. Three segments are projected to operate at
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III-225
LOS E and three at LOS F at 2035 build out.
Washington Street segments between Avenue 42 and Miles Avenue and between Highway
111 and Eisenhower Drive (6-lane Major Arterial) are forecast to exceed theoretical
maximum carrying capacity by up to 3,000 VPD with the most problematic segment between
Fred Waring Drive and Miles Avenue. LOS D service volumes are exceeded by over 9,000
VPD.
Madison Street between Avenue 54 and Airport Boulevard (4-lane Primary Arterial) is
forecast to exceed theoretical maximum carrying capacity by approximately 4,900 VPD.
LOS D service volumes are exceeded by over 9,000 VPD.
Harrison Street between Airport Boulevard and Avenue 58 (8-lane Augmented Major) is
forecast to exceed theoretical maximum carrying capacity by approximately 3,800 VPD.
Although the capacity of Harrison Street was assumed to be that of an Augmented Major
Road (76,000 vehicles per day), it would likely operate as an Expressway due to limited
accessibility compared to an Augmented Major Road, thus carrying a larger capacity. Prior
study by the County raised the potential of grade-separated intersections to further enhance
capacity.
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Exhibit III-20
General Plan Build Out (2035) Average Daily Traffic Volumes
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Intersection Impact Analysis
A level of service analysis was conducted to evaluate forecast year 2035 operating conditions
with implementation of the Preferred Land Use Plan intersection operations during the a.m. and
p.m. peak hours. The projected levels of service reflect additional improvements (such as
signalization of stop-controlled intersections and intersection widening), which were deemed
feasible and are described in detail in the mitigation section of this discussion. Table III-49,
below, sets forth 2035 operating conditions assuming all required improvements are provided.
Table III-49
General Plan Build out (2035) Intersection Analysis
(Peak Season)
Intersection Traffic
Control
AM Peak Hour PM Peak Hour
LOS Delay
(Sec) LOS Delay
(Sec)
1. Washington St & Fred Waring Dr Signal D 37.3 D 54.2
2. Washington St & Miles Ave Signal C 25.5 D 40.8
3. Washington St & Channel Dr Signal B 13.1 C 24.3
4. Washington St & Hwy 111 Signal D 41.5 D 52.5
5. Washington St & Ave 48 Signal D 38.9 D 46.9
6. Washington St & Eisenhower Dr1 Signal C 28.3 C 31.4
7. Washington St & Ave 50 Signal C 23.3 C 33.8
8. Washington St & Calle Tampico2 Signal C 20.4 C 24.2
9. Washington St & Ave 52 Signal C 31.8 C 25.3
10. Eisenhower Dr & Calle
Tampico Signal C 23.1 C 24.6
11. Avenida Bermudas & Ave 52 Signal C 27.2 C 26.5
12. Adams St & Fred Waring Dr Signal C 31.9 D 37.0
13. Adams St & Miles Ave Signal C 34.7 D 46.6
14. Adams St & Hwy 111 Signal C 32.8 D 35.8
15. Adams St & Ave 48 Signal D 38.6 D 54.0
16. Dune Palms Rd & Fred Waring
Dr Signal B 19.3 C 30.3
17. Dune Palms Rd & Miles Ave Signal D 36.3 D 50.8
18. Dune Palms Rd & Westward Ho
Dr Signal C 32.5 D 43.5
19. Dune Palms Rd & Hwy 111 Signal C 32.4 D 41.1
20. Dune Palms Rd & Ave 48 Signal C 25.3 C 31.2
21. Jefferson St & Fred Waring Dr Signal D 36.9 D 44.9
22. Jefferson St & Hwy 111 Signal C 32.1 D 53.8
23. Jefferson St & Ave 48 Signal D 40.4 D 46.2
24. Jefferson St & Ave 49 Signal B 17.7 B 16.9
25. Jefferson St & Ave 50 Signal C 33.9 D 43.4
26. Jefferson St & Ave 52
Roundab
out A 3.0 A 3.4
27. Jefferson St & Ave 54
New
Signal3 B 15.3 B 15.4
28. Madison St & Ave 50
New
Signal3 D 38.2 D 51.4
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Table III-49
General Plan Build out (2035) Intersection Analysis
(Peak Season)
Intersection Traffic
Control
AM Peak Hour PM Peak Hour
LOS Delay
(Sec) LOS Delay
(Sec)
29. Madison St & Ave 52
New
Signal3 D 39.8 D 54.5
30. Madison St & Ave 54
New
Signal3 D 38.2 D 52.7
31. Madison St & Ave 58
New
Signal3 C 24.7 D 52.6
32. Madison St & Ave 60
New
Signal3 D 51.8 D 38.7
33. Monroe St & Ave 52
New
Signal3 C 33.9 D 53.7
34. Monroe St & Ave 54
New
Signal3 C 30.2 D 44.8
35. Monroe St & Ave 58
New
Signal3 C 34.9 D 46.6
36. Monroe St & Ave 60
New
Signal3 C 30.7 D 43.3
37. Monroe St & Ave 62
New
Signal3 B 10.3 B 13.5
Notes:
LOS = Level of Service, Delay = Average Vehicle Delay (Seconds), V/C = Volume‐‐to‐‐
Capacity Ratio.
1 = Calculation based on implementation of a second southbound right‐‐turn lane (per 2011
CIP).
2 = Calculation based on implementation of a third eastbound left‐‐turn lane (per 2011 CIP).
3 = 2035 Conditions assume signalization of existing lanes.
A thorough analysis has been made of the physical improvements that are required to assure that
all the major intersections operate at acceptable levels of service (LOS D or better) in 2035. Of
the 37 intersections analyzed, the following four are not expected to be able to accommodate all
the required build out improvements and therefore have the potential to be operating at
unacceptable levels of service by 2035 General Plan build out:
Washington Street @ Fred Waring Drive;
Adams Street @ Miles Avenue;
Jefferson Street @ Highway 111;
Madison Street @ Avenue 50.
It should also be noted that three of the four impacted intersections are shared between more than
one jurisdiction. For instance, the Washington Street/Fred Waring Drive intersection is located
within the corporate boundaries of the cities of La Quinta, Palm Desert and Indian Wells. In
these cases, close and on-going coordination between cities will be necessary provide optimum
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intersection improvements and to otherwise address forecast operational deficiencies.
All-Weather Access
The City's roadway network and the neighborhoods it serves are generally well protected from
isolation due to flooding. Multiple points of access across the Whitewater River and the La
Quinta Evacuation Channel and additional all-weather facilities are planned in conjunction with
future development, which will preclude their isolation from flood events. Therefore, the
implementation of the proposed general Plan will not have a significant adverse impact on limits
of accessibility, including limits associated with flooding.
Public Transportation
Implementation of the proposed General Plan is expected to have a less than significant impact
on public transit facilities in the Valley. The major corridors where bus service is currently
provided are expected to continue to serve the areas of major demand for such services. The
General Plan Circulation Element provides policies and programs that will facilitate continued
coordination between the City and SunLine Transit to assure that the levels of transit service are
maintained and, where necessary, expanded.
Air Transportation
The continuing build out of the La Quinta planning area and the Coachella Valley in general will
contribute to increased demand for air transport services, particularly passenger service. In
addition to substantial capacity at the Palm Springs International Airport, current and planned
development at the Jacqueline Cochran Regional Airport will increase services at this airport.
Implementation of the proposed General Plan is expected to have a less than significant impact
on air transportation facilities in the Valley.
Railway Facilities
Union Pacific Railroad has recently expanded their rail facilities passing through the Valley and
there are substantial rail siding and associated facilities adjacent to UPRR lines that are expected
to meet future demand for several decades to come. Therefore, Implementation of the proposed
General Plan is expected to have a less than significant impact on public transit facilities in the
Valley.
3. Mitigation Measures
Mitigation Overview
The General Plan Circulation Element and the associated Traffic Impact Analysis identify and
address potential roadway network inadequacies that could result in unacceptable levels of
service. Areas of mitigation include roadway segment (mid-block) design, intersection design, as
well as a wide range of system improvements, management strategies, and the implementation of
a "Complete Streets" program, as set forth in the Circulation Element. How these mitigation
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measures and strategies are applied to the City's roadway network and the efficacy are discussed
below.
General Mitigation Measures and Strategies
In addition to standard mitigation involving physical street and intersection widening, a variety
of largely non-physical improvements will be applied and include the development and
implementation of transportation systems management and transportation demand management
(TSM and TDM) strategies. Also available are Intelligent Transportation System strategies,
which are primarily technologic add-on that can significantly enhance the operation of the City's
transportation system. Each of these mitigation programs is described below and will be applied
throughout the City
Transportation Demand Management
To the greatest extent practicable, the City will implement TDM strategies in both land use and
transportation planning. TDM programs are designed to put more person trips into fewer
vehicles, by increasing vehicle occupancy or car-pooling, vanpools, and transit ridership. TDM is
also integral to integrated land management consistent with SB 375 and also includes planning
efforts that increase the use of bicycling, golf carts and neighborhood electric vehicles (NEVs),
as well as increased pedestrian modes of travel. The effectiveness of TDM strategies depends on
their levels of application.
Transportation Systems Management
To the greatest extent practicable, the City will implement TSM strategies in transportation
planning. TSM programs and projects are designed to support travelers with real time travel
information so that they can make smart travel choices in selection of time, mode and routes of
travel. TSM projects can also offer Intelligent Transportation Systems (ITS) projects for the most
efficient traffic signal coordination and for informing motorists of routes around traffic
congestion that may result from special events and traffic incidents. TSM programs are very
effective when integrated into planned major events, such as scheduled music and art festivals,
golf or tennis matches, and other special events that generate significant amounts of event traffic.
Roadway Segment Impact Mitigation
As noted in the impacts discussion, six roadway segments have been identified where the City
may not be able to implement all the required physical improvements needed to assure LOS D or
better operation in 2035. As noted in the Circulation Element and the General Plan Traffic
Impact Analysis, getting all roadway segments to operate at LOS D or better in 2035 will require
ongoing focus on well coordinated operations of traffic signals and access control along the
segments to maximize efficient circulation. Roadway segment theoretical maximum carrying
capacities, also called “service volumes,” can be increased with delivery of more uniform travel
speeds and less slowing and stopping at red lights.
The following mitigation strategies are recommended to further improve operating conditions
along these segments.
Ongoing and diligent focus on well-coordinated operations of traffic signals will help maximize
efficient circulation along these segments. Maximum roadway carrying capacities (or “service
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III-231
volumes”) can be increased with more uniform travel speeds and less slowing and stopping at
red lights. This is best accomplished with implementation of an Intelligent Transportation
Systems master plan. The following recommendation should be implemented to increase
roadway capacity without the addition of travel lanes along segments operating unacceptably:
1. Commit to ongoing funding and operations of intelligent transportation systems
management, as described above, to:
a. Deliver traffic signal coordination along corridors in “real time” to optimize the
progression of vehicles at the most efficient travel speeds;
b. Operate Transit Signal Priority at signals along major transit routes to optimize traffic
flow;
c. Operate Dynamic Message Signs to route traffic around congestion/to available parking
during peak periods and planned events.
2. Continue with the City’s established minimum driveway spacing and access restrictions;
3. Construct median islands with minimum opening spacing; and/or;
4. Add bus turnouts at bus stops along major transit routes.
The following segment-specific recommendations will further enhance operating efficiencies
along these segments.
Washington Street Roadway Segment Deficiencies: The application of Transportation Demand
Management (TDM) and Transportation Systems Management (TSM) strategies will effectively
reduce peak hour traffic volumes along this segment, but it may still operate at unacceptable
levels of service (LOS E or F) during peak hour upon General Plan build out. Therefore,
potential impacts may not be fully mitigated below levels of significance.
Madison Street Roadway Segment Deficiency: The General Plan traffic analysis identified a
segment deficiency on Madison Street between Airport Boulevard (Ave 56) and Avenue 54.
There is some question whether this level of impacts will actually occur. Nonetheless, mitigation
measures include the application of TDM and TSM strategies to reduce peak hour traffic
volumes along this segment. It may still operate at unacceptable levels of service (LOS E or F)
during peak hour upon General Plan build out. Therefore, potential impacts may not be fully
mitigated below levels of significance.
Harrison Street Roadway Segment Deficiency: As an 8-lane Augmented Major Arterial,
Harrison Street between Airport Boulevard (Ave 56) and Avenue 58 is forecast to exceed
theoretical maximum carrying capacity by approximately 3,800 VPD. Harrison Street is assumed
to function as an Augmented Major Road (76,000 vehicles per day), and would likely operate as
an Expressway due to limited accessibility. Application of TDM and TSM strategies will help
reduce peak hour traffic volumes along this segment but it may still operate at unacceptable
levels of service (LOS E or F) during peak hour upon General Plan build out. Therefore,
potential impacts may not be fully mitigated below levels of significance.
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Intersection Impact Mitigation
As discussed above, intersections constitute the most constrained portion of the roadway network
in the City the planning area. The following exhibit identifies the 37 intersections analyzed and
illustrates the improvements (mitigation measures), both those already programmed and
new/additional improvements, needed to provide acceptable levels of service (LOS D).
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Special Intersection Management Provisions
As noted in the General Plan Traffic Impact Analysis (TIA) and this Circulation Element, it may
not be possible to implement all of the recommended intersection improvements. These
constrained intersections have been identified above, and recommendations for further enhancing
the operation of these intersections and further mitigating adverse impacts by other means is
described below.
The intersection improvements necessary to provide acceptable LOS upon build out of the
preferred General Plan were detailed above. Some of the potential improvements would affect
and require the cooperation of neighboring cities. In some instances, needed improvements could
affect existing buildings and other structures, and may not be feasible. In addition, some
recommendations from the Washington Street/Highway 111 Transportation Systems
Management (TSM)/Transportation Demand Management (TDM) Corridor Study (VRPA,
September 2009) are also considered. Special considerations for constrained intersections are as
follows:
Washington Street @ Fred Waring Drive: Two approaches to achieving acceptable intersection
operations may be combinations of 1) street widening, and 2) TSM/TDM measures. The
application of TSM/TDM will depend on the extent of widening that is determined to be feasible,
as presented below:
a. Intersection Widening
1. City of La Quinta jurisdiction widening could add a third northbound left-turn lane and a
fourth northbound through lane. This would improve AM peak hour conditions to LOS E.
The PM peak hour conditions would remain at LOS F but the average intersection delay
would be reduced by 38 seconds per signal cycle.
2. Coordinate with the City of Palm Desert to consider the potential for improvements in the
northwest intersection quadrant, specifically the adding of a fourth southbound through
lane, a fourth westbound through lane, and a westbound right-turn overlap phase. With
construction of these added to the widening recommended in the City of La Quinta, PM
peak hour conditions would remain at LOS F but the average intersection delay would be
reduced by an additional 20 seconds.
The City of Palm Desert General Plan (2004) does not call for these improvements, but
does call for consideration of a third northbound left-turn lane in the City of Indian Wells,
which is consistent with improvements in the City of La Quinta identified above. The
City of Palm Desert should be encouraged to continue to coordinate with the City of
Indian Wells for construction of an eastbound free-right turn lane.
3. Coordinate with the City of Indian Wells to consider improvements in the southwest
intersection quadrant, specifically the adding of a fourth eastbound through lane and a
second eastbound right-turn lane with a right-turn overlap phase. With construction of the
two City of Indian Wells improvement-impacting lanes, but not assuming improvements
in the City of Palm Desert, PM peak hour conditions would remain at LOS F but the
average intersection delay would be reduced by an additional 26 seconds.
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4. If the recommended improvements in the Cities of La Quinta, Palm Desert, and Indian
Wells are all implemented, the PM peak hour conditions would be improved to LOS D
operations.
5. Implement TSM/TDM measures for trip rerouting, in addition to some of the above listed
improvements that are determined feasible.
a. Design and implement an Intelligent Transportation Systems (ITS) Master Plan in
coordination with the cities of Palm Desert and Indian Wells, and in coordination
with the Indian Wells Tennis Event Center. An ITS Plan would enable dynamic route
reassignment of traffic around congestion and direct traffic to available parking
through the use of Dynamic Message Signs and adaptive traffic signal control. The
Plan would deliver the best access to events for attendees, and around event traffic for
residents that are not attending the events.
To achieve non-event LOS E operations, and to minimize the level of impacts
experienced at nearby intersections, approximately 200 northbound left-turning
vehicles would need to be diverted, approximately 100 southbound left-turning
vehicles would need to be diverted, and approximately 100 southbound through
movement vehicles would need to be diverted. Assuming these trip diversions, the
necessary roadway widening improvements would be reduced to the addition of
the third northbound left-turn lane (City of La Quinta), the second eastbound
right-turn lane with a right-turn overlap phase (City of Indian Wells), and a fourth
westbound through lane (Cities of La Quinta and Palm Desert). Therefore, the 4th
northbound through lane, 4th southbound through lane, 4th eastbound through lane,
and westbound right-turn overlap phase, recommended previously, would no
longer be necessary.
In order to achieve non-event LOS D operations, assuming the same approximate
ranges of trip diversion shown above, the addition of the fourth eastbound through
lane, the westbound right-turn overlap phase, and third eastbound left-turn lane
would be required. Therefore, the 4th northbound through lane and 4th southbound
through lane, recommended previously, would continue to no longer be
necessary.
Adams Street @ Miles Avenue: Add a dedicated westbound right-turn lane, converting the
number two through lane to a through only lane. Implementation of this improvement alone will
achieve LOS E operations in the PM peak hour. Consider adding a dedicated northbound right-
turn lane, converting the number two through lane to a through only lane order to achieve LOS D
operations. This could impact three to four residential property yards and require relocation of
power poles. This measure may not be feasible.
Jefferson Street @ Highway 111: Coordinate with the City of Indio in optimizing future
intersection improvements. To the extent practicable, add a fourth northbound through lane. Add
a fourth southbound through lane. Add a third southbound left-turn lane. While the prescribed
third southbound left-turn lane may be feasible, the fourth north and southbound through lanes
do not appear to be. Intersection operations will benefit from TSM programs and overall TDM
efforts.
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Madison Street @ Avenue 50: – Add a third northbound through lane and a dedicated right-turn
lane, converting the new number three through lane to a through only lane. Add a dedicated
southbound right-turn lane, converting the new number two through lanes to a through only lane.
Add a westbound dedicated right-turn lane with a right-turn overlap phase, converting the new
number two through lane to a through only lane. Add a second eastbound through lane and a
dedicated eastbound right turn lane. Management prescriptions include coordinating with the
City of Indio to signalize this intersection. It should be noted that the City of Indio plans to
maintain the planned four-lane roadway segment on Madison Street between Avenue 50 and 48.
Therefore, further analysis and the application of TDM and TSM strategies are warranted.
Madison Street @ Avenue 52: - Although not required by the traffic analysis, add a second
northbound left turn lane to help transfer future northbound traffic to the west and reduce
otherwise anticipated volumes on the northbound leg at the intersection of Madison Street and
Avenue 50.
In summary, while a variety of improvements and management strategies are prescribed for these
four intersections, not all improvements may be possible and these intersections could operate at
LOS E or F during peak periods by 2035.
Mitigation via Implementation of General Plan Policies and Programs
The Circulation Element of the Comprehensive General Plan includes twenty-six (26) policies
and twenty-nine (48) programs, which are designed to enhance the operation and efficiency of all
aspects of the transportation system serving the planning area. Policies and programs address the
on-going monitoring and management of traffic volumes and operating conditions, and the
timing of required improvements to maintain acceptable levels of service.
Summary of Mitigation
The General Plan, this EIR and the General Plan Traffic Study provide both programmatic and
concrete/prescriptive actions and measures that are expected to reduce transportation impacts
associated with the implementation of the proposed General Plan. In conjunction with the
existing various regional transportation initiatives coordinated through the City and CVAG, the
performance of transportation systems serving the City and planning area can be further
enhanced. The continued thoughtful integration of land uses will also increase opportunities for
mass transit and non-motorized means of transportation. Controlling access onto major arterial
roadways will also serve to preserve capacity and limit the costs associated with expanded
roadway infrastructure.
Even with the substantial feasible improvements and the implementation of TDM and TSM
programs and strategies, up to six roadway segments and four intersections may operate at LOS
E or F in build out year 2035.
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Mitigation Monitoring/Reporting Program
A. The City shall review and update the master plan of roads, including standards for ultimate
rights-of-way and pavement width, and update Capital Improvement Programs (CIP) to
ensure the timely securing of rights-of-way and construction of improvements consistent
with the projected needs and standards set forth in the Circulation Element and Program
EIR.
Responsible Parties: City Council, Planning Department, Public Works Department
B. The City shall establish and maintain ongoing consultation and coordination with planning
and engineering staffs of adjoining cities and transportation planning agencies to study and
implement effective means of preserving and improving capacity along major roadways.
Coordination efforts may include synchronized signalization, consolidation of access drives
and restriction of access, construction of additional travel and turning lanes, raised median
islands, and improvements to critical intersections.
Responsible Parties: Public Works Department, Planning Department, Adjoining Cities,
CVAG, Riverside County, Caltrans
C. The City shall periodically evaluate the operating conditions at each of the constrained
intersections, and shall make recommendations to responsible agencies regarding needed
improvements.
Responsible Parties: Public Works Department, Planning Department, Caltrans, Riverside
County, CVAG
D. The City shall pro-actively consult and coordinate with CVAG, SCAG and Caltrans and
represent the City in transportation planning meetings to assure that City policies, programs
and strategies are given full consideration in resolving regional transportation issues
affecting the community.
Responsible Parties: City Council, Planning Department, Public Works Department,
CVAG, SCAG, Caltrans
E. The City shall continue to pro-actively promote the mass transit system expansion and
innovation through ongoing consultation and coordination with the SunLine Transit
Agency and CVAG.
Responsible Parties: City Council, Planning Department, Public Works Department,
SunLine Transit Agency, CVAG
F. The City shall continue to consult and coordinate with the SunLine Transit Agency and
encourage the development of rideshare and other alternative, high occupancy transit
programs for employers with sufficient numbers of employees, and for individuals seeking
to locate potential rideshare partners.
Responsible Parties: City Council, Planning Department, SunLine Transit Agency
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G. The City shall monitor the effectiveness of land use planning proposals that integrate a mix
of land uses, optimizes nearby interactions, reduce the need for travel outside the
neighborhood, and shorten trips to work, shopping, public services and public park
facilities.
Responsible Parties: Planning Department, Redevelopment Agency
H. The City shall monitor the effectiveness of its master plan of bicycle-ways, golf cart/NEV
routes and multi-use paths, including secure bicycle and golf cart/NEV storage facilities,
and other support facilities which increase bicycle and golf cart use.
Responsible Parties: Planning Department, Public Works Department
I. The City shall periodically review roadway design specifications, design standards and
guidelines for public and private streets, and their effectiveness at meeting existing and
anticipated demand, reducing traffic speeds in neighborhoods, and facilitating safe and
efficient use of bicycles and other alternative modes of transportation.
Responsible Parties: Planning Department, Public Works Department, Planning
Commission, City Council
Water Resources & Quality P.
Introduction
The existing water supply and water quality conditions for the General Plan Planning Area are
discussed in this section. This section describes existing and future water demand to determine
potential impacts on water supplies and water quality from the implementation of the proposed
General Plan. Also considered is the current and projected availability and reliability of water
supplies, including those associated with imported Colorado River and State Water Project
water, as well from other water sources that have been identified.
The Coachella Valley Water District (CVWD) is responsible for managing water resources in the
region, including the General Plan area. CVWD delivers domestic and irrigation water to La
Quinta and its Sphere. Therefore, this section also discusses CVWD’s ability to provide water
supplies over the course of General Plan build out.
The Coachella Valley Urban Water Management Plan (CVWD UWMP), the CVWD Draft
Water Management Plan and other CVWD reports, as well as materials from the California
Department of Water Resources and other entities, have been consulted in the preparation of this
discussion.
Thresholds of Significance/Criteria For Determining Significance
The following standards and criteria have been drawn from Appendix G: Environmental
Checklist Form of the CEQA Guidelines. The following factors have been considered to ensure
that the General Plan EIR adequately addresses potential impacts to water resources that may
result from the adoption and implementation development of the General Plan. Implementation
of the La Quinta General Plan will have a significant impact on water resources and quality if it
would:
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a.) Violate any water quality standards or waste discharge requirements.
b.) Substantially deplete groundwater supplies or interfere substantially with groundwater
recharge such that there would be a net deficit in aquifer volume or a lowering of the
local groundwater table level (e.g., the production rate of pre-existing nearby wells would
drop to a level which would not support existing land uses or planned uses for which
permits have been granted).
c.) Substantially alter the existing drainage pattern of the site or area, including through the
alteration of the course of a stream or river, in a manner that would result in substantial
erosion or siltation on- or off-site.
d.) Substantially alter the existing drainage pattern of the site or area, including through the
alteration of the course of a stream or river, or substantially increase the rate or amount of
surface runoff in a manner that would result in flooding on- or off-site.
e.) Create or contribute runoff water that would exceed the capacity of existing or planned
stormwater drainage systems or provide substantial additional sources of polluted runoff.
f.) Otherwise substantially degrade water quality.
It should be noted that items c through e above are addressed Section H: Hydrology of this EIR.
1. Existing Conditions
The Coachella Valley and the Planning Area are within the Colorado River Watershed, which
drains into the Salton Trough. The desert climate is characteristically dry, with an average of less
than 4 inches of annual rainfall. Therefore, water is an especially limited and valuable resource.
To satisfy the demand for water from residential, commercial and agricultural users, the
Coachella Valley supplements local groundwater supplies with water from Northern California
and the Colorado River.
Northern California water is conveyed to Southern California via the California aqueduct. Over
23 million people and 755,000 acres of agricultural lands are served.106 Supplies to southern
California vary annually based on weather. Water supplies are more available in wet years and
decrease during dry years.
California is entitled to 4.4 million acre feet of Colorado River water per year, as set forth in a
1964 Supreme Court ruling. Although Colorado River water is one of the Coachella Valley’s
main sources of water, it has elevated levels of salinity. This water has been cited as contributing
to the elevated salinity levels found in the Valley. These issues are further discussed below under
Water Quality.
106 Department of Water Resources and Public Affairs, www.publicaffairs.water.ca.gov/swp/.
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Whitewater River Subbasin107
The Coachella Valley is underlain by a substantial subsurface groundwater basin. Over millions
of years, conditions created by the Valley’s geology and water runoff from surrounding
mountains have resulted in water collecting in the aquifer, which generally extends from the
Whitewater River in the northwest to the Salton Sea in the southeast. The aquifer is naturally
divided by fault barriers into subbasins, which are further divided into subareas. The Whitewater
River Subbasin (also known as the “Indio Subbasin”) encompasses approximately 400 square
miles and underlies most of the Coachella Valley. It is bounded on the north by Garnet Hill
Fault, on the east by the San Andreas Fault, and on the south by the San Jacinto and Santa Rosa
Mountains. It is estimated that the Subbasin contains approximately 28.9 acre-feet of
groundwater within the first 1,000 feet below the ground surface.
There are five subareas within the Whitewater River Subbasin: the Palm Springs subarea, the
Garnet Hill subarea, the Thermal subarea, the Thousand Palms subarea, and the Oasis subarea.
The City and Sphere are underlain by the Thermal subarea, which is part of the Lower
Whitewater River Subbasin.
Thermal Subarea
The division between the upper and lower portions of the Whitewater River subbasin is located
in the Thermal subarea. The juncture of the Thermal Subarea with the Palm Springs Subarea,
which lies to the west, occurs near Cathedral City. Based on measurement data for the Palm
Springs and Thermal subareas, there appears to be no distinction between the water tables of the
upper and lower subarea, except for the “hinge effect” of the Thermal subarea at Point Happy.
Groundwater levels have generally remained stable, although more recently, increased pumpage
has lowered groundwater levels in the lower portion of the Whitewater River subbasin.
Conditions in most of the Thermal Subarea are confined or semi-confined, with movement
caused by differences in piezometric (pressure) levels. Although unconfined or free water
conditions occur within alluvial fans such as those that at the base of the Santa Rosa Mountains,
an area of reduced permeability, or “aquitard” occurs between the two aquifers. Reduced
permeability is created where fine grained materials such as sand and gravel lenses occur. This
aquitard forms the boundary between the upper and lower aquifers in the Thermal subarea.
The upper and lower aquifer zones of the Thermal subarea have similar lithology108, although the
lower aquifer is thought to be thicker and to receive more subsurface inflow than the upper
aquifer. The lower aquifer is considered the most important source of groundwater in the
Coachella Valley Groundwater basin. It serves the area easterly of Washington Street, which
includes the La Quinta Planning Area. In this portion of the subarea, the top of the water table
ranges from 300 to 600 feet below the surface. Although undetermined, the aquifer is believed to
be at least 500 feet thick and some estimates suggest that it may be over 1000 feet thick. While
the aquifer contains vast water supplies, water table levels vary based on demand. Underlying the
107 “Engineer’s Report on Water Supply and Replenishment Assessment: Lower Whitewater River Subbasin Area
of Benefit, 2011-2012,” prepared by Coachella Valley Water District, May 2011. 108 A rock or rock formation’s gross physical character.
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lower subarea is an aquitard that is generally 100 to 200 feet thick, and up to as much as 500 feet
thick in some areas along the edge of the Salton Sea.
Regional Water Supply and Demand
The Coachella Valley’s principal domestic water source is groundwater. The subbasins
underlying the Coachella Valley contain approximately 39.2 million acre-feet of water, of which
about 28.8 million are within the Whitewater River subbasin. Natural recharge from precipitation
and mountain runoff, supplemented with artificial recharge from imported Colorado River and
State Water Project water, and recycled water from wastewater treatment plants also provide
water to the Coachella Valley.
During the twentieth century the Coachella Valley experienced a rapid depletion of its
groundwater in storage. CVWD data shows that significant increases in total water demand in
the Coachella Water Valley occurred during over the decades from 1936 (92,400 acre feet/year
(AFY) to 376,000 AFY in 1999. The increase in water demand reflects both municipal water and
agricultural irrigation. This is consistent with the growth of two primary economic activities in
the Coachella Valley: agriculture and tourism. Agriculture began to develop as a viable industry
in the Coachella Valley in the early 1900’s, especially in the eastern Valley. More recently, the
region has emerged as a leading destination resort area, characterized by lushly landscaped golf
courses and residential communities. In 2009 groundwater use decreased to approximately
358,700 AFY, through the implementation of conservation measures, source substitution projects
and the impacts of the economic downturn.
Regional Water Supply
Domestic water is provided in the City and most of the Sphere by CVWD. Groundwater is the
primary source for this water supply, which CVWD extracts from the Whitewater River
Subbasin by means of a system of deep wells within the region.
Total outflows exceed inflows in the Lower Whitewater River Subbasin Area of Benefit,
resulting in a condition known as overdraft. This condition has resulted in a decline in
groundwater levels in many portions of the eastern Valley from La Quinta to the Salton Sea.
Concerns related to these conditions include potential degradation of water quality and land
subsidence. Water quality concerns are addressed herein; for further discussion of land
subsidence, please see Section III-F, Geology and Soils.
CVWD estimates the annual overdraft balance based on outflows and inflows. It considers
outflows due to production, subsurface drainage, including the agricultural tile drain system, and
evapotranspiration from vegetation. Sources of inflow include natural inflow, non-consumptive
return from groundwater and imported water use, and groundwater replenishment efforts. Based
on these factors, the annual balance in the Area of Benefit through 2010 was estimated to be -
7,457 acre-feet. The cumulative overdraft for the Area of Benefit through 2010 is estimated to be
4,497,609 acre-feet.109
109 Table 3, “Engineer’s Report on Water Supply and Replenishment Assessment: Lower Whitewater River
Subbasin Area of Benefit, 2011-2012,” prepared by Coachella Valley Water District, May 2011.
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Historic and Current Consumption
As shown in Table III-50, below, water withdrawals, or groundwater production, in the Lower
Whitewater Subbasin Area of Benefit have remained generally stable since 1999.
Table III-50
Coachella Valley Water District Annual Water
Production Within the Lower Whitewater River
Subbasin Area of Benefit
1999 – 2010
Year Acre-Feet Million Gallons
19991 168,300 54,866
20002 166,700 54,344
2001 199,800 65,135
2002 172,300 56,170
2003 170,000 55,420
2004 170,000 55,420
2005 170,000 55,420
2006 170,000 55,420
2007 170,000 55,420
2008 170,000 55,420
20093 160,000 52,160
2010 150,000 48,878
1From the “Coachella Valley Water Management Plan, Table 3-2,
Summary of Historical Water Supplies in 1936 and 1999” prepared
by Montgomery Watson Harza.
22002-2008 from the “Engineer’s Report on Water Supply and
Replenishment Assessment: Lower Whitewater River Subbasin Area
of Benefit, 2010-2011, Table 2” prepared by Coachella Valley Water
District, April 2010. 3Assessable groundwater production estimated from reported and
projected unreported groundwater production.
Source: “Engineer’s Report on Water Supply and Replenishment
Assessment: Lower Whitewater River Subbasin Area of Benefit,
2011-2012, Table 2” prepared by Coachella Valley Water District,
May 2011.
Domestic Water Facilities110,111
The CVWD domestic water system is comprised of a system of 30 pressure zones in which water
supplies are drawn from 102 active wells. CVWD uses pressure booster pump and regulating
valve stations to transfer water between pressures zones. 112 The Planning Area is served by the
110 http://www.cvwd.org/about/waterandcv.php 111 Written communication, Mark Johnson, Coachella Valley Water District, December 28, 2010. 112 “Coachella Valley Water District Development Design Manual,” prepared by Coachella Valley Water District,
2010.
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following pressure zones: Valley, Upper, Middle and Lower La Quinta, and Lake Cahuilla.113
The District has 59 storage reservoirs. Domestic water is distributed via a system of pipelines
ranging in size from 4-inches to 36-inches in diameter, located in public street rights of way. In
2011, CVWD delivered 102,805 acre-feet of water to a population of 286,240 in its service area.
Currently CVWD has 21 active wells in the General Plan Area. In addition, there are 6 booster
stations and 10 planned or existing reservoirs in the Planning Area. Each reservoir has between
250,000 and 12 million gallons of capacity, with a total storage capacity of all reservoirs of 44.6
million gallons.114 CVWD has no plans to construct additional reservoirs in La Quinta at this
time.
Imported Water
Imported State Water Project exchange water and Colorado River water provide additional water
resources to the Valley. These sources are further discussed below. CVWD utilizes imported
water to supply its recharge basins behind Dike 4 and its pilot facility in Martinez Canyon, as
well as in the western portion of the Coachella Valley.
Colorado River Water
Colorado River Water is one of Coachella Valley’s main sources of water. It is delivered via the
Coachella branch of the All-American Canal, which extends throughout the Valley and
terminates at Lake Cahuilla in southern La Quinta. Based on the Quantification Settlement
Agreement (QSA), which quantifies Colorado River water allocations to agricultural water
contractors and provides for water transfers between agencies, CVWD is entitled to 368,000
acre-feet per year in 2010. Total deliveries, once reduced by conveyance and distribution losses,
are 337,000 acre-feet per year.115 Future allocations will increase by year 2026 through the end
of the 75-year QSA term. The amount of Colorado River water that the Coachella Valley
actually receives each year varies based on the amount of precipitation that occurs in the
Colorado River watershed.
Issues affecting the long-term reliability of the Valley’s Colorado River supply include an
extended drought in the Colorado River Basin, the Colorado River shortage sharing agreement,
issues related to protection of endangered species and habitat, climate change and legal
challenges to the validity of the QSA. Although the state and CVWD have high priority status
for the allocations provided for under the QSA and these supplies are expected to be reasonably
reliable, state court decisions regarding lawsuits are pending until at least 2011.116
113 La Quinta Pressure Zones Map, prepared by Coachella Valley Water District, December 28, 2010. 114 “Technical Background Report to the Safety Element Update, City of La Quinta, CA” prepared by Earth
Consultants International, September 2010. 115 Table 4-2, “Draft Coachella Valley Water District Water Management Plan” prepared by Montgomery Watson
Harza, December 2010. 116 “Draft Coachella Valley Water District Water Management Plan” prepared by Montgomery Watson Harza,
December 2010.
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State Water Project
CVWD, along with Desert Water Agency (DWA), contracts with the Metropolitan Water
District (MWD) for access to State Water Project (SWP) water in the Coachella Valley. Since no
physical SWP water delivery facilities exist in the Valley, CVWD and DWA access SWP water
through an exchange of Colorado River water from MWD’s Colorado River Aqueduct, which
extends through the Coachella Valley.
In addition to the original “Table A” allocation contracts begun in 1962 and 1963, CVWD and
DWA have contracted for additional SWP water from MWD through agreements reached in
2003, 2004 and 2007. Currently, all CVWD SWP sources, including the original and subsequent
agreements, total 138,350 acre-feet per year. Based on the SWP Delivery Reliability Report
issued by DWR, the average reliability of SWP Table A allocations through 2029 is 60%, which
accounts for climate change. This represents a decrease in published reliability from previous
DRR estimates.117 Accounting for all factors affecting the overall reliability of SWP supplies,
CVWD assumes a long-term reliability of 50%.
CVWD uses SWP exchange water to recharge the Upper Whitewater River and the Mission
Creek Subbasin Areas of Benefit at recharge facilities located near Palm Springs.
Groundwater Recharge118
CVWD has implemented a groundwater replenishment program to prevent adverse impacts from
the depletion of groundwater reserves. As noted above, imported water supplies from the
Colorado River and State Water Project are used to artificially recharge the Upper and Lower
Whitewater River and Mission Creek Subbasin Areas of Benefit at CVWD recharge facilities in
the Valley. CVWD has operated the Whitewater River Spreading Facility near Palm Springs
since 1973, utilizing over 2 million acre-feet of SWP water. It has a recharge capacity of 300,000
acre-feet per year, and an annual recharge goal of 100,000 AFY.
The Thomas E. Levy Groundwater Replenishment Facility, located within the impoundment area
of Dike 4 in the southern portion of the La Quinta General Plan Area. The Levy facility was
operated as a pilot program beginning in 1997, with full-scale operations completed in 2009. It
has an average recharge capacity of 40,000 AFY, which is limited by hydraulic and water
delivery constraints associated with the Canal water distribution system. Therefore, the long-
term average capacity is estimated of 32,000 AFY. In future, an additional pipeline and pumping
station from Lake Cahuilla may be constructed.
CVWD has conducted a pilot recharge program at the second east Valley recharge facility in
Martinez Canyon, south of the Planning Area, since 2005. When full-scale operations come on-
line, the Martinez Canyon facility is expected to have an average annual recharge capacity of
between 20,000 and 40,000 AFY. CVWD estimates that this project will begin initial full-scale
operation in 2016, and reach capacity by 2018.
117 Table 4-4, “Draft Coachella Valley Water District Water Management Plan” prepared by Montgomery Watson
Harza, December 2010. 118 “Draft Coachella Valley Water District Water Management Plan” prepared by Montgomery Watson Harza,
December 2010.
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Additional Water Sources
Recycled Water/Tertiary Treated Water
Reclaimed or tertiary treated water can be used for landscape irrigation, thus reducing the
amount of domestic water required for such uses. There are six CVWD water reclamation plants,
of which two have facilities to treat wastewater to tertiary levels, which is non-potable but
suitable for irrigation. A third CVWD water reclamation plant produces secondary treated water
suitable for irrigation where uses are restricted. WRP-7, located in north Indio, serves the
Planning Area, and has capacity to tertiary treat 2.5 million gallons of wastewater daily, with
potential to expand up to 7.5 mgd. A second plant, WRP-4, located in Thermal, also serves the
Planning Area but does not currently recycle wastewater. CVWD plans for this use in future as
demand increases.119
CVWD is the regional stormwater agency and maintains regional drainage facilities in La
Quinta, including agricultural drainage facilities. A system of CVWD laterals connected to the
Coachella Canal currently deliver irrigation water to golf course and agricultural development in
La Quinta. As agricultural uses are converted to residential and other urban development,
particularly in the Sphere, these systems may continue to be used to deliver non-potable water to
irrigate landscaping associated with future development.120
Water Conservation
CVWD and the City of La Quinta implement a variety of water conservation efforts that are
responsive to local conditions and compliant with state legislative requirements. Through its
Draft Water Management Plan, CVWD had developed a system of policies and programs
designed to reduce domestic water use and increase the efficiency of that use to the greatest
extent feasible. The following briefly describes the major water conservation initiatives,
including applicable legislation.
Senate Bill x7-7
Senate Bill (SB) x7-7 (2009) includes several requirements to reduce water consumption and
increase water use efficiency statewide over the next decade. It mandates a 10% reduction in per
capita urban water use by year 2015, and a 20% reduction by year 2020. It further requires that
agricultural water suppliers prepare agricultural water management plans and develop efficient
water management practices. Finally, it requires that sustainable water supplies be expanded at
the regional level through the provision of incentives and alternative water supply sources, such
as desalination and stormwater recovery. 121
119 “Draft Coachella Valley Water District Water Management Plan”, prepared by Montgomery Watson Harza,
December 2010. 120 Personal communication, Mark Johnson, CVWD, December 20, 2010. 121 “SBX7 7 (Steinberg) – November 2, 2009 Fact Sheet”,
http://senweb03.senate.ca.gov/focus/outreach/sd23/200911enews/SBX77FactSheet.pdf California Senate Bill
(SB) x7-7, accessed via Google search, December 14, 2010.
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Water Efficient Landscaping
The California Water Conservation in Landscaping Act122 requires local jurisdictions to
implement a water efficient landscape ordinance, either through adoption of the jurisdiction’s
own or through implementation of the state ordinance, by January 1, 1993. Amendments enacted
in 2006 set forth more stringent requirements than those of the original legislation, with cities
and counties required to meet or exceed the new standards. The CVWD ordinance, adopted in
2003 and updated in 2007, requires that outdoor water use by new development be reduced by
25% beyond state requirements. In 2009, CVWD and other water districts in the Coachella
Valley, along with all Coachella Valley cities, Riverside County and the Coachella Valley
Association of Governments (CVAG), developed a single landscape ordinance for adoption by
each of these entities. The ordinance would encourage maximum efficiency for landscape water
use, establish uniform landscape standards throughout the Valley, and limit turf on new golf
courses. As such, it represents one of the most stringent such ordinances in the state.
The City has adopted the Water Efficient Landscape ordinance (No. 220, Chapter 8.13 in the
City Municipal Code), which implements the requirements of the state’s Model Efficient
Landscaping Ordinance123 and Water Conservation in Landscaping Act, including the more
stringent requirements of the ordinance developed in conjunction with CVWD. The City
ordinance is intended to establish effective water efficient landscape requirements for newly
installed and rehabilitated landscaping. It requires that new and rehabilitated landscape plans for
most residential, commercial and governmental projects are subject to City review, and must
include a water conservation concept statement and verification that the plan provides for water
efficient landscaping. Irrigation systems for existing landscaping may be subject to water audits
when water supply allowances are exceeded; it prohibits the overflow of waste water from
inefficient irrigation systems onto adjoining properties, and requires timely repair of broken or
malfunctioning sprinkler heads or pipes.
Conversion of Uses
The Draft WMP prepared by CVWD establishes goals to reduce groundwater demand for
agriculture and golf courses by converting portions of those uses to recycled or canal water. The
Draft WMP projects a decrease in groundwater demand by agricultural uses by 2045 of 89%
from 2009 levels. As of 2010, CVWD requires golf courses with access to recycled or canal
water to utilize these sources for at least 90% of their irrigation demand by 2015.
Other Water Supplies
CVWD’s Draft WMP describes other water supply sources that have been available in the past
or may be available in the future. These include recycled water from fish farm operations
(aquaculture), water transfer opportunities, desalinated drain and ocean water, and stormwater
capture. The Draft WMP discusses the relative feasibility of each of these options, some of
which may provide additional water supplies in future.
122 California Government Code, Sections 65591, 65593, 65596. 123 California Code of Regulations Title 23, Waters Division 2, Department of Water Resources Chapter 2.7,
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Integrated Regional Water Management Plan124
The Integrated Regional Water Management (IRWM) Planning Act, enacted in 2002,125
encourages the development of integrated regional strategies by local agencies to manage and
improve the quality, quantity and reliability of water supplies. IRWM plans are reviewed by the
California Department of Water Resources (DWR), which also funds water management
projects. The Coachella Valley Regional Water Management Group (CVRWMG) was formed in
2008 through a Memorandum of Understanding between CVWD and four other regional water
management agencies to develop a an Integrated Regional Water Management Plan. Through
the Plan, the Management Group will be eligible for DWR grants. The Plan has completed
public review and was adopted by the CVWD Board in December 2010.126
Urban Water Management Plan
California Water Code California Water Code mandates that CVWD prepare an Urban Water
Management Plan (UWMP) to analyze current and future water supplies and ensure sufficient
supply to serve land uses within its service area. CVWD’s previous UWMP was adopted in
2005127 and has subsequently been updated. The 2010 UWMP has been completed.
Water Quality
In the Coachella Valley, groundwater quality is affected by depth, hydrogeologic or cultural
features, such as proximity to faults or recharge basins, and the presence of contaminants. In
general, the Valley has generally good to excellent water quality. Exceptions occur in portions of
the Subbasin where perched or semi-perched water tables occur, where groundwater contains
high concentrations of dissolved solids. In some areas in the Planning Area, long-term discharge
associated septic systems may also affect groundwater quality. Importation of Colorado River
water has also impacted groundwater quality in some areas. These issues are further discussed
below.
The CVWD Draft WMP addresses existing and emerging issues associated with water quality in
the Coachella Valley. These include salinity and the presence of a variety of contaminants,
including total dissolved solids and nitrates. CVWD regularly monitors wells, and testing data
provided in the most recent Water Quality Report shows water supplies meet all state and federal
standards for drinking water. In some areas, low levels of naturally occurring arsenic have been
found. CVWD has three ion treatment facilities for arsenic removal; these are located in the
Mecca and Thermal areas. For the most part, water treatment in wells is limited to chlorination
to assure disinfection.128
124 “Draft Coachella Valley Water District Water Management Plan”, prepared by Montgomery Watson Harza,
December 2010. 125 California Water Code, Division 6 Part 2.2, §10530 et seq., as amended. 126 Personal communication, Mark Johnson, CVWD, December 20, 2010. 127 “Final Coachella Valley Water District Water Management Plan”, prepared by Mongomery Watson Harza,
December 2005. 128 “Coachella Valley Water District Development Design Manual,” prepared by Coachella Valley Water District,
2010.
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Nitrates and total dissolved solids are briefly discussed below.
Total Dissolved Solids
Total Dissolved Solids (TDS) naturally leach into groundwater from soils. The secondary MCL
for TDS includes an upper level of 1,000 milligrams per liter (mg/L) and a short-term level of
1,500 mg/L. Based on CVWD domestic well monitoring data for 2009, TDS levels ranged from
150 to 980 mg/L.
Nitrates
The most closely monitored chemical in drinking water is nitrate. Nitrate is a nitrogen
compound, and the most common sources in groundwater include leaching of nitrogen-based
fertilizers, animal waste and natural deposits such as mesquite hummocks or alluvial fan
formations. Nitrates may also result from septic tank discharges. These compounds are often
found in shallower aquifer zones and may result from activities such as recharge, pumping, and
overdraft reduction.129
In drinking water, nitrate levels over 45 mg/L pose a health risk for infants younger than six
months old, as well as pregnant women and certain other specific conditions. Nitrate levels do
not demonstrate rapid change, given well depths. Should nitrate levels show an increase, CVWD
increases frequency of monitoring and is prepared to remove wells from service where indicated.
Data from CVWD 2009 well monitoring shows that average nitrate levels ranged from 2.1 to 7.1
mg/L.130 Concentrations as high as 39 mg/L were detected in samples taken from wells serving
the Cove Communities, which includes portions of La Quinta.
Impacts of Septic Systems on Groundwater Quality
Impacts on groundwater quality from long-term discharge from septic systems are more recent
and generally less extensive as compared with other water quality issues. However, CVWD, the
Regional Water Quality Control Board, and the Riverside County Department of Health
acknowledge that groundwater quality may be impacted by these discharges. There are a variety
of factors that influence impacts to groundwater from septic systems. These include population,
relative density, wastewater volume, soil conditions and septic system maintenance. Where large
populations at high densities are present, and where septic systems are poorly maintained,
impacts are generally greater. The removal of wastewater through community sewer systems
provides safeguards to protect groundwater resources from nitrate contamination. The majority
of residential development in the Planning Area is served by existing sanitary sewer facilities.
However, some areas, especially in the Sphere of Influence, still utilize septic systems. As future
development builds out, sewer systems will be extended to serve these areas and septic systems
will be abandoned.
129 “Draft Coachella Valley Water District Water Management Plan”, prepared by Montgomery Watson Harza,
December 2010. 130 “Coachella Valley Water District 2011 Domestic Water Quality Summary, in the CVWD 2011 Domestic Water
Quality Report.”
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Water Quality Regulation
There are a variety of federal and state laws and regulations that are intended to assure the
adequate planning, implementation and enforcement of water quality control effort. On a federal
level, the primary pieces of legislation are the Clean Water Act and the National Environmental
Policy Act (NEPA). Water quality statutes and administrative laws enacted by the State of
California include the California Water Code, California Environmental Quality Act (CEQA)
and California Code of Regulations. Health and Safety Code, Fish and Game Code and Public
Resources Code also include applications to water quality.
California Water Code (Section 13260), states that “any person discharging waste or proposing
to discharge waste that may affect waters of the State, except to a community sewer system” is
required “to file a report of waste discharge with the regional board of that region” where
densities exceed two (2) dwelling units/acre. For commercial and industrial wastewater
generators where discharge volumes exceed certain thresholds, these requirements also apply.
The California Regional Water Quality Control Board (CRWQCB), Colorado River Basin
Region, implements federal and state laws and regulations pertaining to water quality. The
CRWQCB has prepared a Water Quality Control Plan for the Colorado River Basin, which was
adopted in 1993. The plan is subject to periodic review by the State Water Quality Control Board
and the US Environmental Protection Agency, and the Regional Board updates it as needed. In
compliance with the federal Clean Water Act, the CRWQCB is also required to list water bodies
that exceed or are expected to exceed water quality standards even with implementation of water
quality control standards. Those affecting the Coachella Valley in the most current listing
include the Coachella Valley Stormwater Channel and the Salton Sea. The Board sets specified
time limits by which it will develop total maximum daily loads (TMDL) to limit the discharge of
pollutants and thereby remedy water quality impairment for specified pollutants. TMDL
completion dates for the Stormwater Channel range from 2014 to 2021.
The primary water quality issues in the Coachella Valley are salinity and nitrates. In addition to
addressing issues regarding septic and sewer systems, the CRWQCB oversees concerns about
the Whitewater River and other sources of surface water. CRWQCB monitors illegal discharges
of human or animal waste, leaking fuel storage tanks, and unauthorized hazardous and toxic
materials dumping sites.
National Pollutant Discharge Elimination System
The National Pollutant Discharge Elimination System (NPDES) was adopted in 1990 to
implement the federal Clean Water Act. NPDES requires that local jurisdictions adopt and
implement storm water management plans and programs to “effectively prohibit non-storm water
discharge into the storm drain and require controls to reduce the discharge of pollutants from
storm water systems to waters of the United States to the maximum extent possible.” CEQA
analysis is not required for pollutant control measures. The La Quinta Department of Public
Works manages the NPDES program for the City.
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2. Project Impacts
At build out, the proposed General Plan will result in 53,103 dwelling units. As compared with
the previous General Plan, which planned for 78,952 units, this represents a decrease of
approximately 25,849 units, or 32.7%. As a result of new residential development in the
Planning Area, it is expected that a population of approximately 134,352 will be generated at
build out. New commercial, industrial, public facilities and other types of development will also
occur as a result of implementation of the proposed General Plan. The proposed Land Use Plan
for the General Plan would result in less overall development as compared with the previous
General Plan. Build out of the new residential and other types of development will result in an
increase in water consumption compared to existing conditions, which has the potential to
impacts water resources.
Water Demand Analysis
A Water Supply Study (WSS)131 has been prepared for the La Quinta General Plan and is
included in Appendix I of this EIR. The WSS estimates current water demands generated within
the Planning Area and projects future water demands that will be generated at build out of the
proposed General Plan. It should be noted that the WSS prepared for the General Plan is
programmatic, and qualifying individual development projects within the Planning Area may be
subject to preparation of project-level Water Supply Assessments as warranted.
Existing Water Demands
Table III-51 shows the estimated water demands that are currently generated within the Planning
Area. Methodology and assumptions utilized to estimate the existing water demands within the
Planning Area are described in Appendix A of the WSS, which is included in full in Appendix I
of this EIR.
131 “Water Supply Study for the proposed La Quinta General Plan Update 2010,” prepared by Terra Nova Planning
& Research, June 21, 2011.
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Table III-51
Estimate of Existing Water Service Demands
Land Use Designation
Landscaping
(ac-ft/yr)
Potable
(ac-ft/yr)
Total Demand
(ac-ft/yr)
Daily Demand
(mgd)
La Quinta City Limits
Low Density Residential 6,482.65 4,091.66 10,574.31 9.44
Medium/High Density Residential 1,157.40 521.42 1,678.83 1.5
Commercial 311.87 1,007.61 1,319.48 1.18
Major Community Facilities 295.91 111.99 407.9 0.36
Open Space - Natural N/A N/A - -
Open Space- Recreation 16,465.48 N/A 16,465.48 14.7
Streets, Sidewalks, Medians 781.47 N/A 781.47 0.7
Total 25,494.78 5,732.69 31,227.46 27.88
Sphere of Influence
Low Density Residential 857.11 157.31 1,014.42 0.91
Medium/High Density Residential 0.18 - 0.18 0
Commercial 17.71 43.03 60.74 0.05
Major Community Facilities 30.65 13.26 43.9 0.04
Streets, Sidewalks, Medians 149.17 N/A 149.17 0.13
Total 1,054.82 213.6 1,268.42 1.13
Planning Area Summary
Low Density Residential 7,339.76 4,248.97 11,588.73 10.35
Medium/High Density Residential 1,157.58 521.42 1,679.01 1.5
Commercial/Industrial 329.58 1,050.64 1,380.22 1.23
Major Community Facilities 326.56 125.25 451.81 0.4
Open Space - Natural N/A N/A - -
Open Space- Recreation 16,465.48 N/A 16,465.48 14.7
Streets, Sidewalks, Medians 930.64 N/A 930.64 0.83
Total 26,549.59 5,946.28 32,495.88 29.01
Source: "La Quinta General Plan Water Resources Projections," Appendix A to Water Supply Assessment, prepared by Terra Nova
Planning & Research Inc., January 2011.
As seen in the Table above, the existing water demands for the La Quinta Planning Area are
estimated to be 32,496 acre-feet per year, consisting of 31,227 acre-feet within City limits and
1,268 acre-feet within the Sphere of Influence. Existing water demands in the Planning Area are
comprised of 3.9% within the Sphere and 96.1% within City limits.
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Water Demands at Build Out (2035)
The following table shows the projected water demand for land uses in the City, Sphere and the
entire planning area at build out, assuming that new development adheres to water efficiency
building standards and existing development continues to generate business as usual water
demands.
Table III-52
Estimate of Water Service Demands at Build Out
Land Use Designation
Landscaping
(ac-ft/yr)
Potable
(ac-ft/yr)
Total Demand
(ac-ft/yr)
Daily Demand
(mgd)
La Quinta City Limits
Low Density Residential 9,294.22 4,881.63 14,175.85 12.66
Medium/High Density Residential 1,502.34 1,016.81 2,519.15 2.25
Commercial 496.72 1,360.39 1,857.11 1.66
Major Community Facilities 476.80 149.64 626.44 0.56
Open Space - Natural N/A N/A N/A N/A
Open Space- Recreation 17,681.77 N/A 17,681.77 15.79
Streets, Sidewalks, Medians 922.39 N/A 922.39 0.82
Total 30,374.25 7,408.47 37,782.72 33.73
Sphere of Influence
Low Density Residential 12,309.74 3,375.02 15,684.76 14.00
Medium/High Density Residential 24.21 34.41 58.62 0.05
Commercial 192.99 377.52 570.51 0.51
Major Community Facilities 32.47 13.63 46.10 0.04
Streets, Sidewalks, Medians 324.17 N/A 324.17 0.29
Total 12,883.57 3,800.58 16,684.15 14.89
Planning Area Summary
Low Density Residential 21,603.95 8,256.66 29,860.61 26.66
Medium/High Density Residential 1,526.55 1,051.22 2,577.77 2.30
Commercial/Industrial 689.71 1,737.91 2,427.62 2.17
Major Community Facilities 509.27 163.27 672.54 0.60
Open Space - Natural N/A N/A - -
Open Space- Recreation 17,681.77 N/A 17,681.77 15.79
Streets, Sidewalks, Medians 1,246.56 N/A 1,246.56 1.11
Total 43,257.82 11,209.05 54,466.87 48.62
Source: "La Quinta General Plan Water Resources Projections," Appendix A to Water Supply Assessment, prepared by Terra Nova
Planning & Research Inc., January 2011.
As seen in the Table above, the build out water demands for the La Quinta Planning Area are
estimated to be 54,467 acre-feet per year, consisting of 37,783 acre-feet within City limits and
16,684 acre-feet within the Sphere of Influence. Build out water demands in the Planning Area
are comprised of 30.6% within the Sphere and 69.3% within City limits.
Proposed Development
At build out development within the La Quinta Planning Area is expected to consume 54,467
acre-feet of water per year, which represents an increase in water demand of approximately
21,971 acre-feet compared to water demands generated by existing development. The Table
below shows the projected water demand that will be generated from new development set forth
in the proposed General Plan Update.
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Table III-53
Estimate of Water Service Demands from New Development
La Quinta
Landscaping
(ac-ft/yr)
Potable
(ac-ft/yr)
Total Demand
(ac-ft/yr)
Daily Demand
(mgd)
City Limits 4,879.47 1,675.78 6,555.26 5.85
Sphere of Influence 11,828.75 3,586.98 15,415.73 13.76
Planning Area Summary 16,708.23 5,262.77 21,970.99 19.61
As seen in the Table above, 70% of the new water demand will be generated by new developed
within the Sphere, and 30% will be generated by new development within City Limits.
Water Demand Consistency
CVWD’s 2010 UWMP accounts for new growth and development that is expected to occur
within the region including the Planning Area. Section 3.3 of the WSS describes the water
demand projections for the La Quinta General Plan Update relative to the water demand
projections set forth in the CVWD UWMP. The average per capita water demand for the CVWD
Service Area is approximately 482 gallons per capita per day (gpcd) for 2010 and is projected to
be 423 gpcd for 2035. The 2010 per capita water demand for the La Quinta Planning Area is
approximately 473 gallons per day and is projected to be 361 gpcd in 2035. The water demand
estimates for the La Quinta Planning Area for 2010 and 2035 are 2% and 15% more efficient
compared to the CVWD estimates. As such, water demands generated by the La Quinta Planning
Area are fully captured and accounted for within the CVWD UWMP projections. Therefore,
water demand projections proposed by the La Quinta General Plan Update are consistent with
the water demand estimates utilized by CVWD.
Impacts to Water Supply Resources
As described above, CVWD serves as the water provider for the City of La Quinta and the
Sphere. Water supplies that serve the existing La Quinta Planning Area are derived from
groundwater in storage and imported Colorado River water and SWP exchange water. All urban
water demands are currently met through groundwater supplies. New water demands generated
by proposed development set forth in the La Quinta General Plan Update will be met through a
combination of groundwater, imported supplies, and recycled water.
CVWD expects to have sufficient water supplies to serve development in the Planning Area
through 2035 and beyond by utilizing a combination of water supply sources and treating surface
water supplies to potable quality standards. CVWD projects that, in 2035, the urban water
demand will be supplied by a total of 242,700 acre-feet per year consisting of 53% groundwater,
20% treated Colorado River Water, 22% Untreated Colorado River Water, and 4% desalinated
agricultural drain water.
CVWD’s UWMP and the WMP provide long term water supply/demand planning in an effort to
protect water resources, preserve water quality, and assure that water supplies are available to
meet demands. CVWD’s UWMP evaluates water demands relative to supplies for the period
between 2010 and 2035 under normal, single, and multiple dry year conditions. The UWMP
finds that with groundwater supplies, imported water supplies, water conservation programs, and
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recharge activities water supplies are sufficient to meet demands during normal, single, and
multiple dry year conditions through 2035.
Implementation of new growth and development set forth under the proposed General Plan will
result in an increase in the demand for water of approximately 6,555 acre-feet within City Limits
and 15,416 acre-feet within the Sphere of Influence by 2035. This new demand will be met by
groundwater, imported Colorado River water, desalinated agricultural drain water, or a
combination thereof. As described above, CVWD has accounted for this increased water demand
in conjunction with all other projected water demands within the service area and has determined
that through the utilization of a combination of water supply sources sufficient water supplies
will be available to meet demands in 2035. As such, the level of additional water supplies needed
to meet demands generated by development within City Limits and the Sphere at build out of the
General Plan will not substantially deplete groundwater reserves or interfere with groundwater
recharge.
The City of La Quinta relies on CVWD to manage and supply water resources. Nonetheless, the
City is committed to promoting water conservation and achieving water savings, protecting
groundwater reserves, and preserving groundwater quality. In the La Quinta Planning Area water
conservation can be achieved through retrofitting existing development, installing water efficient
appliances, the use of new technology, and advanced irrigation control for outdoor landscaping.
Source Substitution
At build out, 20% (11,209 acre-feet) of the water demands within the Planning Area will be
generated by potable demands whereas 80% (43,258 acre-feet) will be generated by non-potable
demands, such as landscaping. The use of non-potable water supplies for the irrigation of
recreational open space, especially golf course development, as well as other landscaped area
protects groundwater reserves by utilizing an alternative water supply source.
Water Resources and Climate Change
The region’s water supply consists of both surface and groundwater supplies, which have
varying susceptibility to climate change. Surface water supplies are especially susceptible to
increasing temperatures that are associated with changing climatic conditions. Groundwater
reserves tend to be somewhat protected from climate change since they are underground and are
not susceptible to increased evaporation due to elevated temperatures. As such, CVWD’s long
term water management strategy relies on conjunctive use thereby maximizing the use of surface
flows when they are available including use of surface water to recharge the groundwater basin,
and the use of banked groundwater supplies when surface flows are limited or unavailable.
Given the substantial amount of uncertainty associated with predicting the affect that climate
change will have on water resources, CVWD continuously monitors inflows and outflows in the
basin, implements programs to conserve water, recharge the basin, and protect water resources,
and routinely updates planning and management strategies to incorporate the latest available
information and technologies.
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Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
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Water Quality
The quality of water within the Whitewater River Subbasin and both treated and untreated
Colorado River water is described as good in the CVWD UWMP (Table 5-13). The 2011 Water
Quality Report prepared by CVWD shows the domestic water quality by service area.
Monitoring for certain contaminants has been conducted and no established thresholds for
domestic water quality standards have been exceeded within the CVWD service area. The
primary groundwater quality concerns in the Whitewater River Subbasin are salinity and
nitrate.132 Arsenic, perchlorate, chromium-6, uranium, carcinogens, and endocrine disrupting
compounds have been identified as emerging issues and are monitored by CVWD. 133
Salinity
Colorado River water is used for direct recharge to groundwater reserves and is relatively high in
salinity. Salinity levels of surface water supplies within the service area range from an average of
636 mg/L to of 790 mg/L. CVWD is evaluating and pursuing several options to limit the
concentration of salt in recharge supplies. One option is to directly import SWP supplies via
construction of a SWP extension pipeline that would connect to the Whitewater and Mission
Creek spreading facilities. SWP supplies typically have an average total dissolved solids
concentration of 245 mg/L. Other option is to treat Colorado River water through a desalination
process before recharge, although this option may be cost prohibitive. CVWD will continue to
monitory TDS in recharge supplies and groundwater. With implementation of the CVWMP
salinity will not affect groundwater supply reliability.
Nitrates
Groundwater quality may also be adversely impacted by long-term discharge from on-lot septic
systems. These impacts to groundwater quality are expected to be greatest where septic systems
serve large populations in high densities, such as the La Quinta cove community. For the City of
La Quinta, nitrate concentrations in domestic water provided by CVWD range from “not
detected” to a maximum of 40 mg/L. The average nitrate concentration was 7 mg/L within the
La Quinta service area. The MCL for nitrate has been set at 45 mg/L. Although domestic water
delivered by CVWD was below this threshold, the maximum concentration was approaching the
threshold. Nitrates in the groundwater supply are attributed to leaching of fertilizers, animal
waste, and natural deposits. Expanding the sewer system and removing on-lot septic may further
limit nitrate accumulation in groundwater reserves.
Water Quality Impacts
Impacts to water quality are expected to be comparable to or slightly less than those associated
with the 2002 General Plan. The proposed General Plan provides for fewer residential units and
overall less commercial and industrial square footage than does the 2002 General Plan.
A majority of the new development in the Planning Area will be required to connect to
community sewer facilities and, over time, it is expected that lots currently using septic systems
132 “CVWD 2011 Domestic Water Quality Table,” prepared by CVWD, 2011. 133 Refer to section 4.5.2 of the Water Supply Study for additional information on emerging pollutants of concern.
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will be provided with the opportunity to connect to sanitary sewer facilities, thereby reducing the
potential for nitrate leaching.
The proposed General Plan is not expected to impact water quality from project implementation.
However, to further limit potential impacts to water resources and reduce impacts to less than
significant levels the following mitigation measures are proposed. Further, implementation of the
proposed General Plan will ensure the continued implementation of federal, state, local and all
other applicable pollution control standards.
3. Mitigation
Water Conservation
Increasing demands on water supplies in the General Plan Area require the implementation of
short and long-term water conservation efforts to ensure the continued availability of this
resource. Reduction in per capita consumption as well as water-efficient landscaping design and
management are among the best conservation opportunities. The City’s Water efficient landscape
ordinance prohibits washing driveways and walkways with water, excessive runoff of landscape
irrigation water, and other wasteful water practices. It establishes penalties when these
requirements are violated. There are a variety of state and regional mandates in place intended to
reduce urban water consumption over the next several decades. As previously noted, new state
requirements mandate a 10% reduction in per capita urban water use by year 2015, and 20%
reduction by year 2020. The CVWD water efficient landscape ordinance, on which the City
ordinance is based, requires that outdoor water use by new development be reduced by 25% over
mandated state levels. Further, the CVWD Draft WMP requires that golf course users with
access to canal or recycled water convert at least 90% of their irrigation water use to those
sources by 2015.
General Mitigation Measures
Groundwater subareas are not defined by jurisdictional boundaries. The issues of groundwater
depletion and contamination addressed herein are regional and local issues. Therefore, in
Southern California, the efficient use and increased conservation of water will continue to be
critical issues to be considered in community planning and development. The City and CVWD
must continue to collaborate to protect and manage water resources.
There are a variety of goals, policies, and programs included in the proposed City General Plan
update that are intended to ensure the continued availability of a dependable supply of safe, high-
quality domestic water for all community segments. The following mitigation measures shall be
implemented to reduce the potential impacts to water resources associated with implementation
of the proposed General Plan to less than significant levels:
1. The City shall coordinate and cooperate with CVWD to ensure City-wide compliance
with State Senate Bill x7-7 by implementing policies to reduce per capita urban water use
by 10% by year 2015, and 20% reduction by year 2020, including landscaping
conversion programs and the smart irrigation control program; expanding the availability
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Section III. Existing Environmental Concerns, Project Impacts, and Mitigation Measures
III-257
of sustainable water supplies such as tertiary treated water, and encouraging its use for
landscape irrigation purposes, especially for irrigating golf courses and other large
landscaped areas.
2. The City should review and amend its Development Standards to require that all new
development demonstrate a reduction of domestic water consumption equivalent to the
CalGreen Tier One standards in effect at the time of development.
3. The City shall continue to implement its Water Efficient Landscape ordinance by
requiring that City and private sector development projects implement water efficient
landscaping plans to meet or exceed current water efficiency standards.
4. The City shall require that new development reduce its projected water consumption over
“business as usual” consumption rates.
5. In conjunction with the Coachella Valley Water District as well as independently, the
City shall develop programs to allow and encourage the retrofitting of existing water-
intensive appliances and irrigation systems in existing development.
6. The City and Coachella Valley Water District shall review future development proposals
that propose to convert agricultural uses to urban development to ensure that non-potable
water is used for irrigation purposes, and that new irrigation systems utilize existing
agricultural drainage and irrigation water delivery facilities to the greatest extent feasible.
7. The City shall continue to require that all new developments use water conserving
appliances and fixtures, including low-flush toilets and low-flow showerheads and
faucets, as well as the application of water-conserving technologies in conformance with
Section 17921.3 of the Health and Safety Code, Title 20, California Administrative Code
Section 1601(b), and applicable sections of Title 24 of the State Code.
8. The City shall continue to encourage that new development use faucets, showerheads and
appliances in new development that exceed Title 20 and Title 24 water efficiency
requirements.
9. The City shall, prior to approval of development plans, require that qualifying future
development in the General Plan Area have an adopted Water Supply Assessment in
compliance with AB 610 and 221.
10. To the greatest extent practicable, the City shall require new development to connect to
the community sanitary sewer system.
11. The City shall review and amend its Development Standards and Review Procedures to
ensure coordination with the Coachella Valley Water District and to assure that existing
sewer service along with the extension of sewer service is capable of meeting the needs
of current and future development.
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12. To the greatest extent feasible, the City shall coordinate with the Coachella Valley Water
District to encourage the elimination of septic systems where they occur within the City.
Mitigation Monitoring and Reporting
A. The Planning Department and the City Engineer shall review all development proposals to
evaluate their potential for adverse impacts on water quality and quantity, and shall require
all development to mitigate any significant adverse impacts.
Responsible Parties: Planning Department, City Engineer, Coachella Valley Water
District, project developer.
B. The City shall continue to coordinate and cooperate with the Coachella Valley Water
District to ensure that the groundwater aquifer is protected from excessive extraction.
Responsible Parties: Planning Department, City Engineer, Coachella Valley Water District.
Terra Nova/La Quinta General Plan EIR
Section IV. Unavoidable Significant Impacts
IV-1
LA QUINTA GENERAL PLAN
ENVIRONMENTAL IMPACT REPORT
IV. UNAVOIDABLE SIGNIFICANT IMPACTS
An assessment of potential environmental impacts associated with implementation and build out
of the La Quinta General Plan Update was provided in Section III of this EIR. The analysis led to
a determination of the level of impact on each environmental resource, including no impact, less
than significant impact, less than significant with mitigation, or potentially unavoidable
significant impact as a result of build out of the General Plan. This section summarizes those
impacts that are potentially unavoidable. Even with the imposition of mitigation measures,
impacts to the following categories will remain significant and are unavoidable.
Air Quality
Implementation of the General Plan Update will result in significant air quality impacts in the La
Quinta Planning Area. Air pollutants will be generated from a variety of activities, including
grading and construction, vehicle emissions, and daily operations. Emissions generated by
vehicular traffic are projected to be the greatest source of air pollutants. The use of natural gas
and electricity for operation of existing and new buildings and structures will also result in the
emission of air pollutants.
Construction Emissions
Air quality emissions from construction activities will occur as a result of new development
within the City limits and Sphere of Influence. As discussed in Section III of this EIR, emissions
from construction within the City are projected to remain below established thresholds for all
criteria pollutants expect for NOx and ROG. As shown in Section III, approximately 122 pounds
per day of NOx and 818 pounds per day of ROG are expected even with the implementation of
mitigation measures. This is well above the 75 pound per day threshold established by
SCAQMD. As such air quality emissions from NOx and ROG’s during construction activities
within City limits have the potential to result in significant and unavoidable impacts.
Construction related air quality emissions from the development of lands within the Sphere of
Influence are projected to exceed established daily thresholds for NOx and ROG, even with
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Section IV. Unavoidable Significant Impacts
IV-2
implementation of mitigation measures. As shown in Section III of this EIR, approximately 104
pounds per day of NOx, and 697 pounds per day of ROG have the potential to occur during
construction activities. This is above the SCAQMD thresholds of 100 pounds per day for NOx,
and 75 pound per day for ROG. Air quality emissions from NOx and ROG during construction
activities within the Sphere of Influence have the potential to result in significant and
unavoidable impacts.
Air pollutant emissions from construction activities are temporary and will end once construction
is complete. Nonetheless, during construction activities and assuming simultaneous construction
of vacant lands within the Planning Area, the proposed General Plan Update has the potential to
result in a cumulatively considerable net increase of NOx and ROG. Should construction
activities in the City and Sphere occur simultaneously at the rates assumed in Section III,
emissions of PM2.5 and PM10 will also exceed thresholds of significance, at 261 and 58 pounds
per day, respectively. Projections of these criteria pollutants exceed established daily thresholds
and have the potential to result in significant and unavoidable impacts for these criteria
pollutants.
Operation Emissions
For operation of the General Plan Update, air quality emissions have the potential to result in a
cumulatively considerable net increase of all six criteria pollutants, including CO, NOx, SOx,
PM10, PM2.5, and ROG, as well as greenhouse gas emissions. Emissions of air quality pollutants
from operation include the use of electricity and natural gas, as well as area source and moving
source emissions. Projections of these pollutants exceed established daily thresholds and have
the potential to result in significant and unavoidable impacts.
Emission from the consumption of electricity will primarily occur offsite, where electricity is
generated. As such, the Planning Area will be indirectly impacted by these emissions.
Nonetheless, the Planning Area is responsible for generating the electricity demand. While it is
expected that the electricity grid mix will incorporate more renewables in future years, the use of
coal and natural gas fired power plant will contribute significant emissions generated by the
onsite energy demand.
Natural gas generation facilities and onsite use of natural gas for cooking, heating, and other uses
will result in significant impacts. Although some of these emissions may not occur within the
Planning Area, as no such generating facilities exist within the planning area, the emission
projections result in a considerable increase, with significant impacts.
While implementation of the proposed mitigation measures and Greenhouse Gas Reduction Plan
may be effective in substantially reducing emissions to levels below significance for certain
sectors, emissions from moving sources will remain significant and are unavoidable.
The City has varying levels of control over the avoidance of emissions. Although the EIR sets
forth all feasible mitigation measures and a comprehensive Greenhouse Gas Reduction Plan has
been prepared, air quality emissions may remain significant and unavoidable. Regardless of
mitigation measures, development of the General Plan will contribute to cumulative air quality
impacts locally and regionally. Although emissions can be mitigated to a certain degree,
Terra Nova/La Quinta General Plan EIR
Section IV. Unavoidable Significant Impacts
IV-3
significant and unavoidable impacts to air quality, including greenhouse gas emissions, will
occur as a result of development of the General Plan.
The implementation of mitigation measures for project-specific proposals is an effective means
to reducing air quality impacts for the entire General Plan area. Design features that result in
minimal trip generation, increase the use of green building design and technologies, provide
alternative transportation options and onsite features such as electric charging station, and
incorporate the use of alternative energy sources both locally and regionally through
technologies such as individual and region-wide solar roof installation projects and region-wide
wind farm development, will reduce the emissions associated with build out of the Planning
Area. These measures will not only reduce emissions of criteria pollutants, but will also reduce
emissions of greenhouse gases.
Traffic
The consequences of General Plan build out have been evaluated for the 63 major roadway
segments and 37 intersections. Based on this analysis, the proposed General Plan is projected to
generate a total of approximately 635,905 average daily trips. Of these, 449,489 ADT would be
generated within the City's corporate limits and 186,416 would be generated in the City Sphere-
of-Influence.
Within the City's corporate limits, the proposed Land Use Plan will generate about 3.6% more
traffic than build out of the 2002 General Plan. Within the City's Sphere, the proposed Land Use
Plan will generate about 34% more traffic than build out of the 2002 General Plan land use
designations.
The majority of the roadway segments are forecast to operate at acceptable levels of service (V/C
ratios less than or equal to 0.90 or LOS D or better). Three segments are projected to operate at
LOS E and three at LOD F at 2035 build out.
Washington Street segments between Avenue 42 and Miles Avenue and between Highway
111 and Eisenhower Drive (6-lane Major Arterial) are forecast to exceed theoretical
maximum carrying capacity by up to 3,000 VPD with the most problematic segment between
Fred Waring Drive and Miles Avenue. LOS D service volumes are exceeded by over 9,000
VPD.
Madison Street between Avenue 54 and Airport Boulevard (4-lane Primary Arterial) is
forecast to exceed theoretical maximum carrying capacity by approximately 4,900 VPD.
LOS D service volumes are exceeded by over 9,000 VPD.
Harrison Street between Airport Boulevard and Avenue 58 (8-lane Augmented Major) is
forecast to exceed theoretical maximum carrying capacity by approximately 3,800 VPD.
Although the capacity of Harrison Street was assumed to be that of an Augmented Major
Road (76,000 vehicles per day), it would likely operate as an Expressway due to limited
accessibility compared to an Augmented Major Road, thus carrying a larger capacity. Prior
study by the County raised the potential of grade-separated intersections to further enhance
capacity.
Terra Nova/La Quinta General Plan EIR
Section IV. Unavoidable Significant Impacts
IV-4
Of the 37 intersections analyzed, the following four are not expected to be able to accommodate
all the required build out improvements and therefore have the potential to be operating at
unacceptable levels of service by 2035 General Plan build out:
Washington Street @ Fred Waring Drive;
Adams Street @ Miles Avenue;
Jefferson Street @ Highway 111;
Madison Street @ Avenue 50.
It should also be noted that three of the four impacted intersections are shared between more than
one jurisdiction. For instance, the Washington Street/Fred Waring Drive intersection is located
within the corporate boundaries of the cities of La Quinta, Palm Desert and Indian Wells. In
these cases, close and on-going coordination between cities will be necessary to provide
optimum intersection improvements and to otherwise address forecast operational deficiencies.
However, even with the implementation of feasible mitigation measures, impacts will be
significant and unavoidable.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-1
LA QUINTA GENERAL PLAN
ENVIRONMENTAL IMPACT REPORT
V. PROJECT ALTERNATIVES
Introduction A.
Impacts associated with build out of the various alternatives to the proposed General Plan Update
are considered in this section of the EIR. A wide range of potential impacts, such as land use,
traffic and circulation, soils and geology, air and water quality, hydrological issues, biological
and cultural resources, and population and housing, are considered in Section III.
The potential impacts associated with the same range of issues that are evaluated in Section III
are discussed in this section for three additional General Plan scenarios, as follows: “No Project”
Alternative (2002 General Plan); Alternative I General Plan Scenario; and Alternative II. The
land use assumptions for each alternative are described in Section V.C., below.
Table V-1 illustrates the land use build out summary for the Preferred Alternative. The build out
summaries for each of the alternatives are illustrated below.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-2
Table V-1
Preferred Alternative
Build Out Summary: City Limits
Land Use Designation Developed Vacant Total Existing
Units
Potential
Units
Total Units
Low Density Residential 4,006.0 1,583.7 5,589.7 20,834 4,751 25,585
Medium/High
Density Residential
1,292.4 373.6 1,666.0 2,655 3,362 6,017
Residential Subtotal 5,298.4 1.957.3 7,255.7 23,489 8,114 31,603
Existing
SF
Potential
SF
Total SF
General Commercial 385.6 184.0 569.6 3,695,282 1,763,309 5,458,591
Tourist Commercial 206.6 138.9 345.5 1,979,889 1,331,106 3,310,996
Village Commercial 77.1 12.9 90.0 738,865 123,623 862,488
Commercial Subtotal 669.3 335.8 1,005.1 6,414,036 3,218,039 9,632,074
Major Community
Facilities
252.7 193.8 446.5
Open Space - Natural 2,171.6 4,761.7 6,933.3
Open Space - Recreation 4,392.2 867.0 5,259.2
Street Rights-of-Way 1,764.6 191.1 1,955.7
Grand Total 14,548.8 8,306.7 22,855.5
Table V-2
Preferred Alternative
Build Out Summary: Sphere of Influence
Land Use Designation Developed Vacant Total Existing
Units
Potential
Units
Total Units
Low Density Residential 551.5 6,826.6 7,378.1 801 20,480 21,281
Medium/High
Density Residential
0.2 24.4 24.6 - 219 219
Subtotal 551.7 6,851.0 7,402.7 801 20,699 21,500
Existing SF Potential SF Total SF
General Commercial 28.6 256.6 285.1 273,760 2,458,797 2,732,557
Industrial/Lgt. Mfg. 0 63.8 63.8 - 611,408 611,408
Major Community Facilities 28.17 1.61 29.8
Street Rights-of-Way 319.93 0 319.9
Grand Total 928.4 7,173.0 8,101.4
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-3
Table V-3
Preferred Alternative
Build Out Summary: Entire Planning Area
Land Use Designation Developed Vacant Total Existing
Units
Potential
Units
Total Units
Low Density Residential1,3 4,557.5 8,410.3 12,967.8 21,635 25,231 46,866
Medium/High Density2,3
Residential
1,292.6 398.0 1,690.6 2,655 3,582 6,236
Total 5,850.1 8,808.3 14,658.4 24,290 28,813 53,103
Existing SF Potential SF Total SF
General Commercial 414.2 440.6 854.7 3,969,042 4,222,106 8,191,148
Tourist Commercial 206.6 138.9 345.5 1,979,889 1,331,106 3,310,996
Village Commercial 77.1 12.9 90.0 738,865 123,623 862,488
Total4 697.9 592.4 1,290.2 6,687,796 5,676,835 12,364,631
Industrial/Lgt. Mfg. 0.0 63.8 63.8 - 611,408 611,408
Major Community Facilities 280.9 195.4 476.3
Open Space - Natural 2,171.6 4,761.7 6,933.3
Open Space - Recreation 4,392.2 867.0 5,259.2
Street Rights-of-Way 2,084.5 191.1 2,275.6
Grand Total 15,477.2 15,479.7 30,956.9
1 Includes single-family attached and detached housing units. 2 Includes single-family attached and detached and multi-family housing units. 3 Future residential development is assumed to occur at 75% of the maximum density permitted. 4 Assumes 22% lot coverage for commercial and industrial development. Assumes 70% of TC and VC developed as
commercial.
Statement of Project Objectives B.
The City of La Quinta developed a Vision for the General Plan Update, and prepared Guiding
Principles for the General Plan, as follows:
A Neighborhood Oriented Community – Strive to ensure that existing and future housing for
all residents continues to be diverse in type and of high quality. Establish and maintain
connections between existing and future neighborhoods, including existing housing stock and
associated infrastructure.
A Healthy, Vibrant and Heritage Minded Community – Ensure parks, public facilities and
open spaces are appropriately sized and designed to meet the needs and interests of all
segments of the community. Continue to ensure that all land uses cohesively exist with the
area’s natural, cultural and historical heritage.
A Fiscally Sound Community – Capitalize on our unique development opportunities,
especially within the Highway 111 Corridor and the Village area by focusing on shopping,
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-4
dining, entertainment, professional and mixed use options while improving the aesthetics of the
community.
A Safe Community – Continue to enforce development standards that promote safe indoor
and outdoor spaces and provide emergency services that are adequately funded, staffed, and
equipped to provide timely response.
A Full Service Community – Ensure that streets, water and sewer systems, storm drains, and
other infrastructure is maintained in good working order and of adequate service level to
address existing and future needs.
A Resort Oriented Community – Maintain and improve the opportunities for La Quinta to be
recognized, both nationally and internationally, as a top resort and recreation destination.
A Circulation Minded Community – Promote and encourage a broad range of transportation
opportunities, especially those that reduce the impact to our environment, as well as effectively
moving people and goods. Continue to work closely with neighboring communities and
regional agencies to address regional transportation issues.
A Conservation Focused Community – Promote and encourage the efficient use of energy
and water; minimize air and water pollution; reduce noise and light pollution; preserve native
habitat; reduce litter; and increase recycling programs.
These Guiding Principles form the basis for the Project Objectives described below.
1. The preservation and enhancement of the City’s quality of life.
2. The preservation and enhancement of existing neighborhoods.
3. A balance of housing types to accommodate the needs of all current and future
residents.
4. The build out of a wide-ranging economic base providing jobs and sufficient revenues
to maintain the high levels of services the City has been able to provide its residents.
5. The development of comprehensive transportation system that reduces vehicle trips
and encourages alternative transportation routes for pedestrian, equestrian and bicycle
use.
6. The preservation of open space, water quality and air quality to the greatest extent
possible.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-5
Alternative Projects Selected for Detailed Analysis C.
1. No Project Alternative
The No Project Alternative assumes that the build out of the General Plan would occur under
existing City and County General Plan land use designations. Within the City, that build out
would occur as planned in the currently approved General Plan. In the City’s Sphere of
Influence, build out would occur as anticipated in the Riverside County General Plan in the north
Sphere area; and as proposed in the Vista Santa Rosa Land Use Plan in the east Sphere area.
Within the City limits, this alternative is very similar to the Preferred Alternative. The most
significant differences with the Preferred Alternative occur in the Sphere of Influence. The
County’s General Plan and Vista Santa Rosa Land Use Plan propose primarily very low and low
density residential lands, with a community center and commercial core occurring along Airport
Boulevard, generally east of Van Buren. The single family residential land use designations
generally range from 1 unit per two acres to two units per acre. Medium and Medium High
Density Residential lands are proposed adjacent to the Community Center and commercial land
uses, and are estimated to build out in the range of 4 to 10 units per acre. Along Harrison Street,
between Airport Boulevard and Avenue 61 (extended), Business Park and Tourist Commercial
uses are proposed.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-7
Table V-4
No Project Alternative
Build Out Summary: City Limits Only
Land Use
Designation Developed Vacant Total
Existing
Units
Potential
Units
Total
Units
Very Low Density
Residential 209.5 227.6 437.1 341 341
Low Density
Residential 4,352.2 1,783.0 6,135.2 20,834 5,349 26,183
Medium Density
Residential 957.4 145.2 1,102.6 871 871
Medium High Density
Residential 315.2 205.3 520.5 2,655 1,848 4,503
High Density
Residential 90.4 2.6 93.0 31 31
Total 5,924.7 2,363.7 8,288.4 23,489 8,440 31,929
Existing SF
Potential
SF Total SF
Village Commercial 90.8 10.9 101.7 870,155 104,457 974,611
Regional Commercial 263.7 71.2 334.9 2,527,090 682,324 3,209,414
Community
Commercial 49.3 45.1 94.4 472,452 432,202 904,654
Neighborhood
Commercial 22.5 48.1 70.6 215,622 460,952 676,574
Tourist Commercial 210.4 150.4 360.8 2,016,305 1,441,313 3,457,619
Office Commercial 34.2 0.1 34.3 328,043 651 328,694
Commercial Park 38.4 20.3 58.6 367,691 194,296 561,987
Total 709.3 346.0 1,055.3 6,797,358 3,316,195 10,113,553
Major Community
Facilities 179.1 2.8 181.9
Parks and Recreation 611.3 87.2 698.5
Golf Course 3,891.1 1,000.3 4,891.4
Open Space 1,250.8 4,177.7 5,428.5
Water 511.2 124.0 635.2
Street Rights-of-Way 1,475.4 200.4 1,675.8
Grand Total 14,552.9 8,302.1 22,855.0
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-8
Table V-5
No Project Alternative
Build Out Summary: Sphere-of-Influence
Land Use
Designation
Develo
ped Vacant Total
Existing
Units Potential Units Total Units
Estate Density
Residential 136.9 1,160.3 1,297.2 580 580
Very Low Density
Residential 37.9 887.5 925.4 888 888
Low Density
Residential 235.8 4,003.5 4,239.3 801 6,005 6,806
Medium Density
Residential 101.0 200.4 301.3 751 751
Medium High Density
Residential 2.5 249.6 252.1 1,498 1,498
High Density
Residential 23.6 135.5 159.0 1,422 1,422
Total 537.6 6,636.9 7,174.4 801 11,144 11,945
Existing SF Potential SF Total SF
Commercial Retail 1.2 16.6 17.8 11,928 158,985 170,913
Commercial Tourist 0.0 119.9 119.9 - 1,149,107 1,149,107
Business Park 34.0 247.3 281.3 325,445 2,370,213 2,695,658
Community Center 7.5 112.12 119.6 71,617 1,074,468 1,146,086
Total 42.7 495.9 538.6 408,990.5 4,752,773.5 5,161,764.1
Public Facilities 28.2 40.2 68.4
Street Rights of Way 320.05 0 320.1
Total 348.2 40.2 388.4
Grand Total 928.5 7,173.0 8,101.5
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-9
Table V-6
No Project Alternative
Build Out Summary: Planning Area Total
Land Use Designation Developed Vacant Total
Existing
Units
Potential
Units Total Units
Very Low Density Residential 209.5 227.6 437.1 0 341 341
Low Density Residential 4,352.2 1,783.0 6,135.2 20,834 5,349 26,183
Medium Density Residential 957.4 145.2 1,102.6 0 871 871
Medium High Density
Residential 315.2 205.3 520.5 2,655 1,848 4,503
High Density Residential 90.4 2.6 93.0 0 31 31
Estate Density Residential 136.9 1,160.3 1,297.2 0 580 580
Very Low Density Residential 37.9 887.5 925.4 0 888 888
Low Density Residential 235.8 4,003.5 4,239.3 801 6,005 6,806
Medium Density Residential 101.0 200.4 301.3 0 751 751
Medium High Density
Residential 2.5 249.6 252.1 0 1,498 1,498
High Density Residential 23.6 135.5 159.0 0 1,422 1,422
Total 6,462.3 9,000.6 15,462.8 24,290 19,584 43,874
Existing
SF Potential SF Total SF
Village Commercial 90.8 10.9 101.7 870,155 104,457 974,611
Regional Commercial 263.7 71.2 334.9 2,527,090 682,324 3,209,414
Community Commercial 49.3 45.1 94.4 472,452 432,202 904,654
Neighborhood Commercial 22.5 48.1 70.6 215,622 460,952 676,574
Tourist Commercial 210.4 150.4 360.8 2,016,305 1,441,313 3,457,619
Office Commercial 34.2 0.1 34.3 328,043 651 328,694
Commercial Park 38.4 20.3 58.6 367,691 194,296 561,987
Commercial Retail 1.2 16.6 17.8 11,928 158,985 170,913
Commercial Tourist 0.0 119.9 119.9 0 1,149,107 1,149,107
Business Park 34.0 247.3 281.3 325,445 2,370,213 2,695,658
Community Center 7.5 112.1 119.6 71,617 1,074,468 1,146,086
Sub-Total 752.0 842.0 1,594.0 7,206,348.8 8,068,968.5 15,275,317.3
Major Community Facilities 179.1 2.8 181.9
Parks and Recreation 611.3 87.2 698.5
Golf Course 3,891.1 1,000.3 4,891.4
Open Space 1,250.8 4,177.7 5,428.5
Water 511.2 124.0 635.2
Public Facilities 28.2 40.2 68.4
Street Rights-of-Way 1,795.5 200.4 1,995.9
Sub-Total 8,267.1 5,632.6 13,899.7
Grand Total 15,481.4 15,475.2 30,956.5
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-10
2. Alternative 1
This Alternative would reduce residential land use intensity, and commercial acreage, and
represents a lower intensity option to the Preferred Alternative. Within the City limits, this
alternative would remove approximately 49 acres of Tourist Commercial land in the SilverRock
Resort, and replace it with Medium Density Residential. In addition, lands currently proposed for
Low Density Residential development in the southwestern corner of the City would develop at
Very Low Density Residential densities (2 units per acre).
Under this Alternative, almost all lands in the eastern Sphere area would be designated Very
Low Density Residential, with the exception of lands on the west side of Harrison Street, which
would remain Industrial and Commercial. Commercial lands on the east side of Monroe would
be significantly reduced.
Table V-7
Alternative 1
Build Out Summary: City Limits Only
Land Use Designation Developed Vacant Total
Existing
Units
Potential
Units Total Units
Very Low Density
Residential 0.0 339.2 339.2 509 509
Low Density
Residential 4,171.2 1,336.7 5,507.9 20,834 4,010 24,844
Medium/High Density
Residential 1,303.2 380.3 1,683.6 2,655 3,423 6,078
Total 5,474.4 2,056.2 7,530.6 23,489 7,942 31,431
Existing SF Potential SF Total SF
General Commercial 383.2 186.4 569.6 3,671,883 1,786,305 5,458,188
Tourist Commercial 189.1 108.6 297.7 1,812,074 1,040,786 2,852,860
Village Commercial 77.4 12.9 90.2 741,328 123,207 864,535
Total 649.6 307.9 957.5 6,225,285 2,950,298 9,175,583
Major Community
Facilities 238.0 160.0 398.0
Open Space - Natural 2,242.7 5,233.3 7,476.0
Open Space -
Recreation 4,272.0 287.5 4,559.5
Street Rights-of-Way 1,676.1 257.6 1,933.7
Grand Total 14,552.9 8,302.5 22,855.3
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-11
Table V-8
Alternative 1
Build Out Summary: Sphere-of-Influence
Land Use Designation Developed Vacant Total
Existing
Units
Potential
Units Total Units
Very Low Density
Residential 527.2 6,844.5 7,371.7 801 10,267 11,068
Low Density
Residential 27.5 71.9 99.4 0 216 216
Medium/High Density
Residential 0 5.5 5.5 0 50 50
Total 554.7 6,922.0 7,476.7 801 10,532 11,333
Existing SF Potential SF Total SF
General Commercial 25.6 185.6 211.2 245,298 1,778,761 2,024,059
Total 25.6 185.6 211.2 245,298 1,778,761 2,024,059
Existing SF Potential SF Total SF
Industrial/Lgt. Mfg. 0 63.8 63.8 - 611,393 611,393
Total 0.0 63.8 63.8 - 611,393 611,393
Major Community
Facilities 28.2 1.6 29.8
Street Rights-of-Way 319.9 0 319.9
Grand Total 928.4 7,173.0 8,101.4
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-12
Table V-9
Alternative 1
Build Out Summary: Planning Area Total
Land Use Designation Developed Vacant Total
Existing
Units
Potential
Units Total Units
Very Low Density
Residential 527.2 7,183.7 7,710.9 801 10,776 11,577
Low Density
Residential 4,198.7 1,408.5 5,607.3 20,834 4,226 25,060
Medium/High Density
Residential 1,303.2 385.9 1,689.1 2,655 3,473 6,128
Total 6,029.2 8,978.1 15,007.3 24,290 18,474 42,764
Existing SF Potential SF Total SF
General Commercial 408.8 372.0 780.8 3,917,181 3,565,066 7,482,247
Tourist Commercial 189.1 108.6 297.7 1,812,074 1,040,786 2,852,860
Village Commercial 77.4 12.9 90.2 741,328 123,207 864,535
Total 675.2 493.5 1,168.7 6,470,583 4,729,059 11,199,643
Existing SF Potential SF Total SF
Industrial/Lgt. Mfg. 0.0 63.8 63.8 - 611,393 611,393
Major Community
Facilities 266.2 161.6 427.7
Open Space - Natural 2,242.7 5,233.3 7,476.0
Open Space -
Recreation 4,272.0 287.5 4,559.5
Street Rights-of-Way 1,996.0 257.6 2,253.7
Grand Total 15,481.3 15,475.4 30,956.7
This alternative would result in a reduction of 24% of total residential units, when compared to
the Preferred Alternative. The potential Commercial and Industrial square footage would be
comparable, with a reduction of 10%. Under this Alternative, Open Space lands would be
somewhat reduced from the Preferred Alternative.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-14
3. Alternative 2
This Alternative was developed to analyze the potential for concentrated population centers near
commercial and public land uses, in order to reduce potential traffic and air quality impacts.
Under this Alternative, lands immediately south of Saint Francis Catholic Church would be
developed at Medium/High Density Residential intensities, as would all the lands in the north
Sphere of Influence. In addition, Medium/High Density lands would occur in the eastern Sphere,
adjacent to and west of the industrial and commercial lands along Harrison Street, and east of the
commercial lands on the east side of Monroe. Medium/High Density Residential lands would
also occur at the southeast corner of Airport Boulevard and Monroe. A 40 acre commercial
center would also be developed at Airport Boulevard and Van Buren, in the Vista Santa Rosa
area.
Table V-10
Alternative 2
Build Out Summary: City Limits Only
Land Use Designation Developed Vacant Total
Existing
Units
Potential
Units Total Units
Very Low Density
Residential 0.0 0.0 0.0 - 0
Low Density
Residential 4,171.2 1,636.9 5,808.1 20,834 4,911 25,745
Medium/High Density
Residential 1,284.0 389.3 1,673.3 2,655 3,503 6,158
Total 5,455.3 2,026.2 7,481.4 23,489 8,414 31,903
Existing SF
Potential
SF Total SF
General Commercial 383.2 186.4 569.6 3,671,883 1,786,305 5,458,188
Tourist Commercial 208.3 138.6 346.9 1,995,983 1,328,283 3,324,266
Village Commercial 77.4 12.9 90.2 741,328 123,207 864,535
Total 668.8 337.9 1,006.7 6,409,194 3,237,795 9,646,989
Major Community
Facilities 238.0 160.0 398.0
Open Space - Natural 2,242.7 5,233.3 7,476.0
Open Space -
Recreation 4,272.0 287.5 4,559.5
Street Rights-of-Way 1,676.1 257.6 1,933.7
Grand Total 14,552.9 8,302.5 22,855.3
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-15
Table V-11
Alternative 2
Build Out Summary: Sphere-of-Influence
Land Use Designation Developed Vacant Total
Existing
Units
Potential
Units Total Units
Very Low Density
Residential 0.0 0.0 0.0 0 - 801
Low Density
Residential 483.3 6,161.9 6,645.2 801 18,486 19,287
Medium/High Density
Residential 67.7 652.0 719.7 0 5,868 5,868
Total 550.9 6,813.9 7,364.8 801 24,354 25,956
Existing SF
Potential
SF Total SF
General Commercial 29.4 293.7 323.0 281,461 2,814,376 3,095,837
Total 29.4 293.7 323.0 281,461 2,814,376 3,095,837
Existing SF
Potential
SF Total SF
Industrial/Lgt. Mfg. 0 63.8 63.8 - 611,393 611,393
Total 0.0 63.8 63.8 - 611,393 611,393
Major Community
Facilities 28.2 1.6 29.8
Street Rights-of-Way 319.9 0 319.9
Grand Total 928.4 7,173.0 8,101.4
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-16
Table V-12
Alternative 2
Build Out Summary: Planning Area Total
Land Use Designation Developed Vacant Total
Existing
Units
Potential
Units Total Units
Very Low Density
Residential 0.0 0.0 0.0 801 0 801
Low Density
Residential 4,654.5 7,798.8 12,453.3 20,834 23,396 44,230
Medium/High Density
Residential 1,351.7 1,041.3 2,393.0 2,655 9,371 12,026
Total 6,006.2 8,840.1 14,846.3 24,290 32,768 57,058
Existing SF
Potential
SF Total SF
General Commercial 412.5 480.1 892.6 3,953,343 4,600,681 8,554,024
Tourist Commercial 208.3 138.6 346.9 1,995,983 1,328,283 3,324,266
Village Commercial 77.4 12.9 90.2 741,328 123,207 864,535
Total 698.2 631.5 1,329.7 6,690,654 6,052,171 12,742,826
Industrial/Lgt. Mfg. 0.0 63.8 63.8 - 611,393 611,393
Major Community
Facilities 266.2 161.6 427.7
Open Space - Natural 2,242.7 5,233.3 7,476.0
Open Space -
Recreation 4,272.0 287.5 4,559.5
Street Rights-of-Way 1,996.0 257.6 2,253.7
Grand Total 15,481.3 15,475.4 30,956.7
Under this Alternative, residential units would increase by 7.5% over the Preferred Alternative.
Commercial and industrial lands would be generally consistent with the Preferred Alternative,
representing an increase of about 378,000 square feet. Open Space land use designations would
be consistent with the Preferred Alternative.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-18
Alternative Projects Analysis D.
A. Aesthetics
The land within the City limits is mostly built out, and will experience redevelopment and infill
development on vacant or underutilized parcels under all alternatives. The Sphere of Influence
areas will see more significant changes over the next twenty five years, and convert from an
agricultural and rural community to a more urban setting. The discussion below addresses
aesthetic impacts according to each of the three project alternatives, including a “No Project
Alternative”, “Alternative 1”, and a “Alternative 2.”
No Project Alternative
The No Project Alternative would result in continued land uses proposed under the existing La
Quinta General Plan, for areas within the City limits, and the existing Riverside General Plan and
Vista Santa Rosa Community Land Use Concept Plan for areas within the Sphere of Influence.
Build out of the No Project Alternative would allow for approximately 326 more residential
units, and approximately 481,479 additional square feet of commercial space within the City
Limits compared to the Preferred Alternative. The increase in units and square footage would
occur over the entire City, and would not significantly change the character or building type of
future development. More intense development will marginally increase light and glare impacts,
as additional commercial will generate more lighting needed for parking lots and security
purposes. The No Project Alternative will, therefore, likely cause slightly higher impacts on
aesthetic resources in the City Limits than the Preferred Alternative.
Within the Sphere of Influence, the No Project Alternative would result in approximately 9,555
fewer residential units, and approximately 2,429,207 additional square feet of commercial space
relative to the Preferred Alternative. The No Project Alternative provides for a wider variety of
residential uses than the Preferred Alternative, ranging from Estate Density Residential to High
Density Residential. Much of the Sphere of Influence, under the No Project Alternative, is
designated as Estate and Very Low Density Residential. Unlike the Preferred Alternative, the No
Project Alternative does not provide industrial uses. In regards to scenic vistas, the reduced
amount of residential units and lack of industrial uses in the No Project Alternative may
beneficially impact scenic vistas, insofar as a lower intensity of residential units will leave larger
areas of viewshed. The higher amount of commercial square footage allowed under the No
Project Alternative, however, could create greater impact on scenic vistas. Commercial structures
tend to be higher and more bulky than residential structures, and such buildings may affect views
of the surrounding environment.
In terms of visual character, the Sphere of Influence is currently rural and has an agrarian
character. The No Project Alternative does provide lower intensity and density residential than
the Preferred Alternative, but the higher amount of commercial uses may offset the difference
and create a more urban environment.
In terms of light and glare, the lower density residential designations may help reduce impacts on
light and glare. These impacts, however, may be offset by the higher amounts of commercial
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-19
square footage. As described above, commercial uses increase light and glare associated with
parking lots and security.
In regards to scenic resources, such as trees, rock outcroppings and historic buildings within a
state scenic highway, the No Project Alternative will have the same effect as the Preferred
Alternative. Currently, there are no state scenic highways in either the City or the Sphere.
Overall, the No Project Alternative would have similar impacts, or slightly higher impacts, on
aesthetic resources than the Preferred Alternative.
Alternative 1
Alternative 1 allows for the least amount of development to occur throughout the entire General
Plan Update Planning Area. In terms of residential uses, Alternative 1 provides 172 fewer
residential units in the City limits, and 10,167 fewer units in the Sphere of Influence than the
Preferred Alternative. Alternative 1 also reduces commercial uses by 456,491 square feet in the
City, and 708,498 square feet in the Sphere of Influence. Industrial land uses are similar between
the two alternatives.
As discussed above, impacts on scenic vistas are related to number of buildings and structures
that impede views of mountains, desert, and surrounding landscape. The Alternative 1 reduces
the amount of buildings, and therefore will have less impact on the scenic vista than the
Preferred Alternative. Visual character will also be preserved under Alternative 1, especially in
the Sphere of Influence. The Alternative 1 provides for very low density residential throughout
the Sphere of Influence, instead of low density residential proposed under the Preferred
Alternative. This lower density residential will help protect the rural visual character that
currently exists within the Sphere of Influence. Light and glare impacts will also be reduced
under Alternative 1, specifically due to reduced amount of commercial uses proposed under
Alternative 1.
In regards to scenic resources, such as trees, rock outcroppings, and historic buildings within a
state scenic highway, the Less Intense Project Alternative will have a similar effect as the
Preferred Alternative. Currently, there are no state scenic highways that run through La Quinta.
Overall, Alternative 1 creates the least amount of impacts on aesthetic resources over all other
Alternatives.
Alternative 2
Alternative 2 would result in more intense development throughout the General Plan Update
Planning Area, especially throughout the Sphere of Influence. Build out of Alternative 2 would
allow for approximately 300 more residential units in the City Limits than what is proposed
under the Preferred Alternative, and increase commercial uses by 14,915 square feet in the City.
In terms of its effect on scenic vistas, Alternative 2 will have a similar, or slightly increased,
impact than the Preferred Alternative. Residential uses tend to be smaller scale buildings, so the
increased residential will most likely have a limited effect on views of surrounding mountains
and desert. Likewise, the increased amount of commercial square footage is expected to have
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-20
only limited impacts on nearby viewsheds. In terms of the visual character, La Quinta is
predominantly a residential suburban community, and visual character is characterized by small
scale residential buildings intermixed with larger commercial centers. The higher amounts of
residential and commercial uses proposed under Alternative 2 will most likely cause similar, or
slightly higher, impacts on the visual character compared to the Preferred Alternative. Impacts
from light and glare will also be similar, or slightly higher under Alternative 2. The increased
amount of commercial square footage may create a slight increase in glare and lighting
associated with buildings, parking lots, and security lighting.
Alternative 2 would have the greatest impact on aesthetics within the Sphere of Influence, but
these impacts will not be significantly increased over the Preferred Alternative. This Alternative
allows for 3,655 additional residential units and 363,280 additional square feet of commercial
uses over the Preferred Alternative. Alternative 2 allows for medium to high density residential
in the Sphere of Influence, which is not allowed under the Preferred Alternative. This increased
amount of residential and commercial development will affect the scenic vista by creating more
structures and buildings that may impede views of local mountains, desert, and rural nature of
the area.
The visual character will also be impacted by Alternative 2. The Sphere of Influence is currently
rural, and more intense and higher density development will likely change the area into an urban
environment. In regards to light and glare impacts, Alternative 2 would result in more lighting
and glare than the Preferred Alternative. The greater amount of residential units and commercial
square footage in the Sphere of Influence would result in more lighting from parking lots,
commercial buildings, and residential buildings.
In regards to scenic resources, such as trees, rock outcroppings, and historic buildings within a
state scenic highway, the More Intense Project Alternative will have a similar effect as the
Preferred Alternative throughout both the City Limit and Sphere of Influence. Currently, there
are no state scenic highways in either the City or the Sphere.
Overall, Alternative 2 results in a somewhat more significant impact on aesthetic resources than
the Preferred Alternative.
B. Agricultural Resources
The Riverside County Important Farmland Map of 2008 highlights important agricultural lands
throughout the region. These important agricultural lands are found throughout the General Plan
Update Planning Area, and are most prevalent throughout the Sphere of Influence. The land uses
proposed by all four Alternatives will allow urbanization to continue on important farmlands.
No Project Alternative
The No Project Alternative would result in new development regulated by the 2002 General Plan
for areas within City Limits, the Riverside County General Plan in the north Sphere of Influence
area, and the Vista Santa Rosa Land Use Plan in the eastern Sphere of Influence area. In the City,
neither the Preferred Alternative nor the No Project Alternative provide agricultural land use
designations, but do allow small farming and equestrian related uses in the Very Low Density
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-21
Residential zone. No new farming would be expected in the City under this alternative. Impacts
on agricultural resources will be similar to those under the Preferred Alternative.
In the northern Sphere of Influence, the No Project Alternative would designate the area Medium
Density Residential as opposed to the Low Density Residential designation proposed by the
Preferred Alternative. Both land uses promote residential development. Currently, the northern
Sphere of Influence is used for small nurseries, residential units, and vacant land. This area is
surrounded by residential subdivisions, however, and is likely to develop in a similar fashion.
Impacts related to agricultural conversion, therefore, would be similar to those created by the
Preferred Alternative.
Within the eastern Sphere of Influence, land use designations proposed by the Vista Santa Rosa
Community Plan include estate, very low and low density residential lands, with a community
center and commercial uses along Airport Boulevard. This area has the potential to experience
the greatest impact on agricultural resources. The eastern Sphere of Influence has 7,391 acres of
land considered prime farmland, as well as 582 acres currently under Williamson Act contracts.
The estate and very low density residential land uses would allow larger lots for equestrian and
small agricultural production. The Vista Santa Rosa Community Plan, however, does not allow
stand-alone agriculture. The No Project Alternative, therefore, would have slightly less impact
on agricultural resources in the eastern Sphere of Influence than the Preferred Alternative.
Overall, the agricultural resource impacts are slightly less under the No Project Alternative than
the Preferred Alternative, mainly due to limited agricultural activities allowed in the eastern
Sphere of Influence under the Vista Santa Rosa Community Plan.
Less Intense Project Alternative
The Less Intense Project Alternative would reduce residential land use intensity, and commercial
acreage throughout the General Plan Update Planning Area. Within the City, impacts on
agricultural resources under the Less Intense Project Alternative would be the same as those
under the Preferred Alternative.
In the northern Sphere of Influence, Alternative 1 provides the same land use designation as the
Preferred Alternative. Therefore, impacts on agricultural resources under Alternative 1 are
equivalent to the Preferred Alternative in the northern Sphere of Influence.
In the eastern Sphere of Influence, Alternative 1 designates all residential lands as Very Low
Density Residential rather than the Low Density Residential designation provided under the
Preferred Alternative. This lower density residential land use designation may potentially allow
small agriculture and equestrian uses on larger lots conducive for small farming operations.
Alternative 1 may potentially allow agricultural production on lands considered important for
agriculture resources, and protect parcels that are currently under Williamson Act. Therefore, in
terms of agricultural resources, Alternative 1 has slightly lower impacts on agricultural resources
than the Preferred Alternative.
Overall, impacts on agriculture resources under Alternative 1 are slightly less than those under
the Preferred Alternative.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-22
Alternative 2
Alternative 2 allows for more intensive land uses throughout the General Plan Update Planning
Area. Within the City, impacts on agricultural resources under the More Intense Project
Alternative would be similar to those under the Preferred Alternative.
In the northern Sphere of Influence, Alternative 2 allows for higher intensity residential uses than
provided for under the Preferred Alternative, however both alternatives would prohibit
agriculture uses.
In the eastern Sphere of Influence, Alternative 2 designates some areas as higher intensity
residential and more commercial land is designated, but it is otherwise very similar to the
Preferred Alternative. Neither alternative allow agriculture.
Overall, impacts on agriculture resources under Alternative 2 are equivalent to those under the
Preferred Alternative.
C. Air Quality
A comprehensive discussion on the potential air quality and GHG impacts for the Preferred
Alternative can be found in Section III of this EIR. Also refer to the Air Quality and GHG
Report included in Appendix B of this EIR for detailed demand projections and emission tables
for each of the Alternatives. The discussion below compares the Preferred Alternative to the
other proposed alternatives, and assesses the relative level of impact to air quality.
No Project Alternative
The No Project Alternative would result in build out within City limits pursuant to the 2002
General Plan. Under this Alternative the Sphere of Influence would build out as directed by the
County’s Vista Santa Rosa Land Use Concept Plan and the County’s General Plan. A discussion
of the air quality impacts associated with this level of development and operation are
summarized below. Detailed demand and emission projections are included in the Air Quality
and GHG Report.
Construction impacts for the No Project Alternative are comparable to the construction impacts
projected for the Preferred Project Alternative. This is due to the fact that the No Project
Alternative results in an intensification of development for commercial land uses, but a reduction
in the total number of dwelling units. Although the total acreages of development for the
Preferred Alternative and the No Project Alternative are the same, the No Project Alternative
will result in approximately 9,228 fewer dwelling units, and an increase in the commercial
square footage of about 2.9 million square feet. Therefore, it is assumed that construction
activities will result in air quality emissions that are comparable to the emission projections for
construction as set forth under the Preferred Alternative discussion, which is expected to exceed
established daily thresholds for NOx and ROG.
Under the No Project Alternative, natural gas and electricity demands will be higher in the City
limits and lower in the Sphere of Influence relative to the Preferred Alternative. Energy and
natural gas demands within City limits will be slightly higher under the No Project Alternative
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-23
compared to the Preferred Alternative. Under the No Project Alternative, within City limits
annual demands are projected be 1,467,168,248 cubic feet for natural gas and 1,121,724,203
kilowatt hours for electricity. For the Sphere of Influence, the No Project Alternative is projected
to generate an annual natural gas demand of 622,238,575 cubic feet and an electricity demand of
499,422,871 kwh, which are slightly less than demands for the Preferred Alternative. For the No
Project Alternative energy and natural gas demands over the entire Planning Area are projected
to be slightly less than demands projected for the Preferred Alternative.
The summary table below shows the total emission projections for the No Project Alternative
from electricity, natural gas, area sources and moving sources for City limits, the Sphere of
Influence and the overall La Quinta Planning Area.
As projected, air quality emissions for all criteria pollutants (CO, NOx, SOx, Particulates and
ROG’s) are projected to exceed established SCAQMD thresholds at operation of the No Project
Alternative. Compared to the Preferred Alternative, the No Project Alternative is projected to
result in comparable quantities of criteria pollutants from electricity, natural gas, area sources
and moving sources.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-24
Table V-13
Cumulative Daily Emissions No Project Alternative
(Lbs./day)
Stationary Source Emissions
Moving
Sources
Total
Emissions
Threshold
Criteria*
Electricity
Natural
Gas
Area
Sources
Vehicles
Total
Lbs./Day
Lbs./Day
City Limits
CO 614.64 225.67 7,597.77 8,396 16,834.08 550
NOx 3,534.20 386.70 423.75 779 5,123.15 100
SOx 368.79 0.004 19.55 22 410.40 150
PM10 122.93 0.72 1,078.36 3,790 4,992.01 150
PM2.5 N/a N/a 1,038.90 743 1,781.90 55
ROGs 30.73 29.18 4,427.08 947 5,433.50 75
Sphere of Influence
CO 273.66 101.31 2,795.99 3,691 6,861.96 550
NOx 1,573.52 164.76 138.74 346 2,222.52 100
SOx 164.19 0.002 7.30 10 181.49 150
PM10 54.73 0.31 403.15 1,684 2,142.19 150
PM2.5 N/a N/a 388.42 330 718.42 55
ROGs 13.68 12.38 1,653.17 414 2,092.73 75
Planning Area
CO 888.30 326.98 10,393.76 12,087.00 23,696.04 550
NOx 5,107.72 551.46 562.49 1,124.00 7,345.67 100
SOx 532.98 0.01 26.84 32.06 591.89 150
PM10 177.66 1.03 1,481.50 5,474.00 7,134.19 150
PM2.5 N/a N/a 1,427.32 1,073.00 2,500.32 55
ROGs 44.41 41.56 6,080.26 1,360.00 7,526.23 75
Source: Air Quality and GHG Report, prepared by Terra Nova, June 2012.
All reasonable and feasible mitigation measures as set forth under the Preferred Alternative
discussion would be applicable to the No Project Alternative.
Greenhouse Gas Emissions
The No Project Alternative will also result in the emission of GHG’s through the combustion of
fossil fuels during operation of vehicles, the generation of electricity at power plants, combustion
of natural gas, and the transportation of water. GHG emission projections for the No Project
Alternative are set forth in the table below and are comparable to the Preferred Alternative.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-25
Table V-14
GHG Emissions for the No Project Alternative
(million metric tons)
Electricity
Natural
Gas
Moving
Sources
Water
Transport Total
City Limits 0.492 0.080 0.426 0.0108 1.010
Sphere of Influence 0.219 0.034 0.189 0.004 0.446
Planning Area 0.711 0.114 0.615 0.015 1.456
See Appendix D of the Air Quality and GHG Report for detailed tables.
As with the Preferred Alternative, implementation of the Greenhouse Gas Reduction Plan under
the No Project Alternative would be sufficient mitigation to reduce potential impacts from
greenhouse gases to levels below significance. In the event that lands within the Sphere of
Influence were annexed into La Quinta, compliance with the GHG Reduction Plan would be
required. Under County jurisdiction lands within the Sphere of Influence have the potential to
result in significant impacts from the emission of greenhouse gases.
Alternative 1
Construction impacts for Alternative 1 are expected to be slightly less than construction impacts
projected for the Preferred Alternative. This is because Alternative 1 consists of less dense land
use development compared to the Preferred Alternative. Although the total acreages of vacant
land to be developed are the same under the two Alternatives, Alternative 1 will result in
approximately 10,399 fewer dwelling units, and a reduction of 1,164,989 square feet of
commercial space compared to the Preferred Alternative. Construction activities under
Alternative 1 will result in air quality emissions that are slightly reduced compared to the
emission projections for construction as set forth under the Preferred Alternative. Nonetheless,
established daily thresholds for NOx, ROG, and PM10 are expected to be exceeded from
construction of Alternative 1.
Under this Alternative, natural gas and electricity demands will be reduced compared to the
Preferred Alternative. Within City limits, annual demands for Alternative 1 are projected to be
1,402,741,087 cubic feet for natural gas and 1,059,057,498 kilowatt hours for electricity. For the
Sphere of Influence, Alternative 1 is projected to generate an annual natural gas demand of
469,980,612 cubic feet and an electricity demand of 342,918,007 kwh, which are less than
demand projections for the Preferred Alternative. Throughout the Planning Area, natural gas
demands are projected to be 1,872,721,699 cubic feet per year under Alternative 1, which is
substantially lower than the 2,238,326,502 cubic feet projected for the Preferred Alternative.
Similarly, the electricity demand for the entire Planning Area, under Alternative 1, is projected to
be 1,401,975,505 kilowatt hours, which is a 243,170,095 kilowatt hour decrease from the
1,645,145,600 kilowatt hour demand projected for the Preferred Alternative.
The summary table below shows the total emission projections for Alternative 1 from electricity,
natural gas, area sources and moving sources for City limits, the Sphere of Influence and the
overall La Quinta Planning Area.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-26
Air quality emissions for all criteria pollutants (CO, NOx, SOx, Particulates and ROG’s) are
projected to exceed established SCAQMD thresholds at build out of Alternative 1. Compared to
the Preferred Alternative, the Less Intense Project Alternative is projected to result in reduced
emission of criteria pollutants from electricity, natural gas, area sources and moving sources.
Nonetheless, all thresholds criteria will be exceeded and impacts to air quality have the potential
to be significant.
All reasonable and feasible mitigation measures as set forth under the Preferred Alternative
discussion would be applied to Alternative 1.
Greenhouse Gas Emissions
Alternative 1 will result in the emission of greenhouse gases through the combustion of fossil
fuels during operation of vehicles, the generation of electricity at power plants, combustion of
Table V-15
Cumulative Daily Emissions Alternative 1
(Lbs./day)
Stationary Source
Emissions
Moving
Emissions
Total
Emissions
Threshold
Criteria*
Electricity
Natural
Gas
Area
Sources
Vehicles
Total
Lbs./Day
Lbs./Day
City Limits
CO 580.31
212.59
7,463.15 8,308 16,564.05 550
NOx 3,336.77
369.28
415.16 773 4,893.71 100
SOx 348.18
0.004
19.24 22 389.42 150
PM10 116.06
0.69
1,061.42 3,835 5,013.17 150
PM2.5 N/a
N/a
1,022.56 751 1,773.56 55
ROGs 29.02
27.90
4,348.82 931 5,336.24 75
Sphere of Influence
CO 187.90 68.41 2,750.01 3,430 6,435.83 550
NOx 1,080.43 123.34 169.90 324 1,697.17 100
SOx 112.74 0.001 6.96 10 129.71 150
PM10 37.58 0.23 383.08 1,717 2,137.90 150
PM2.5 N/a
N/a
369.05 335 704.05 55
ROGs 9.40 9.35 1,587.75 361 1,967.49 75
Planning Area
CO 768.21 281.00 10,213.16 11,737.50 22,999.87 550
NOx 4,417.19 492.62 585.06 1,096.00 6,590.88 100
SOx 460.92 0.01 26.20 32.00 519.13 150
PM10 153.64 0.92 1,444.50 5,552.00 7,151.07 150
PM2.5 N/a
N/a
1,391.60 1,086.00 2,477.60 55
ROGs 38.41 37.25 5,936.57 1,291.50 7,303.73 75
Source: Air Quality and GHG Report, prepared by Terra Nova, June 2012.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-27
natural gas, and the transportation of water. GHG emission projections for Alternative 1 are set
forth in the table below and are slightly reduced compared to the Preferred Alternative.
Table V-16
GHG Emissions for Alternative 1
(million metric tons)
Electricity
Natural
Gas
Moving
Sources
Water
Transport Total
City Limits 0.465 0.077 0.430 0.011 0.982
Sphere of Influence 0.150 0.026 0.190 0.004 0.370
Planning Area 0.615 0.102 0.620 0.015 1.352
Source: Air Quality and GHG Report, prepared by Terra Nova, June 2012.
As with the Preferred Alternative, implementation of the Greenhouse Gas Reduction Plan under
Alternative 1 would be sufficient mitigation to reduce potential impacts from greenhouse gases
to levels below significance. In the event that lands within the Sphere of Influence were annexed
into La Quinta, compliance with the GHG Reduction Plan would be required. Under County
jurisdiction lands within the Sphere of Influence have the potential to result in significant
impacts from the emission of greenhouse gases.
Alternative 2
This Alternative is expected to result in the emission of slightly more pollutants compared to
emission projections for the Preferred Alternative. This is because Alternative 2 consists of more
dense land use development compared to the Preferred Alternative. Although the total acreages
of vacant land to be developed are the same under the two Alternatives, Alternative 2 will result
in 3,955 more residential units, and an additional 378,195 square feet of commercial compared to
the Preferred Alternative. Construction activities for Alternative 2 will result in emissions that
are slightly elevated in comparison to the emission projections for construction set forth under
the Preferred Alternative. Established daily thresholds for NOx, ROG, PM10, and PM2.5 are
expected to be exceeded from construction of land uses proposed in Alternative 2.
Under Alternative 2 natural gas and electricity demands will be increased compared to the
Preferred Alternative. Annual demands for Alternative 2 within City limits are projected to be
1,441,566,735 cubic feet for natural gas and 1,094,274,318 kilowatt hours for electricity; and for
the Sphere of Influence natural gas demands are projected to be 929,123,261 cubic feet and
electricity demands are projected to be 637,122,426 kwh. Throughout the Planning Area natural
gas demands are projected to be 2,370,689,995 cubic feet per year under Alternative 2, which is
132,363,493 cubic feet more than the 2,238,326,502 cubic feet projected for the Preferred
Alternative. Similarly, the electricity demand for the entire Planning Area under Alternative 2 is
projected to be 1,731,396,744 kilowatt hours, which is a 86,251,144 kilowatt hour increase
relative to the 1,645,145,600 kilowatt hour demand projected for the Preferred Alternative.
Air quality emissions for all criteria pollutants (CO, NOx, SOx, Particulates and ROG’s) are
projected to exceed established SCAQMD thresholds at operation of Alternative 2. Compared to
the Preferred Alternative, Alternative 2 is projected to result in a similar level of emissions
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-28
within the City limits, and increased emissions of criteria pollutants from electricity, natural gas,
area sources and moving sources within the Sphere of Influence. As seen in the Table below, all
threshold criteria will be exceeded and impacts to air quality have the potential to be significant
under Alternative 2.
Table V-17
Cumulative Daily Emissions Alternative 2
(Lbs./day)
Stationary Source
Emissions
Moving
Sources
Total
Emissions
Threshold
Criteria*
Electricity
Natural
Gas
Area
Sources
Vehicles
Total
Lbs./Day
Lbs./Day
City Limits
CO 599.60 219.87 7,574.10 8,573 16,966.50 550
NOx 3,447.71 379.69 419.67 798 5,044.94 100
SOx 359.76 0.004 19.52 23 402.34 150
PM10 119.92 0.71 1,077.36 3,957 5,154.99 150
PM2.5 N/a N/a 1,037.92 775 1,812.97 55
ROGs 29.98 28.67 4,416.03 948 5,423.05 75
Sphere of Influence
CO 349.11 125.61 5,962.74 5,418 11,855.21 550
NOx 2,007.39 242.53 342.07 502 3,093.91 100
SOx 209.47 0.003 15.38 15 239.92 150
PM10 69.82 0.46 849.35 2,588 3,507.29 150
PM2.5 N/a N/a 818.16 506 1,324.24 55
ROGs 17.46 18.48 3,453.99 583 4,072.87 75
Planning
Area
CO 948.71 345.48 13,536.84 13,990.68 28,821.70 550
NOx 5,455.10 622.22 761.74 1,299.79 8,138.85 100
SOx 569.23 0.01 34.90 38.13 642.26 150
PM10 189.74 1.17 1,926.71 6,544.66 8,662.28 150
PM2.5 N/a N/a 1,856.08 1,281.13 3,137.21 55
ROGs 47.44 47.15 7,870.02 1,531.32 9,495.92 75
Source: Air Quality and GHG Report, prepared by Terra Nova, June 2012.
As with the Preferred Alternative, all reasonable and feasible mitigation measures will be applied
to Alternative 2 in order to limit emissions from operation.
Greenhouse Gas Emissions
Alternative 2 will result in the emission of greenhouse gases through the combustion of fossil
fuels during operation of vehicles, the generation of electricity at power plants, combustion of
natural gas, and the transportation of water. GHG emission projections for Alternative 2 are set
forth in the table below and are slightly greater than GHG emission projections for the Preferred
Alternative.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-29
Table V-18
GHG Emissions for Alternative 2
(million metric tons)
Electricity
Natural
Gas
Moving
Sources
Water
Transport Total
City Limits 0.480 0.079 0.443 0.011 1.013
Sphere of Influence 0.280 0.051 0.289 0.009 0.628
Planning Area 0.760 0.130 0.732 0.019 1.641
Source: Air Quality and GHG Report, prepared by Terra Nova, June 2012.
As with the Preferred Alternative implementation of the Greenhouse Gas Reduction Plan under
this Alternative would be sufficient mitigation to reduce potential impacts from greenhouse gases
to levels below significance. In the event that lands within the Sphere of Influence were annexed
into La Quinta, compliance with the GHG Reduction Plan would be required. Under County
jurisdiction lands within the Sphere of Influence have the potential to result in significant
impacts from the emission of greenhouse gases.
D. Biological Resources
The potential impacts to biological resources are primarily associated with land conversion and
proposed development that results in the loss of habitat. Although the four Alternatives propose
various amounts of growth and types of development, all Alternatives result in the development
of approximately 30,957 acres throughout the Planning Area. Development and urbanization of
these lands has the potential to result in impacts to biological resources, such as loss or
degradation of habitat, incidental take of listed species, and impacts to common and sensitive
species. The following discussion analyzes potential impacts to biological resources that may
result from implementation of each of the project alternatives.
As noted in Section III-D impacts to biological resources are addressed in the Coachella Valley
Multiple-Species Habitat Conservation Plan (MSHCP), which provides mitigation for incidental
take resulting from individual development projects. Mitigation includes payment of per-acre
mitigation fees for all new development within the MSHCP planning area, which will apply
regardless of the alternative implemented.
All four alternatives, including the No Project Alternative, Alternative 2, Alternative 1, and the
Preferred Alternative, provide land use designations that allow for continued urbanization
throughout the Planning Area. Despite the fact that some alternatives propose more intense land
uses over others, each of the four alternatives will facilitate development on land that may
contain sensitive biological resources. Mitigation measures, comparable to those listed in Section
III-D will be required for all new development in order to protect biological resources. These
mitigation measures, along with State and Federal regulations pertaining to biological resources,
as well as the CV MSHCP are expected to reduce impacts to biological resources to less than
significant levels for all Alternatives.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-30
E. Cultural Resources
The La Quinta General Plan Update Planning Area is rich in cultural resources. Archaeological
discoveries have uncovered remnants from the prehistoric Cahuilla tribe. Future development
and construction activities will continue to reveal buried cultural resources.
Impacts on cultural resources, including historical, archaeological, and paleontological resources,
within the General Plan Update Planning Area, will be caused by new development on lands
considered culturally sensitive. Section III-E of this EIR describes lands located within the
Planning Area that are considered highly sensitive in terms of paleontological sensitivity. These
high sensitivity areas include the entire Sphere of Influence, and select areas within the City
Limit. It should be noted that portions of the City and eastern Sphere of Influence remain
unsurveyed. These areas may contain historic and archaeological resources, and new
development projects in these areas will require cultural surveys.
All four alternatives, including the No Project Alternative, Alternative 1, Alternative 2, and the
Preferred Alternative, provide land use designations that allow for continued urbanization
throughout the Planning Area. Despite the fact that some alternatives propose more intense land
uses over others, each of the four alternatives will facilitate development on culturally sensitive
lands. There is not one alternative that provides open space or conservation areas over lands
considered culturally significant. Impacts to cultural resources, therefore, are expected to be
comparable under each alternative.
Mitigation measures, such those in Section III-E., will be required for all new development in
order to protect cultural resources. These mitigation measures, along with State and Federal
regulations pertaining to cultural resources, are expected to create less than significant impacts
on cultural resources.
F. Geology & Soils
The potential impacts of geology and soils are primarily associated with the region’s seismic
activity, which is relative to the number of people impacted by these risks. The four Alternatives
propose various amounts of growth and types of development, which increase or decrease
impacts related to seismic hazards. The following discussion analyzes potential impacts of
geology and soils that may result from implementation of each of the project alternatives.
No Project Alternative
Build out under the No Project Alternative would result in an increased number of residential
units and commercial square footage relative to the Preferred Alternative within the City Limits.
The No Project Alternative will expose a greater number of people, dwelling units, and buildings
to seismic events and related impacts such as liquefaction, and seismically induced slope
instability and inundation compared to the Preferred Alternative. Similarly, a greater number of
people and structures will be exposed to impacts associated with soil conditions, including
settlement and ground subsidence, rockfall from hillsides, soils expansion, and aerially deposited
dust and particulate matter.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-31
For the Sphere of Influence, the No Project Alternative reduces the amount of residential units by
almost half compared to the Preferred Alternative. This significantly reduces the number of
residents susceptible to seismic hazards and exposure to impacts from soil conditions. As such,
the number of people requiring assistance during emergencies and evacuations will be
substantially reduced under the No Project Alternative. However, the No Project Alternative will
result in an additional 2.43 million square feet of commercial development within the Sphere
over what is proposed for the Preferred Alternative. As such, the No Project Alternative has the
potential to result in greater impacts to commercial development in the Sphere due to seismic
activity.
The overall Planning Area under the No Project Alternative is similar to the Preferred
Alternative in regards to impacts associated with geology and soils. However, 23,348 fewer
residents, 9,229 fewer dwelling units, and an additional 2.91 million square feet of commercial
development have the potential to be impacted under the No Project Alternative compared to the
Preferred Alternative.
Alternative 1
Build out of Alternative 1 will result in a slight decrease in the number of residential units (172)
and commercial square footage (456,491) relative to the Preferred Alternative, within the City
Limits. Alternative 1 will expose slightly fewer people, dwelling units, and buildings to seismic
events and related impacts such as liquefaction, and seismically induced slope instability and
inundation compared to the Preferred Alternative. Similarly, slightly fewer people and structures
will be exposed to impacts associated with soil conditions, including settlement and ground
subsidence, rockfall from hillsides, soils expansion, and aerially deposited dust and particulate
matter under Alternative 1 relative to the Preferred Alternative.
For the Sphere of Influence, Alternative 1 reduces the number of residential units by almost half
compared to the Preferred Alternative. This significantly reduces the number of residents
susceptible to seismic hazards and exposure to impacts from soil conditions. As such, the number
of people requiring assistance during an emergency or evacuation will be reduced by 25,724
people under Alternative 1. Similarly, Alternative 1 will result in a decrease of approximately
708,498 square feet of commercial development within the Sphere over what is proposed for the
Preferred Alternative. As such, Alternative 1 will result in fewer impacts to commercial
development in the Sphere due to seismic activity relative to the Preferred Alternative.
The overall Planning Area under Alternative 1 is similar to the Preferred Alternative in regards
to impacts associated with geology and soils. However, 26,159 fewer residents, 10,339 fewer
dwelling units, and 1.16 million square feet less of commercial development have the potential to
be impacted under Alternative 1 compared to the Preferred Alternative.
Alternative 2
Build out of Alternative 2 will result in a slight increase in the number of residential units (300)
and a slight increase in the commercial square footage (14,915) relative to the Preferred
Alternative, within the City Limits. Alternative 2 will expose slightly more people, dwelling
units, and commercial square footage to seismic events and related impacts such as liquefaction,
and seismically induced slope instability and inundation compared to the Preferred Alternative.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-32
Similarly, slightly more people will be exposed to impacts associated with soil conditions,
including settlement and ground subsidence, rockfall from hillsides, soils expansion, and aerially
deposited dust and particulate matter under Alternative 2 relative to the Preferred Alternative.
For the Sphere of Influence, Alternative 2 increases the number of residential units by 3,655
units compared to the Preferred Alternative, which increases the number of residents susceptible
to seismic hazards and exposure to impacts from soil conditions. As such, the number of people
requiring assistance during an emergency or evacuation will increase by 9,246 people under
Alternative 2. Similarly, Alternative 2 will result in an increase of approximately 363,280 square
feet of commercial development within the Sphere over what is proposed for the Preferred
Alternative. As such, Alternative 2 has the potential to result in slightly greater impacts to
commercial development in the Sphere due to seismic activity relative to the Preferred
Alternative.
The overall Planning Area under Alternative 2 is similar to the Preferred Alternative in regards
to impacts associated with geology and soils. However, an additional 10,005 residents, 3,955
dwelling units, and 378,195 square feet of commercial development have the potential to be
impacted under Alternative 2 compared to the Preferred Alternative.
G. Hazards & Hazardous Materials
The impacts related to hazards and hazardous materials are relative to the number of people
impacted by these risks. The four differing Alternatives produce differing amounts of growth
and types of development, which may increase or decrease impacts related to hazards and
hazardous materials.
No Project Alternative
Build out under the No Project Alternative would result in a slightly higher number of residential
units and commercial square footage than the Preferred Alternative within the City Limits. This
would allow for a slight increase in population susceptible to hazards and hazardous materials, as
well as increased volumes of hazardous materials being generated by both residential and
commercial land uses.
In the Sphere of Influence, however, the No Project Alternative reduces the number of residential
units by almost half of what is proposed by the Preferred Alternative. This significantly reduces
the amount of residents susceptible to hazards and hazardous materials, and reduces the number
of people needing assistance during emergencies and evacuations. The reduced population,
however, is offset by the increased commercial uses proposed under the No Project Alternative.
Commercial land uses are almost double that proposed by the Preferred Alternative. Commercial
land uses typically generate higher volumes of hazardous materials than residential uses, and also
increase the amount of transport of these materials through the streets of the community. The No
Project Alternative, however, does not propose industrial uses. Industrial and light manufacturing
uses tend to increase the risks associated with hazardous materials. Overall, the No Project
Alternative is similar in regards to impacts associated with hazards and hazardous materials to
the Preferred Alternative.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-33
Alternative 1
Implementation of Alternative 1 would result in slightly fewer residential units and less
commercial square footage in the City than proposed under the Preferred Alternative. This would
slightly reduce impacts associated with hazards and hazardous materials. Alternative 1 would
also significantly reduce the amount of residential units over the Preferred Alternative in the
Sphere of Influence. Commercial uses are also slightly reduced under Alternative 1. Overall,
Alternative 1 would result in the lowest level of impact associated with hazards and hazardous
materials, of the Preferred Alternative and the two other Alternatives.
Alternative 2
Alternative 2 results in a slight increase in residential units and commercial uses over the
Preferred Alternative within the City limits. For the most part, impacts related to hazards and
hazardous waste would be similar under both Alternatives within the City limits. Alternative 2,
however significantly increases both residential and commercial uses in the Sphere of Influence
over the Preferred Alternative. Industrial uses proposed for the Sphere Influence, are nearly the
same between the two Alternatives. Therefore, this increase in residential and commercial uses
in the Sphere of Influence will increase the number of people at risk from hazardous spills and
accidents, and increase the volume of hazardous materials in the area. Alternative 2, therefore,
would have more significant impacts related to hazards and hazardous materials, than the
Preferred Alternative. Regulations and mitigation measures would be implemented in the same
manner as for the Preferred Alternative, however, and impacts would remain less than
significant.
H. Hydrology
The potential impacts to hydrology and drainage are primarily associated with land use
conversion and proposed development that results in a loss of, or reduction to permeability.
Although the four Alternatives propose various amounts of growth and types of development, all
Alternatives result in the development of approximately 30,957 acres throughout the Planning
Area. Development and urbanization of these lands has the potential to result in impacts to
hydrology due to paving of roads and sidewalks and impermeable building foundations. Water
that would have been absorbed into the ground will instead runoff to downstream areas, without
mitigation.
As noted in Section III-H the regional hydrology and drainage pattern, including flood control
structures, are managed and maintained by the Riverside County Flood Control and Water
Conservation District (RCFC) and CVWD.
All four alternatives, including the No Project Alternative, Alternative 1, Alternative 2, and the
Preferred Alternative, provide land use designations that allow for continued urbanization
throughout the Planning Area. As discussed below some alternatives propose more intense land
uses over others, which results in varying impacts to hydrology. Mitigation measures,
comparable to those listed in Section III-H will be required for each of the project alternatives.
These mitigation measures, along with local and regional flood control district policies and
regulations, are expected to reduce impacts to hydrology to less than significant levels for all
Alternatives.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-34
No Project Alternative
Implementation of the No Project Alternative has the potential to result in similar hydraulic
impacts within City limits as described in Section III under the Preferred Alternative analysis.
The overall Planning Area of the No Project Alternative will result in 9,229 fewer residential
dwelling units, but an additional 2.9 million square feet of commercial relative to the Preferred
Alternative. The No Project Alternative sets forth substantially fewer residential units within the
Sphere compared to the Preferred Alternative. As such, impacts to hydrology within the Sphere
will likely be somewhat reduced compared to the Preferred Alternative. As with the Preferred
Alternative, the No Project Alternative impacts to hydrology will primarily result from the
development of impermeable surfaces on currently vacant or undeveloped lands within the
Sphere.
Alternative 1
Implementation of Alternative 1 has the potential to result in similar hydraulic impacts within
City limits as described in Section III under the Preferred Alternative analysis. However, due to
the reduced level of development proposed under Alternative 1, impacts from flooding are
expected to be somewhat reduced compared to the Preferred Alternative. The overall Planning
Area of Alternative 1 will result in 10,399 fewer residential dwelling units, and 1.16 million
square feet less of commercial space relative to the Preferred Alternative.
Alternative 1 sets forth substantially fewer residential units within the Sphere compared to the
Preferred Alternative. As such, impacts to hydrology within the Sphere will likely be reduced
compared to the Preferred Alternative. Accordingly, Alternative 1 will have reduced runoff and
flooding, due to the reduced amount of impermeable surfaces that will be developed relative to
the Preferred Alternative. As with the Preferred Alternative, hydraulic impacts from Alternative
1 will primarily result from the development of impermeable surfaces on currently vacant or
undeveloped lands within the Sphere.
Alternative 2
At build out of Alternative 2 impacts to hydrology within City limits will be comparable to those
impacts described in Section III under the Preferred Alternative analysis. However, due to the
increased level of development proposed under Alternative 2, impacts from flooding are
expected to be somewhat increased compared to the Preferred Alternative. The overall Planning
Area of Alternative 2 will result in 3,955 additional residential dwelling units, and an additional
378,195 square feet of commercial space relative to the Preferred Alternative. Alternative 2 sets
forth 3,655 more residential units within the Sphere compared to the Preferred Alternative. As
such, impacts to hydrology within the Sphere will likely be increased compared to the Preferred
Alternative. Accordingly, Alternative 2 will result in increased impacts from runoff and flooding,
due to the additional impermeable surfaces that will be developed relative to the Preferred
Alternative. As with the Preferred Alternative, hydraulic impacts from Alternative 2 will
primarily result from the development of impermeable surfaces on currently vacant or
undeveloped lands within the Sphere.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-35
I. Land Use and Planning
The mix of uses proposed under each of the three Alternatives is analyzed relative to the
Preferred Alternative. Briefly, the Preferred Alternative is not expected to divide an established
community or conflict with the CV MSHCP.
As proposed, the Preferred Alternative is consistent with established land use plans for land use
designations proposed within City limits, but is somewhat divergent from the County’s land use
plan for the Sphere of Influence.
As described in detail in the Land Use and Planning discussion in Section III, land use
designations proposed for the Sphere of Influence have the potential to result in significant
impacts without mitigation. The City has studied the land use pattern in the Sphere, and has
considered several potential annexation proposals in the past. These proposals included analyses
relating to the availability and cost of the provision of services in the Sphere. These analyses
found that in the eastern Sphere in particular, lands have been encumbered by the County as
collateral for a regional bond issue. As a result, there will be no property tax generation to the
City from these lands for a number of years. The fiscal analysis concluded that the annexation of
property in the Sphere would have a negative fiscal impact on the City. Under all the proposed
alternatives, the potential fiscal impact to the City could be significant.
The General Plan includes policies that require both the preparation of fiscal impact analyses for
annexation proposals, and a Development Agreement in association with annexation. The
Development Agreement would establish the parameters for development, and would include
mitigation fee payments for projects that are fiscally negative for the City. These Development
Agreements would eliminate the potential fiscal impacts to the City under all alternatives.
No Project Alternative
The No Project Alternative includes a wide range of land use designations that have been
consolidated into a just a few land uses for the Preferred Alternative.
Build out of the No Project Alternative has the potential to result in the development of 43,875
dwelling units, which is 9,229 fewer dwelling units, or a 17% reduction compared to the
Preferred Alternative. This is primarily due to the differences in the allowable dwelling unit
densities for the Sphere of Influence, which nearly doubles for the Preferred Alternative
compared to the No Project Alternative.
Under the No Project Alternative, 15.28 million square feet of commercial land uses would be
developed throughout the Planning Area, which is 2.9 million square feet more than the
Preferred Alternative. For comparison purposes, the No Project Alternative proposes slightly
more commercial development within City limits and nearly doubles the proposed commercial
development within the Sphere of Influence compared to the Preferred Alternative. The
exception being that the Preferred Alternative includes 611,408 square feet of industrial/light
manufacturing land use, whereas the No Project Alternative does not include any industrial land
use designation.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-36
The land uses proposed under the No Project Alternative complement the existing land uses and
will not divide an established community. Proposed land uses for the No Project Alternative in
City limits are very similar to land uses proposed under the Preferred Alternative. Unlike the
Preferred Alternative, the No Project Alternative proposes land use designations for the Sphere
of Influence that are consistent with the County’s land use plan, including the Vista Santa Rosa
Concept. In addition, the No Project Alternative does not conflict with the established
CVMSHCP. Therefore, the No Project Alternative will result in less than significant impacts to
land use.
Alternative 1
When compared to the Preferred Alternative, Alternative 1 proposes 10,339 fewer dwelling
units, and 26,159 fewer residents would have the potential to be impacted by surrounding land
uses. The reduction in dwelling units under Alternative 1, relative to the Preferred Alternative, is
due to the different dwelling unit intensities proposed for the Sphere of Influence. The residential
land use for the Sphere of Influence under Alternative 1 is primarily very low density residential,
which only allows up to two dwelling units per acre, compared to the 4 dwelling units per acre
allowed under the Preferred Alternative. Alternative 1 would result in a reduction of 19% of total
residential units, when compared to the Preferred Alternative.
Alternative 1 also proposes a total of 11.2 million square feet of commercial development. The
level of development under this scenario is approximately 1.2 million square feet less than the
commercial development proposed under the Preferred Alternative. The potential Commercial
and Industrial square footage represents a reduction of 9.4% compared to the Preferred
Alternative.
Land uses proposed under Alternative 1 are consistent with those set forth under the Proposed
Alternative, but in less dense intensities. Potential land use impacts under Alternative 1 are
expected to be less than significant within City limits and the Sphere of Influence. Land uses
proposed under Alternative 1, within City limits, are consistent with the 2002 General Plan land
use designations. In addition, land use designations proposed for the Sphere of Influence, under
Alternative 1 are consistent with the County’s land use plan including the Vista Santa Rosa
Concept.
The land uses proposed under Alternative 1 complement existing land uses and would not divide
an established community. Proposed land uses for Alternative 1 are consistent with existing land
use plans and policies, and impacts are expected to be less than significant for proposed
development within City limits and the Sphere of Influence. In addition, Alternative 1 does not
conflict with the established CVMSHCP. Therefore, under Alternative 1 impacts to land use and
planning are expected to be less than significant.
Alternative 2
Under this Alternative, the Planning Area will experience a greater intensity of development
compared to the Preferred Alternative. Alternative 2 would allow for the development of up to
57,058 dwelling units, which could accommodate a population size of 144,357 residents at build
out. When compared to the Preferred Alternative, Alternative 2 proposes 3,955 additional
dwelling units and approximately 10,005 additional residents. Under Alternative 2, a greater
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-37
number of residents, a 7% increase over the Preferred Alternative, would have the potential to be
impacted by surrounding land uses.
Alternative 2 has the potential to result in the development of up to 12.74 million square feet of
commercial, which is an increase of 3% compared to the Preferred Alternative. Proposed
commercial development for Alternative 2 complements the existing commercial land uses and
is generally consistent with the Preferred Alternative.
As with the Preferred Alternative, potential land use impacts under Alternative 2 are expected to
be less than significant within City limits and have the potential to result in significant impacts
within the Sphere of Influence. Implementation of a master plan for the Sphere of Influence as
described in Section III of this EIR, will reduce potential impacts to land use and planning within
the Sphere of Influence to less than significant levels.
Alternative 2 is similar to the Preferred Alternative relative to potential impacts to land uses. The
land uses proposed under Alternative 2 complement the existing land uses and would not divide
an established community. In addition, Alternative 2 does not conflict with the established
CVMSHCP. With the adoption of a master plan for the Sphere of Influence, potential impacts
will be reduced. Implementation of mitigation measures for Alternative 2 will reduce land uses
impacts to level below significance.
J. Mineral Resources
The La Quinta General Plan Update Planning Area falls within the MRZ-1 and MRZ-3 mineral
resource zones. More than half of the City, and all of the Sphere of Influence, fall within MRZ-1.
This mineral zone includes areas where little likelihood exists for presence of significant mineral
resources. Incorporated lands within MRZ-1 are mostly built out, however vacant parcels still
exist. The Sphere of Influence is mostly agricultural development, and will most likely develop
into non-agricultural uses in the future. Future development within the MRZ-1, however, will
have a less than significant impact on mineral resources.
The far western portion of incorporated La Quinta falls within MRZ-3, which includes areas
containing known or inferred mineral deposits of undetermined mineral resource significance.
The majority of the MRZ-3 falls within protected open space, and remaining land is mostly
already developed. There are no locally important mineral resource extraction facilities in these
areas.
Existing land uses under the 2002 General Plan do not allow for mineral extraction under all
alternatives. The MRZ-3 zone is the only area where potential mineral resources exists, and these
areas are, for the most part, developed or designated as protected as open space. The Preferred
Alternative, along with the three other Alternatives, continue to provide open space across much
of MRZ-3, and promote similar development patterns across the remaining mineral resource
zones. Each Alternative, therefore, will have comparable impacts on mineral resources. The
MRZ-3 area is the only area within the Planning Area where significant mineral resources
potentially exist, however due to the fact that these areas are protected as open space, or are
mostly built out, the impacts on mineral resources by each Alternative is less than significant.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-38
K. Noise
As discussed in Section III-K, a comprehensive noise impact study was prepared to analyze
potential noise impacts associated with build out of the Preferred Alternative, and to assess the
relative noise impacts of each of the other development scenarios. The entire report is included in
Appendix F of this EIR. The following table summarizes the results. The study analyzed
roadway links in the planning area, and projected CNEL noise levels at 100 feet from the
roadway centerline for each project alternative.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-39
Table V-19
Year 2035 Preferred Alternative Noise Contour Comparison
CNEL at 100 Feet (dBA)
Roadway Segment
No Project
Alternative
Preferred
Alternative
Alternative
1
Alternative
2
Washington St. n/o Fred Waring Dr. 72.7 72.7 72.8 72.8
Washington St. btwn Fred Waring & Miles 73.2 73.3 73.2 73.3
Washington St. btwn Miles & Hwy 111 72.5 72.5 72.5 72.6
Washington St. btwn Hwy 111 & Avenue 48 72.9 73.0 73.0 73.0
Washington St. btwn Avenue 48 & Eisenhower Dr 73.0 72.3 73.0 73.0
Washington St. btwn Eisenhower Dr & Avenue 50 71.5 71.7 71.5 71.6
Washington St. btwn Avenue 50 & Calle Tampico 70.8 70.9 70.8 70.8
Eisenhower Dr. btwn Washington St & Avenue 50 68.1 68.1 68.1 68.1
Eisenhower Dr. btwn Avenue 50 & Calle Tampico 66.7 66.6 66.6 66.6
Avenida
Bermudas btwn Calle Tampico & Avenue 52 59.2 59.1 59.1 59.1
Avenida
Bermudas btwn Avenue 52 & Calle Durango 63.7 63.6 63.6 63.6
Adams St. btwn Westward Ho Dr & Hwy 111 66.5 66.6 66.6 66.7
Adams St. btwn Hwy 111 & Avenue 48 66.9 66.8 66.8 66.9
Dune Palms Rd. btwn Westward Ho Dr & Hwy 111 65.4 65.5 65.5 65.7
Dune Palms Rd. btwn Hwy 111 & Avenue 48 66.7 66.7 66.8 66.7
Jefferson St. n/o Fred Waring 70.4 70.4 70.5 70.5
Jefferson St. btwn Fred Waring & Miles 71.7 71.8 71.8 71.8
Jefferson St. btwn Miles & Westward Ho Dr 72.2 72.2 72.3 72.3
Jefferson St. btwn Westward Ho Dr & Hwy 111 72.2 72.2 72.3 72.3
Jefferson St. btwn Hwy 111 & Avenue 48 72.1 72.1 72.2 72.3
Jefferson St. btwn Avenue 48 & Avenue 50 72.6 72.7 72.7 72.8
Jefferson St. btwn Avenue 50 & Avenue 52 71.1 71.1 71.1 71.3
Jefferson St. btwn Avenue 52 & Avenue 54 70.6 70.7 70.6 70.7
Madison St. btwn Avenue 50 & Avenue 52 70.5 70.4 70.5 70.5
Madison St. btwn Avenue 54 & Airport Blvd 71.9 72.0 71.9 72.0
Madison St. btwn Airport Blvd & Avenue 58 70.7 70.8 70.7 70.8
Madison St. btwn Avenue 58 & Avenue 60 68.0 68.2 68.1 68.2
Monroe St. btwn Avenue 52 & Avenue 54 70.3 70.4 70.3 70.4
Monroe St. btwn Avenue 54 & Airport Blvd 70.5 70.6 70.4 70.7
Jackson St. btwn Avenue 54 & Airport Blvd 70.1 70.0 69.9 70.1
Jackson St. btwn Airport Blvd & Avenue 58 70.2 70.2 70.0 70.4
Jackson St. btwn Avenue 58 & Avenue 60 69.3 69.5 69.5 69.7
Jackson St. btwn Avenue 60 & Avenue 62 68.0 68.3 68.2 68.4
Van Buren St. btwn Avenue 52 & Avenue 54 69.8 70.0 69.6 70.2
Van Buren St. btwn Avenue 54 & Airport Blvd 69.1 69.0 68.8 69.1
Van Buren St. btwn Airport Blvd & Avenue 58 69.4 69.3 69.2 69.4
Van Buren St. btwn Avenue 58 & Avenue 60 69.5 69.4 69.3 69.3
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-40
Table V-19
Year 2035 Preferred Alternative Noise Contour Comparison
CNEL at 100 Feet (dBA)
Roadway Segment
No Project
Alternative
Preferred
Alternative
Alternative
1
Alternative
2
Van Buren St. btwn Avenue 60 & Avenue 62 66.0 65.8 65.7 65.8
Harrison St. btwn Airport Blvd & Avenue 58 73.4 73.7 73.6 73.8
Avenue 44 e/o Washington St 71.9 72.0 72.0 72.1
Miles Ave. e/o Washington St 66.5 66.6 66.5 66.6
Hwy 111 e/o Washington St 75.5 75.4 75.5 75.6
Hwy 111 e/o Adams St 74.3 74.2 74.6 74.7
Hwy 111 e/o Dune Palms 75.2 75.2 75.2 75.4
Avenue 48 e/o Washington St 67.0 67.0 67.0 67.1
Avenue 48 w/o Jefferson St 70.1 70.0 70.1 70.1
Avenue 50 e/o Washington St 64.4 64.4 64.4 64.4
Avenue 50 w/o Jefferson St 67.2 67.0 67.1 67.1
Avenue 50 e/o Jefferson St 69.6 69.7 69.7 69.7
Calle Tampico btwn Eisenhower Dr & Avenida
Bermudas 61.9 61.9 61.9 61.9
Calle Tampico btwn Avenida Bermudas &
Washington St 64.7 64.7 64.7 64.7
Avenue 52 w/o Washington St 66.7 66.7 66.7 66.7
Avenue 52 w/o Jefferson St 70.0 70.1 70.0 70.1
Avenue 52 e/o Jefferson St 69.7 69.7 69.6 69.8
Avenue 52 e/o Madison St 69.2 69.2 69.3 69.3
Avenue 54 e/o Jefferson St 69.8 69.9 69.8 70.0
Avenue 54 w/o Madison St 62.4 62.4 62.4 62.4
Airport Blvd. e/o Madison St 67.3 67.3 67.0 67.4
Avenue 58 w/o Monroe St 63.3 63.8 63.4 63.9
Avenue 58 e/o Monroe St 65.6 66.0 65.6 66.1
Avenue 60 e/o Madison St 63.5 64.9 64.6 65.1
Avenue 60 e/o Monroe St 65.0 65.3 65.0 65.4
Avenue 62 btwn Madison St & Monroe St 64.2 64.3 64.1 64.4
Avenue 62 e/o Monroe St 67.5 67.5 67.4 67.4
Avenue 62 e/o Jackson St 63.4 63.7 63.6 63.6
Avenue 62 e/o Van Buren St 59.9 60.1 59.9 59.8
Source: City of La Quinta General Plan Update Noise Element Technical Report”, prepared by Urban Crossroads,
Inc., June 3, 2011
1. A significant impact is considered both a level above 65 dBA CNEL and an increase greater than 3.0 dBA.
Noise levels along approximately 55 roadway segments in the Planning Area are projected to
exceed the 65 dBA CNEL at 100 feet from the roadway centerline at build out of the Preferred
Alternative. As discussed in Section III-K, the Preferred Alternative is not expected to result in
increases in noise levels over existing conditions that are perceptible (equal to or greater than 3
dBA) along any roadway segments in the planning area.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-41
No Project Alternative
As shown in the table above, noise levels along approximately 54 roadway segments in the
Planning Area are projected to exceed the 65 dBA CNEL at 100 feet from the roadway centerline
at build out of the No Project Alternative. This is only one road segment less than the Preferred
Alternative. Noise levels along 21 evaluated roadway segments under the No Project Alternative
are expected to be less than the Preferred Alternative. These noise reductions are less than 3
dBA, which are barely perceptible to the human ear. Noise levels along 4 roadway segments are
expected to be greater than the Preferred Alternative, however, these differences are still less
than 3 dBA, which are considered imperceptible. Finally, noise levels along 23 roadway
segments at build out of the No Project Alternative are expected to be the same as those
projected for the Preferred Alternative. Overall, the noise levels for the No Project Alternative
are similar to noise levels projected under the Preferred Alternative. The same mitigation
measures, including requirements for acoustical analysis for project occurring along impacted
roadways, would apply for all alternatives, and would reduce impacts to less than significant
levels.
Alternative 1
The Alternative 1 is expected to increase average noise levels by approximately 0.04 dBA CNEL
over the No Project Alternative. Along 29 roadway segments, increased noise levels are expected
to be higher than the No Project Alternative, however this noise increase will be less than 3 dBA,
which is imperceptible to land uses.
As compared with the Preferred Alternative, Alternative 1 is expected to decrease average noise
levels by approximately 0.02 dBA CNEL. Along 26 roadway segments, Alternative 1 will result in
noise levels that are less than those projected for the Preferred Alternative, however these noise
level changes are less than 3 dBA, which are considered imperceptible. Alternative 1 will result in
noise levels that are the same along 22 of the evaluated roadway segments compared to the
Preferred Alternative. Alternative 1 will result in noise levels that are higher along 18 of the
evaluated roadway segments compared to the Preferred Alternative. Along all roadway segments,
decreased noise levels are expected to be imperceptible compared to the Preferred Alternative.
Alternative 1 is expected to result in increased noise levels along 8 roadway segments as compared
with the Preferred Alternative. Of these, increases along one of the roadway segments would be
considered potentially audible. The same mitigation measures, including requirements for
acoustical analysis for project occurring along impacted roadways, would apply for all
alternatives, and would reduce impacts to less than significant levels.
Alternative 2
Alternative 2 will result in an average increase of approximately 0.1 dBA CNEL over the No
Project Alternative. Alternative 2 is projected to result in a maximum increase in noise level of
only 1.5 dBA CNEL over the No Project Alternative, which includes the location along Avenue
60, east of Madison Street. Along 47 roadway segments, increased noise levels are expected to be
higher than the No Project Alternative, however this noise increase will be less than 3 dBA, which
is imperceptible to land uses. Alternative 2 is expected to result in noise impacts that are the same as
those of the No Project Alternative along 16 of roadway segments evaluated, and decreased noise
levels along 3 roadway segments.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-42
Compared to the Preferred Alternative, Alternative 2 is expected to result in noise impacts that are
similar to the Preferred Alternative along 23 of roadway segments evaluated. Noise levels along 38
roadway segments under Alternative 2 are projected to exceed those of the Preferred Alternative,
which includes a noise level increase of 0.7 dBA along Washington Street, between Avenue 48 and
Eisenhower Drive. Noise levels that are less than those expected by the Preferred Alternative are
projected along 5 roadway segments, however, the differences are expected to be imperceptible.
Noise increases equal to or greater than 3 dBA more than the Preferred Alternative are not projected
to occur along any of the evaluated roadway segments. Therefore, the noise impacts associated with
Alternative 2 are similar to the Preferred Alternative. The same mitigation measures, including
requirements for acoustical analysis for project occurring along impacted roadways, would apply
for all alternatives, and would reduce impacts to less than significant levels.
Overall, noise impacts will be less, when compared to the Preferred Alternative, under the No
Project Alternative and Alternative 1, although the difference is not expected to be significant.
Under Alternative 2, noise levels will be only marginally higher. Increases in noise levels are not
expected to exceed 3 dBA among each Alternative, which is considered imperceptible and
insignificant. For all the alternatives, the mitigation measures included in Section III-L would be
required, and impacts would be reduced to less than significant levels at build out.
L. Population and Housing
Impacts associated with population and housing as a result of implementation of the Preferred
Alternative are discussed in Section III-L. Implementation of the General Plan Update will result
in growth that is consistent with growth projections within City limits, but has the potential to
increase the projected population and housing unit development within the Sphere of Influence
relative to existing growth projections. Therefore, the Preferred Alternative has the potential to
induce substantial growth and result in significant impacts. In order to reduce potential impacts
from growth and development within the Sphere of Influence, a master plan will be prepared.
Adoption of such a Plan is expected to be sufficient to mitigate potential impacts from growth
and development in the Sphere of Influence.
No Project Alternative
The No Project Alternative has the potential to result in the development of 43,875 dwelling
units and support 111,004 residents, which is 9,228 fewer dwelling units and 23,348 fewer
residents compared to the Preferred Alternative. The No Project Alternative would allow for a
total of 15.28 million square feet of commercial land uses, which is 2.91 million square feet
greater than the Preferred Alternative, or an increase of 24%. The No Project Alternative is
consistent with current growth projections and will result in less than significant impacts to
population and housing.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-43
Alternative 1
Alternative 1 proposes 10,339 fewer dwelling units and 26,159 fewer residents compared to the
Preferred Alternative. The reduction in dwelling units under Alternative 1, relative to the
Preferred Alternative, is due the different dwelling unit densities proposed for the Sphere of
Influence. Alternative 1 proposes 11,333 units compared to the 21,500 dwelling units proposed
under the Preferred Alternative, and results in nearly doubling the potential build out population
for the Sphere of Influence (a population of 28,672 under Alternative 1, compared to 54,396
under the Preferred Alternative). Alternative 1 would result in a reduction of 19% of total
residential units, when compared to the Preferred Alternative. Thus, Alternative 1 is consistent
with existing growth projections and impacts are expected to be less than significant.
Alternative 2
The Planning Area will experience a greater intensity of development under the More Intense
Alterative when compared to the Preferred Alternative. Alternative 2 would allow for the
development of up to 57,058 dwelling units, which could accommodate a population size of
144,357 residents at build out, consisting of 80,715 people within City limits and 63,642 people
within the Sphere of Influence. When compared to the Preferred Alternative, Alternative 2
proposes 3,955 additional dwelling units and approximately 10,005 additional residents.
As with the Preferred Alternative, Alternative 2 is consistent with growth projections within City
limits, but exceeds growth projections in the Sphere of Influence. Due to the projected
population size for the Sphere of Influence the More Intense Project Alternative has the potential
to result in significant impacts to population and housing. In order to mitigation potential impacts
and achieve levels below significance, a master plan will be prepared. As described under the
Preferred Alternative, adoption of such a Plan is expected to be sufficient to mitigate potential
impacts from growth and development in the Sphere of Influence to levels below significance.
M. Public Service and Utilities
1. Schools
The estimated student enrollment at build out of each project alternative is shown in the
following tables.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-44
Table V-20
Potential School Enrollment at General Plan Build Out , No Project Alternative
Grade Level Max. Student Projected
Enrollment Build out Units Generation Rate
Elementary (K-6)
Single Family 34,798 0.214 7,447
Multi-Family 9,076 0.1267 1,150
Elementary Subtotal 8,597
Middle (7-8)
Single Family 34,798 0.1093 3,803
Multi- Family 9,076 0.0522 474
Middle School Subtotal 4,277
High School (9-12)
Single Family 34,798 0.1427 4,966
Multi-Family 9,076 0.0543 493
High School Subtotal 5,459
Total 43,875 18,333
Source: Terra Nova Staff Estimates based on Student Generation Rates, Desert Sands Unified School
District Master Facilities Plan, October 2008.
Table V-21
School Enrollment at General Plan Build Out, Alternative 1
Grade Level Max. Student Projected
Enrollment Build out Units Generation Rate
Elementary (K-6)
Single Family 36,636 0.214 7,840
Multi-Family 6,128 0.1267 776
Elementary Subtotal 8,617
Middle (7-8)
Single Family 36,636 0.1093 4,004
Multi- Family 6,128 0.0522 320
Middle School Subtotal 4,324
High School (9-12)
Single Family 36,636 0.1427 5,228
Multi-Family 6,128 0.0543 333
High School Subtotal 5,561
Total 42,764 18,501
Source: Terra Nova Staff Estimates based on Student Generation Rates, Desert Sands Unified School
District Master Facilities Plan, October 2008.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-45
Table V-22
School Enrollment at General Plan Build Out
Alternative 2
Grade Level Max. Student Projected
Enrollment Build out Units Generation Rate
Elementary (K-6)
Single Family 45,032 0.214 9,637
Multi-Family 12,026 0.1267 1,524
Elementary Subtotal 11,161
Middle (7-8)
Single Family 45,032 0.1093 4,922
Multi- Family 12,026 0.0522 628
Middle School
Subtotal
5,550
High School (9-12)
Single Family 45,032 0.1427 6,426
Multi-Family 12,026 0.0543 653
High School Subtotal 7,079
Total 57,058 23,789
Terra Nova Staff Estimates based on Student Generation Rates, Desert Sands Unified School
District Master Facilities Plan, October 2008.
Comparable tables for the Preferred Alternative, shown in Section III-M, estimate a build out
student population of 23,294 in the City and Sphere combined. At build out, the No Project
Alternative is expected to generate 18,333 students, which equates to 21.3% fewer students than
the Preferred Alternative. By comparison, Alternative 2 would generate 23,789 students, or an
increase of approximately 2.1% students over the Preferred Alternative. Estimated student
generation associated with Alternative 1 will be 18,501 students, or approximately 20.6% less
than the Preferred Alternative. Student generation within the Sphere is included in these
estimates. Based on these figures, the student population in the Sphere would be expected to
account for between 28.5% and 43.5% of the total student population for the respective
alternatives.
The highest number of students will be generated by Alternative 2. Therefore, this alternative is
expected to result in the greatest impact on public schools serving the Planning Area. Based on
these estimates, it is anticipated that the No Project and Alternative 1 would result in the least
impact on school enrollment.
Student enrollment will depend on actual development, and in any case will gradually increase as
new development facilitated by implementation of the proposed General Plan builds out. As
noted in Section III-M, future development will be required to offset potential impacts by paying
statutory developer fees. These fees will be required of any of the development scenarios, and
are expected to mitigate potential impacts to public schools to less than significant levels.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-46
2. Libraries
Based on the County Library System’s unadopted target of 2 volumes per capita, the estimated
build out population of 134,352 in the planning area will require 268,704 volumes at build out of
the Preferred Alternative.
As discussed in Section III-M for the Preferred Alternative, each of the alternatives will generate
Developer Impact Fees (DIF) as new units are constructed to offset increased demands
associated with library facilities and services. These are one-time fees, and will only be assessed
at the time these units are built. DIF fees for the Preferred Alternative were estimated to be
approximately $10.2 million. Estimated fees for each Alternative are presented below.
Under any of the development scenarios, growth will occur gradually, thus incrementally
increasing demand on library services and facilities. To assure that there continue to be adequate
library services and facilities to serve the community, the City of La Quinta and Riverside
County will need to continue to monitor library use. Mitigation measures set forth in Section III-
M reduce impacts to libraries to levels below significance for all of the project alternatives.
As previously described, fiscal analyses have found that in the eastern Sphere in particular, lands
have been encumbered by the County as collateral for a regional bond issue. As a result, there
will be no property tax generation to the City from these lands for a number of years. The fiscal
analysis concluded that the annexation of property in the Sphere would have a negative fiscal
impact on the City. The General Plan includes policies that require both the preparation of fiscal
impact analyses for annexation proposals, and a Development Agreement in association with
annexation. The Development Agreement would establish the parameters for development, and
would include mitigation fee payments for projects that are fiscally negative for the City. These
Development Agreements would eliminate the potential fiscal impacts to the City under all
Alternatives.
No Project Alternative
The No Project Alternative is expected to generate a build out population of approximately
111,004. Applying the County’s unadopted standard of 2 volumes per capita, at build out
approximately 222,008 volumes would be required to serve the population. Population within the
City limits accounts for 161,566 volumes, and population within the Sphere accounts for 60,442
volumes within Sphere areas. The No Project Alternative would generate a similar demand for
new library services. The No Project would require approximately 17.4% fewer volumes than
the Preferred Alternative.
Based on current fees, new residential development under the No Project Alternative will
generate approximately $6.9 million in library fees.
Alternative 1
Under Alternative 1, which is expected to result in a build out population of 108,193
approximately 216,386 volumes would be needed. Of these, 159,040 would be required for the
population in the City limits, and 57,344 for the population in the Sphere. The Alternative 1
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-47
would generate a similar demand for new library services. Alternative 1 will generate a demand
for approximately 19.5% fewer volumes relative to the Preferred Alternative.
Alternative 1 will generate approximately $6.53 million in DIF fees due to the proposed
development set forth under Alternative 1.
Alternative 2
At build out it is estimated Alternative 2 will result in a population of 144,357 persons. This
level of development would require 288,714 volumes, of which 161,430 would be needed for
population in the City limits, and 127,284 for the Sphere. Alternative 2 would require
approximately 7.4% more volumes than would the Preferred Alternative.
Alternative 2 will generate approximately $11.57 million in DIF fees due to the proposed
development set forth under this alternative.
3. Law Enforcement
The greatest level of additional demand for police services will be generated by Alternative 2,
followed by the Preferred Alternative. The Less Intense and No Project Alternatives,
respectively, will place the least additional demand on police services. The City will incur
additional costs for the provision of these services, regardless of the alternative.
The need for additional police staffing will occur gradually as development builds out in the
Planning Area. Section III-M sets forth mitigation measures that are intended to reduce potential
impacts to less than significant levels for all alternatives.
As previously described, fiscal analyses have found that in the eastern Sphere in particular, lands
have been encumbered by the County as collateral for a regional bond issue. As a result, there
will be no property tax generation to the City from these lands for a number of years. The fiscal
analysis concluded that the annexation of property in the Sphere would have a negative fiscal
impact on the City. The General Plan includes policies that require both the preparation of fiscal
impact analyses for annexation proposals, and a Development Agreement in association with
annexation. The Development Agreement would establish the parameters for development, and
would include mitigation fee payments for projects that are fiscally negative for the City. These
Development Agreements would eliminate the potential fiscal impacts to the City under all
Alternatives.
No Project Alternative
Under the No Project Alternative, the build out population will be approximately 111,004.
Although, as discussed in Section III-M, there is no adopted staff-to-population standard in La
Quinta, Riverside County Sheriff’s Department strives for a ratio of approximately 1 officer per
1,000 population. Based on this ratio, 111 police officers will be required to serve the build out
population, of which 81 will be associated with increased population in the City and 30 with the
Sphere. Compared with the Preferred Alternative, the No Project Alternative requires 23 fewer
Officers. This represents a decrease of approximately 17.2%.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-48
Alternative 1
At build out the population associated with Alternative 1 will be of 108,193. This level of
development will generate demand for 109 police officers, or approximately 18.7% less than the
Preferred Alternative. Approximately 80 police officers would be required based on the
estimated build out population in the City, and 29 would be required in the Sphere.
Alternative 2
Alternative 2 will result in a build out population of 144,357, thus requiring 145 police officers.
This represents an increase of 11 officers, or an approximately 8.2% increase over the Preferred
Alternative. Alternative 2 build out population in the City would require approximately 81
officers, and the Sphere would require approximately 64 officers in the total increase in staffing.
4. Fire Protection
As discussed in Section III-M, fire protection services are provided to the Planning Area by the
Riverside County Fire Department. The County is in the process of evaluating and updating the
standards by which it determines the need for additional fire staffing, equipment and facilities.
Currently there are three fire stations in La Quinta, with stations in neighboring cities also
available to serve the Planning Area as needed.
Based on projected build out population, it is expected that Alternative 2 will generate the
greatest increased demand for fire protection services, while Alternative 1 will result in the least
additional demand. Regardless of the development scenario that is implemented, additional fire
protection services will be required, including personnel and equipment, and may necessitate the
construction of additional fire stations. The County monitors growth within the jurisdictions it
serves, and future development projects will continue to be subject to Fire Department review to
ensure the adequate provision of fire protection services. Mitigation measures are set forth in
Section III-M that will apply to any of the alternatives, and will reduce potential impacts
associated provision of fire services to less than significant levels.
As previously described, fiscal analyses have found that in the eastern Sphere in particular, lands
have been encumbered by the County as collateral for a regional bond issue. As a result, there
will be no property tax generation to the City from these lands for a number of years. The fiscal
analysis concluded that the annexation of property in the Sphere would have a negative fiscal
impact on the City. The General Plan includes policies that require both the preparation of fiscal
impact analyses for annexation proposals, and a Development Agreement in association with
annexation. The Development Agreement would establish the parameters for development, and
would include mitigation fee payments for projects that are fiscally negative for the City. These
Development Agreements would eliminate the potential fiscal impacts to the City under all
Alternatives.
5. Electricity
Projected electric power demand for the Planning Area has been estimated based on historical
usage factors in La Quinta provided by IID, applied to residential, commercial, and industrial
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-49
development in the Planning Area. The following are electric consumption estimates at build out
for each project alternative.
No Project Alternative
City Limits: 1,121,724,203 kilowatt hour/year
Sphere: 499,422,871 kilowatt hour/year
Planning Area: 1,621,147,074 kilowatt hour/year
Alternative 1
City Limits: 1,059,057,498 kilowatt hour/year
Sphere: 342,918,007 kilowatt hour/year
Planning Area: 1,401,975,505 kilowatt hour/year
Alternative 2
City Limits: 1,094,274,318 kilowatt hour/year
Sphere: 637,122,426 kilowatt hour/year
Planning Area: 1,731,396,774 kilowatt hour/year
Existing and future residential, commercial and industrial development in the planning area
under the Preferred Alternative is expected to generate demand for 1,645,145,600 kilowatt-hours
per year at build out. By comparison, the No Project Alternative is expected to generate
approximately 1.5% less demand for electricity than the Preferred Alternative. The Alternative 1
is expected to generate approximately 14.8% less demand, while Alternative 2 will generate
approximately 5% greater demand than the Preferred Alternative. Estimates include both the
City limits and the Sphere.
Impacts will be less than significant for any of the development scenarios.
6. Natural Gas
In Section III-M, it is estimated that development facilitated by the Preferred Alternative will
consume approximately 2,238,326,502 cubic feet/year of natural gas at build out. The following
estimates potential demand for natural gas for each of the project alternatives.
No Project Alternative
City Limits: 1,467,168,248 cubic feet/year
Sphere: X cubic 622,238,575 cubic feet/year
Planning Area: 2,089,406,823 cubic feet/year
Alternative 1
City Limits: 1,402,741,087 cubic feet/year
Sphere: 469,980,612 cubic feet/year
Planning Area: 1,872,721,699 cubic feet/year
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-50
Alternative 2
City Limits: 1,441,566,735 cubic feet/year
Sphere: 929,123,261 cubic feet/year
Planning Area: 2,370,689,995 cubic feet/year
Based on the above estimates, all development associated with Alternative 2, including the City
and Sphere, will consume approximately 5.6% more natural gas than the Preferred Alternative.
Comparatively, the Less Intense will consume approximately 10.4% less than the Preferred
Alternative, and the No Project approximately 6.7% less.
Of all the alternatives, the lowest natural gas consumption will result from Alternative 1. For any
of the project alternatives, build out will occur gradually over time as development occurs. All
alternatives will result in less than significant impacts.
7. Domestic Water Services
An increase in demand on water resources will result from future development associated with
any of the project alternatives. Each will require the construction and expansion of facilities and
infrastructure to serve new development. The analysis provided in Section III-M considers in
detail the existing conditions associated with water resources and water quality. It also discussed
potential impacts associated with the Preferred Alternative. Estimated water consumption for
each alternative is shown in Section V-P below.
8. Wastewater Collection and Treatment
Potential wastewater generation in the Planning Area is estimated for the Preferred Alternative in
Section III-M. The estimated wastewater generation for the Preferred Alternative at build out is
projected to be approximately 4.4 million gallons per day within City limits and 3.0 million
gallons per day within the Sphere. Thus, the total wastewater generation within the Planning
Area is estimated to be 7.4 million gallons per day.
The wastewater generation rate for each Alternative is assumed to be equal to the potable water
demand that is projected to be generated, see Table V-23 through V-25. These projections
assume an average water demand of approximately 69.3 gallons per capita per day in 2010 and
are projected to average 55.44 gpcd at build out. Based on these assumptions, the estimated
wastewater generation for each of the alternatives at build out is shown below.
No Project Alternative
City: 4,478,610 gallons/ day
Sphere: 1,675,452 gallons/day
Planning Area: 6,154,062 gallons/day
Alternative 1
City: 4,408,589 gallons/ day
Sphere: 1,589,576 gallons/day
Planning Area: 5,998,165 gallons/day
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-51
Alternative 2
City: 4,474,840 gallons/ day
Sphere: 3,528,312 gallons/day
Planning Area: 8,003,152 gallons/day
The highest volume of wastewater generation is expected to result from Alternative 2,
approximately 7% more than the Preferred Alternative. The least wastewater generation is
expected for Alternative 1; this alternative will generate 19.5% less than the Preferred
Alternative. The No Project Alternative will generate approximately 17.4% less wastewater than
the Preferred Alternative.
The greatest demand on wastewater collection and treatment facilities will come from
Alternative 2. The least wastewater-generating alternatives are the No Project and Alternative 1s.
Regardless of which alternative is implemented, future development will place additional
demands on these facilities. The City and Coachella Valley Water District will need to continue
to monitor growth and plan for new facilities. Potential impacts will be reduced to less than
significant levels with the application of mitigation measures set forth in Section III-M; these
measures will apply to any of project alternatives.
11. Solid Waste Management
Section III-M provides estimates of solid waste generation for the Preferred Alternative. The
Preferred Alternative is estimated to generate approximately 139,181.08 tons of solid waste
annually at build out.
Estimated solid waste for each of the project alternatives at General Plan build out is shown in
the following tables.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-52
Table V-23
Estimated Solid Waste Generation for La Quinta Planning Area
No Project
Land Use Type
Generation
Rate
Unit
Type
Units
(DU/Sq. Ft.)
Annual Tons
of Solid Waste
Single Family 2.0400 tons/unit/year 34,798 70,988.74
Multi Family 1.1700 tons/unit/year 9,076 10,619.15
Retail/Commercial1 0.0024 tons/sf/year 15,275,317 36,660.76
Industrial 0.0108 tons/sf/year 0 0.00
Total 118,268.65
1Assumes development of all General, Tourist and Village Commercial based on retail/commercial factor.
Source: Terra Nova staff estimates based on California Integrated Waste Management Board compilation of
waste generation rates. Rates used are from Ventura County Solid Waste Management Department,
“Guidelines for Preparation of Environmental Assessments of Solid Waste Impacts”, September 1992, and
“DEIR for North Hills Development in Santa Clarita”, December 1991.
Table V-24
Solid Waste Generation for Planning Area
Alternative 1
Land Use Type
Generation
Rate
Unit
Type
Units
(DU/Sq. Ft.)
Annual Tons
of Solid Waste
Single Family 2.04 tons/unit/year 36,636 74,737.44
Multi Family 1.17 tons/unit/year 6,128 7,169.76
Retail/Commercial1 0.0024 tons/sf/year 11,199,642 26,879.14
Industrial 0.0108 tons/sf/year 611,393 6,603.04
Total 115,389.39
1 Assumes development of all General, Tourist and Village Commercial based on retail/commercial factor.
Source: Terra Nova staff estimates based on California Integrated Waste Management Board compilation of
waste generation rates. Rates used are from Ventura County Solid Waste Management Department,
“Guidelines for Preparation of Environmental Assessments of Solid Waste Impacts”, September 1992, and
“DEIR for North Hills Development in Santa Clarita”, December 1991..
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-53
Table V-25
Solid Waste Generation for Planning Area
Alternative 2
Land Use Type
Generation
Rate
Unit
Type
Units
(DU/Sq. Ft.)
Annual Tons
of Solid Waste
Single Family 2.0400 tons/unit/year 45,032 91,865.28
Multi Family 1.1700 tons/unit/year 12,026 14,070.42
Retail/Commercial1 0.0024 tons/sf/year 12,742,826 30,582.78
Industrial 0.0108 tons/sf/year 611,393 6,603.04
Total 143,121.53
1Assumes development of all General, Tourist and Village Commercial based on retail/commercial factor.
Source: Terra Nova staff estimates based on California Integrated Waste Management Board compilation of
waste generation rates. Rates used are from Ventura County Solid Waste Management Department,
“Guidelines for Preparation of Environmental Assessments of Solid Waste Impacts”, September 1992, and
“DEIR for North Hills Development in Santa Clarita”, December 1991.
The tables above show estimates for existing and future development within the City and Sphere.
Based on these estimates, it is expected that the No Project alternative will generate
approximately 15.0% less solid waste than the Preferred Alternative. The Less Intense will
generate approximately 17.1% less than the Preferred; the More Intense will generate
approximately 2.8% more solid waste than the Preferred Alternative.
It should be noted that although each of the development scenarios will contribute to the waste
stream, the mitigation measures set forth in Section III-M are applicable to any of the
alternatives. With the implementation of these measures, potential impacts are expected to be
reduced to less than significant levels, regardless of the alternative that is implemented.
N. Recreational Resources
The City of La Quinta has established criteria, based on the Quimby Act, for dedicating land for
parks or payment of in lieu fees for new recreational resources. Residential projects containing
more than five parcels are required to pay a park development fee or dedicate three acres of land
for parks per one thousand people in a new subdivision.
Under the Preferred Alternative, build out of the General Plan Update will result in a population
of 79,956 people and require 240 acres of parks and recreational facilities within the city limits.
Within the Sphere of Influence, build out under the Preferred Alternative will create a population
of 54,396 people, and require 163 acres of parks and recreational facilities. In total, the Preferred
Alternative will create a population of 134,352 at build out, and will require the development of
403 acres of recreational resources.
No Project Alternative
Build out under the No Project Alternative is expected to provide 31,930 residential units, and
create a population of 80,783 within the City. Under these circumstances, the No Project
Alternative will require approximately 242 acres or parkland in the City. This represents less
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-54
than 1% increase in both population and the amount of parkland needed in the City over the
Preferred Alternative. Therefore, the impact on recreational resources under the No Project
Alternative will be slightly higher than the Preferred Alternative within the City Limit.
In regards to the Sphere of Influence, the No Project Alternative is expected to provide 11,945
dwelling units, creating a population of 30,221 people. The Sphere of Influence will require
approximately 91 acres of parkland and recreational opportunities. This represents a 43%
decrease in population and recreational demand over the Preferred Alternative. Therefore,
impacts on recreational resources under the No Project Alternative will be significantly less than
the Preferred Alternative within the Sphere of Influence.
Overall, the No Project Alternative will create a population of 111,004, and will require 333
acres set aside for recreational resources. The No Project Alternative, therefore, will have
slightly less impact on recreational resources than the Preferred Alternative.
Alternative 1
Implementation of Alternative 1 is expected to provide for 31,431 residential units, and create a
total population of 79,520 within the City. This will create a need for 239 acres of parks and
recreation resources. This represents a less than 1% decrease in population and recreational
resource demand over the Preferred Alternative. Alternative 1 will, therefore, have slightly lower
impacts on recreational resources than the Preferred Alternative within the City.
Within the Sphere of Influence, Alternative 1 is expected to provide 11,333 residential units,
creating a population of 28,672 people. This will require 86 acres of parkland and recreational
resources. This represents a 47% decrease in population and recreation resource demand over the
Preferred Alternative. Impacts to recreational resources under Alternative 1, therefore, will be
lower than the Preferred Alternative within the Sphere of Influence.
Overall, Alternative 1 will create a population of 108,193, and will require 325 acres to be set
aside for recreational resources. Alternative 1, therefore, will have the lowest impact on
recreational resources than all the alternatives.
Alternative 2
Alternative 2 is expected to provide 31,903 residential units, creating a population of
approximately 80,715 people in the City. This population will require 242 acres to be set aside
for parks and recreation. This represents a less than 1% increase in population and recreational
resource demand over the Preferred Alternative. Therefore, the impact on recreational resources
under Alternative 2 will be only marginally higher than the Preferred Alternative within the City.
In regards to the Sphere of Influence, Alternative 2 is expected to provide up to 25,155
residential units, creating a population of 63,642 people. This population will require 191 acres
of parkland and recreational resources. This represents a 17% increase in population and
recreation resource demand over the Preferred Alternative. Impacts to recreational resources
under Alternative 2, therefore, will be slightly higher than the Preferred Alternative within the
Sphere of Influence.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-55
Overall, Alternative 2 will create a population of 144,357, and will require 433 acres set aside for
recreational resources. Alternative 2, therefore, will have greater impact on recreational
resources than the Preferred Alternative.
O. Transportation/Traffic
The purpose of this discussion is to analyze and compare the traffic impacts associated with each
of the alternative projects. A discussed at the beginning of this section, the No Project
Alternative is the build out of the current City General Plan. This analysis also examines the
consequences of two other alternative land use allocation models. The Preferred Alternative calls
for 53,103 dwelling units and 12.4 million square feet of commercial and industrial. The socio-
economic data for the Preferred Alternative total 134,352 residents and 33,780 jobs. Also see
Section III-O of this EIR for a detailed analysis of the transportation consequences of the
Preferred Alternative. Table V-26 provides a summary of the Preferred Land Use Plan, 2002
General Plan, Alternative 1, and Alternative 2 attributes.
Table V-26
Comparison of Land Use Alternatives
Attribute Preferred
Alternative
No Project
Alternative Alternative 1 Alternative 2
Total Population 134,352 111,004 108,193 144,357
Total Employment 33,780 32,041 32,194 34,507
Total Intersection Delay (a.m. peak
hour) 4,919.3 4,502.2 4,721.1 5,045.4
Total Intersection Delay (p.m. peak
hour) 7,802.0 7,571.8 7,673.2 7,907.9
Notes:
Delay = Average Vehicle Delay (Seconds)
Build out of this Preferred Alternative is forecast to result in peak season cumulative intersection
delays, at the 37 study intersections, totaling 4,919 seconds during the a.m. peak period and
7,802 seconds during the p.m. peak period. Please note that this analysis for all alternatives
assumes the build out of roadway improvements set forth in the 2002 General Plan.
No Project Alternative
Build out of the No Project (2002 General Plan) Alternative would result in total a.m. peak hour
volumes at the study intersections that are approximately 3% lower than result from build out of
the Preferred Alternative. The 2002 General Plan total p.m. peak hour volumes are forecast to be
approximately 1% lower than the Preferred Alternative.
The total a.m. peak hour delay at the study intersections in the 2002 General Plan is forecast to
be approximately 8% lower than the Preferred Alternative. The total p.m. peak hour delay at the
study intersections in the 2002 General Plan is forecast to be approximately 3% lower than the
Preferred Land Use Plan, with 4,502.2 seconds of delay during the AM peak and 7,571.8 seconds
of delay during the PM peak. Detailed forecast year 2035 with the No Project Alternative levels
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-56
of service at the study intersections are shown in Table V-27. Measured as a function of
intersection delay, the No Project Alternative is modestly (2.9%) superior to the Preferred
Alternative and superior to both Alternatives 1 and 2.
Alternative 1
Upon build out of Alternative 1, total a.m. peak hour volumes at the study intersections are
forecast to be approximately 2% lower than in the Preferred Alternative. The Alternative 1 total
p.m. peak hour volumes are forecast to be approximately 1% lower than the Preferred
Alternative. The total a.m. peak hour delay at the study intersections in Alternative 1 is forecast
to be approximately 4% lower than the Preferred Alternative. The total p.m. peak hour delay at
the study intersections in Alternative 1 is forecast to be approximately 2% lower than the
Alternative, with 4,721.1 seconds of delay during the AM peak and 7,673.2 seconds of delay
during the PM peak. Detailed forecast year 2035 with Alternative 1 levels of service at the study
intersections are shown in Table V-28. below. Measured as a function of intersection delay,
Alternative 1 is modestly (1.6%) superior to the Preferred Alternative, inferior to the No Project
Alternative and superior to Alternative 2.
Alternative 2
Upon build out of Alternative 2 total a.m. and p.m. peak hour volumes at the study intersections
are both forecast to be approximately 1% higher than the Preferred Alternative. The total a.m.
peak hour delay at the study intersections in Alternative 2 is forecast to be approximately 3%
higher than the Preferred Alternative. The total p.m. peak hour delay in Alternative 2 is forecast
to be approximately 1% higher than the Preferred Alternative, with 5,045.4 seconds of delay
during the AM peak and 7,907.9 during the PM peak. Detailed forecast year 2035 with
Alternative 2 levels of service at the study intersections are shown in Table V-29. below.
Measured as a function of intersection delay, Alternative 2 is modestly (1.3%) inferior to the
Preferred Alternative, and inferior to the No Project Alternative and Alternative 1.
Alternatives Impact Summary
The analysis of overall intersection delays is an effective measure of the relative environmental
superiority or inferiority of the various land use alternatives analyzed. As is evident from the
above analysis, the project alternatives vary by less that 4% and less in most cases. While the No
Project Alternative is superior to the others, this alternative does not achieve the goals and
objectives of the project as well as the Preferred Alternative. In all cases, impacts associated with
traffic would be significant and unavoidable.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-57
Table V-27
No Project Alternative Forecast Year 2035 Peak Season
With Adopted General Plan Network Modified * Peak Hour Intersection LOS
Intersection Traffic
Control
AM Peak Hour PM Peak Hour
LOS Delay
(Sec) V/C LOS Delay
(Sec) V/C
1. Washington St & Fred Waring Dr Signal F 95.7 1.181 F 160.2 1.456
2. Washington St & Miles Ave Signal D 43.3 0.964 F 111.9 1.264
3. Washington St & Channel Dr Signal B 13.3 0.677 C 24.2 0.876
4. Washington St & Hwy 111 Signal F 89.0 1.161 F 159.4 1.405
5. Washington St & Ave 48 Signal F 92.1 1.160 D 50.1 1.037
6. Washington St & Eisenhower Dr Signal D 37.1 0.860 D 36.9 0.882
7. Washington St & Ave 50 Signal F 84.1 1.048 F 204.0 1.411
8. Washington St & Calle Tampico Signal B 19.7 0.522 C 23.1 0.527
9. Washington St & Ave 52 Signal F 110.1 1.160 F 99.8 1.111
10. Eisenhower Dr & Calle Tampico Signal C 22.5 0.385 C 24.5 0.440
11. Avenida Bermudas & Ave 52 Signal C 26.8 0.679 C 26.9 0.223
12. Adams St & Fred Waring Dr Signal D 47.0 0.988 E 78.3 1.125
13. Adams St & Miles Ave Signal C 33.8 0.724 E 73.8 1.071
14. Adams St & Hwy 111 Signal C 33.1 0.731 D 37.9 0.886
15. Adams St & Ave 48 Signal D 44.5 0.884 E 64.5 1.009
16. Dune Palms Rd & Fred Waring Dr Signal C 28.0 0.741 F 85.5 1.178
17. Dune Palms Rd & Miles Ave Signal D 35.7 0.710 D 49.3 0.947
18. Dune Palms Rd & Westward Ho Dr Signal C 31.1 0.706 D 40.8 0.936
19. Dune Palms Rd & Hwy 111 Signal C 32.0 0.642 D 45.5 0.970
20. Dune Palms Rd & Ave 48 Signal D 38.0 0.826 E 59.1 1.024
21. Jefferson St & Fred Waring Dr Signal D 37.7 0.857 E 56.8 1.070
22. Jefferson St & Hwy 111 Signal D 36.0 0.818 F 89.7 1.120
23. Jefferson St & Ave 48 Signal D 52.0 0.995 F 86.8 1.170
24. Jefferson St & Ave 49 Signal B 18.1 0.613 B 16.4 0.693
25. Jefferson St & Ave 50 Signal D 51.0 0.995 F 107.3 1.261
26. Jefferson St & Ave 52 Roundabout B 14.4 - F 153.5 -
27. Jefferson St & Ave 54 AWSC F 385.0 2.262 F 570.7 2.690
28. Madison St & Ave 50 AWSC F 454.5 2.497 F 732.1 3.231
29. Madison St & Ave 52 AWSC F 382.3 2.313 F 580.8 2.821
30. Madison St & Ave 54 AWSC F 513.0 3.475 F 747.5 4.778
31. Madison St & Ave 58 AWSC F 289.7 1.936 F 569.2 2.787
32. Madison St & Ave 60 AWSC F 158.1 1.492 F 290.6 1.976
33. Monroe St & Ave 52 AWSC F 336.5 2.052 F 582.6 2.703
34. Monroe St & Ave 54 AWSC F 442.0 2.563 F 628.1 3.024
35. Monroe St & Ave 58 AWSC F 261.4 1.957 F 437.0 2.432
36. Monroe St & Ave 60 AWSC F 82.0 1.224 F 310.2 1.861
37. Monroe St & Ave 62 AWSC D 31.6 0.880 F 156.8 1.435
Total Delay (sec) 4,502.2 7,571.8
Notes:
HCM 2000 Operations Methodology; AWSC = All-way Stop-controlled. BOLD indicates unsatisfactory level of service.
LOS = Level of Service, Delay = Average Vehicle Delay (Seconds), V/C = Volume-to-Capacity Ratio.
*Washington Street downgraded to a 6-lane facility from Highway 111 to Avenue 48. No other modifications to the
currently adopted General Plan roadway network were made.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-58
Table V-28
Alternative 1 Forecast Year 2035 Peak Season
With Adopted General Plan Network Modified * Peak Hour Intersection LOS
Intersection Traffic
Control
AM Peak Hour PM Peak Hour
LOS Delay
(Sec) V/C LOS Delay
(Sec) V/C
1. Washington St & Fred Waring Dr Signal F 98.5 1.202 F 160.4 1.445
2. Washington St & Miles Ave Signal D 44.8 0.972 F 104.7 1.239
3. Washington St & Channel Dr Signal B 13.3 0.677 C 24.2 0.877
4. Washington St & Hwy 111 Signal F 88.5 1.149 F 163.5 1.409
5. Washington St & Ave 48 Signal F 88.9 1.150 D 54.2 1.050
6. Washington St & Eisenhower Dr Signal D 35.8 0.851 D 35.3 0.871
7. Washington St & Ave 50 Signal E 76.8 1.026 F 229.7 1.476
8. Washington St & Calle Tampico Signal B 19.7 0.526 C 23.2 0.513
9. Washington St & Ave 52 Signal F 113.9 1.168 F 96.2 1.093
10. Eisenhower Dr & Calle Tampico Signal C 22.5 0.383 C 24.7 0.436
11. Avenida Bermudas & Ave 52 Signal C 26.4 0.679 C 26.9 0.221
12. Adams St & Fred Waring Dr Signal D 47.5 1.006 F 83.8 1.140
13. Adams St & Miles Ave Signal C 34.1 0.729 F 82.1 1.110
14. Adams St & Hwy 111 Signal C 33.1 0.735 D 36.7 0.877
15. Adams St & Ave 48 Signal D 44.1 0.880 D 54.3 0.947
16. Dune Palms Rd & Fred Waring Dr Signal C 28.8 0.816 F 84.4 1.173
17. Dune Palms Rd & Miles Ave Signal D 35.9 0.715 D 46.7 0.925
18. Dune Palms Rd & Westward Ho Dr Signal C 31.4 0.725 D 45.6 0.969
19. Dune Palms Rd & Hwy 111 Signal C 32.1 0.651 D 47.2 0.984
20. Dune Palms Rd & Ave 48 Signal D 37.8 0.824 E 75.6 1.085
21. Jefferson St & Fred Waring Dr Signal D 37.6 0.852 D 50.0 1.016
22. Jefferson St & Hwy 111 Signal D 36.3 0.844 F 90.9 1.132
23. Jefferson St & Ave 48 Signal E 56.1 1.028 F 81.3 1.148
24. Jefferson St & Ave 49 Signal B 17.9 0.634 B 16.1 0.686
25. Jefferson St & Ave 50 Signal D 50.4 0.990 F 101.1 1.228
26. Jefferson St & Ave 52 Roundabout C 18.7 - F 143.6 -
27. Jefferson St & Ave 54 AWSC F 377.9 2.095 F 584 2.786
28. Madison St & Ave 50 AWSC F 456 2.566 F 707.5 3.162
29. Madison St & Ave 52 AWSC F 386.5 2.243 F 559 2.764
30. Madison St & Ave 54 AWSC F 555 3.772 F 717.2 4.572
31. Madison St & Ave 58 AWSC F 316.6 1.839 F 568.9 2.677
32. Madison St & Ave 60 AWSC F 250.5 2.45 F 460.8 3.284
33. Monroe St & Ave 52 AWSC F 345.5 2.012 F 586.7 2.82
34. Monroe St & Ave 54 AWSC F 453.1 2.468 F 615.6 3.005
35. Monroe St & Ave 58 AWSC F 261 1.846 F 437.7 2.552
36. Monroe St & Ave 60 AWSC F 112.4 1.352 F 305.3 1.975
37. Monroe St & Ave 62 AWSC E 35.7 0.907 F 148.1 1.401
Total Delay (sec) 4,721.1 7,673.2
Notes:
HCM 2000 Operations Methodology; AWSC = All-way Stop-controlled. BOLD indicates unsatisfactory level of service.
LOS = Level of Service, Delay = Average Vehicle Delay (Seconds), V/C = Volume-to-Capacity Ratio.
*Washington Street downgraded to a 6-lane facility from Highway 111 to Avenue 48. No other modifications to the
currently adopted General Plan roadway network were made.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-59
Table V-29
Alternative 2 Forecast Year 2035 Peak Season
With Adopted General Plan Network Modified * Peak Hour Intersection LOS
Intersection Traffic
Control
AM Peak Hour PM Peak Hour
LOS Delay
(Sec) V/C LOS Delay
(Sec) V/C
1. Washington St & Fred Waring Dr Signal F 102.0 1.227 F 171.6 1.476
2. Washington St & Miles Ave Signal D 49.2 0.997 F 109.6 1.251
3. Washington St & Channel Dr Signal B 13.3 0.677 C 24.5 0.880
4. Washington St & Hwy 111 Signal F 95.3 1.191 F 161.1 1.410
5. Washington St & Ave 48 Signal F 96.7 1.178 D 50.8 1.040
6. Washington St & Eisenhower Dr Signal D 38.1 0.867 D 37.4 0.887
7. Washington St & Ave 50 Signal F 86.2 1.060 F 202.9 1.408
8. Washington St & Calle Tampico Signal B 19.4 0.530 C 22.9 0.523
9. Washington St & Ave 52 Signal F 131.7 1.220 F 101.4 1.106
10. Eisenhower Dr & Calle Tampico Signal C 22.6 0.386 C 24.6 0.439
11. Avenida Bermudas & Ave 52 Signal C 26.0 0.678 C 26.9 0.221
12. Adams St & Fred Waring Dr Signal D 50.8 1.043 F 83.0 1.141
13. Adams St & Miles Ave Signal C 35.0 0.746 E 75.7 1.077
14. Adams St & Hwy 111 Signal C 33.6 0.750 D 38.0 0.888
15. Adams St & Ave 48 Signal D 48.1 0.909 E 63.2 1.005
16. Dune Palms Rd & Fred Waring Dr Signal C 29.7 0.839 F 97.2 1.223
17. Dune Palms Rd & Miles Ave Signal D 36.5 0.733 D 51.5 0.964
18. Dune Palms Rd & Westward Ho Dr Signal C 32.1 0.748 D 44.0 0.962
19. Dune Palms Rd & Hwy 111 Signal C 32.5 0.659 D 45.1 0.962
20. Dune Palms Rd & Ave 48 Signal D 39.8 0.844 E 64.1 1.048
21. Jefferson St & Fred Waring Dr Signal D 38.9 0.886 E 66.9 1.129
22. Jefferson St & Hwy 111 Signal D 36.7 0.847 F 93.0 1.161
23. Jefferson St & Ave 48 Signal E 64.0 1.075 F 96.6 1.219
24. Jefferson St & Ave 49 Signal B 17.8 0.654 B 16.4 0.700
25. Jefferson St & Ave 50 Signal E 56.1 1.028 F 112.1 1.276
26. Jefferson St & Ave 52 Roundabout D 29.3 - F 156.7 -
27. Jefferson St & Ave 54 AWSC F 405.1 2.166 F 577.2 2.635
28. Madison St & Ave 50 AWSC F 485.3 2.664 F 760.4 3.203
29. Madison St & Ave 52 AWSC F 424.4 2.346 F 579.8 2.818
30. Madison St & Ave 54 AWSC F 588.1 3.908 F 747.4 4.793
31. Madison St & Ave 58 AWSC F 339.9 1.942 F 590.7 2.719
32. Madison St & Ave 60 AWSC F 259.8 2.467 F 475.2 3.379
33. Monroe St & Ave 52 AWSC F 375.7 2.097 F 585.6 2.714
34. Monroe St & Ave 54 AWSC F 488.1 2.579 F 635 3.033
35. Monroe St & Ave 58 AWSC F 258.5 1.81 F 429.1 2.529
36. Monroe St & Ave 60 AWSC F 127.2 1.439 F 335.3 2.015
37. Monroe St & Ave 62 AWSC D 31.9 0.863 F 155 1.391
Total Delay (sec) 5,045.4 7,907.9
Notes:
HCM 2000 Operations Methodology; AWSC = All-way Stop-controlled. BOLD indicates unsatisfactory level of service.
LOS = Level of Service, Delay = Average Vehicle Delay (Seconds), V/C = Volume-to-Capacity Ratio.
*Washington Street downgraded to a 6-lane facility from Highway 111 to Avenue 48. No other modifications to the currently adopted
General Plan roadway network were made.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-60
P. Water Resources & Quality
Section III-P of this EIR analyzes potential impacts to water resources and water quality that
may arise from implementation of the La Quinta General Plan. As described therein, adherence
to regional, state, and federal standards and regulation as well as the implementation of
mitigation measures, impacts to water resources and quality will be reduced to levels below
significance. Implementation of the proposed General Plan Update will not violate any water
quality standards or waste discharge requirements, and will not substantially deplete groundwater
supplies or interfere with recharge. Sections III-H and V-H, hydrology, further address water
resources as they relate to drainage and stormwater flows.
As described in Section III-P, build out of the Preferred Alternative is projected to generate a
water demand of 37,783 acre-feet within City limits and 16,684 acre-feet within the Sphere. As
such, the entire Planning Area is projected to generate a build out water demand of 54,467 acre-
feet per year under the Preferred Alternative. At build out of the Preferred Alternative, land uses
within City limits will generate an annual water demand of 0.47 acre-feet per person, or
approximately 420 gallons per capita per day (gpcd), and land uses within the Sphere will
generate approximately 0.31 acre-feet per year per person, or 277 gallons per day per capita. To
estimate the water demand generated by each of the Alternatives, a water demand factor for each
land use type by unit, square feet, or acreage was derived from Appendix A of the Water Supply
Study and applied accordingly to each land use type set forth under each Alternative. Detailed
calculations to estimate the water demand generated by each Alternative is provided below.
No Project Alternative
Impacts to water resources and water quality under the No Project Alternative will be similar to
the Preferred Alternative. Within City limits, the No Project Alternative proposes an additional
327 dwelling units and an additional 481,479 square feet of commercial relative to what is
proposed under the Preferred Alternative. As such, there is the potential for slightly more
impacts to water resources and quality under the No Project Alternative within City limits. The
Sphere for the No Project Alternative proposes 9,555 fewer dwelling units and an additional 2.4
million square feet of commercial relative to what is proposed under the Preferred Alternative.
As such, there is the potential for slightly less impacts to water resources and quality under the
No Project Alternative within the Sphere. Mitigation measures and adherence to water quality
standards and regulation will assure that impacts are reduced to less than significant impacts.
As seen in the Table below, the No Project Alternative is projected to generate an annual water
demand of 37,770 acre-feet at build out within City limits and 8,416 acre-feet within the Sphere.
This equates to a per capita water demand of 0.47 acre-feet (420 gpcd) within City limits and
0.28 acre-feet (250 gpcd) within the Sphere. As proposed, the No Project Alternative will
generate a water demand that is comparable to what is projected for the City limits and half of
what is projected for the Sphere relative to the Preferred Alternative.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-61
Table V-30
No Project Alternative Water Demand
Landscaping
(Acre-feet)
Potable
(Acre-feet)
Total Water
Demand
(Acre-feet)
City Limits
Low Density Residential 9,549 5,040 14,588
Medium/High Density Residential 1,398 946 2,345
Commercial 521 1,426 1,947
Major Community Facilities 218 68 286
Open Space - Natural N/A N/A N/A
Open Space- Recreation 18,971 N/A 17,682
Streets, Sidewalks, Medians 922 N/A 922
City Limit Total 37,770
Sphere
Low Density Residential 4,799 1,324 6,123
Medium/High Density Residential 406 577 983
Commercial/Industrial 297.90 582.74 881
Major Community Facilities 74.53 31.29 106
Streets, Sidewalks, Medians 324.17 N/A 324
Sphere Total 8,416
Planning Area
Low Density Residential 14,348 6,363 20,711
Medium/High Density Residential 1,804 1,523 3,327
Commercial/Industrial 819 2,009 2,827
Major Community Facilities 292 100 392
Open Space - Natural N/A N/A N/A
Open Space- Recreation 18,971 N/A 17,682
Streets, Sidewalks, Medians 1,247 N/A 1,247
Planning Area Total 46,186
Alternative 1
Impacts to water resources and water quality under Alternative 1 will be similar to the Preferred
Alternative. Within City limits, Alternative 1 proposes 172 fewer dwelling units and a reduction
of 456,491 square feet of commercial relative to what is proposed under the Preferred
Alternative. As such, slightly decreased impacts to water resources and quality are expected to
occur under Alternative 1 within City limits.
The Sphere for Alternative 1 proposes 10,167 fewer dwelling units and a reduction of 708,498
square feet of commercial relative to what is proposed under the Preferred Alternative.
Therefore, there is the potential for slightly less impacts to water resources and quality under
Alternative 1 within the Sphere. Mitigation measures and adherence to water quality standards
and regulation will assure that impacts are reduced to less than significant impacts.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-62
The table below shows the projected water demand that will be generated at build out of
Alternative 1. Within City limits, the annual water demand is projected to be 37,578 acre-feet,
which is comparable to the water demands generated by the Preferred Alternative. Within the
Sphere the annual water demand under Alternative 1 is projected to be 9,183 acre-feet per year,
which is 45% less than what is projected under the Preferred Alternative. Water demands of
Alternative 1 are projected to generate a per capita water demand of 0.47 acre-feet per year (420
gpcd) for City limits and 0.32 acre-feet per year (282 gpcd) for the Sphere.
Table V-31
Alternative 1 Water Demand
Landscaping
(Acre-feet)
Potable
(Acre-feet)
Total Water
Demand
(Acre-feet)
City Limits
Low Density Residential 9,127 4,817 13,944
Medium/High Density Residential 1,572 1,064 2,637
Commercial 472 1,294 1,766
Major Community Facilities 477 150 626
Open Space - Natural N/A N/A N/A
Open Space- Recreation 17,682 N/A 17,682
Streets, Sidewalks, Medians 922 N/A 922
City Limit Total 37,578
Sphere
Low Density Residential 6,544 1,805 8,349
Medium/High Density Residential 6 8 13
Commercial/Industrial 152 298 450
Major Community Facilities 32 14 46
Streets, Sidewalks, Medians 324 N/A 324
Sphere Total 9,183
Planning Area
Low Density Residential 15,671 6,622 22,294
Medium/High Density Residential 1,578 1,072 2,650
Commercial/Industrial 624 1,591 2,216
Major Community Facilities 509 163 673
Open Space - Natural N/A N/A N/A
Open Space- Recreation 17,682 N/A 17,682
Streets, Sidewalks, Medians 1,247 N/A 1,247
Planning Area Total 46,760
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-63
Alternative 2
Impacts to water resources and water quality under Alternative 2 will be similar to the Preferred
Alternative. Within City limits, Alternative 2 proposes 300 additional dwelling units and an
addition of 14,915 square feet of commercial relative to what is proposed under the Preferred
Alternative. As such, slightly greater impacts to water resources and quality are expected to
occur under Alternative 2 within City limits.
The Sphere for Alternative 2 proposes 3,655 additional dwelling units and an additional 363,280
square feet of commercial relative to what is proposed under the Preferred Alternative.
Therefore, there is the potential for slightly greater impacts to water resources and quality under
Alternative 2 within the Sphere. Mitigation measures and adherence to water quality standards
and regulation will assure that impacts are reduced to less than significant impacts.
As seen in the Table below, Alternative 2 is projected to generate an annual water demand of
37,919 acre-feet at build out within City limits and 16,846 acre-feet within the Sphere. This
equates to a per capita water demand of 0.47 acre-feet (420 gpcd) within City limits and 0.27
acre-feet (241 gpcd) within the Sphere. As proposed, Alternative 2 will generate a water demand
that is comparable to what is projected under the Preferred Alternative for City limits and the
Sphere.
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-64
Table V-32
Alternative 2 Water Demand
Landscaping
(Acre-feet)
Potable
(Acre-feet)
Total Demand
(Acre-feet)
City Limits
Low Density Residential 9,268 4,892 14,160
Medium/High Density Residential 1,593 1,078 2,671
Commercial 497 1,360 1,857
Major Community Facilities 477 150 626
Open Space - Natural N/A N/A N/A
Open Space- Recreation 17,684 N/A 17,682
Streets, Sidewalks, Medians 922 N/A 922
City Limit Total 37,919
Sphere
Low Density Residential 11,186 3,086 14,272
Medium/High Density Residential 649 922 1,571
Commercial/Industrial 214 419 632
Major Community Facilities 32 14 46
Streets, Sidewalks, Medians 324 N/A 324
Sphere Total 16,846
Planning Area
Low Density Residential 20,455 7,977 28,432
Medium/High Density Residential 2,242 2,000 4,242
Commercial/Industrial 711 1,779 2,489
Major Community Facilities 509 163 673
Open Space - Natural N/A N/A N/A
Open Space- Recreation 17,684 N/A 17,682
Streets, Sidewalks, Medians 1,247 N/A 1,247
Planning Area Total 54,764
Environmentally Superior Alternative E.
CEQA requires that the analysis of alternatives include a conclusion as to which alternative is
environmentally superior. Based on the analysis in this Section of the EIR, and when compared
to that provided in Section III, all the alternatives will have similar impacts on aesthetics,
agricultural resources, biological resources, cultural resources, geology and soils, and hydrology.
Impacts associated with issue areas directly tied to development, including air quality, noise,
public facilities, water resources and traffic, will be lower under the No Project Alternative and
Alternative 1, and equal or higher under the Alternative 2.
For air quality impacts, where the impacts have been determined to remain significant and
unavoidable under the Preferred Alternative, even after the implementation of all feasible
mitigation measures, none of the alternatives would reduce all these impacts to less than
significant levels. The No Project (2002 General Plan) alternative, would have the least
Terra Nova/La Quinta General Plan EIR
Section V. Project Alternatives
V-65
significant amount of emissions, but would still have significant impacts to air quality. As
regards GHG impacts, the No Project alternative has the greatest potential for impacts, since it is
the only alternative where the City’s Greenhouse Gas Reduction Plan would not be implemented,
since annexation would not occur. All other alternatives would reduce GHG impacts to less than
significant levels with implementation of the Greenhouse Gas Reduction Plan.
Traffic impacts remain significant and unavoidable under the Preferred Alternative. Traffic
impacts associated with all the alternatives would result in significant and unavoidable impacts
under all alternatives, although the No Project Alternative would be marginally better than the
others.
In the overall, the No Project Alternative would have lesser impacts on the environment, and
would represent the environmentally superior alternative. The No Project Alternative can be
considered in this case, because it would result in development under the 2002 General Plans of
the City and the County, and is not a No Project/No Development alternative.
However, the General Plan Update was undertaken because the 2002 General Plan no longer
meets the community’s needs and goals. Therefore, the No Project Alternative would no meet
the Project Objectives established in this Section. Alternative 1 would be the next most superior
alternative.
Terra Nova/La Quinta General Plan EIR
Section VI. Short-Term Use Versus Long-Term Productivity
VI-1
LA QUINTA GENERAL PLAN
ENVIRONMENTAL IMPACT REPORT
VI. SHORT-TERM USE VERSUS LONG-TERM PRODUCTIVITY
Introduction
This section of the EIR weighs the proposed short-term uses of the environment relative to the
maintenance and enhancement of long-term productivity and justifies adoption and
implementation of the La Quinta General Plan Update. The focus is on areas of impact that
ultimately limit the range of beneficial uses of the environment, pose long-term health and safety
risks, or result in long-term impacts to nonrenewable resources. Areas of concern include
agricultural resources, biological resources, air and water resources, geophysical conditions, and
visual resources.
Agricultural Resources
Land use designations within the City do not provide for agricultural activities. The adoption of
the General Plan Update will have no immediate effect on agricultural resources. Implementation
of the General Plan Update will, however, result in the long term removal of agricultural
resources from the Planning Area. The General Plan Update allows for the increased urban
development through the intensification of residential and commercial development, and to a
lesser degree, industrial development within the Sphere of Influence.
Undeveloped portions the Sphere are located in areas designated as Prime Farmland, Farmland
of Statewide Importance, Unique Farmland or Lands of Statewide Importance, according to the
Riverside County Important Farmland Map of 2008. In 2008, there were approximately 1,700
acres of important agricultural land located in the City, and 7,391 acres in the Sphere of
Influence, for a total of 9,091 acres. The lands within the City have been designated for urban
uses for many years, and are not in agriculture currently. Some of the 7,391 acres in the Sphere
are currently being farmed, and some are vacant desert, or have been developed for residential
uses.
There are currently over 545,000 acres of important farmland in Riverside County1. The 7,391
acres of land designated as important farmland represents 1.3% of the total important farmland in
the County. The eventual loss of these lands will not significantly impact agriculture in the
region.
1 California Department of Conservation, Division of Land Resource Protection. 2008-2010 Land Use Conversion
inventory.
Terra Nova/La Quinta General Plan EIR
Section VI. Short-Term Use Versus Long-Term Productivity
VI-2
Biological Resources
Implementation of the La Quinta General Plan Update will facilitate growth and development
throughout the Planning Area, which will affect biological resources in the short term and
degrade the long-term productivity of natural communities. Construction activities, including
grubbing, clearing, grading, paving, and building development, as well as increased operational
use, will result in the degradation and loss of natural habitat, thereby impacting natural
communities. Furthermore, the introduction of non-native and invasive species associated with
development and urbanization could substantially alter the desert environment.
As discussed in Section III, the General Plan Update has the potential to impact state or federal
listed threatened or endangered species, or special status species including two plant species,
Glandular Ditaxis and California Ditaxis (Ditaxis serrata var. californica), the Coachella Valley
Fringe-Toed Lizard, Desert tortoise, Le Conte’s Thrasher, Burrowing Owl, and Peninsular
Bighorn Sheep. That being said, the General Plan Update does include a natural open space land
use designation that will preserve undisturbed lands within the Planning Area. Furthermore, the
General Plan Update is consistent with the regional habitat conservation plan.
The Coachella Valley Multiple Species Habitat Conservation Plan (MSHCP) sets forth the
preservation of lands for long term management and monitoring. The MSHCP allows for the
incidental take of listed species for specific covered activities and assures protection of important
habitat. The MSHCP identifies critical habitat throughout the Coachella Valley, including the
Santa Rosa and San Jacinto Mountains Conservation Area.
The General Plan Update includes goals, policies and programs that are consistent with the
MSHCP and assures protection the Santa Rosa and San Jacinto Mountains Conservation Area.
Increased development and urbanization within the Planning Area will contribute to the
reduction of natural habitat and associated biological resources. The La Quinta General Plan
Update provides designated open space lands that will be preserved in perpetuity, and limits
densities and allowable land uses in proximity to Conservation Areas. The General Plan Update
is consistent with the MSHCP and will facilitate the protection of sensitive species in areas
designated as critical and sensitive habitat. Although the General Plan Update will result in short
term impacts in the form of incidental take, habitat degradation, and land conversion, the long-
term goals of habitat preservation, species protection, and connectivity are achieved by
complying with the MSHCP.
Air Quality
Air quality is a regional concern caused by increased urban development, industry, and vehicular
traffic. The Planning Area is located within the Salton Sea Air Basin (SSAB) and is managed by
the South Coast Air Quality Management District (SCAQMD). As development within the
SSAB continues, new sources of air quality emissions will result from a variety of activities
including grading and construction, increased vehicle emissions from traffic, and increased usage
of natural gas and electricity for operation of buildings and facilities, and other anthropogenic
sources. Air emissions from outside the SSAB, including the neighboring South Coast Air Basin
to the west, also continue to contribute to air quality conditions within the SSAB.
Terra Nova/La Quinta General Plan EIR
Section VI. Short-Term Use Versus Long-Term Productivity
VI-3
The General Plan Update will facilitate urban development throughout the Planning Area,
thereby contributing to increased air quality emissions throughout the SSAB. Existing vacant and
agricultural land, particularly within the Sphere of Influence, will transition to urban uses,
thereby increasing emissions from construction activities, energy use, and traffic. Construction
activities will result in elevated levels of NOx and ROG’s from off-road equipment, and will
increase the amount of particulate matter during grading and site disturbance. Increased
vehicular traffic will also result in elevated levels of carbon monoxide, NOx, ROG’s, and
particulate matter from ongoing operation. In the short-term, emissions levels and impacts to air
quality will continue to rise until new transportation methods, development standards, and
combustion technology develop.
The General Plan Update provides goals, policies, and programs to reduce and mitigate against
criteria pollutants and greenhouse gas emissions. In addition, the City has prepared a GHG
Reduction Plan to reduce GHG emissions to levels that are consistent with Assembly Bill 32.
Long term productivity of air quality resources are expected to be preserved through successful
implementation of the GHG Reduction Plan.
Water Resources
As discussed in Section III of this EIR, the Coachella Valley Water District (CVWD) provides
water services in to the La Quinta Planning Area. Domestic water supplies are produced from
groundwater extracted from the Whitewater River Subbasin. Implementation of the General Plan
Update is expected to increase water demand by approximately 22,000 acre-feet per year at build
out. CVWD’s service area, including the La Quinta Planning Area, is expected to continue to
generate a growing demand for water. Through conjunctive use management, conservation, and
other strategies CVWD expects to have sufficient water supplies to serve the General Plan
Update Planning Area and surrounding region through 2035 and beyond, including during
normal, single, and multiple dry year conditions.
The proposed General Plan Updates includes policies and programs intended to promote and
support the conservative use of water resources including requiring water efficient appliances,
advanced irrigation control for outdoor landscaping, and the use of drought tolerant planting
materials. In addition, CVWD is expanding recycled water supplies and provides large scale
irrigator, such as golf courses with reclaimed water in lieu of groundwater for irrigation
purposes. Although these and other water resources programs conserve water and reduce
groundwater extraction in the short term, factors, such as periodic drought conditions in
California, and the potential for reduced Colorado River imports, continue to affect the
availability of domestic water resources for future development. As such, continued growth in
the Valley, including implementation of the General Plan update in combination with drought
years, could potentially impact water resources and compromise the long term productivity of
groundwater supplies.
Terra Nova/La Quinta General Plan EIR
Section VII. Irreversible and Irretrievable Commitment of Environmental Resources
VII-1
LA QUINTA GENERAL PLAN
ENVIRONMENTAL IMPACT REPORT
VII. IRREVERSIBLE AND IRRETRIEVABLE COMMITMENT OF
ENVIRONMENTAL RESOURCES
Pursuant to CEQA Section 15126.2(c), the following discussion addresses the potentially
significant irreversible changes or irretrievable commitment of non-renewable resources that
could occur from implementation of the General Plan Update. In general non-renewable
resources imply energy resources, but may also pertain to the permanent loss of biological,
mineral and other natural resources. The use of non-renewable resources during short-term
construction and long-term operation of the Planning Area may be irreversible and irretrievable.
The growth and development facilitated by the proposed General Plan Update will result in the
irretrievable and irreversible commitment of renewable and non-renewable natural resources,
including open land, biological and energy resources (i.e., oil, natural gas, petroleum, coal, etc.),
water resources, mineral resources, and construction materials such as lumber, gravel, sand,
asphalt, and metals.
As the Planning Area continues to build out as a result of implementation of the General Plan
Update, environmental resources will be irretrievably lost. Undisturbed habitat, open space and
other biological will be committed to urban land uses. Most notably, new residential subdivisions
and commercial centers will be developed on vacant land within the Sphere of Influence.
New growth and development throughout the Planning Area will increase consumption of
electricity, natural gas, and petroleum fuels. Mineral resources will also be consumed in the
construction of buildings, roads, and facilities across the Planning Area. Local quarries in the
Coachella Valley provide aggregate, sand and gravel, and crushed stone used for the construction
of roads, sidewalks and hardscape, as well as plaster used for building facades. Increased
construction facilitated by the General Plan Update will contribute to the irretrievable
commitment of these resources.
The General Plan Update establishes the regulatory framework and proposes land use intensities
and densities that are intended to preserve and protect valuable resources and reduce long-term
impacts to environmental resources. Furthermore, the Plan is consistent with the Coachella
Valley MSHCP and prohibits development within the MSHCP Conservation Areas.
Terra Nova/La Quinta General Plan EIR
Section VII. Irreversible and Irretrievable Commitment of Environmental Resources
VII-2
The General Plan Update provides goals, policies and programs intended to conserve and protect
valuable resources and substantially reduce long-term impacts. The Sustainable Community
Element identifies the approach to reduce the Planning Area’s irreversible or irretrievable use of
non-renewable resources, thereby limiting air quality emissions and water pollution. The
Greenhouse Gas Reduction Plan also provides strategies for reducing greenhouse gas emissions
and achieving reduction targets consistent with state goals as set forth in AB32.
This EIR sets forth mitigation measures, the implementation of which will reduce potential
impacts associated with the proposed General Plan to less than significant levels for non-
renewable environmental resources.
Finally, outside influences, such as the development of new and more efficient technologies are
anticipated to reduce impacts on fossil fuel resources and other finite mineral resources. These
efforts will minimize the irreversible or irretrievable loss of environmental resources, even as
growth continues.
Terra Nova/La Quinta General Plan EIR
Section VIII. Growth Inducement
VIII-1
LA QUINTA GENERAL PLAN
ENVIRONMENTAL IMPACT REPORT
VIII. GROWTH INDUCEMENT AND CUMULATIVE IMPACTS
The CEQA Guidelines, Section 15126.2(d) state that growth-inducing impacts include projects
that foster economic or population growth, or the construction of housing, either directly or
indirectly, in the surrounding environment. Increased population may create impacts to existing
community facilities or require the construction of new facilities that could cause significant
environmental effects. This section discusses growth-inducing impacts caused by the La Quinta
General Plan Update, and how these impacts may encourage and facilitate other activities that
could cumulatively affect the environment, or induce growth.
Growth Inducement A.
Adoption of the La Quinta General Plan Update will not directly induce growth. Rather,
implementation of the General Plan through future development could be growth inducing.
Although the General Plan Update will not result in any construction project, it facilitates
development, thereby inducing growth. The General Plan Update will induce growth through
implementation of the proposed land use designations and densities, the development of new and
widened roadways, and the expansion of infrastructure.
The General Plan will allow for growth and development on lands currently governed by the
2002 La Quinta Comprehensive General Plan and the Riverside County General Plan. The
proposed La Quinta General Plan Update allows for approximately 8,114 new residential units,
including 4,751 Low Density Residential and 3,362 Medium/High Density Residential units on
vacant or un-developed lands throughout the City. This could support an estimated 20,528
people, assuming an average household occupancy of 2.53. As discussed in Section III, however,
this increase is less than projected by the existing 2002 General Plan, and consistent with SCAG
forecasts for growth in the City. As such, the General Plan Update is not expected to result in
significant growth inducing impacts within City limits.
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Section VIII. Growth Inducement
VIII-2
The General Plan Update allows for the development of up to 20,699 residential dwelling units,
including 20,480 Low Density Residential and 219 Medium/High Density Residential on lands
that are currently vacant or used for agricultural production within the Sphere of Influence. The
vase majority of these units will occur in the eastern Sphere. These units would result in a build
out population size of 52,368 within the Sphere at 100% occupancy. In comparison, were the
Sphere of Influence to build out under the current County land use designations, a total of 11,946
residential units would be developed. This would yield a population of 30,222. Implementation
of the General Plan Update would increase the population within the Sphere of Influence by
22,146 people. Therefore, the General Plan Update has the potential to induce growth and result
in a substantial increase to the population size within the Sphere of Influence.
Lands in the eastern Sphere will continue to develop at densities assigned by the County General
Plan. Only if the lands are annexed would the City’s General Plan be applied to these lands. The
General Plan includes a requirement for master planning of the eastern Sphere, to address the
land use distribution and allocation in the Vista Santa Rosa area. This master plan is to be
undertaken prior to annexation of this area, to give future projects clear direction on the
character, intensity and density of the area. The master plan may result in reduced densities and
land use intensities, which will lower the ultimate number of units possible in this area, should it
be annexed. Such a reduction would also reduce the ultimate population of the area.
The development of new commercial and industrial lands facilitated by the General Plan Update
will increase the number of jobs available within the Planning Area. The General Plan Update
proposes new commercial and industrial lands within the City limits and the Sphere of Influence.
Overall, the proposed General Plan allows for approximately 5,676,835 square feet of new
commercial square footage, 3,218,039 square feet of which will occur within the City limits and
2,458,797 square feet within the Sphere of Influence. This is slightly less than anticipated by the
2002 General Plan and the Riverside County Vista Santa Rosa land use plan. The General Plan
Update also calls for 611,408 square feet of industrial lands within the Sphere of Influence. The
Vista Santa Rosa Plan does not include any industrial land use designation. The commercial and
industrial lands proposed within the Planning Area as part of the General Plan Update have the
potential to induce growth by attracting employees to these commercial and industrial projects,
and therefore increasing the demand for housing. As most commercial development results from
an increase in residential units, it is likely that much of the potential employee pool will occupy
the new units created by implementation of the General Plan.
New construction in the City and Sphere will also likely spur demand for construction and
landscape contractors. It is anticipated that local contractors residing in the Coachella Valley will
benefit from these activities, particularly since construction of projects will occur over time, not
all at once.
An existing roadway network currently serves the General Plan Update Planning Area, including
areas within the Sphere of Influence. This roadway network is well developed in the City, but
will need expansion (widening and additional traffic control) in the Sphere of Influence. New
roadways developed throughout the Planning Area will primarily be internal to developing
properties, such as new local streets within new residential subdivisions. Improvements to major
arterials and collectors will occur as development occurs, and through capital improvement
Terra Nova/La Quinta General Plan EIR
Section VIII. Growth Inducement
VIII-3
programs implemented by the City and County. Appropriate phasing of roadway improvements
will ensure optimal expansion and efficient development of roadways.
As described above, the new commercial and industrial development proposed by the General
Plan Update has the potential to increase the number of jobs available to City residents. This
increase in employment opportunities may reduce the trip length of commuting residents, who
currently travel outside the Planning Area for employment. At the same time, however, new
commercial and industrial development may also result in increased trip lengths for residents
living outside the Planning Area.
The General Plan Update will create growth-inducing impacts from the expansion of
infrastructure, including electric, gas, water, sanitary sewer, and telecommunication services.
The City is well served by existing utilities and infrastructure; however, the Sphere of Influence
will require substantial infrastructure improvements, especially sanitary sewer services. Existing
utility infrastructure will need to be extended to serve future residents in portions of the Planning
Area not currently served by utilities. Service extensions for water and sewer will be required of
development projects in their conditions of approval, and will not occur without these projects.
The bulk of the costs associated with the improvements will be borne by the developers, and not
by the service providers.
Cumulative Impacts B.
As set forth in Section 15130 of the CEQA Guidelines, EIRs are required to discuss cumulative
impacts when a project’s incremental effect is cumulatively considerable, as defined in section
15065(a)(3). Pursuant to Public Resources Code Section 21083 (b), and CEQA Guidelines
Section 15355, a cumulative impact occurs when the incremental effect of an individual project
is considerable when viewed in the context of past, existing, and forthcoming projects. When
viewed in conjunction with development throughout the Coachella Valley, the La Quinta
General Plan Update will result in cumulatively considerable impacts.
Adoption and implementation of the proposed General Plan Update will govern development
patterns and intensity within the City limits, and should annexation occur, within the Sphere of
Influence. The General Plans of the City of Indio, City of Coachella and the County of Riverside
will affect development patterns on lands contiguous to the Planning Area. For the most part, the
General Plans for these surrounding communities will provide similar urban and suburban land
use patterns as the La Quinta General Plan Update.
The Sphere of Influence is located within the Eastern Coachella Valley Area Plan, as designated
by Riverside County. Relative to the La Quinta Planning Area, the City of Palm Desert lies to the
northwest, the City of Indio to the north, the City of Coachella to the northeast, unincorporated
County lands to the east and south, and the City of Indian Wells to the west. Policy constraints
and the need for expanded infrastructure, especially on lands to the east, are expected to have a
moderating influence on permitted development by surrounding jurisdictions.
Terra Nova/La Quinta General Plan EIR
Section VIII. Growth Inducement
VIII-4
The surrounding General Plans, in conjunction with the proposed La Quinta General Plan
Update, will result in cumulatively considerable impacts to Land Use, Geology and Minerals,
Water Resources, Air Quality, and Traffic/Circulation.
Aesthetic/Visual Resources
The La Quinta Planning Area contains important aesthetic resources. The Planning Area is
located in a flat valley surrounded by the dramatic peaks of the Santa Rosa, San Jacinto, and
Little San Bernardino Mountains. These geological features define the community’s character
and enhance the quality of life for residents and visitors. Implementation of the General Plan
Update will facilitate development within the Planning Area. However, no development will be
allowed in the foothills of the Santa Rosa Mountains, located within the western portion of the
Planning Area. The General Plan Update will continue to protect these dramatic backdrops
through open space designations, viewshed and construction restrictions.
The General Plan Update also provides policies and programs that protect important viewsheds
and preserve scenic resources. These include the maintenance of image corridors, integration of
landscaping standards that incorporate the region’s visual character into urban design, as well as
setback and height restrictions that avoid viewshed impediment. As a result, cumulative impacts
to visual resources are expected to be less than significant.
Agricultural Resources
Undeveloped portions the Sphere are located in areas designated as Prime Farmland, Farmland
of Statewide Importance, Unique Farmland or Lands of Statewide Importance, according to the
Riverside County Important Farmland Map of 2008. In 2008, there were approximately 1,700
acres of important agricultural land located in the City, and 7,391 acres in the Sphere of
Influence, for a total of 9,091 acres.
Implementation of the General Plan Update does not require landowners to immediately convert
farmland to new land uses. However, new development proposed will be required to develop
according to new land use designations. As a result, agricultural lands will be affected by new
development.
There are currently over 545,000 acres of important farmland in Riverside County1. The 7,391
acres of land designated as important farmland represents 1.3% of the total important farmland in
the County. The eventual loss of these lands will not cumulatively impact agriculture in the
region.
Land uses within the eastern Sphere of Influence are currently governed by the County’s Vista
Santa Rosa Community Plan, which allows for both residential and agriculture related uses.
These lands will continue under the jurisdiction of the County of Riverside until the completion
of master planning for the area. The General Plan Update requires that the master planning
consider the area’s character. This is likely to include very low intensity development, and
agricultural or ranching uses. Further, the City’s Zoning Ordinance includes an
1 California Department of Conservation, Division of Land Resource Protection. 2008-2010 Land Use Conversion
inventory.
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Section VIII. Growth Inducement
VIII-5
Agricultural/Equestrian Overlay which applies to all lands in the Sphere. This overlay was
specifically designed to allow for the preservation of agricultural and ranching uses in the Sphere
area.
Air Quality
As discussed in Section III, the La Quinta Planning Area is located within the Salton Sea Air
Basin, which is managed by the South Coast Air Quality Management District( SCAQMD. The
Basin is currently designated as a non-attainment area for ozone and particulate matter. The
Planning Area is subject to SCAQMD’s 2007 Air Quality Management Plan, which identifies
strategies and measures to reduce air quality impacts.
A combination of local and regional strategies have been developed and are included within the
General Plan Update in an effort to minimize or reduce air quality impacts. The City of La
Quinta requires best management practices, adherence to building codes and standards, and the
adoption of dust control plans for all new development. Furthermore, the City has prepared a
Greenhouse Gas (GHG) Reduction Plan, as part of this General Plan Update, which identifies
methods and development standards to reduce greenhouse gas emissions. Implementation of
mitigation measures, including adherence to the GHG Reduction Plan is expected to
substantially reduce the emission of air quality pollutants. Therefore, it is expected that with
mitigation measures and successful implementation of the GHG Reduction Plan, the General
Plan Update will have less than significant impacts to air quality.
However, some of the air quality reduction measures are contingent upon factors outside of the
City’s control. While the City is committed to achieving air quality emission reductions,
increasing energy efficiency, and incorporating sustainable development principles, air quality
conditions are affected by regional emissions. Although the General Plan Update is consistent
with the Air Quality Management Plan and impacts to air quality will be minimized within the
Planning Area, surrounding jurisdictions’ build out, in conjunction with the General Plan Update
will result in cumulatively considerable impacts to air quality.
Implementation of the General Plan Update has the potential to impact air quality from grading
and construction activities, vehicle emissions, and daily operations, including the use of natural
gas and electricity for operation of existing and new buildings and structures. Vehicular traffic
emissions are projected to be the greatest source of air pollutants. These increases in air quality
emissions from implementation of the General Plan Update, in combination with new growth
and development within surrounding jurisdictions, has the potential to result in exceedences of
criteria pollutant standards and ozone precursors. As such, the General Plan Update will have
cumulatively considerable impacts to air quality.
Biological Resources
Existing urban development and agricultural uses have eliminated the majority of undisturbed
lands within City. Natural habitat remains on the undevelopable and protected slopes of the
Santa Rosa Mountains. In addition, there are likely pockets of sensitive habitat that remain
within portions of the Planning Area, primarily within the less developed Sphere of Influence.
Implementation of the General Plan Update will facilitate new growth and development on
undeveloped lands that may contain sensitive habitat or species. Increased population growth as
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Section VIII. Growth Inducement
VIII-6
permitted by the General Plan Update and growth expected to occur in surrounding jurisdictions
will increase disturbance on open space lands from human use, vehicle travel, garbage dumping,
and domestic and opportunistic animals. The introduction of non-native plants and animal
species also may create adverse impacts to native species. New growth within the La Quinta
Planning Area, along with development occurring in surrounding jurisdictions will contribute to
the cumulative loss of sensitive habitat and associated species.
The preservation of land through designated open space areas within the Planning Area, and the
Coachella Valley Multiple Species Habitat Conservation Plan will limit any cumulatively
considerable regional disruption of wildlife. Policies and programs in the proposed General Plan
Update include the integration of open space areas and wildlife corridors. Given that sensitive
species currently occur within the planning area, development proposals will be required to
adequately mitigate impacts to wildlife and habitat before development is permitted. The City’s
participation and enforcement of the Multiple Species Habitat Conservation Plan will reduce
cumulative impacts to sensitive species, and its implementation will protect habitats for these
species. These activities will reduce the cumulative impacts to biological resources to less than
significant levels.
Cultural Resources
As discussed in Section III, the La Quinta Planning Area contains culturally sensitive areas.
Based on past cultural surveys, a number of historic and archaeological sites associated with the
Native Americans have been identified within City limits and to a lesser extent in the Sphere of
Influence. The region is known to contain sensitive paleontological resources, including fossil
deposits near the ancient Lake Cahuilla. The potential exists for discovering additional culturally
important sites in the future. New development proposed by the General Plan Update will
potentially result in the disturbance or destruction of cultural resources due to grading, site
excavation, construction, and urbanization.
Policies and programs of the proposed General Plan Update are intended to protect and preserve
cultural resources within the Planning Area. Cultural resource surveys will be required for
proposed projects that have the potential to disturb or destroy sensitive resources. Mitigation
measures proposed in this EIR will also assure protection of cultural resources. As such, no
significant cumulative impacts to cultural resources are expected to result from adoption and
implementation of the proposed General Plan Update.
Geology/Seismicity
The La Quinta General Plan Update Planning Area is subject to potentially moderate to severe
ground shaking as a result of earthquakes along the San Andreas Fault Zone and associated faults
in the surrounding area. Previous seismic events and associated ground motion in the Planning
Area have been known to cause severe damage to the built environment, including structures and
roadways. The Planning Area is also subject to other seismically induced hazards, including
liquefaction, seismically induced settlement, rock falls and landslides. Due to soil type, depth to
groundwater, and other conditions, land within the Planning Area, especially the eastern Sphere
of Influence, have potential to be impacted by liquefaction. Liquefaction can cause buildings to
tilt or sink. Landslide and rock fall hazards exist along the foothills at the western portion of the
Planning Area. The General Plan Update will facilitate continued urbanization, increasing the
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Section VIII. Growth Inducement
VIII-7
number of homes, commercial and industrial buildings susceptible to seismic hazards, thereby
exposing new buildings and structures, as well as an increased number of people, to seismic
related hazards.
New growth and development facilitated by the General Plan Update will be designed in
accordance with policies and programs set forth in the proposed General Plan Update, as well as
mitigation measures in this EIR, which will help minimize geological hazards. New buildings
and facilities will also be developed in accordance with strict seismic requirements of the
Uniform Building Code. New development in surrounding jurisdictions will also be required to
adhere to such building codes. With the implementation of these and other appropriate design
and engineering precautions for future development, no significant cumulative impacts
associated with geotechnical hazards are expected to result from adoption and implementation of
the proposed General Plan Update.
Hydrology
The City of La Quinta is responsible for local flood control facilities and has recently updated its
Master Drainage Plan. The Coachella Valley Water District and the Riverside County Flood
Control and Water Conservation District are responsible for regional drainage facilities.
Implementation of the proposed General Plan Update, as well as build out of surrounding
jurisdictions, will facilitate urban development and increase impervious surfaces throughout the
region. As a result, storm water runoff will increase. The La Quinta General Plan Update
includes goals, policies and programs to ensure that forthcoming development recognizes and
plans for flood hazards, and includes stormwater management facilities, such as on-site
stormwater retention basins. Future development within surrounding jurisdictions will also be
required to address the potential risk of flood hazards and require on-site stormwater retention.
The City and surrounding jurisdictions currently participate in the National Pollutant Discharge
Elimination System (NPDES) program. The NPDES mandates the adoption of stormwater
management plans and programs to reduce runoff of pollutants into Waters of the United States.
As a result, the General Plan Update in conjunction with growth and development of surrounding
jurisdictions will not result in cumulatively considerable impacts to hydrology.
Land Use
The development pattern and intensity of new residential and commercial projects will be
consistent with existing land use designations and densities currently found throughout the City.
Through the thoughtful planning of development sites, and the integration of new projects into
existing neighborhoods, impacts to land use within City will not be cumulatively significant.
Development within the Sphere of Influence will be regulated through a master plan, which will
assure consistency with surrounding development intensities. As proposed, the Sphere of
Influence will develop primarily as low density residential, with associated commercial, and
limited industrial land uses. The intensity of development in the Sphere of Influence, however,
could be significantly different from what currently exists in the area. Build out of the La Quinta
General Plan Update, along with build out of the surrounding jurisdictions’ General Plans
mentioned above, could substantially change the existing character of the region from a rural and
agricultural community to a more urbanized environment. As a result, new growth and
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Section VIII. Growth Inducement
VIII-8
development facilitated by the General Plan Update could create cumulatively significant land
use impacts.
Noise
The primary source of noise throughout the Planning Area is the operation of motor vehicles on
City streets. Land uses adjacent to major arterials therefore experience higher noise levels.
Throughout the Sphere of Influence, noise levels are generally lower due to the rural
environment. Implementation of the General Plan Update will facilitate new growth and
development in the Sphere of Influence and result in the intensification of land use development
within City limits, thereby leading to increased traffic volumes and associated higher noise
levels. In addition, construction equipment noise, and the noise generated by mechanical
equipment will increase as new development and infill development occurs. The ambient noise
level will rise as the General Plan Update is implemented.
The proposed General Plan Update includes a wide range of policies and programs that will
reduce potential noise impacts to less than significant levels. Such policies include adherence to
community noise standards, compliance monitoring, land use compatibility planning, and other
noise reducing strategies. Mitigation measures provided in this EIR will also help reduce impacts
from increased noise levels. Acoustical analyses may be required to properly identify, mitigate
and reduce project-related noise impacts to acceptable levels.
Although cumulative noise levels are expected to rise due to regional growth and development,
implementation of goals, policies and programs set forth in General Plan Update, and mitigation
measures provided in this EIR will sufficiently protect sensitive receptors from noise impacts. As
a result, the General Plan Update is not expected to generate cumulatively considerable noise
impacts.
Public Services and Utilities
Implementation of the General Plan Update will increase the demand for public services and
facilities. As development occurs throughout the Planning Area and region, the incremental and
cumulative increase in population will require additional police and fire protection, school and
library services, parks and recreation facilities, and public and quasi-public utilities, including
electricity, natural gas, water, sanitary sewer and solid waste management.
As growth continues, public services and facilities will incur proportional increases in service
demands. Public utility companies have developed rate structures to provide for the expansion of
facilities as demand continues. Developer impact fees will continue to be required for new
projects of all types. Fees collected are used to offset increased demands to public services and
facilities by funding school expansions, roadway improvements and public buildings. Increased
property tax and sales tax revenue also provide additional funding for new police and fire
services.
The General Plan Update provides policies and programs that accommodate expansion of such
facilities as growth continues. The General Plan Update and Greenhouse Reduction Plan, include
provisions that are intended to realize increased efficiency and conservation, thereby minimizing
Terra Nova/La Quinta General Plan EIR
Section VIII. Growth Inducement
VIII-9
the demand for electricity, natural gas, and water resources, and substantially limiting the City’s
contribution of solid waste to landfills.
In addition to service providers’ plans to accommodate increased demands, the proposed General
Plan provides goals, policies and programs that will minimize cumulative impacts to public
services and facilities. Therefore, cumulative impacts to public services and facilities are
expected to be less than significant.
Traffic/Circulation
The consequences of General Plan build out have been evaluated for the 63 major roadway
segments and 37 intersections. Based on this analysis, the proposed General Plan is projected to
generate a total of approximately 635,905 average daily trips. Of these, 449,489 ADT would be
generated within the City's corporate limits and 186,416 would be generated in the City Sphere-
of-Influence.
Within the City's corporate limits, the proposed Land Use Plan will generate about 3.6% more
traffic than build out of the 2002 General Plan. Within the City's Sphere, the proposed Land Use
Plan will generate about 34% more traffic than build out of the 2002 General Plan land use
designations.
The majority of the roadway segments are forecast to operate at acceptable levels of service (V/C
ratios less than or equal to 0.90 or LOS D or better). Three segments are projected to operate at
LOS E and three at LOD F at 2035 build out.
Washington Street segments between Avenue 42 and Miles Avenue and between Highway
111 and Eisenhower Drive (6-lane Major Arterial) are forecast to exceed theoretical
maximum carrying capacity by up to 3,000 VPD with the most problematic segment between
Fred Waring Drive and Miles Avenue. LOS D service volumes are exceeded by over 9,000
VPD.
Madison Street between Avenue 54 and Airport Boulevard (4-lane Primary Arterial) is
forecast to exceed theoretical maximum carrying capacity by approximately 4,900 VPD.
LOS D service volumes are exceeded by over 9,000 VPD.
Harrison Street between Airport Boulevard and Avenue 58 (8-lane Augmented Major) is
forecast to exceed theoretical maximum carrying capacity by approximately 3,800 VPD.
Although the capacity of Harrison Street was assumed to be that of an Augmented Major
Road (76,000 vehicles per day), it would likely operate as an Expressway due to limited
accessibility compared to an Augmented Major Road, thus carrying a larger capacity. Prior
study by the County raised the potential of grade-separated intersections to further enhance
capacity.
Of the 37 intersections analyzed, the following four are not expected to be able to accommodate
all the required build out improvements and therefore have the potential to be operating at
unacceptable levels of service by 2035 General Plan build out:
Terra Nova/La Quinta General Plan EIR
Section VIII. Growth Inducement
VIII-10
Washington Street @ Fred Waring Drive;
Adams Street @ Miles Avenue;
Jefferson Street @ Highway 111;
Madison Street @ Avenue 50.
It should also be noted that three of the four impacted intersections are shared between more than
one jurisdiction. For instance, the Washington Street/Fred Waring Drive intersection is located
within the corporate boundaries of the cities of La Quinta, Palm Desert and Indian Wells. In
these cases, close and on-going coordination between cities will be necessary to provide
optimum intersection improvements and to otherwise address forecast operational deficiencies.
However, even with the implementation of feasible mitigation measures, impacts will be
cumulatively considerable.
Water Resources
As discussed in Section III of this EIR, the Planning Area is located in the Whitewater River
Subbasin. The Whitewater Subbasin encompasses approximately 400 square miles and underlies
most of the Coachella Valley. There are five subareas within the Whitewater River Subbasin, and
the La Quinta Planning Area overlies the Thermal subarea, which is part of the Lower
Whitewater River Subbasin.
The Coachella Valley Water District (CVWD) serves as the water provider for the La Quinta
Planning Area. Implementation of General Plan Update is expected to increase water demand by
approximately 22,000 acre-feet, consisting of 6,555 acre-feet within the City, and 15,416 acre-
feet within the Sphere.
According to CVWD’s Urban Water Management Plan, CVWD expects to have sufficient water
supplies to serve the General Plan Update Planning Area and surrounding region through 2035
and beyond, including during normal, single, and multiple dry year conditions. As stated in
Section III, this increased demand will be met by groundwater, imported Colorado River water,
desalinated agricultural drain water, reclaimed water or a combination thereof.
Implementation of water conservation methods, including the use of water efficient appliances,
and advanced irrigation control for outdoor landscaping, will help reduce water demands. The
proposed General Plan Update includes policies and programs intended to promote and support
the conservative use of water resources for domestic purposes uses, and to encourage the use of
drought tolerant planting materials efficient irrigation systems for landscaping.
Nonetheless, factors such as periodic drought conditions in California, the potential for reduced
Colorado River imports, and increasing demand for water resources associated with population
growth affect the availability of water for future development. Although water demands are
expected to be met at build out and beyond, the proposed General Plan Update will contribute to
a reduction in groundwater in the Basin. As such, the implementation of the proposed General
Plan Update in conjunction with development within surrounding jurisdictions will result in
cumulatively considerable impacts to water resources.
Terra Nova/La Quinta General Plan EIR
Section IX: Organizations, Persons and Documents Consulted
IX-1
LA QUINTA GENERAL PLAN
ENVIRONMENTAL IMPACT REPORT
IX. ORGANIZATIONS, PERSONS AND DOCUMENTS
CONSULTED
A. Project Proponent
City of La Quinta
78-495 Calle Tampico
La Quinta, CA 92253-1504
B. Environmental / Planning Consultant
Terra Nova Planning & Research, Inc.
42635 Melanie Place, Suite 101
Palm Desert, CA 92253-1504
C. Air Quality Consultant
Terra Nova Planning & Research, Inc.
42635 Melanie Place, Suite 101
Palm Desert, CA 92253-1504
D. Biological Consultant
AMEC Earth & Environment, Inc.
3120 Chicago Avenue, Suite 110
Riverside, CA 92507
E. Cultural Consultant
CRM Tech
1016 East Cooley Drive, Suite A/B
Colton, CA 92324
Terra Nova/La Quinta General Plan EIR
Section IX: Organizations, Persons and Documents Consulted
IX-2
F. Geological Consultant
Earth Consultants International, Inc.
1642 East Fourth Street
Santa Ana, CA 92701
G. Noise Consultant
Urban Crossroads, Inc.
41 Corporate Park, Suite 300
Irvine, CA 92606
H. Paleontologic Consultant
CRM Tech
1016 East Cooley Drive, Suite A/B
Colton, CA 92324
I. Traffic Consultant
ITERIS, Inc.
1700 Carnegie Avenue, Suite 100
Santa Ana, CA 92705-5551
J. Public Agencies
California Department of Conservation
California Department of Water Resources & Public Affairs
California Integrated Waste Management Board
Coachella Valley Unified School District
Coachella Valley Water District
Desert Recreation District
Desert Sands Unified School District
National Recycling Coalition
Riverside County Fire
Riverside County Parks
Riverside County Planning Department
South Coast Air Quality Management District
Southern California Association of Governments
K. Utilities
Burrtec
Imperial Irrigation District
Southern California Gas Company
Terra Nova/La Quinta General Plan EIR
Section IX: Organizations, Persons and Documents Consulted
IX-3
L. Documents
2008-2010 Land Use Conversion Inventory, prepared by California Department of
Conservation, Division of Land Resource Protection.
AB 2588, prepared by State of California.
Average Housing Characteristics for 2005-2009, prepared by the American Community
Survey.
California Code of Regulations Title 23, prepared by Waters Division 2, Department of
Water Resources Chapter 2.7.
California Environmental Quality Act 2010, Statutes & Guidelines, prepared by AEP,
January 1, 2010.
California Government Code, Sections 65591, 65593, 65596.
California Water Code, Division 6 Part 2.2, §10530 et seq., as amended.
CEQA Guidelines sections 15064(i)(1) and 15130.
City of La Quinta Development Impact Fee Summary, December 8, 2008.
City of La Quinta General Plan Circulation Element Update Traffic Impact Analysis,
prepared by Iteris, Inc. May 2012.
City of La Quinta General Plan Update Noise Element Technical Report, prepared by
Urban Crossroads, Inc., June 3, 2011.
City of La Quinta General Plan Update: Biological Resources, prepared by AMEC Earth
& Environmental, Inc., June 2010.
City of La Quinta General Plan/Master Environmental Assessment, prepared by Terra
Nova Planning & Research, March 20, 2002.
Coachella Valley Water District 2011 Domestic Water Quality Summary, in the CVWD
2011 Domestic Water Quality Report, prepared by CVWD, 2011.
Coachella Valley Water District Development Design Manual, prepared by Coachella
Valley Water District, 2010.
County of Riverside General Plan, prepared by County of Riverside Transportation and
Land Use Management Agency, October 2003.
Terra Nova/La Quinta General Plan EIR
Section IX: Organizations, Persons and Documents Consulted
IX-4
Cultural Resources Technical Report for City of La Quinta General Plan (2010 Update),
prepared by CRM Tech, July 8, 2010.
CVWD 2011 Domestic Water Quality Table, prepared by CVWD, 2011.
Draft Coachella Valley Water District Urban Water Management Plan, prepared by
Montgomery Watson Harza, December 2010.
East County Airports Background Data: Bermuda Dunes and Environs, Riverside
County ALUCP, December, 2004.
Engineer’s Report on Water Supply and Replenishment Assessment: Lower Whitewater
River Sub-basin Area of Benefit, 2010-2011, prepared by Coachella Valley Water
District, April 2010.
Engineer’s Report on Water Supply and Replenishment Assessment: Lower Whitewater
River Sub-basin Area of Benefit, 2011-2012, prepared by Coachella Valley Water
District, May 2011.
Farmland GIS Data, provided through Riverside County by City of La Quinta Planning
Department.
Final 2007 Air Quality Management Plan, prepared by South Coast Air Quality
Management District, June 2007.
Final 2008 Regional Comprehensive Plan, prepared by the Southern California
Association of Governments, 2008.
Final Coachella Valley Water District Water Management Plan, prepared by
Mongomery Watson Harza, December 2005.
Final Draft Eastern Coachella Valley Area Land Use Plan as shown on Figure 3.20,
Riverside County General Plan, 2003.
Inland Empire Quarterly Economic Report, prepared by John E. Husing, Ph.D., October
2011.
La Quinta General Plan Air Quality Report, prepared by Terra Nova Planning and
Research, July 2011.
La Quinta Pressure Zones Map, prepared by Coachella Valley Water District, December
28, 2010.
Paleontologic Resources Technical Report for City of La Quinta General Plan (2010
Update), prepared by CRM Tech, August 12, 2010.
Terra Nova/La Quinta General Plan EIR
Section IX: Organizations, Persons and Documents Consulted
IX-5
Panorama (Specific Plan No. 362) Traffic Impact Analysis, prepared by Urban
Crossroads, Inc.
Profile of General Population and Housing Characteristics, for the City of La Quinta,
2010 US Census.
Riverside County Airport Land Use Compatibility Plan; Volume I, prepared by Mead &
Hunt, October 14, 2004.
Riverside County Fire Department Strategic Plan 2009-2029, prepared by Management
Partners, Inc., November 2009.
Riverside County Fire Protection and Emergency Medical Master Plan, January 2, 1986.
Riverside County Important Farmland 2008 Map, prepared by California Department of
Conservation, 2009.
Riverside County Important Farmland 2008, prepared by California Department of
Conservation, Division of Land Resource Protection, September 2009.
Riverside County Transportation Analysis Model (RivTAM), prepared by the Riverside
County Transportation Department, 2008.
South Coast Air Quality Management District Rules and Regulations, Adopted February
4, 1977.
Statewide Waste Characterization Study, prepared by the California Integrated Waste
Management Board, December 2004.
Table 1, Engineer’s Report on Water Supply and Replenishment Assessment: Lower
Whitewater River Sub-basin Area of Benefit, 2010-2011, prepared by Coachella Valley
Water District, April 2010.
Table 2, Engineer’s Report on Water Supply and Replenishment Assessment: Lower
Whitewater River Sub-basin Area of Benefit, 2010-2011, prepared by Coachella Valley
Water District, April 2010.
Table 3-1, Coachella Valley Urban Water Management Plan, prepared by Coachella
Valley Water District, November 2000.
Table 3, Engineer’s Report on Water Supply and Replenishment Assessment: Lower
Whitewater River Sub-basin Area of Benefit, 2011-2012, prepared by Coachella Valley
Water District, May 2011.
Table 4-2, Draft Coachella Valley Water District Water Management Plan, prepared by
Montgomery Watson Harza, December 2010.
Terra Nova/La Quinta General Plan EIR
Section IX: Organizations, Persons and Documents Consulted
IX-6
Table 4-4, Draft Coachella Valley Water District Water Management Plan, prepared by
Montgomery Watson Harza, December 2010.
Technical Background Report to the Safety Element of La Quinta 2035 General Plan
Update, prepared by Earth Consultants, Inc., June 2010.
Technical Background Report to the Safety Element Update, City of La Quinta,
California, prepared by Earth Consultants International, July 2010.
Technical Background Report to the Safety Element Update, City of La Quinta, CA,
prepared by Earth Consultants International, September 2010.
Update of Mineral Land Classification for Portland Cement Concrete-Grade Aggregate
in the Palm Springs Production-Consumption Region, prepared by California
Department of Conservation, California Geologic Survey, 2007.
Update of Mineral Land Classification for Portland Cement Concrete-Grade Aggregate
in the Palm Springs Production-Consumption Region; Special Report 198, prepared by
California Department of Conservation, California Geologic Survey, 2007.
Vista Santa Rosa Community Land Use Concept Plan, prepared by the County of
Riverside Planning Department, June 17, 2008.
Washington Street & Highway 111 TSM/TDM Corridor Study, prepared by VRPA
Technologies, Inc. June 2009.
Water Supply Study for additional information refer to section 4.5.2 on emerging
pollutants of concern.
Water Supply Study for the proposed La Quinta General Plan Update 2010, prepared by
Terra Nova Planning & Research, June 21, 2011.
Working Group III Contribution to the Intergovernmental Panel on Climate Change
Fourth Assessment Report, Climate Change 2007: Mitigation of Climate Change,
prepared by the Intergovernmental Panel on Climate Change, May 2007.
M. Correspondence
Personal communication, Kim Halsey, CVWD WRP-4, December 14, 2010.
Personal communication, Mark Johnson, CVWD, December 20, 2010.
Personal communication, James Kozero, Project Manager, DSUSD Facilities
Department, December 16, 2010.
Terra Nova/La Quinta General Plan EIR
Section IX: Organizations, Persons and Documents Consulted
IX-7
Personal communication, Jason Newman, Riverside County Fire Department Strategic
Planning, December 22, 2010.
Personal communication, Ray Salazar, CVWD-WRP-7, December 15, 2010.
Personal communication, Ken Stevens, Burrtec District Environmental Coordinator,
December 14, 2010.
Personal communication, Marcella Valdez, CVUSD Facilities Department, December
16, 2010.
Written communication provided by Guillermo Barraza, Customer Operations and
Planning, Imperial Irrigation District, December 21, 2010.
Written communication, Mark Johnson, Coachella Valley Water District, December 28,
2010.
Written communication, Lt. Jason Huskey, Assistant Police Chief, La Quinta Police
Department, Riverside County Sheriff’s Department, December 2, 2010.
Written communication, Bret Plumlee, Assistant City Manager, City of La Quinta,
December 6, 2010.
Written communication, Ryan Ross, Riverside County Waste Management Department,
December 17, 2010.
N. Web Sites
Airport Operation Statistics, Jacqueline Cochran Airport,
http://www.rcjcra.com/AirportInformation/AirportStatistics/tabid/77/Default.aspx,
accessed July 12, 2011.
Airport Operational Statistics, http://www.rcjcra.com, accessed December 17, 2010.
Bermuda Dunes Airport, http://bermudadunesairport.com/, accessed December 17,
2010.
Caltrans Hazardous Waste Management, http://www.dot.ca.gov/hq/env/haz/, accessed
December 17, 2010.
CERCLA Overview, http://www.epa.gov/superfund/policy/cercla.htm, accessed
December 6, 2010.
Cortese List: Section 65962.5(a):
http://www.calepa.ca.gov/sitecleanup/corteselist/SectionA.htm
Terra Nova/La Quinta General Plan EIR
Section IX: Organizations, Persons and Documents Consulted
IX-8
Department of Water Resources and Public Affairs,
www.publicaffairs.water.ca.gov/swp/.
Desert Recreation District, www.myrecreationdistrict.com, accessed November 22,
2010.
Emergency Services, http://www.la-quinta.org/Index.aspx?page=80, accessed December
13, 2010.
Facilities: Demographics,
http://www.coachella.k12.ca.us/interport/default.aspx?tabid=59, accessed November 23,
2010.
Hazardous Waste and Substances Site List, www.envirostor.dtsc.ca.gov, accessed
January 14, 2011.
http://redirect.conservation.ca.gov/DLRP/fmmp/county_info_results.asp. Important
http://senweb03.senate.ca.gov/focus/outreach/sd23/200911enews/SBX77FactSheet.pdf
California Senate Bill (SB) x7-7, accessed via Google search, December 14, 2010.
http://www.cvwd.org/about/waterandcv.php
http://www.maps.google.com/ accessed July 5, 2011.
http://www.mountainviewequestriancenter.com/About-Us.html
http://www.playinlaquinta.com/golf.html
http://www.rivcowm.org/HHW_Schedule.htm#_HHW_Collection_Locations
http://www.wrcc.dri.edu provided by Riverside County Western Regional Climate
Center.
Lake Cahuilla, Riverside County Parks, www.rivcoparks.org/parks/lake-cahuilla/lake-
cahuilla-recreation-area-home/, accessed July 5, 2011.
Office of Emergency Services, http://www.rvcfire.org/opencms/functions/oes/, accessed
December 17, 2010.
Parks and Trails, http://www.la-quinta.org/Index.aspx?page=19, accessed June 28, 2011.
Parks and Trails, www.la-quinta.org, accessed November 22, 2010.
PHMSA, http://www.phmsa.dot.gov/hazmat/about, accessed December 17, 2010.
Terra Nova/La Quinta General Plan EIR
Section IX: Organizations, Persons and Documents Consulted
IX-9
Publications, www.chp.ca.gov, accessed December 17, 2010.
Santa Rosa and San Jacinto Mountains National Monument, http://www.blm.gov/,
accessed November 22, 2010.
SBX7 7 (Steinberg) – November 2, 2009 Fact Sheet, Wastes-Hazardous Waste-Waste
Types, http://www.epa.gov/waste/hazard/index.htm, accessed December 6, 2010.
Union Pacific 2009 Annual Report”, www.up.com, accessed December 17, 2010.
www.envirostor.dtsc.ca.gov, accessed November 2, 2010.