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LA _QUINTA_.RESORT_ -.
x° SPECIFIC PLAN AMENDMENT NO. 6��T
PLANNING AREA 1
HYDROLOGY REPORT
FOR
ENVIRONMENTAL IMPACT REPORT •
PREPARED BY:
1 �C The Altum Group r, ,
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PYRAMID PROJECT MANAGEMENT �� ��� "���•��`�� � '
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July 13, 2009
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City of la Qulnta t r
{Tanning Department
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73255 El Paseo Drive, Suite 15
Palm Desert, CA 92260
760.346.4750 Tel
760.340.0089 Fax
The Altum Group
To:
Wally Nesbit
From:
Company:
City of La Quinta
❑
Address:
O
Phone:
❑
Date:
July 12, 2009
0
File:
Delivery:
Wally,
TRANSMITTAL
James Bazua, P.E.
For Your Information
For Your Approval
For Your Review
As Requested
Please find 2 copies of the La Quinta Resort Hydrology Report for Specific Plan No. 6. A
previous version of the report had received preliminary approval, before the latest changes to
Planning Area 1.
Thank you,
James Bazua, P.E.
Senior Project Manager
james.bazua @thealtumgroup.com
cc: Mike Peroni, TAG
received
li .I 1 4 . %r,19
Clte, of Lo Quhta
Planning ao-Lx.,rlrnant
Uprojects \C1007 Mecca \4088701 \dots \transmit \09 -07 -12 SPA Hydrology Submittal.doc
City ofLa Quinta
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DIST R I W-U-717HOW11AT. E�7 /15/09
Project Planner:
❑ Eric Ceja 1W5ll Nesbit?
funning (Department ❑ Yvonne Franco ❑ Stan Sawa
78-495 Calle Tampico 0 Andy Mogensen ❑ Jay Wuu -'
La Quinta, California 92253
OF PHONE: 760.777.7125 FAX: 760.777.1233 Please direct all correspondence to the
project planner o
- INTERDEPARTMENTAL COMMENT RE-.QUEST
i S1RIBUTION LIST: ; W? ❑ Fire ❑ Bldg ❑ Police ❑ ComSrvs ❑ C r?MIPP. IN
PROJECT NAME: ,La "Quinta= Resort Expansion 'JUG 15'
2009
.CASE NUMBER(s): SP 121 -E, Amd't #6; SDP 2008 -909 DevelOPmentSe *e_s
LOCATION: Within La Quinta Resort boundary - PA 1. of SP
DESCRIPTION: Expand resort by 631 rooms and 88,032 s.f. commercial
❑ PRELIMINARY REVIEW DUE:
Please review the attached project description and preliminary site plan and comment on any
significant preliminary concerns related to your department's policies and standards.
® ' PRO=d- ECT :REUI-EW;7 , J: uE 07�i29i09-
Please review and comment on the following as they relate to your department's policies and
standards (for revisions, also please consider impact on unrevised portions of the project):
❑
Project Plan Set
❑
Preliminary Title Report
❑ Initial ❑ Revision
❑ Initial ❑- Revision
"^ `
❑
Traffic Stud
`?
P_reliminary Hydrology: Report,
❑ Initial ❑ Revision
❑ Initial B �Revision�
❑
Preliminary jWQMP
❑
Geotechnical Report
❑ Initial ❑ Revision
❑ Initial ❑ Revision
❑
Other
❑
Other
❑ Initial ❑ Revision
❑ Initial ❑ Revision
❑
Other
❑
Other
❑ Initial ❑ Revision
.❑ Initial ❑ Revision y
❑ CONDITIONS OF APPROVAL DUE:
This project is now scheduled for an upcoming public hearing; please provide all conditions of
approval recommended by your department for each action associated with the project (i.e.
TTM, SDP, etc.). After all conditions are received and consolidated, a copy will be provided
to the applicant for review and discussion prior to, inclusion in the staff report. -
.T�. __._
SPECIAL�NOTE:' 1._copy= provided =per_P�Gble SP=level hydroE er ports
If the requested due date can not be met, please inform the project planner as soon as possible.
Interdepartmental Comment Request . = Page 1 of 1
Standard Response Times: PreliminaryReview -2wks, InitialProjectReview -3wks, MajorRevision -3wks, MinorRevision -2wks, CoA -3wks
P:\FORMS \Interdepartmental Comment Request Fill -In Form.doc 03.25.09
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4. Please provide a reference Vicinity Map located within the first section of the SDP
Hydrology Report.
5. Please provide justification for the assumed values of the Impervious and Runoff
Index coefficients used. Please discuss the surface soil assumptions from both
the Soil Conservation Map and the companion Geotechnical Report.
Sincerely,
J uimothy R. n s n, P. E.
blic Wo s ctor /City Engineer
TO:
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Tlldf 4 4 a"
P.O. Box 1504
LA QUINTA, CALIFORNIA 92247 -1504
78 -495 CALLE TAMPICO
LA QUINTA, CALIFORNIA 92253
TRANSMITTAL MEMO
Wally Nesbit, Principal Planner
PUBLIC WORKS DEPARTMENT
(760) 777 -7075
FAX (760).777 -7155
received
JUL 112009
City of La Quinta
PfanrNn9 Department
SUBJECT: CRN /ECN 09034 - SDP 08 -909 COMPONENT - LA QUINTA RESORT &
CLUB (HOTEL AND CONFERENCE CENTER) HYDROLOGY REPORT;
PLANNING AREA #1, LA QUINTA RESORT EXPANSION, SPECIFIC
PLAN AMENDMENT #6 (SEE CRN /ECN 09008)
DATE: July 28, 2009
Public Works has reviewed the "La Quinta Resort, Specific Plan Amendment No. 6,
Planning Area 1, Hydrology Report for Environmental Impact Report" dated July 13,
2009 prepared by The Altum Group and has deemed the document complete for
application processing. We have reviewed 'and approved the document for Specific
Plan entitlement.
Please incorporate the following comments into the upcoming La Quinta Resort,
Hotel /Conference Subarea C, Site Development Permit (SDP) Hydrology Report:
1. Please comply with Public Works Engineering Bulletins 06 -15 and 06 -16 regarding
underground retention, hydrology and hydraulic report criteria and calculation
methods. Proposed underground retention locations appear to have insufficient
setback distances.
2. Please provide a Geotechnical Report for the project which defines soil conditions
and reviews potential hydroconsolidation for the SDP redevelopment area.
Extensive use of underground retention adjacent to building foundations is of
specific concern.
3.. Please provide a preliminary Project Specific Water Quality Management Plan
(WQMP). Please include, a summary map of all offsite flows, clearly defining La
Quinta Resort tributary areas, storm water volumes and golf course retention
capacity.
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4.
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CITY OFLA QUINTA
PUBLIC WORKS DEPARTMENT
INTERNAL
TRANSMITTAL SHEET
ITEM: - SDP 08 -909 COMPONENT - LA QUINTA RESORT
& CLUB (HOTEL AND CONFERENCE CENTER)
HYDROLOGY REPORT; PLANNING AREA #1, LA QUINTA
RESORT EXPANSION, SPECIFIC PLAN AMENDMENT #6.
(SEE CRN /ECN 09008) received
CRN/ ECN: 09034
TRACT: SDP 08 -909
FROM: PAUL GOBLE
DATE: JULY 30, 2009
ASSIGNED TO (PLANNING): IA)aLlt PxS
PLEASE RETURN TO
PAUL GOBLE, SENIOR ENGINEER
FOR FINAL PROCESSING
THANK YOU!
® REVIEW AND COMMENT: Please see attached comments.
❑ SIGNATURE
COUNTER TECHNICIAN
TELEPHONE: 760 777 7075
FAX: 760 777 7155
JUL 31 2009
Clty of La Guinta
Manning Department
� LA QUINTA RESORT
' SPECIFIC PLAN AMENDMENT NO.6
PLANNING AREA 1
HYDROLOGY REPORT
FOR
' ENVIRONMENTAL IMPACT REPORT
PREPARED BY:
The Altum Group`
■
' 73 -255 El Paseo Drive, Suite 15
PALM DESERT, CA 92260
Prepare Un r th Supervision of: pQ *10fESsj�y
F;ON a 9l may_
w No: 5M y m
James l. Bazua
' R.C.E. 58394 q CIVi �\Q'
Expiration Date: December 31, 2010 F.of CAUFp�
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LA QUINTA RESORT
SPECIFIC PLAN AMENDMENT NO.6
PLANNING AREA 1
HYDROLOGY REPORT '
FOR
ENVIRONMENTAL IMPACT REPORT
TABLE OF.CONTENTS:
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I PURPOSE AND SCOPE
II DESIGN CRITERIA.
III RATIONAL METHOD CALCULATIONS - HOTEL CONFERENCE CENTER
EXPANSION
IV PIPE CAPACITY CALCULATION
V RETENTION BASIN CALCULATIONS
VI CONCLUSIONS AND RECOMMENDATIONS
VII OFF -SITE MOUNTAIN RUNOFF
VIII MS4 PERMIT
IX APPENDIX <`A" - REFERENCE MATERIAL
X APPENDIX `B"
HYDROLOGY MAPS
V,
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' PURPOSE AND SCOPE
' `T ose of this report i to provide a ydrologic study of the La Uinta Resort,
ecific Plan men ment o. ,Planning Area l located ,focusing on the
anticipa e impact to the age aciIities due to proposed development within the
resort. This report then proposes methods of storm flow protection based on these impacts.
The results contained herein are largely qualitative given the preliminary stage of the project
development.
The La Quinta Resort is currently developed. Existing on -site and off -site storm drain
facilities have been constructed to capture storm flows tributary to the Resort. This report
will compare the existing and proposed use of each site development area in terms of the'
projected storm runoff. The impact on existing drainage facilities for each proposed site ,S
development area will then be examined.
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The rainfall data and design criteria used in is report are consistent with current City of La
Quinta standards for hydrology and h lic design. Rainfall totals are based on NOAA
National Weather Service data, and t C va e is based on RCFC &WCD values for various
types of development. Since most of t proposed uses for the site development areas
addressed in this report will have the same type of land use designation as the current uses,
the proposed type of development is not expected to be the cause of a significant increase in
runoff for each development area. However, current NOAA rainfall totals accepted by City
of La Quinta are generally more conservative than data had commonly been obtained from
the Riverside County Hydrology Manual in the past.
Approved Hydrology Reports used in the design of the existing storm drain system for the
majority of La Quinta Resort Planning Area 1 are not available. Nevertheless, projected
storm runoff totals should be based on accepted NOAA rainfall intensity figures and
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proposed type of development in order to determine if the existing storm drain system 5
provides sufficient capacity to satisfy City of La Quinta Standards. s�,� red
This report seeks to provide a discussion of impacts that result from proposed development , �.
within La Quinta Planning area 1 site. cj��� %A
SITE DEVELOPMENT AREAS'
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SPA VILLAS (A PORTION OF SUBAREA B)
The proposed Spa Villas development area is approximately 2.52 total acres in size, located
near the westerly boundary of the La Quinta Resort Planning Area 1, adjacent to Calle
Obregon to the east (see Hydrology Map included). The Spa Villas development area drains
in an easterly direction into an existing on -site, underground drainage system along Calle
Obregon. This report seeks .to evaluate the impact of the proposed development on the
capacity of the existing storm drain system along Calle Obregon based on currently accepted
rainfall data.
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An existing approved Hydrology and Hydraulic Calculations Report prepared by MDS
Consulting in April 1998, provides details related to the original design of the Calle Obregon
storm drain system, including pipe sizes, invert elevations and assumed tributary areas.
Sufficient data is available to estimate the capacity of the existing storm drain system based
on criteria currently accepted by the City of La Quinta. This information can then be used to
understand the impact of developing the easterly half of the Spa Villas development area on
the existing storm drain system.
The Spa Villas Development Area is proposed to be a condominium type land use. 1998
MDS Hydrology Report which was used to design the existing storm drain system along
Calle Obregon assumes that the same area is a single family (1/4 acre lot) type land use.
Condominium type land use generally produces less runoff than single family (1/4 acre lot)
type developments when all other factors are equal. Therefore, the proposed type of land use
for the Spa Villas development (condominium) is not expected to be the source of a
significant increase in the projected runoff totals tributary to Calle Obregon.
GROVE UNITS, MORGAN HOUSE, WELLNESS CENTER (A PORTION OF
SUBAREA B)
The proposed Grove Units, Morgan House improvements and Wellness Center developments
are located within the "on= site" drainage basin defined in the original 1998 MDS Hydrology
Report (see MDS On -Site Hydrology Map, included). According to the original report, this
development area is originally assumed to be a single family (1 acre lot) type of development
with a C value of 0.52. The exception is the existing date grove on which the grove units are
proposed which is assumed to be an undeveloped type use with a C value of 0.43.
The post development condition within the existing date grove area will have a condominium
type land use which will contribute to an increase in storm runoff for this area. Because of
the relatively small size of the affected area, the amount of additional runoff is unlikely
to warrant improvements to the main orn -site storm drain system. The existing Morgan
House improvements and proposed Wellness Center development will maintain their original
land use designation in the post development condition and will not contribute an increase in
storm discharge based on the new type of development.
HOTEL /CONFERENCE CENTER EXPANSION (SUBAREA C)
The proposed Hotel /Conference Center development area is located within the boundary of
the La Quinta Hotel Planning Area 1. The proposed improvements involve 9.9 acres of
renovation and expansion of existing facilities. The Hotel /Conference Center improvements
lie within a 15.4 acre subarea (see Hydrology Map, included) that drains into an existing
underground storm drain system.
The existing drainage facilities for this development area include an extensive system of
inlets and area drains that lead to a common 24" mainline storm drain system that is designed
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to convey runoff toward the easterly. boundary of the La Quinta Resort and Spa. Runoff
collected in the storm drain system is then directed to a wet well located near the intersection
of the Entry Road and Eisenhower Drive, where it is pumped out of the wet well into a force
main pipe located underneath Eisenhower Drive. The force main terminates in an existing
lake, adjacent to the existing off -site Golf Course Channel.
An increase in the amount of storm runoff due to the proposed improvements is not
anticipated since the post development condition proposes the, same type of land use
that currently exists.
GOLF VILLAS (SUBAREA D)
The proposed 5.8 acre golf villas development area is located within the boundary of the La
Quinta Hotel Planning Area 1, immediately adjacent to Eisenhower Drive and bounded to the
north by the existing entry drive. Both existing and proposed land uses are condominium
type developments for the purposes of this hydrologic discussion. The existing drainage
pattern for the area within the proposed development boundary relies on surface flow to
convey runoff in a southeasterly direction toward an existing through curb drain that directs
runoff onto Eisenhower Drive. Gutter flow on Eisenhower Drive is directed toward the south
where it is collected in existing curb inlets and ultimately directed into the existing golf
course channel.
DESIGN CRITERIA
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DESIGN CRITERIA
MDS CONSULTING HYDROLOGY AND HYDRAULICS REPORT (1998)
e Antecedant Moisture Condition —
100 year — Not Available
• Antecedant Moisture Condition —10
year — Not Available
• Hydrologic Soil Type `A'
100 year - 1 hour Precipitation
1.6 in/hr.
• 10 year — 1 hour Precipitation
1.0 in/hr
• 2 year — 1 hour Precipitation
0.6 in /hr
• Slope Intensity Duration Curve
0.58
STANTEC CONSULTING, INC. HYDROLOGY REPORT
The following Riverside County Flood Control
District (RCFCD) parameters were. used in
the preparation of the analyses:
• Antecedant Moisture Condition —
100 year 3
• Antecedant Moisture Condition —
10 year 2
• 100 year — 1 Hour'Precipitation
2.11" NOAA Atlas 14
• 100 year — 3 Hour Precipitation
2.71 " - NOAA Atlas 14
• 100 year — 6 Hour Precipitation
3.28 "--- NOAA Atlas 14
• 100 year — 24 Hour Precipitation
4.38 ""' NOAA Atlas 14
• 10 year — 1 Hour Precipitation
0.95" NOAA Atlas 14
2 year — 1 Hour Precipitation
0.45" NOAA Atlas 14
• Hydrologic Soil Type "C"
• Slope Intensity Duration Curve
0.58
RATIONAL METHOD CALCULATIONS
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Riverside County Rational Hydrology.Program
CIVILCADD /CIVILDESIGN Engineering Software,(c) 1989 -'2001
Version 6.4
Rational Hydrology Study Date: 03/10/09
' File:100yearhote1conference.out ---- --- ---
HOTEL/CONFERENCE CENTER EXPANSION
100 YEAR STORM EVENT
ESTIMATED DISCHARGE BASED ON DEVELOPMENT AREA FOOTPRINT
- -- - - -- - -- NODE_ 1 _TO- -NODE--2- (.SEE - _HYDROLOGY - . MAP )-.- -- - = - -- - -- - — - -- - - -- - z -- - -
--------------------------------=--------------------------------
s * * * * * * * ** Hydrology Study Control Information * * * * * * * * **
' English (in.lb) Units used in input data file,.
----------.--------------------------- -.------------------------- -
' The Keith Companies, Moreno,Valley, CA - SIN 707,
Rational Method Hydrology Program based on
Riverside County Flood Control & Water Conservation District
1978 hydrology manual
Storm event•(year) = 100.00 Antecedent Moisture Condition = 3•
2 year, l hour precipitation = 0.450(In�.)
' 100 year,-1 hour precipitation = 2.110(In.)
Storm event year = 100.0
Calculated rainfall intensity data:
' 1 hour .intensity = 2.110(In /Hr)
Slope of intensity duration curve = 0.5800
' ++++++++++++++++++++++++++++++++++ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + ++
Process from Point /Station 1.000 to Point /Station
' 2.000
* * ** INITIAL AREA EVALUATION * * **
Initial area flow distance = 875.000(Ft.)
Top (of initial area) elevation = 49.000(Ft.)
Bottom (of initial area) elevation = 45.000(Ft.)
Difference in elevation = 4.000(Ft.)
Slope = ' 0.00457 s(percent)= 0.46
TC = k(0.370) *[(length ^3) /(elevation change.)] ^0.2
Initial area time of concentration = 16.330 min.
' Rainfall intensity = 4.488(In /Hr) for a 100.0 year storm
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CONDOMINIUM subarea type
Runoff Coefficient = 0.884
1
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.000
Decimal fraction soil group C = 1.000
'1
Decimal fraction soil group D = 0.000
RI index for soil(AMC 3) = 84.40
Pervious area fraction = 0.350; Impervious fraction = 0.650
Initial subarea runoff = 21.812(CFS)
1
Total initial stream area = 5.500(Ac.)
Pervious area fraction = 0.350
End of computations, total study area = 5.50 (Ac.)
The following figures may
'
be used for a unit hydrograph study of the same area.
Area averaged g pervious area fraction(Ap) = 0.350
1
Area averaged RI index number = 69.0
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Riverside County Rational Hydrology Program
CIVILCADD /CIVILDESIGN Engineering Software,(c) 1989 - 2001
Version 6.4
Rational Hydrology.Study Date: 03/10/09
File :100yearhotelconference3to4.out
-----------------------------------------------------------------
HOTEL /CONFERENCE CENTER EXPANSION
100 YEAR STORM EVENT
ESTIMATED DISCHARGE BASED ON DEVELOPMENT AREA FOOTPRINT
NODE 3 TO NODE 4
-----------------------------------------------------------------
* * * * * * * ** Hydrology Study Control Information * * * * * * * * **
English (in -lb) Units used in input data file
--------------------------------------------------
The Keith Companies, Moreno Valley, CA - SIN 707
Rational Method Hydrology Program based on
Riverside County Flood Control & Water Conservation District
1978 hydrology manual
Storm event (year) = .100.00 Antecedent Moisture Condition = 3
2 year, 1 hour precipitation = 0.450(In.)
100 year, 1 hour precipitation = 2.110(In.)
Storm event year.= 100.0
Calculated rainfall intensity data:
1 hour intensity = 2.110(In /Hr)
Slope of intensity duration curve = 0.5800
++++++++++++++++++++++++++++++++++ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + ++
Process from Point /Station 3.000 to Point /Station
4.000
* * ** INITIAL AREA EVALUATION * * **
tInitial area flow distance = 820.000(Ft.)
Top (of initial area) elevation = 46.900(Ft.)
' Bottom (of initial area) elevation = 43.500(Ft.)
Difference in elevation = 3:400(Ft.)
-
Slope 0.00415 s(percent) 0.41
TC = k(0.300) *[(length ^3) /(elevation change)] ^0.2
' Initial area time of concentration = 13.156 min.
Rainfall intensity = 5.088(In /Hr) for a 100.0 year storm
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COMMERCIAL subarea type
Runoff Coefficient = 0.896
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.000
Decimal fraction soil group C = 1.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 3) = 84.40
Pervious area fraction = 0.100; Impervious fraction = 0.900
Initial subarea runoff = 45.122(CFS)
Total initial stream area = 9.900(Ac.)
Pervious area fraction = 0.100
End-of computations, total study area = 9.90 (Ac.)
The following figures may
be used for a unit hydrograph study of the same area.
Area averaged pervious area fraction(Ap) = 0.100
Area averaged RI index number = 69.0
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Existing 24 in SD Pipe Capacity - Hotel_Congerence Center.txt
Manning Pipe Calculator
Given Input Data:
shape...........................
solving for .....................
Diameter ............
Flowrate ........................
Slope ........................
Manni.ng's n .....................
computed Results:
Depth...........................
Area..........................
Wetted Area .....................
wetted Perimeter ................
Perimeter .......................
velocity .. ...........
Hydraulic Radius ................
Percent Full ....................
Full flow Flowrate ..............
Full flow velocity ...........
Critical Informati
Critical depth ..................
Critical slope .................
Critical velocity ...............
critical area ...................
,Critical perimeter ..............
Critical hydraulic radius .......
Critical top width ..............
Specific energy .................
Minimum energy ...............
Froude number ...................
Flow condition ..................
Circular
Depth of Flow
2.0000 ft
18.8494 cfs
0.0060 ft /ft
0.0130
1.8727 ft
3.1416 ft2
3.0576 ft2
5.2630 ft
6.2832 ft
6.1648 fps
0.5810 ft
93.6345
17.5232 cfs
5.5778 fps
on
1.5622 ft
0.0061 ft /ft
6.9936 fps
2.6952 ft2
4.2660 ft
0.6318 ft
2.0000 ft
2.3194 ft
2.3433 ft
0.9757
Subcritical
Page 1
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� RETENTION BASIN CALCULATIONS
SITE DEVELOPMENT
AREA
PROPOSED
VOLUM]
AREA'
-(ac.)
DEVELOPMENT
REQUIRI
•�[
TYPE
(cu. ft.)
SPA VILLAS
2.52.
CONDOMINIUM
16,326,
•HOTEUCONFERENCE
• 15.4
COMMERCIAL/
113,479
CENTER EXPANSION•
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C0ND0N4INF M •,
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GOLF VU-LAS,
5.6
CONDOMIlVIUM
36,281
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C
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RCFCD SYNTHETIC UNIT HYDROGRAPH
2
DATA INPUT SHEET
3
4
WORKSHEET PREPARED BY: IJAMES
R. BAZUAI
P.E.
5
6
PROJECT NAME
LA QUINTA RESORT
SPECIFIC PLAN AMENDMENT
7
TKC JOB #
2017110600
8
9 lCONCENTRATION
POINT DESIGNATION
1 -
10
AREA DESIGNATION JSPA
VILLAS
11
12
TRIBUTARY AREAS
ACRES
13
14
COMMERCIAL
15
PAVING /HARDSCAPE
16
SF - 1 ACRE
17
SF - 1/2 ACRE
18
SF - 1/4 ACRE
19
MF - CONDOMINIUMS
2.52
20
MF- APARTMENTS
21
MOBILE HOME PARK
22
LANDSCAPING
23
RETENTION BASIN
24
GOLF COURSE
25
MOUNTAINOUS
26
LOW LOSS RATE (PERCENT)
90%
27
28
LENGTH OF WATERCOURSE (L)
410
29
LENGTH TO POINT OPPOSITE CENTROID (Lca)
200
30
31
ELEVATION OF HEADWATER
50.5
32
ELEVATION OF CONCENTRATION POINT
47.5
33
34
AVERAGE MANNINGS'N' VALUE
- 0.02
35
36
STORM FREQUENCY (YEAR)
,100
37
38
POINT RAIN
39
3 -HOUR
2.71
40
6 -HOUR
.3.28
41
24 -HOUR
. 4.38
42
43
BASIN CHARACTERISTICS:
ELEVATION
AREA
44
45
46
47
48
.
49
50
51
52
PERCOLATION RATE (in /hr)
0
53
54
DRYWELL DATA
55
NUMBER USED
56
1 PERCOLATION RATE cfs
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RCFCD SYNTHETIC UNIT HYDROGRAPH METHOD PROJECT:
BASIC DATA CALCULATION FORM TKC JOB #
SHORTCUT METHOD BY
LA QUINTA RESORT SPECIFIC PLAN AMENDMENT NO. 6, PLAI
2017110600
:S R. BAZUA, P.E. DATE 7/13/2009
3 -HOUR
6 -HOUR
PHYSICAL DATA
EFFECTIVE RAIN (in)
1.80
1.56
[11 CONCENTRATION POINT
FLOOD VOLUME (cu -ft)
(acre -ft)
16,463
0.38
14,311
0.33
9,449
0.22
1
16,326
0.37
[21 AREA DESIGNATION
9,371
0.22
PEAK FLOW (cfs)
5.95
4.78
SPA VILLAS
MAXIMUM WSEL (ft)
3 AREA - ACRES
2.520
4 L -FEET
410
5 L -MILES
0.078
6 La -FEET
200.00
7 La -MILES
0.038
8 ELEVATION OF HEADWATER
50.5
9 ELEVATION OF CONCENTRATION POINT
47.5
10 H -FEET
3
11 S- FEET /MILE
38.6
[121 S^0.5
6.22
13 L'LCA/S^0.5
0.000
(141 AVERAGE MANNINGS'N'
0.02.
[151 LAG TIME -HOURS
0.03
[161 LAG TIME - MINUTES
1.6
17 100% OF LAG- MINUTES
1.6
18 200 %OFLAG - MINUTES
3.1
19 UNIT TIME - MINUTES 100% -200% OF LAG
5
(241 TOTAL PERCOLATION RATE (cfs)
0.00 .
RAINFALL
DATA
[1] SOURCE
[2] FREQUENCY -YEARS 100
[3] DURATION:
3 -HOURS
6 -HOURS
24 -HOURS
[4)
POINT
RAIN
INCHES
(Plate-E-5.2
[51
AREA
[6)
[71
AVERAGE
POINT
RAIN
INCHES
181
POINT
RAIN
INCHES
Plate E -5.4
191
AREA
(10]
x[11]
AVERAGE
POINT
RAIN
INCHES
[12)
POINT
RAIN
INCHES
Plate E -5.6
[13]
AREA
(141
[151
AVERAGE
POINT
RAIN
INCHES
2.71
2.520
1.00
2.71
3.28
2.520
1.00
3.281
4.38
2.520
1.00
4.38
0.00
0.00
0.00
0.00
1
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
SUM [5] 1 2.52 SUM [7)
[16] AREA ADJ FACTOR
[171 ADJ AVG POINT RAIN
2.71
SUM [9)
2.52 SUM [111
3.28
SUM [13] 1 2.52 SUM [15]
4.38
1.000
1.000
1.000
2.71
3.28
4.38
STORM EVENT SUMMARY
DURATION
3 -HOUR
6 -HOUR
24 -HOUR
EFFECTIVE RAIN (in)
1.80
1.56
1.03
FLOOD VOLUME (cu -ft)
(acre -ft)
16,463
0.38
14,311
0.33
9,449
0.22
REQUIRED STORAGE (cu -ft)
(acre -ft)
16,326
0.37
14,193
0.33
9,371
0.22
PEAK FLOW (cfs)
5.95
4.78
0.83
MAXIMUM WSEL (ft)
k
Plate E -2.1
Page 2 of 18
RCFCD SYNTHETIC UNIT HYDROGRAPH METHOD
PROJECT LA QUINTA RESORT SPECIFIC PLAN AMENDMENT NO. 6, PLANNING
CONCENTRATION POINT: 1
BY MES R. BAZUA, P.E. -DATE 7/13/2009
DJUSTED LOSS RATE
SOIL
GROUP
Plate C -1
LAND USE
RI
NUMBER
Plate E -6.1
PERVIOUS
AREA
INFILTRATION
RATE
(in /hr)
Plate E -6.2
DECIMAL
PERCENT
OF AREA
IMPERVIOUS
Plate E -6.3
ADJUSTED
INFILTRATION_
RATE
(in /hr)
AREA
AVERAGE
ADJUSTED
INFILTRATION
RATE
(in /hr)
A
COMMERCIAL
32
0.74
90%
0.14
0.00
0.000
0.0000
A
PAVING /HARDSCAPE
32
0.74
100%
0.07
0.00
0.000
0.0000
A
SF - 1 ACRE
32
0.74
20%
0.61
0.00
0.000
0.0000
A
SF - 1/2 ACRE
32
0.74
40%
0.47
0.00
0.000
0.0000
A
SF - 1/4. ACRE
32
- 0.74
50%
0.41
0.00
0.000
0.0000
A
MF - CONDOMINIUMS
32
0.74
6 5 0/.D
0.31
2.52
1.000
0.3071
A
MF - APARTMENTS
32
0.74
80%
0.21
0.00
0.000
0.0000
A
MOBILE HOME PARKS
32
0.74
75 %.
0.24
0.00
0.000
0.0000
A
LANDSCAPING
32
0.74
0%
0.74
0.00
0.000
0.0000
A
RETENTION BASINS
32
0.74
0%
0.74
0.00
0.000
0.0000
A
GOLF COURSE
32
0.74
0%
0.74
0.00
0.000
0.0000
D
MOUNTAINOUS
93
0.95
90%
0.18
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
SUMI 2.52 SUMI 0.3071
VARIABLE LOSS RATE CURVE 24 -HOUR STORM ONLY)
Fm= 0.15355
C= 0.00284
Ft= C(24- (T/60))A1.55 = 0.00284 (24- (T/60))A1.55 + 0.15 in /hr
LOW LOSS RATE (80 -90 PERCENT) = 90%
Where:"
T =Time in minutes. To get an average value for each unit time period, Use T =1/2 the unit time for the first time period,
T =1 1/2 unit time for the second period, etc.
Plate E -2.1
Page 4 of 18
RCFCD SYNTHETIC UNIT HYDROGRAPH METHOD
100 YEAR - 3 HOUR STORM EVENT
PROJECT: LA QUINTA RESORT SPECIFIC PLAN AMENDMENT NO. 6, P
CONCENTRATION POINT: 1
BY: IES R. BAZUA, DATE 7113/2009
EFFECTIVE
RAIN CALCULATION FORM
DRAINAGE AREA -ACRES 2.52
UNIT TIME - MINUTES 5
LAG TIME - MINUTES 1.57
UNIT TIME - PERCENT OF LAG 318.5
TOTAL ADJUSTED STORM RAIN - INCHES 2.71
CONSTANT LOSS RATE -in/hr 0.31
LOW LOSS RATE - PERCENT 90%
TOTAL PERCOLATION RATE (cfs) 0.00 cfs
Unit Time
Period
Time
Minutes Hours
Pattern
Percent
Plate E -5.9
Storm
Rain
in/hr
Loss Rate
in/hr
Max Low
Effective
Rain
in /hr
Flood
Hydrograph
Flow
cfs
Required
Storage
cf
1
5
0.08
1.3
0.423
0.31
0.38
0.12
0.29
87.44
2
10
0.17
1.3
0.423
0.31
0.38
0.12
0.29
87.44
3
15
0.25
1.1
0.358
0.31
0.32
0.05
0.13
38.27
4
20
0.33
1.5
0.488
0.31
0.44
0.18
0.46
136.61
5
25
0.42
1.5
0.488
0.31
0.44
0.18
0.46
136.61
6
30
0.50
1.8
0.585
0.31
0.53
0.28
0.70
210.36
7
35
0.58
1.5
0.488
0.31
0.44
0.18
0.46
136.61
8
40
0.67
1.8
0.585
0.31
0.53
0.28
0.70
210.36
9
45
0.75
1.8
0.585
0.31
0.53
0.28
0.70
210.36
10
50
0.83
1.5 '
0.488
0.31
0.44
0.18
0.46
136.61
11
55
0.92
1.6
0.520
0.31
0.47
0.21
0.54
161.19
12
60
1.00
1.8
0.585
0.31
0.53
0.28
0.70
210.36
13
65
1.08
2.2
0.715
0.31
0.64
0.41
1.03
308.71
14
70
1.17
2.2
0.715
0.31
0.64
0.41
1.03
308.71
15
75
1.25
2.2
0.715
0.31
0.64
0.41
1.03
308.71
16
80
1.33
2.0
0.650
0.31
0.59
0.34
0.87
259.53
17
85
1.42
2.6
0.846
0.31
0.76
0.54
1.36
407.05
18
90
1.50
2.7
0.878
0.31
0.79
0.57
1.44
431.63
19
95
1.58
2.4
0.780
0.31
0.70
0.47
1.19
357.88
20
100
1.67
2.7
0.878
0.31
0.79
0.57
1.44
431.63
21
105
1.75
3.3
1.073
0.31
0.97
0.77
1.93
579.14
22
110
1.83
3.1
1.008
0.31
0.91
0.70
1.77
529.97
23
115
1.92
2.9
0.943
0.31
0.85
0.64
1.60
480.80
24
120
2.00
3.0
0.976
0.31
0.88
0.67
1.68
505.39
25
125
2.08
3.1
1.008
0.31
0.91
0.70
1.77
529.97
26
130
2.17
4.2
1.366
0.31
1.23
1.06
2.67
800.41
27
135
2.25
5.0
1.626
0.31
1.46
1.32
3.32
997.09
28
140
2.33
3.5
1.138
0.31
1.02
0.83
2.09
628.31
29
145
2.42
6.8
2.211
0.31
1.99
1.90
4.80
1439.62
30
150
2.50
7.3
2.374
0.31
2.14
2.07
5.21
1562.55
31
155
2.58
8.2
2.667
0.31
2.40
2.36
5.95
1783.81
32
160
2.67
5.9
1.919
0.31
1.73
1.61
4.06
1218.35
33
165
2.75
2.0
0.650
0.31
0.59
0.34
0.87
259.53
34
170
2.83
1.8
0.585
0.31
0.53
0.28
0.70
210.36
35
175
2.92
1.8
0.585
0.31
0.53
0.28
0.70
210.36
36
180
3.00
0.6
0.195
0.31
0.18
0.02
0.05
14.75
EFFECTIVE RAIN & FLOOD VOLUMES SUMMARY
EFFECTIVE RAIN (in)
1.80
FLOOD VOLUME (acft)
0.38
FLOOD VOLUME (cult)
16462.61
REQUIRED STORAGE (acft)
0.37
REQUIRED STORAGE (cuft)
16326.49
PEAK FLOW RATE (cfs)
5.95
Plate E -2.2
Page 6 of 18
RCFCD SYNTHETIC UNIT HYDROGRAPH METHOD
100 YEAR - 6 HOUR STORM EVENT
PROJECT: LA OUINTA RESORT SPECIFIC PLAN AMENC
CONCENTRATION POINT: 1
BY: JAMES R. BAZ DATE: 7/13/2009
EFFECTIVE
RAIN CALCULATION FORM
DRAINAGE AREA -ACRES 2.52
UNIT TIME - MINUTES 5
LAG TIME - MINUTES 1.57
UNIT TIME - PERCENT OF LAG 318.5
TOTAL ADJUSTED STORM RAIN - INCHES 3.28
CONSTANT LOSS RATE -in/hr 0.307
LOW LOSS RATE - PERCENT 90%
TOTAL PERCOLATION RATE (cfs) 0.00 cfs
Unit Time
Period
Time
Minutes Hours
Pattern
Percent
Plate E -5.9
Storm
Rain
in/hr
Loss Rate
in/hr
Max Low
Effective
Rain
in/hr
Flood
Hydrograph
Flow
cfs
Required
Storage
cf
1
5
0.08
0.5
0.197
0.31
0.18
0.02
0.05
14.88
2
10
0.17
0.6
0.236
0.31
0.21
0.02
0.06
17.85
3
15
0.25
0.6
0.236
0.31
0.21
0.02
0.06
17.85
4
20
0.33
0.6
0.236
0.31
0.21
0.02
0.06
17.85
5
25
0.42
0.6
0.236
0.31
0.21
0.02
0.06
17.85
6
30
0.50
0.7
0.276
0.31
0.25
0.03
0.07
20.83
7
35
0.58
0.7
0.276
0.31
0.25
0.03
0.07
20.83
8
40
0.67
0.7
0.276
0.31
0.25
0.03
0.07
20.83
9
45
0.75
0.7
0.276
0.31
0.25
0.03
0.07
20.83
10
50
0.83
0.7
0.276
0.31
0.25
0.03
0.07
20.83
11
55
0.92
0.7
0.276
0.31
0.25
0.03
0.07
20.83
12
60
1.00
0.8
0.315
0.31
0.28
0.01
0.02
5.88
13
65
1.08
0.8
0.315
0.31
0.28
0.01
0.02
5.88
14
70
1.17
0.8
0.315
0.31
0.28
0.01
0.02
5.88
15
75
1.25
0.8
0.315
0.31
0.28
0.01
0.02
5.88
16
80
1.33
0.8
0315
0.31
0.28
0.01
0.02
5.88
17
85
1.42
0.8
0.315
0.31
0.28
0.01
0.02
5.88
18
90
1.50
0.8
0.315
0.31
0.28
0.01
0.02
5.88
19
95
1.58
0.8
0.315
0.31
0.28
0.01
0.02
5.88
20
100
1.67
0.8
0.315
0.31
0.28
0.01
0.02
5.88
21
105
1.75
0.8
0.315
0.31
0.28
0.01
0.02
5.88
22
110
1.83
0.8
0.315
0.31
0.28
0.01
0.02
5.88
23
115
1.92
0.8
0.315
0.31
0.28
0.01
0.02
5.88
24
120
2.00
0.9
0.354
0.31
0.32
0.05
0.12
35.64
25
125
2.08
0.8
0.315
0.31
0.28
0.01
0.02
5.88
26
130
2.17
0.9
0.354
0.31
0.32
0.05
0.12
35.64
27
135
2.25
0.9
0.354
0.31
0.32
0.05
0.12
35.64
28
140
2.33
0.9
0.354
0.31
0.32
0.05
0.12
35.64
29
145
2.42
0.9
0.354
0.31
0.32
0.05
0.12
35.64
30
150
2.50
0.9
0.354
0.31
0.32
0.05
0.12
35.64
31
155
2.58
0.9
0.354
0.31
0.32
0.05
0.12
35.64
32
160
2.67
0.9
0.354
0.31
0.32
0.05
0.12
35.64
33
165
2.75
1.0
0.394
0.31
0.35
0.09
0.22
65.39
34
170
2.83
1.0
0.394
0.31
0.35
0.09
0.22
65.39
35
175
2.92
1.0
0.394
0.31
0.35
0.09
0.22
65.39
36
180
3.00
1.0
0.394
0.31
0.35
0.09
0.22
65.39
37
185
3.08
1.0
0.394
0.31
0.35
0.09
0.22
65.39
38
190
3.17
1.1
0.433
0.31
0.39
0.13
0.32
95.15
39
195
3.25
1.1
0.433
0.31
0.39
0.13
0.32
95.15
40
200
3.33
1.1
0.433
0.31
0.39
0.13
0.32
95.15
41
205
3.42
1.2
0.472
0.31
0.43
0.17
0.42
124.91
42
210
3.50
1.3
0.512
0.31
0.46
0.20
0.52
154.66
43
215
3.58
1.4
0.551
0.31
0.50
0.24
0.61
184.42
44
220
3.67
1.4
0.551
0.31
0.50
0.24
0.61
184.42
45
225
3.75
1.5
0.590
0.31
0.53
0.28
0.71
214.17
46
230
3.83
1.5
0.590
0.31
0.53
0.28
0.71
214.17
47
235
3.92
1.6
0.630
0.31
0.57
0.32
0.81
243.93
48
240
4.00
1.6
0.630
0.31
0.57
0.32
0.81
243.93
49
245
4.08
1.7
0.669
0.31
0.60
0.36
0.91
273.69
50
250
4.17
1.8
0.708
0.31
0.64
0.40
1.01
303.44
51
255
4.25
1.9
0.748
0.31
0.67
0.44
1.11
333.20
52
260
4.33
2.0
0.787
0.31
0.71
0.48
1.21
362.96
53
265
4.42
2.1
0.827
0.31
0.74
0.52
1.31
392.71
54
270
4.50
2.1
0.827
0.31
0.74
0.52
1.31
1 392.71
55
275
4.58
2.2
0.866
0.31
0.78
0.56
1.41
1 422.47
56
280
4.67
2.3
0.905
0.31
0.81
0.60
1.51
1 452.22
Plate E -2.2
Page 7 of 18
RCFCD SYNTHETIC UNIT HYDROGRAPH METHOD
100 YEAR - 6 HOUR STORM EVENT
PROJECT: LA QUINTA RESORT SPECIFIC PLAN AMENC
CONCENTRATION POINT: 1
BY: JAMES R. BAZ DATE: 7/13/2009
EFFECTIVE RAIN (in)
EFFECTIVE
RAIN CALCULATION FORM
0.33
FLOOD VOLUME (tuft)
14311.03
DRAINAGE AREA -ACRES
UNIT TIME - MINUTES
LAG TIME - MINUTES
UNIT TIME - PERCENT OF LAG
TOTAL ADJUSTED STORM RAIN - INCHES
CONSTANT LOSS RATE -in/hr
LOW LOSS RATE - PERCENT
2.52
5
1.57
318.5
3.28
0.307
90%
TOTAL PERCOLATION RATE (cfs)
14192.70
0.00 cfs
4.78
Unit Time
Period
Time
Minutes Hours
Pattern
Percent
Plate E -5.9
Storm
Rain
in/hr
Loss Rate
in/hr
Max
Low
Effective
Rain
in/hr
Flood
Hydrograph
Flow
cfs
Required
Storage
cf
57_
285
4.75
2.4 .
0.945
0.31
0.85
0.64
1.61
481.98
58
290
4.83
2.4
0.945
0.31
0.85
0.64
1.61
481.98
59
295
4.92
2.5 .
0.984
1 0.31
0.89
0.68
1.71
511.74
60
300
5.00
2.6
1.023
0.31
0.92
0.72
1.80
541.49
61
305
5.08
3.1
1.220
0.31
1.10
0.91
2.30
690.27
62
310
5.17
3.6
1.417
0.31
1.28
1.11
2.80
839.05
63
315
5.25
3.9
1.535
0.31
1.38
1.23
3.09
928.32
64
320
5.33
.4.2
1.653
0.31
1.49
1.35
3.39
1017.59
65
325
5.42
4.7. _
1.850
0.31
1.66
1.54
3.89
1166.37
66
330
5.50
5.6
2.204
0.31
1.98.
1.90
4.78
1434.18
67 .
335
5.58
1.9
0.748
0.31
0.67
0.44
1.11
333.20
68
340
5.67
0.9
0.354
0.31
0.32
0.05
0.12
35.64.
69
345
5.75
0.6
0.236
0.31
0.21
0.02
0.06
17.85
70
350
5.83
0.5
0.197
0.31
0.18
0.02
0.05
14.88
71
355
5.92
0.3
0.118
0.31
0.11
0.01
0.03
8.93
72
1 360
6.00
0.2
0.079
0.31
0.07
0.01
1 0.02
5.95
EFFECTIVE RAIN & FLOOD VOLUMES SUMMARY
i
EFFECTIVE RAIN (in)
1.56
FLOOD VOLUME (acft)
0.33
FLOOD VOLUME (tuft)
14311.03
REQUIRED STORAGE (acft)
0.33
REQUIRED STORAGE (tuft)
14192.70
PEAK FLOW RATE (cfs)
4.78
1
Plate E -2.2
Page 8 of 18
RCFCD SYNTHETIC UNIT HYDROGRAPH METHOD
100 YEAR - 24 HOUR STORM EVENT
PROJECT: LA QUINTA RESORT SPECIFIC PLAN AMEND
CONCENTRATION POINT: 1
BY: JAMES R. BAZ DATE: 7/13/2009 _
EFFECTIVE RAIN CALCULATION FORM
DRAINAGE AREA -ACRES 2.520
UNIT TIME- MINUTES 15
LAG TIME - MINUTES 1.57
UNIT TIME - PERCENT OF LAG 955.4
TOTAL ADJUSTED STORM RAIN- INCHES 4.38
CONSTANT LOSS RATE - in/hr n/a
VARIABLE LOSS RATE (AVG) in/hr 0.3071
MINIMUM LOSS RATE (for var. loss) - in/hr 0.154
LOW LOSS RATE - DECIMAL 0.90
C 0.00284
PERCOLATION RATE cfs 0.00
Unit Time
Period
Time
Minutes Hours
Pattern
Percent
Plate E -5.9
Storm
Rain
in/hr
Loss Rate
in/hr
Max Low
Effective
Rain
in/hr
Flood
Hydrograph
Flow
cis
Required
Storage
cf
1
.15
0.25
0.2
0.035.
0.542
0.032
0.004
0.01
7.95
2.
30
0.50
0.3
0.053
0.536
0.047
0.005
0.01
11.92
3
45
0.75
0.3
0.053
0.530
0.047
0.005
0.01
11.92
4 ..
.60
1.00
0.4
0.070
0.524
0.063
0.007
0.02
15.89
5
75
1.25
0.3
0.053
0.517
0.047
0.005
0.01
11.92
6
90
1.50
0.3
0.053
0.511
0.047
0.005
0.01
11.92
7-
105
1.75
0.3
0.053
0.505
0.047
0.005
0.01
11.92
8
120
2.00
0.4
0.070
0.499
0.063
0.007.
0.02
15.89
9
135
2.25
0.4
0.070
0.493
0.063
0.007
0.02
15.89
10
150
2.50
0.4
0.070
0.487
0.063
0.007
0.02
15.89
11
165
2.75
0.5
0.088
0.481
0.079
0.009
0.02
19.87
12.
180
3.00
0.5
0.088
0.475
0.079
0.009
0.02
19.87
13
195
3.25
0.5
0.088
0.469
0.079
0.009
0.02
19.87
14
210
3.50
0.5
0.088
0.463
0.079
0.009
0.02
19.87
15
225
3.75
0.5
0.088
0.458
0.079
0.009
0.02
19.87
16
240
4.00
0.6
0.105
0.452
0.095
0.011
0.03
23.84
17
255
4.25
0.6
0.105
0.446
0.095
0.011
0.03
23.84
18
.270
4.50
0.7
0.123
0.440
0.110
0.012
0.03
27.81
19
285
4.75
0.7
0.123
0.435
0.110
0.012
0.03
27.81
20
300
5.00
0.8
0.140
0.429
0.126
0.014
0.04
31.79
21
315
5.25
0.6
0.105
0.424
0.095
0.011
0.03
23.84
22
330
5.50
0.7
0.123
0.418
0.110
0.012
0.03
27.81
23
345
5.75.
0.8
0.140
0.413
0.126
0.014
0.04
31.79
24
360
6.00
1 0.8
0.140
0.407
0.126
0.014
0.04
31.79
25
375
6.25
0.9
0.158
0.402
0.142
0.016
0.04
35.76
26
390
6.50
0.9
0.158
0.396
0.142
0.016
0.04
35.76
27
405
6.75
1.0
1 0.175
0.391
0.158
0.018
0.04
39.74
28
420
7.00
1.0
0.175
0.386
0.158
0.018
0.04
39.74
29
435
7.25
1.0
0.175
0.381
0.158
0.018
0.04
39.74
30
450
7.50
1.1
0.193
0.375
0.173
0.019
0.05
43.71
31
465
7.75
1.2
0.210
0.370
0.189
0.021
0.05
47.68
32
480
8.00
1.3
0.228
0.365
0.205
0.023
0.06
51.66
33
495
8.25
1.5
0.263
0.360
0.237
0.026
0.07
59.60
34
510
8.50
1.5
0.263
0.355
0.237
0.026
1 0.07
59.60
35
525
8.75
1.6
0.280
0.350
0.252
0.028
0.07
63.58
36
540,
9.00
1.7
0.298
0.345
0.268
0.030
0.08
67.55
37
555
9.25
1.9
0.333
0.340
0.300
0.033
0.08
75.50
38
570
9.50
2.0
0.350
0.335
0.315
0.015
0.04
33.98
39
585
9.75
21
0.368
0.331.
0.331
0.037
0.09
84.59
40
600
10.00
2.2
0.385
0.326
0.347
0.060
0.15
135.10
41
615
10.25
1.5.
0.263
0.321
0.237
0.026
0.07
59.60
42
630
10.50
1.5
0.263
0.317
0.237
0.026
0.07
59.60
43
645
1 10.75
2.0
0.350
0.312
0.315
0.039
0.10
87.32
44
660
11.00
2.0
0.350
0.307
0.315
0.043
0.11
97.67
45
675
11.25
1.9
0.333
0.303
0.300
0.030
0.08
68.18
46
690
11.50
1.9
0.333
0.298
0.300
0.035
0.09 -
78.32
47
705
11.75
1.7
0.298
0.294
0.268
0.004
0.01
8.87
48
720
12.00
1.8
0.315
0.290
0.284
0.026.
0.07
58.52
49
735
12.25
2.5
0.438
0.285
0.394
0.153
0.38
346.47
50
750
12.50
2.6
0.456
0.281
0.410
0.175
0.44
395.89
51
765
12.75
2.8
0.491
0.277
0.442
0.214
0.54
484.94
52
780
13.00
2.9
0.508
0.273
0.457
0.236
0.59
534.14
53
795
13.25
3.4
0.596
0.268
0.536
0.327
0.82
742.16
54
810
13.50
3.4
0.596
0.264
0.536
0.331
0.83
751.38
55
825
13.75
2.3
1 0.403
0.260
0.363
0.143
0.36
323.40
56
840
14.00
2.3
0.403
0.256
0.363
0.147
0.37
332.39
57
855
14.25
2.7
0.473
0.252
0.426
0.221
0.56
500.20
58
870
14.50
2.6
0.456
0.249
0.410
0.207
0.52
469.21
59
885
14.75
2.6
0.456
0.245
0.410
0.211
0.53
477.83
60
900
15.00
2.5
0.438
0.241
0.394
0.197
0.50
446.59
61
915
15.25
2.4
0.420
0.237
0.378
0.183
0.46
415.22
62
930
15.50
2.3
0.403
0.234
0.363
0.169
0.43
1 383.72
63
945
15.75
1.9
0.333
0.230
0.300
0.103
0.26
232.89
64
960
16.00
1.9
0.333
0.227
0.300
0.106
0.27
240.87
65
975
16.25
0.4
0.070
0.223
0.063
0.007
0.02
15.89
66
990
16.50
0.4
0,070
0.220
0.063
0.007
0.02
15.89
67
1005
16.75
0.3
0.053
0.216
0.047
0.005
0.01
11.92
;r
MENT NO. 6, F
u
ti
1
Plate E -2.2
Page 9 of 18
i
r
t
RCFCD SYNTHETIC UNIT HYDROGRAPH METHOD
100 YEAR - 24 HOUR STORM EVENT
PROJECT: LA OUINTA RESORT SPECIFIC PLAN AMEN[
CONCENTRATION POINT: 1
BY: JAMES R. BAZ DATE: 7/1312009
EFFECTIVE
RAIN CALCULATION FORM
DRAINAGE AREA -ACRES 2.520
UNIT TIME - MINUTES 15
LAG TIME - MINUTES ` 1.57
UNIT TIME - PERCENT OF LAG 955.4
TOTAL ADJUSTED STORM RAIN- INCHES 4.38
CONSTANT LOSS RATE - in/hr n/a
VARIABLE LOSS RATE (AVG) in/hr 0.3071
MINIMUM LOSS RATE (for var. loss) - in/hr 0.154
LOW LOSS RATE - DECIMAL 0.90
C 0.00284
PERCOLATION RATE cis 0.00
Unit Time
Period
Time
Minutes Hours
t
Pattern
Percent
Plate E -5.9
Storm
Rain
in/hr
Loss Rate
in/hr
Max Low
Effective
Rain
in/hr
Flood
Hydrograph
Flow
cis
Required
Storage
cf
68 =
1020
17.00
0.3
0.053
.0.213
0.047
0.005
0.01
11.92
69
1035
17.25
0.5
.0.088
0.210
0.079
0.009
0.02
19.87
70
1050
17.50
0.5
0.088
0.207
0.079
0.009
0.02.
19.87
71
.1065
17.75
0.5
0.088
0.204
0.079
0.009
0.02
19.87
72
1080
18.00.
0.4
0.070
0.201
0.063
0.007
0.02
15.89
73
1095 -
18.25
0.4
0.070.
0.198
0.063
0.007
0.02
15.89
74
1110
18.50
0.4
0.070
0.195
0.063
0.007
0.02
15.89
75
1125
18.75
0.3
0.053
0.192
0.005
0.01
11.92
76
1140
19.00
0.2
0.035
0.189
0.004
0.01
7.95
77
1.155
19.25.
0.3
0.053
0.187
0.005
0.01
11.92
78,
1170
19.50.
0.4
0.070
0.184
0.007
0.02
15.89
79
1185
19.75
0.3
0.053
0.182
M04
0.005.
0.01
11.92
80
1200
20.00
0.2
0.035
0.179
0.004
.0.01
7.95
81
1215.
20.25
0.3
0.053
0.177
0.005
0.01
11.92
82
1230
20.50,
0.3
0.053
0.174
0.005
0.01
11.92
83 ..
1245
20.75
0.3
0.053.
0.172
.
0.005
0.01
11.92
84
1260
21.00
0.2
0.035
0.170
0.032
0.004
0.01
7.95
85
1275
21.25,
0.3
0.053
o.iF8-7
0.047
0.005
0.01
11.92
86
1290
21.50
0.2
0.035
0.166
0.032
0.004
0.01
7.95
87
1305
21.75
0.3
0.053
0.164
0.047
0.005
0.01
11.92
88
1320
22.00
0.2
0.035
0.163
0.032
0.004
0.01
7.95
89
1335
22.25
0.3
0.053
0.161
0.047
0.005
0.01
11.92
90
1350
22.50
0.2
0.035
0.160
0.032
0.004
0.01
7.95
91
1365
22.75
0.2
0.035
0.158
0.032
0.004
0.01
7.95
92
1380
23.00
0.2
0.035
0.157
0.032
0.004
0.01
7.95
93
1395
23.25
0.2
0.035
0.156
.0.032
0.004
0.01
7.95
94
1410
23.50 _
0.2
0.035
0.155
0.032
0.004
0.01
7.95
95
1425
23.75
0.2
0.035
0.154
0.032
0.004
0.01
7.95
96
1440
24.00
0.2
0.035
0.154
0.032
0.004
0.01
7.95
MENT NO. 6, F
E
Plate E -2.2
Page 10 of 18
EFFECTIVE RAIN & FLOOD VOLUMES SUMMARY
t
'
EFFECTIVE RAIN (in)
1.03
FLOOD VOLUME (acft)
0.22
FLOOD VOLUME (cuff)'
9449.06
REQUIRED STORAGE (acft)
0.22
'
REQUIRED STORAGE (tuft)
9370.93
PEAK FLOW (cis) _
0.83 _
MENT NO. 6, F
E
Plate E -2.2
Page 10 of 18
N
1
TKC JOB # 2017110600
.100 YEAR -.q 1-101-1R STORM FVFNT
TIME
UNIT (min)
PERIOD
FLOW
IN
cfs
VOLUME
IN
cult
TOTAL IN
BASIN
cult
PERC
OUT
cult
TOTAL IN
BASIN
cult
BASIN
DEPTH
ft
BALANCE IN
BASIN
cult acre -ft
1
5
0.29
87
87
0
87
87
0.00
2
10
0.29
87
175
0
175
175
0.00
3
15
0.13
38
213
01
213
213
0.00
4
20
0.46
137
350
0
350
350
0.01
5
25
0.46
137
486
0
486
486
0.01
6
30
0.70
210
697
0
697
697
0.02
7
35
0.46
137
833
0
833
833
0.02
8
40
0.70
210
1,044
0
1,044
1,044
0.02
9
45
0.70
210
1,254
0
1,254
1,254
0.03
10
50
0.46
137
1,391
0
1,391
1,391
0.03
11
55
0.54
161
1,552
0
.1,552
1,552
0.04
12
60
0.70
210
1,762
0
1,762
1,762
0.04
13
65
1.03
309
2,071
0
2,071
2,071
0.05
14
70
1.03
309
2,380
0
2,380
2,380
0.05
15
75
1.03
309
2,688
01
2,688
2,688
0.06
16
80
0.87
260
2,948
0
2,948
2,948
0.07
17
85
1.36
407
3,355
0
3,355
3,355
0.08
18
90
1.44
432
3,787
0
3,787
3,787
0.09
19
95
1.19
358
4,144
0
4,144
4,144
0.10
20
100
1.44
432
4,576
0
4,576
4,576
0.11
21
105
1.93
579
5,155
0
5,155
5,155
0.12
22
110
1.77
530
5,685
0
5,685
5,685
0.13
23
115
1.60
481
6,166
0
6,166
6,166
10.14
24
120
1.68
505
6,671
0
6,671
6,671
0.15
25
125
1.77
530
7,201
0
7,201.
7,201
0.17
26
130
2.67
800
8,002
0
8,002
8,002
0.18
27
135
3.32
997
8,999
0
8,999
8,999
0.21
28
140
2.09
628
9,627
0
9,627
9,627
0.22
29
145
4.80
1,440
11,067
0
11,067,
11,067
0.25
30
150
5.21
1,563
12,629
0
12,629
12,629
0.29
31
155
5.95
1,784
14,413
0
14,413
14,413
0.33
32
160
4.06
1,218
15,631.
0
15,631
15,631
0.36
33
165
0.87
260
15,891
0
15,891
15,891
0.36
34
170
0.70
210
16,101
0
16,101
-
16,101
0.37
35
175
0.70
210
16,312
0
16,312
16,312
0.37
36
180
0.05
15
16,326
0
16,326
16,326
0.37
Basin Depth Analysis
Page 14 of 18
' 1
TKC JOB # 2017110600
100 YEAR - 6 HOUR STORM EVENT
TIME
UNIT (min)
PERIOD
FLOW
IN
cfs
VOLUME
IN
cuff
TOTAL IN
BASIN
cuff
PERC
OUT
cult
TOTAL IN
BASIN
cult
BASIN
DEPTH
ft
BALANCE IN
BASIN
cuff acre -ft
1
5
0.05
15
15
0
15
15
0.00
2
10
' 0.06
18
33
0
33
33
0.00
3
15
0.06
18
51
0
51
51
0.00
4
20
0.06
18
68
0
68
68
0.00
5
25
0.06
18
86
0
86
-
86
0.00
6
30
0.07
21
107
0
107
107
0.00
7
35
0.07
21
128
0
128
-
128
0.00
8
40
0.07
21
149
0
149
149
0.00
9
45
0.07
21
170
0
170
170
0.00
10
50
0.07
21
190
0
190
190
0.00
11
55
0.07
21
211
0
211
211
0.00
12
60
0.02
6
217
0
217
217
0.00
13
65
0.02
6
223
0
223
223
0.01
14
70
0.02
6
229
0
229
229
0.01
15
75
0.02
6
235
0
235
235
0.01
16
80
0.02
6
241
0
241
241
0.01
17
85
0.02
6
247
0
247
247
0.01
18
90
0.02
6
252
01
252
252
0.01
19
95
0.02
6
258
0
258
258
0.01
20
100
0.02
6
264
0
264
-
264
0.01
21
105
0.02
6
270
0
270
-
270
0.01
22
110
0.02
6
276
0
276
-
276
0.01
23
115
0.02
6
282
0
282
-
282
0.01
24
120
0.12
36
317
0
317
-
317
0.01
25
125
0.02
6
323
0
323
-
323
0.01
26
130
0.12
36
359
0
359
359
0.01
27
135
0.12
36
395
0
395
395
0.01
28
140
0.12
36
430
0
430
430
0.01
29
145
0.12
36
466
0
466
466
0.01
30
150
0.12
36
502
0
502
502
0.01
31
155
0.12
36
537
0
537
537
0.01
32
160
0.12
36
573
0
573
573
0.01
33
165
0.22
65
638
0
638
-
638
0.01
34
170
0.22
65
704
0
704
704
0.02
35
175
0.22
65
769
0
769
769
0.02
36
180
0.22
65
834
0
834
834
0.02
37
185
0.22
65
900
0
900
900
0.02
38
190
0.32
95
995
0
995
995
0.02
39
195
0.32
95
1,090
0
1,090
1,090
0.03
40
200
0.32
95
1,185
0
1,185
1,185
0.03
41
205
0.42
125
1,310
0
1,310
-
1,310
0.03
42
210
0.52
155
1,465
0
1,465
-
1,465
0.03
43
215
0.61
184
1,649
0
1,649
-
1,649
0.04
44
220
0.61
184
1,834
0
1,834
-
1,834
0.04
45
225
0.71
214
2,048
0
2,048
-
2,048
0.05
46
230
0.71
214
2,262
0
2,262
-
2,262
0.05
47
235
0.81
244
2,506
0
2,506
-
2,506
0.06
48
240
0.81
244
2,750
0
2,750
-
2,750
0.06
49
245
0.91
274
3,024
0
3,024
-
3,024
0.07
50
250
1.01
303
3,327
0
3,327
-
3,327
0.08
51
255
1.11
333
3,660
0
3,660
-
3,660
0.08
52
260
1.21
363
4,023
0
4,023
-
4,023
0.09
53
265
1.31
393
4,416
0
4,416
-
4,416
0.10
54
270
1.31
393
4,809
0
4,809
4,809
0.11
55
275
1.41
422
5,231
0
5,231
1 -
5,231
0.12
Basin Depth Analysis
Page 15 of 18
1'
TKC JOB # 2017110600
inn YEAR - 6 HOUR STORM EVENT
TIME
UNIT (min)
PERIOD
FLOW
IN
cfs
VOLUME
IN
cult
TOTAL IN
BASIN
cult-
PERC
OUT
cult
TOTAL IN
BASIN
cult
BASIN
DEPTH
ft
BALANCE IN
BASIN
cult acre -ft
56
280
1.51
452
5,683
0
5,683
5,683
0.13
57
285
1.61
482
6,165
0
6,165
6,165
0.14
58
290
1.61
482
6,647
0
6,647
6,647
0.15
59
295.
1.71
512
7,159
0
7,159
7,159
0.16
60
300
1.80
541
7,700
0
7,700
7,700
0.18
61
305,
2.30
690
8,391
0
8,391
8,391
0.19
62
310
2.80.
839
9,230
0
9,230
9,230
0.21
.63.
315
3.09
928
10,158
0
10,158
10,158
0.23
64
320
3.39
1,018
11,176
0
11,176
11,176
0.26
65
325
3.89
1,166
12,342
0
12,342
12,342
0.28
66
330
4.78
1,434
13,776
0
13,776
13,776
0.32
67
335
1.11
333
14,109
0
14,109
14,109
0.32
68
340
0.12
36
14,145
0
14,145
14,145
0.32
69
345
0.06
18
14,163
0
14,163
14,163
0.33
70
350
0.05
15
14,178
0
14,178
14,178
0.33
71,
355
0.03
9
14,187
0
_ 14,187
14,187
0.33
72
360
0.02
6
14,193
0
14,193
14,193
0.33
i
J
Basin Depth Analysis
Page 16 of 18
1
TKC JOB # 2017110600
100 YEAR - 24 HOUR STORM EVENT
TIME
UNIT (min)
PERIOD
FLOW
IN
cfs
VOLUME
IN
cult
PERC
OUT
cult
TOTAL IN
BASIN
cult
BASIN
DEPTH
ft
BALANCE IN
BASIN
cult acre -ft
1
15
0.01
8
A32
0
8
8
0.00
2
30
0.01
12
0
20
20
0.00
3
45
0.01
12
0
32
32
0.00
4
60
0.02
16
48
0
48
48
0.00
5
75
0.01
12
60
0
60
60
0.00
6-
90
0.01
12
72
0
72
72
0.00
7
105
0.01
12
83
0
83
83
0.00
8
120
0.02
16
99
0
99
99
0.00
9
135
0.02
16
115
0
115
115
0.00
10
150
0.02
16
131
0
131
131
0.00
11
165
0.02
20
151
0
151
151
0.00
12
180
0.02
20
171
0
171
171
0.00
13
195
0.02
20
191
0
191
191
0.00
14
210
0.02
20
211
0
211
211
0.00
15
225
0.02
20
230
0
230
230
0.01
16
240
0.03
24
254
0
254
254
0.01
17
255
0.03
24
278
0
278
278
0.01
18
270
0.03
28
306
0
306
306
0.01
19
285
0.03
28
334
0
334
334
0.01
20
300
0.04
32
366
0
366
366
0.01
21
315
0.03
24
389
0
389
389
0.01
22
330
0.03
28
417
0
417
417
0.01
23
345
0.04
32
449
0
449
449
0.01
24
360.
0.04
32
481
0
481
481
0.01
25
375
0.04
36
517
0
517
517
0.01
26
390
0.04
36
552
0
552
552
0.01
27
405
0.04
40
592
0
592
592
0.01
28
420
0.04
40
632
0
632
632
0.01
29
435
0.04
40
672
0
672
672
0.02
30
450
0.05
44
715
0
715
715
0.02
31
465
0.05
48
763
0
763
763
0.02
32
480
0.06
52
815
0
815
815
0.02
33
495
0.07
60
874
0
874
874
0.02
34
510
0.07
60
934
0
934
934
0.02
35
525
0.07
64
997
0
997
997
0.02
36
540
0.08
68
1,065
0
1,065
1,065
0.02
37
555
0.08
75
1,140
0
1,140
1,140
0.03
38
570
0.04
34
1,174
0
1,174
1,174
0.03
39
585
0.09
85
1,259
0
1,259
1,259
0.03
40
600
0.15
135
1,394
0
1,394
1,394
0.03
41
615
0.07
60
1,454
0
1,454
1,454
0.03
42
630
0.07
60
1,513
0
1,513
1,513
0.03
43
645
0.10
87
1,601
0
1,601
1,601
0.04
44
660
0.11
98
1,698
0
1,698
1,698
0.04
45
675
0.08
68
1,766
0
1,766
1,766
0.04
46
690
0.09
78
1,845
0
1,845
11845
0.04
47
705
0.01
9
1,854
0
1,854
1,854
0.04
48
720
0.07
59
1,912
0
1,912
1,912
0.04
49
735
0.38
346
2,259
0
2,259
2,259
0.05
50
750
0.44
396
2,655
0
2,655
2,655
0.06
51
765
0.54
485
3,139
0
3,139
3,139
0.07
52
780
0.59
534
3,674
0
3,674
3,674
0.08
53
795
0.82
742
4,416
0
4,416
4,416
0.10
54
810
0.83
751
5,167
0
5,167
5,167
0.12
55
825
0.36
323
5,491
0
5,491
5,491
0.13
56
840
0.37
332
5,823
0
5,823
5,823
0.13
57
855
0.561
500
6,323
01
6,323
6,323
0.15
58
870
0.521
469
6,792
1 01
6,792
6,792
0.16
Basin Depth Analysis
Page 17 of 18
t 1
TKC JOB # 2017110600
10O YEAR - 94 HOUR STORM EVENT
TIME
UNIT (min)
PERIOD
FLOW
IN
cfs
VOLUME
IN
cult
PERC
OUT
cult
TOTAL IN
BASIN
cult
BASIN
DEPTH
ft
BALANCE IN
BASIN
cult acre -ft
59
885
0.53
478
48,'1,
0
7,270
7,270
0.17
60
900
0.50
447
0
7,717
7,717
0.18
61
915
0.46
415
0
8,132
8,132
0.19
62
930
0.43
384
8,516
0
8,516
8,516
0.20
63
945
0.26
233
8,749
0
8,749
8,749
0.20
64
960
0.27
241
8,989
0
8,989
8,989
0.21
65
975
0.02
16
9,005
0
9,005
9,005
0.21
66
990
0.02
16
9,021
0
9,021
9,021
0.21
67
1005
0.01
12
9,033
0
9,033
9,033
0.21
68
1020
0.01
12
9,045
0
9,045
9,045
0.21
69
1035
0.02
20
9,065
0
9,065
9,065
0.21
70
1050
0.02
20
9,085
0
9,085
9,085
0.21
71
1065
0.02
20
9,105
0
9,105
9,105
0.21
72
1080
0.02
16
9,121
0
9,121
9,121
0.21
73
1095
0.02
16.
9,136
0
9,136
9,136
0.21
74
1110
0.02
16
9,152
0
9,152
9,152
0.21
75
1125
0.01
12
9,164
0
9,164
9,164
0.21
76
1140
0.01
8
9,172
0
9,172
9,172
0.21
77
1155
0.01
12
9,184
0
9,184
9,184
0.21
78
1170
0.02
16
9,200
0
9,200
9,200
0.21
79
1185
0.01
12
9,212
0
9,212
9,212
0.21
80
1200
0.01
8
9,220
0
9,220
9,220
0.21
81
1215
0.01
12
9,232.1
0
9,232
9,232
0.21
82
1230
0.01
12
9,244
0
9,244
9,244
0.21
83
1245
0.01
12
9,256
0
9,256
9,256
0.21
84
1260
0.01
8
9,264
0
9,264
9,264
0.21
85
1275
0.01
12
9,276
0
9,276
9,276
0.21
86
1290
0.01
8
9,284
0
9,284
9,284
0.21
87
1305
0.01
12
9,295
0
9,295
9,295
0.21
88
1320
0.01
8
9,303
0
9,303
9,303
0.21
89
1335
0.01
12
9,315
0
9,315
9,315
0.21
90
1350
0.01
8
9,323
0
9,323
9,323
0.21
91
1365
0.01
8
9,331
0
9,331
9,331
0.21
92
1380
0.01
8
9,339
0
9,339
9,339
0.21
93
1395
0.01
8
9,347
0
9,347
9,347
0.21
94
1410
1 0.011
8
9,355
1 0
9,355
9,355
1 0.21
95
1425
1 0.01
8
9,363
1 0
9,363
1 9,3631
0.21
96
1 1440
1 0.011
8
9,371
1 0
9,371
1 9,371
1 0.22
Basin Depth Analysis
Page 18 of 18
A._
B
C
D
1.
RCFCD SYNTHETIC UNIT HYDROGRAPH
2
DATA INPUT.SHEET
3
4
WORKSHEET PREPARED BY:
JAMES R. BAZUA,!
P.E.
5
6
PROJECT NAME
LA QUINTA RESORT
SPECIFIC PLAN AMENDMENT
.7
TKC JOB #
20171106001
8,
9
CONCENTRATION POINT DESIGNATION
.1 -
10
AREA DESIGNATION
CONFERENCE EXPANSION
11
12
TRIBUTARY AREAS
ACRES
13
14
COMMERCIAL
10.7
15
PAVING /HARDSCAPE
.16
SF-1 ACRE
17
SF - 1/2 ACRE
18
SF - 1/4 ACRE
19
MF -CONDOMINIUMS'
3.6
20
IMF - APARTMENTS
21
MOBILE HOME PARK
22
LANDSCAPING
1.1
23
RETENTION BASIN ,
24
GOLF COURSE
-
25
MOUNTAINOUS
26
LOW LOSS RATE (PERCENT)
- 90%
.
27
28
LENGTH OF WATERCOURSE (L)
1000
29
LENGTH TO POINT OPPOSITE CENTROID (Lca)
430
30
,
.31
ELEVATION OF HEADWATER
49
32
ELEVATION OF CONCENTRATION POINT
°F 44
33
.34
AVERAGE MANNINGS'N' VALUE
0.02
35
36
STORM FREQUENCY (YEAR)
100
37
38
POINT RAIN
39
3 -HOUR
2.7.1
40
6 -HOUR
3.28
41
24 -HOUR
4.38
42
43
BASIN CHARACTERISTICS:
ELEVATION
AREA
44
45
46
47
48
49
50
51
52
PERCOLATION RATE (in /hr)
53
54
DRYWELL DATA
55
NUMBER USED
56
PERCOLATION RATE cfs
RCFCD SYNTHETIC UNIT HYDROGRAPH METHOD PROJECT:
BASIC DATA CALCULATION FORM TKC JOB #
SHORTCUT METHOD BY
LA QUINTA RESORT SPECIFIC PLAN AMENDMENT NO. 6, PLAI
2017110600
_S R. BAZUA, P.E. DATE 7/13/2009
3 -HOUR,
PHYSICAL DATA
24 -HOUR
EFFECTIVE RAIN (in)
2.05
[11 CONCENTRATION POINT,
1.52
FLOOD VOLUME (cu -ft)
(acre -ft)
114,425
2.63
1
84,784
1.95
1`21 AREA DESIGNATION
113,479
2.61
109,539
2.51
CONFERENCE EXPANSION
PEAK FLOW (cfs)
[31 AREA - ACRES
30.52
6.23
MAXIMUM WSEL (ft)
15.400
4 L -FEET
1000
5 L -MILES
0.189
[61 La -FEET
430.00
7 La -MILES
0.081
[81 ELEVATION OF HEADWATER
49
9 ELEVATION OF CONCENTRATION POINT
44
10 H -FEET
5
11 S- FEET /MILE
26.4
(121 S^0.5
5.14
13 L'LCA/S^0.5
0.003
[141 AVERAGE MANNINGS'N'
0.02
f 51 LAG TIME -HOURS
0.05
1161 LAG TIME- MINUTES
3.2
[171100% OF LAG- MINUTES
3.2
[181200% OF LAG-MINUTES
6.3
[191 UNIT TIME - MINUTES 100% -200% OF LAG
5
[24] TOTAL PERCOLATION RATE (cfs)
0.00
RAINFALL
DATA
[7] SOURCE
[2] FREQUENCY -YEARS 100
[3) DURATION:
3 -HOURS
6 -HOURS
24 -HOURS
[41
POINT
RAIN
INCHES
Plate E -5.2
[5]
AREA
[6]
(7)
AVERAGE
POINT
RAIN
INCHES
[81
POINT
RAIN
INCHES
Plate E -5.4
191
AREA
[10]
[11)
AVERAGE
POINT
RAIN
INCHES
[12]
POINT
RAIN
INCHES
Plate E -5.6
[131
AREA
[141
[151
AVERAGE
POINT
RAIN
INCHES
2.71
15.400
1.00
2.71
3.28
15.400
1.00
3.28
4.38
15.400
1.00
4.38
0.00
0.00
0.00
0.00
0.00
0.00
0.00.
0.00
0.00
0.00
1
0.00
0.00
0.00
0.00
0.00
0.00
1
0.00
0.00
SUM [5] 15.4 SUM [71
[16] AREA ADJ FACTOR
_[1 71 ADJ AVG POINT RAIN
2.71
SUM [9)
15.40 SUM It 1]
3.28
SUM [131 1 15.40 SUM If 5]
4.38
1.000
1.000
1.000
2.71
3.28
4.38
STORM EVENT SUMMARY
DURATION
3 -HOUR,
6 -HOUR
24 -HOUR
EFFECTIVE RAIN (in)
2.05
1.98
1.52
FLOOD VOLUME (cu -ft)
(acre -ft)
114,425
2.63
110,452
2.54
84,784
1.95
REQUIRED STORAGE (cu -ft)
(acre -ft)
113,479
2.61
109,539
2.51
84,083
1.93
PEAK FLOW (cfs)
37.64
30.52
6.23
MAXIMUM WSEL (ft)
Plate E -2.1
Page 2 of 18
M M M M
RCFCD SYNTHETIC UNIT HYDROGRAPH METHOD
PROJECT LA QUINTA RESORT SPECIFIC PLAN AMENDMENT NO. 6, PLANNING
CONCENTRATION POINT: 1
BY MES R. BAZUA, P.E. DATE 7/13/2009
DJUSTED LOSS RATE -
SOIL
GROUP
Plate C -1
LAND USE
RI
NUMBER
Plate E-6.11
PERVIOUS
AREA
INFILTRATION
RATE
(in /hr)
Plate E -6.2
DECIMAL
PERCENT
OF AREA
IMPERVIOUS
Plate E -6.3
ADJUSTED
INFILTRATION
RATE
(in /hr)
AREA
AVERAGE
ADJUSTED
INFILTRATION
RATE
(in /hr)
A
COMMERCIAL
32
0.74
90%
0.14
10.70
0.695
0.0977
A
PAVING /HARDSCAPE
32
0.74
100%
0.07
0.00
0.000
0.0000
A
SF - 1 ACRE
32
0.74
20%
0.61
0.00
0.000
0.0000
A
SF - 1/2 ACRE
32
0.74
40%
0.47
0.00
0.000
0.0000
A
SF - 1/4 ACRE
32
0.74
50%
0.41
0.00
0.000
0.0000
A
MF - CONDOMINIUMS
32
0.74
65%
0.31
3.60
0.234
0.0718
A
MF - APARTMENTS
32
0.74
80%
0.21
0.00
0.000
0.0000
A
MOBILE HOME PARKS
32
0.74
75%
0.24
0.00
0.000
0.0000
A
LANDSCAPING
32
0.74
0%
0.74
1.10
0.071
0.0529
A
RETENTION BASINS
32
0.74
0%
0.74
0.00
0.000
0.0000
A
GOLF COURSE
32
0.74
0%
0.74
0.00
0.000
0.0000
D
MOUNTAINOUS
93
0.95
90%
0.18
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
SUM 15.4 SUMI 0.2223
VARIABLE LOSS RATE CURVE 24 -HOUR STORM ONLY)
Fm= 0.111168182
C= 0.00206
Ft= C(24- (T /60)) ^1.55 = 0.00206 (24- (T /60)) ^1.55 + 0.11 in /hr
LOW LOSS RATE (80 -90 PERCENT) = 90%
Where: 1 ?7 7
T =Time in minutes. To get an average value for each unit time period, Use T =1/2 the unit time for the first time period,
T =1 1/2 unit time for the second period, etc.
Plate E -2.1
Page 4 of 18
RCFCD SYNTHETIC UNIT HYDROGRAPH METHOD
100 YEAR - 3 HOUR STORM EVENT
PROJECT: LA QUINTA RESORT SPECIFIC PLAN AMENDMENT NO. 6, P
CONCENTRATION POINT: 1
BY: IES R. BAZUA, DATE 7/13/2009
EFFECTIVE
RAIN CALCULATION FORM
DRAINAGE AREA -ACRES 15.40
UNIT TIME - MINUTES 5
LAG TIME - MINUTES 3.17
UNIT TIME - PERCENT OF LAG 157.8
TOTAL ADJUSTED STORM RAIN - INCHES 2.71
CONSTANT LOSS RATE -in/hr 0.22
LOW LOSS RATE - PERCENT 90%
TOTAL PERCOLATION RATE (cfs) 0.00 cfs
Unit Time
Period
Time
Minutes Hours
Pattern
Percent
Plate E -5.9
Storm
Rain
in /hr
Loss Rate
in/hr
Max Low
Effective
Rain
in/hr
Flood
Hydrograph
Flow
cfs
Required
Storage
cf
1
5
0.08
1.3
0.423
0.22
0.38
0.20
3.09
925.96
2
10
0.17
1.3
0.423
0.22
0.38
0.20
3.09
925.96
3
15
0.25
1.1
0.358
0.22
0.32
0.14
2.08
625.47
4
20
0.33
1.5
0.488
0.22
0.44
0.27
4.09
1226.44
5
25
0.42
1.5
0.488
0.22
0.44
0.27
4.09
1226.44
6
30
0.50
1.8
0.585
0.22
0.53
036
5.59
1677.17
7
35
0.58
1.5
0.488
0.22
0.44
0.27
4.09
1226.44
8
40
0.67
1.8
0.585
0.22
0.53
0.36
5.59
1677.17
9
45
0.75
1.8
0.585
0.22
0.53
0.36
5.59
1677.17
10
50
0.83
1.5
0.488
0.22
0.44
0.27
4.09
1226.44
11
55
0.92 _
1.6
0.520
0.22
0.47
0.30
4.59
1376.68
12
60
1.00
1.8
0.585
0.22
0.53
0.36
5.59
1677.17
13
65
1.08
2.2
0.715
0.22
0.64
0.49
7.59
2278.14
14
70
1.17
2.2
0.715
0.22
0.64
0.49
7.59
2278.14
15
75
1.25
2.2
0.715
0.22
0.64
0.49
7.59
2278.14
16
80
1.33
2.0
0.650
0.22
0.59
0.43
6.59
1977.65
17
85
1.42
2.6
0.846
0.22
0.76
0.62
9.60
2879.11
18
90
1.50
2.7
0.878
0.22
0.79
0.66
10.10
3029.35
19
95
1.58
2.4
0.780
0.22
0.70
0.56
8.60
2578.62
20
100
1.67
2.7
0.878
0.22
0.79
0.66
10.10
3029.35
21
105
1.75
3.3
1.073
0.22
0.97
0.85
13.10
3930.81
22
110
1.83
3.1
1.008
0.22
0.91
0.79
12.10
3630.32
23
115
1.92
2.9
0.943
0.22
0.85
0.72
11.10
3329.84
24
120
2.00
3.0
0.976
0.22
0.88
0.75
11.60
3480.08
25
125
2.08
3.1
1.008
0.22
0.91
0.79
12.10
3630.32
26
130
2.17
4.2
1.366
0.22
1.23
1.14
17.61
5282.99
27
135
2.25
5.0
1.626
0.22
1.46
1.40
21.62
6484.93
28
140
2.33
3.5
1.138
0.22
1.02
0.92
14.10
4231.29
29
145
2.42
6.8
2.211
0.22
1.99
1.99
30.63
9189.29
30
150
2.50
7.3
2.374
0.22
2.14
2.15
33.14
9940.50
31
155
2.58
8.2
2.667
0.22
2.40
2.44
37.64
11292.68
32
160
2.67
5.9
1.919
0.22
1.73
1.70
26.12
7837.11
33
165
2.75
2.0
0.650
0.22
0.59
0.43
6.59
1977.65
34
170
2.83
1.8
0.585
0.22
0.53
0.36
5.59
1677.17
35
175
2.92
1.8
0.585
0.22
0.53
0.36
5.59
1677.17
36
180
3.00
0.6
1 0.195
0.22
0.18
0.02
0.30
90.15
EFFECTIVE RAIN & FLOOD VOLUMES SUMMARY
EFFECTIVE RAIN (in)
2.05
FLOOD VOLUME (acft)
2.63
FLOOD VOLUME (cuft)
114425.41
REQUIRED STORAGE (acft)
2.61
REQUIRED STORAGE (cult)
113479.30
PEAK FLOW RATE (cfs)
37.64
Plate E -2.2
Page 6 of 18
RCFCD SYNTHETIC UNIT HYDROGRAPH METHOD
100 YEAR - 6 HOUR STORM EVENT
PROJECT: LA QUINTA RESORT SPECIFIC PLAN AMENC
CONCENTRATION POINT: 1
BY: JAMES R. BAZ DATE: 7/1312009
EFFECTIVE
RAIN CALCULATION FORM
DRAINAGE AREA -ACRES 15.40
UNIT TIME - MINUTES 5
LAG TIME - MINUTES 3.17
UNIT TIME - PERCENT OF LAG 157.8
TOTAL ADJUSTED STORM RAIN - INCHES 3.28
CONSTANT LOSS RATE -in/hr 0.222
LOW LOSS RATE - PERCENT 90%
TOTAL PERCOLATION RATE (cfs) 0.00 cfs
Unit Time
Period
Time
Minutes Hours
Pattern
Percent
Plate E -5.9
Storm
Rain
in/hr
Loss Rate
in/hr
Max Low
Effective
Rain
in/hr
Flood
Hydrograph
Flow
cfs
Required
Storage
cf, .
1
5
0.08
0.5
0.197
0.22
0.18
0.02
0.30
90.92
2
10
0.17
0.6
0.236
0.22
0.21
0.01
0.21
63.87 -
3
15
0.25
0.6
0.236
0.22
0.21
0.01
0.21
63.87
4 " .
20
0.33
0.6
0.236
0.22
0.21
0.01
0.21
63.87
5
25
0.42
0.6
0.236
0.22
0.21
0.01
0.21
63.87
6
30
0.50
0.7
0.276
0.22
0.25
0.05
0.82
245.71
7
35
0.58
0.7
0.276
0.22
0.25 -
0.05
0.82
245.71
8
40
0.67
0.7
0.276
0.22
0.25
0.05
0.82
245.71
9
45
0.75
0.7
0.276
0.22
0.25
0.05
0.82
•245.71
10
50
0.83
0.7
0.276
0.22
0.25
0.05
0.82
245.71
11
55
0.92
0.7
0.276
0.22
0.25
0.05
0.82
245.71
12
60
1.00
0.8
0.315
0.22
0.28
0.09
1.43
427.55
13
65
1.08
0.8
0.315
0.22
0.28
0.09
1.43
427.55
14
70
1.17.,
0.8
0.315
0.22
0.28
0.09
1.43
427.55
15
75
1.25
0.8
0.315
0.22
0.28
0.09
1.43
427.55
16
80
1.33
0.8
0.315
0.22
0.28
0.09
1.43
427.55
17
85
1.42
0.8
0.315.
0.22
0.28
0.09
1.43
427.55
18
90
1.50
0.8
0.315
0.22
0.28
0.09
1.43
427.55
19
95
1.58
0.8
0.315
0.22
0.28
0.09
1.43
427.55
20
100.
1.67
0.8
0.315
0.22
.0.28
0.09
1.43
427.55
21
105
1.75
0.8
0.315
0.22
0.28
0.09
1.43
427.55
22
110
1.83
0.8
0.315
0.22
0.28
0.09
1.43
427.55
23 _
115
1.92
0.8
0.315
0.22
0.28
0.09
1.43
427.55
24
120
2.00
0.9
0.354
0.22
0.32
0.13
2.03
609.39
25
- 125
2.08
0.8
0.315
0.22
0.28
0.09
1.43
427.55
26
130
2.17
0.9
0.354
0.22
0.32
0.13
2.03
609.39
27
135
2.25
0.9
0.354
0.22
0.32
0.13
2.03
609.39
28
140
2.33
0.9
0.354
0.22
0.32
0.13
2.03.
609.39
29
145
.2.42
0.9
0.354
0.22
0.32
0.13
2.03
609.39
30
150
2.50 _
0.9
0.354
0.22
0.32
0.13
2.03
609.39
31
155
2.58
0.9
0.354
0.22
0.32
0.13
2.03
609.39
32
160
2.67
0.9
0.354
0.22
0.32
0:13
2.03
609.39 .
33
165
2.75
1.0
0.394
0.22
0.35
0.17
2.64
791.24
34
170
2.83
1.0
0.394
0.22
0.35
0.17
2.64
791.24
35
175
2.92
1.0
0.394
0.22
0.35
0.17
2.64
791.24
36
180
3.00
1.0
0.394
0.22
0.35
0.17
2.64
791.24 _
37
185
3.08
1.0
0.394
0.22
0.35
0.17
2.64
791.24 .
38
190
3.17
1.1
0.433
0.22
0.39
0.21
3.24
973.08
39
195
3.25
1.1
0.433
0.22
0.39
0.21
3.24
973.08
40
200
3.33
1.1
0.433
0.22
0.39
0.21
3.24
973.08
41
205
3.42
1.2
0.472
0.22
0.43
0.25
3.85
1154.92
42
210
3.50
1.3
0.512
0.22
0.46
0.29
4.46
1336.77
43
215
.3.58
1.4
0.551.
0.22
0.50
0.33
5.06
1518.61
44
220
3.67
1.4
0.551
0.22
0.50
0.33
5.06
1518.61
45
225
3.75
1.5
0.590
0.22
0.53
0.37
5.67
1700.45
46
230
3.83
1.5
0.590
0.22
0.53
0.37
5.67
1700.45
.47
235
3.92
1.6
0.630
0.22
0.57
0.41
6.27
1882.30
48
240
4.00
1.6
0.630
0.22
0.57
0.41
6.27
1882.30
49
245
4.08
1.7
0.669
0.22
0.60
0.45
6.88
2064.14
50
250
4.17
1.8
0.708
0.22
0.64
0.49
7.49
2245.98
51
255.
4.25
1.9
0.748
0.22
0.67
0.53
8.09
2427.83
52
260
4.33
2.0
0.787
0.22
0.71
0.56
8.70
2609.67
53
265
4.42
2.1
0.827
0.22
0.74
0.60
9.31
2791.51
54
270
4.50
2.1
0:827
0.22
0.74
0.60
9.31
2791.51
55
275
4.58
2.2
0.866
0.22
0.78
0.64
9.91
2973.36
56
280
4.67
2.3
0.905
0.22
0.81
0.68
10.52
3155.20
Plate E -2.2
Page 7 of 18
r
RCFCD SYNTHETIC UNIT HYDROGRAPH METHOD
100 YEAR - 6 HOUR STORM EVENT
PROJECT: LA QUINTA RESORT SPECIFIC PLAN AMEN[
CONCENTRATION POINT: 1
P.
BY: JAMES R. BAZ DATE: 7/13/2009
EFFECTIVE RAIN (in)
1.98
EFFECTIVE
RAIN CALCULATION FORM
FLOOD VOLUME (cult)
110452.38
REQUIRED STORAGE (acft)
DRAINAGE AREA -ACRES
UNIT TIME - MINUTES
LAG TIME - MINUTES
UNIT TIME - PERCENT OF LAG
TOTAL ADJUSTED STORM RAIN - INCHES
CONSTANT LOSS RATE -in/hr
LOW LOSS RATE - PERCENT
15.40
5
3.17
157.8
3.28
0.222
90%
TOTAL PERCOLATION RATE (cfs)
PEAK FLOW RATE (cfs)
0.00 cfs
Unit Time
Period
Time ,
Minutes Hours
Pattern
Percent
Plate E -5.9
Storm
Rain
in/hr
Loss Rate
in/hr
Max
Low
Effective
Rain
in/hr
Flood
Hydrograph
Flow
cfs,
Required
Storage
cf
57.
285
4.75
2.4
0.945
0.22
0.85
0.72
11.12
3337.04
58
290
4.83
2.4
0.945
0.22
0.85
0.72
11.12
3337.04
59
295
4.92
2.5
0.984
0.22
0.89
1 0.76
11.73
3518.89
60
300
5.00
2.6
1.023
0.22
0.92
0.80
12.34
3700.73
61
305
5.08
3.1
1.220
0.22
1.10
1.00
15.37
4609.95
62
310
5.17
3.6
1.417
0.22
1.28
1.19
18.40
5519.16
63 _
315
5.25,
3.9.
1.535
0.22
1.38
1.31
20.22
6064.69
64
320
5.33,
4.2
1.653
0.22
1.49
1.43
22.03
6610.22
65,
325
5.42.
4.7
1.850
0.22
1.66
1.63
25.06
7519.44
66
330
5.50
5.6
2.204
0.22
1.98.
1.98
30:52
9156.03
67
335
5.58
1.9
0.748
0.22
0.67
0.53
8.09
2427.83
68
340
5.67
•0.9
0.354
0.22
0.32
0.13
2.03
609.39
69
345
5.75
0.6
0.236
.0.22
0.21
0.01
0.21
63.87
70 _
350
5.83
0.5
0.197
0.22
0.18
0.02
0.30
90.92
71
355
5.92
0.3
0.118
0.22
0.11
0.01
0.18
54.55
72 _
360
6.00.
0.2
0.079
0.22
0.07
0.01
0.12
36.37
EFFECTIVE RAIN & FLOOD VOLUMES SUMMARY
EFFECTIVE RAIN (in)
1.98
FLOOD VOLUME (acft)
2.54
FLOOD VOLUME (cult)
110452.38
REQUIRED STORAGE (acft)
2.51
REQUIRED STORAGE (cult)
109539.12
PEAK FLOW RATE (cfs)
30.52
Plate E -2.2
Page 8 of 18
j
RCFCD SYNTHETIC UNIT HYDROGRAPH METHOD
100 YEAR - 24 HOUR STORM EVENT
PROJECT: LA QUINTA RESORT SPECIFIC PLAN AMEND
CONCENTRATION POINT: 1 -
BY: JAMES R. BAZ DATE: .7/1312009
EFFECTIVE RAIN CALCULATION FORM
DRAINAGE AREA -ACRES 15.400
UNIT TIME - MINUTES 15
LAG TIME - MINUTES 3.17
UNIT TIME - PERCENT OF LAG 473.5
TOTAL ADJUSTED STORM RAIN - INCHES 4.38
CONSTANT LOSS RATE - in/hr n/a
VARIABLE LOSS RATE (AVG) in/hr 0.2223
MINIMUM LOSS RATE (for var. loss) - in/hr 0.111
LOW LOSS RATE - DECIMAL 0.90
C 0.00206
PERCOLATION RATE cfs 0.00
Unit Time
Period
Time
Minutes Hours
Pattern
Percent
Plate E -5.9
Storm
Rain
in/hr
Loss Rate
' in/hr
Max Low
Effective
Rain
in/hr
Flood
Hydrograph
Flow
cfs
Required
Storage
cf
1
15
0.25
0.2
0.035
0.393 -
0.032
0.004
0.05
48.57
2
30
0.50
0.3
0.053.
0.388
0.047
0.005
0.08
72.85
3
45
0.75
0.3
0.053
0.384
0.047
0.005
0.08
72.85
4
60
1.00
0.4 1
0.070
0.379
0.063 1
0.007
0.11
97.13
5
75
1.25
0.3
0.053
0.375
0.047
0.005
0.08
72.85
6
90
1.50
0.3
0.053
0.370
0.047
0.005
0.08
72.85
7
105
1.75
0.3
0.053
0.366
0.047
0.005
0.08
72.85
8
120
2.00
0.4
0.070
0.361
0.063
0.007
0.11
97.13
9
135
2.25
0.4
0.070
0.357
0.063
0.007
0.11
97.13
10
150,
2.50
0.4
0.070
0.353
0.063
0.007
0.11
97.13
11
165
2.75
0.5
0.088
0.348
0.079
0.009
0.13
121.41
12
180
3.00
0.5
0.088
0.344
0.079
0.009
0.13
121.41
13
195
3.25
0.5
0.088
0.340
0.079.
0.009
0.13
121.41
14
210
3.50
0.5
0.088
0.336
0.079
0.009
0.13
121.41
15
225
.3.75
0.5
0.088
0.331
0.079
0.009
0.13
121.41
16
240
4.00
0.6
0.105
0.327
0.095
0.011
0.16
145.70
17
255
4.25
0.6
0.105
0.323
0.095
0.011
0.16
145.70
18
270
4.50
0.7
0.123
0.319
0.110
0.012
0.19
169.98
19
285
4.75
1 0.7
0.123
0.315
0.110
0.012
0.19
169.98
20
.300
5.00
0.8
0.140
0.311
0.126
0.014
0.22
194.26
21
315
5.25
0.6
0.105
0.307
0.095
0.011
0.16
145.70
22
330
5.50
0.7
0.123
0.303
0.110
0.012
0.19
169.98
23
345
5.75
0.8
0.140
0.299
0.126
0.014
0.22
194.26
24
360
6.00
0.8
1 0.140
0.295
0.126
0.014
0.22
194.26
25
375
6.25
0.9
0.158
0.291
0.142
0.016
0.24
218.54
26
390
6.50
0.9
0.158
0.287
0.142
0.016
0.24
218.54
27
405
6.75
1.0
0.175
0.283
0.158
0.018
0.27
242.83
28
420
7.00
1.0.
0.175
0.279
0.158
0.018
0.27
242.83
29
435
7.25
1.0
0.175
0.276
0.158
0.018
0.27
242.83
30
450
7.50
1.1
0.193
0.272
0.173
0.019
0.30
267.11
31
465
7.75
1.2
0.210
1 0.268
0.189
0.021
0.32
291.39
32
480
8.00
1.3
0.228
0.264
0.205
0.023
0.35
315.68
33
495
8.25
1.5
0.263
0.261
0.237
0.002
0.03
29.30
34
510
8.50
1.5
0.263
0.257
0.237
0.006
0.09
79.66
35
525
8.75
1.6
0.280
0.253
1 0.252
0.027
0.41
372.41
36
540
9.00
1.7 ,
0.298
0.250
0.048
0.74
664.72
37
555
9.25
1.9
0.333
0.246
0.087
1.33
1199.41
38
570
9.50
2.0
0.350
0.243
0.108
1.66
1490.81
39
585
9.75
2.1
0.368
0.239
tO.268
0.129
1.98
1781.77
40
600
10.00
2.2
0.385
0.236 _
0.150
2.30
2072.26
41
615
10.25
1.5
0.263
0.233
0.030
0.47
419.67
42
630
10.50
1.5
0.263
0.229
0.034
0.52
466.41
43
645
10.75
2.0
0.350
0.226
0.315
0.125
1.92
1726.82
44
660
11.00
2.0
0.350
0.223
0.315
0.128
1.97
1772.62
45
675
11.25
1.9
0.333
0.219
0.300
0.114
1.75
1575.11
46
690
11.50
1.9.
0.333
0.216
0.300
0.117
1.80
1619.95
47 •
705
11.75
1.7
0.298
0.213
0.268
0.085
1.31
1178.65
48
720
12.00
1.8
0.315
0.210
0.284
0.106
1.63
1465.34
49.
735
12.25
2.5
0.438
1 0.207
0.394
0.231
3.56
3208.50
50
750
12.50
2.6
0.456
0.203
0.410
0.252
3.88
3494.19
51
765
12.75
2.8
0.491
0.200
0.442
0.290
4.47
4022.21
.52
780
13.00
2.9
0.508
0.197
0.457
0.311
4.79
4306.89
53
795
13.25
3.4
0.596
0.194
0.536
0.401
6.18
5562.37
54
810
13.50
3.4
0.596
0.191
0.536
0.404
6.23
5603.19
55
825
13.75.
2.3
0.403
0.189
0.363
0.214
3.30
2972.39
56
840
14.00
2.3
0.403
0.186
0.363
0.217
1 3.35
3012.16
57
855
14.25
2.7
0.473
0.183
0.426
0.290
4.47
4022.70
58
870
14.50
2.6
0.456
0.180
0.410
0.276
4.24
3818.56
59
885
14.75
2.6
0.456
0.177
0.410
0.278
4.29
3856.70
60
900
15.00
2.5
0.438
0.175
0.394
0.263
4.06
3651.45
61
915
15.25
2.4
0.420
0.172
0.378
0.249
3.83
3445.65
62
930
15.50
2.3
0.403
0.169
0.363
0.234
3.60
3239.27
63
945
15.75
1.9
0.333
0.167
0.300
0.166
2.56
2303.84
64
960
16.00
1.9
0.333
0.1164
0 .300
0.169
2.60
2339.13
65
975
16.25
0.4
0.070
0.162
0.063
0.007
0.11
97.13
66
990
16.50
0.4.
0.070
0.159
0.063
0.007
0.11
97.13
67
1005
16.75
0.3
0.053
0.157
0.047
0.005
0.08
72.85
}
DENT NO. 6, F
t
i
r
Plate E -2.2
Page 9 of 18
RCFCD SYNTHETIC UNIT HYDROGRAPH METHOD
100 YEAR - 24 HOUR STORM EVENT
PROJECT: LA QUINTA RESORT SPECIFIC PLAN AMEN[
CONCENTRATION POINT: 1
BY: JAMES R. BAZ DATE: 711312009
EFFECTIVE
RAIN CALCULATION
FORM
DRAINAGE AREA -ACRES 15.400
UNIT TIME- MINUTES 15
LAG TIME - MINUTES 3.17
UNIT TIME - PERCENT OF LAG 473.5
TOTAL ADJUSTED STORM RAIN- INCHES 4.38
CONSTANT LOSS RATE - in/hr n/a
VARIABLE LOSS RATE (AVG) in/hr 0.2223
MINIMUM LOSS RATE (far var. loss) - in/hr 0.111
LOW LOSS RATE - DECIMAL 0.90
C 0.00206
PERCOLATION RATE cfs 0.00
Unit Time
Period
Time
Minutes Hours
Pattern
Percent
Plate E -5.9
Storm
Rain
in/hr
Loss Rate
in/hr
Max Low
Effective
Rain
in/hr
Flood
Hydrograph
Flow
cis
Required
Storage
cf
68
1020
17.00
0.3
0.053
0.154
0.047
0.005
0.08
72.85
69
1035
17.25
0.5
0.088
0.152
0.079
0.009.
0.13
121.41
70
1050
17.50
0.5
0.088
0.150
0.079
0.009
0.13
121.41
71
1 1065
17.75
0.5
0.088
0.148
0.079
0.009
0.13
121.41
72
1080
18.00
.0.4
0.070
0.145
0.063
0.007
0.11
97.13
73
1095
18.25
0.4
0.070
0.143
0.063
0.007
0.11
97.13
74
1110 _
18.50
0.4
0.070
0.141
0.063
0.007
0.11
97.13
75
1125
18.75
0.3
0.053 '
0.139
0.047
0.005
0.08
72.85
76
1140
19.00
0.2
0.035
0.137
0.032
0.004
0.05
48.57
77_
1155.
19.25
0.3
0.053
0.135
0.047
0.005.
0.08
72.85
78
1170
19.50
0.4
0.070.
0.133
0.063
0.007
0.11
1 97.13
79,
1185.
19.75
.0.3
0.053
0.131
0.047
0.005
0.08
72.85
80
1200
20.00
0.2
0.035
0.130
0.032
0.004
0.05
48.57
81
1215
20.25
0.3
0.053
0.128
0.047
0.005
0.08
72.85
82
1230-
20.50
0.3
0.053
0.126.
0.047
0.005
0.08
72.85
83
1245
20.75
0.3
0.053
0.125
0.047
0.005
0.08
72.85
84
1260._
21.00
0.2
0.035
0.123
0.032
0.004
0.05
48.57
85
1275
21.25
0.3
0.053
0.122
0.047
0.005
0.08
72.85
86
.1290
21.50
0.2
0.035
0.120
0.032
0.004
0.05
48.57
87
1305
21.75
0.3
0.053
0.119
0.047
0.005.
0.08
72.85
88
1320
22.00
0.2.
0.035
0.118
0.032
0.004
0.05
48.57
89
1335
22.25
0.3
0.053
0.117
0.047
0.005
0.08
72.85
90
1350
22.50
0.2
0.035
0.116
0.032
0.004
0.05
48.57
91
1365
22.75
0.2
0.035
0.115
0.032
0.004
0.05
48.57
92
1380
23.00
0.2
0.035
0.114
0.032,
0.004
0.05
48.57
93
1395
23.25
0.2
0.035
0.113
0.032
0.004
0.05
48.57
94
1410
23.50
0.2
0.035
0.112
0.032
0.004
0.05
48.57
95
1425
23.75
0.2
0.035
0.112
0.032
0:004
0.05
48.57
96
1440
24.00
0.2
0.035
0.111 ,
0.032
0.004
0.05
48.57
MENT NO. 6, F
Plate E -2.2
Page 10 of 18
1
t
EFFECTIVE RAIN & FLOOD VOLUMES SUMMARY
'
EFFECTIVE RAIN (in)
1.52
FLOOD VOLUME (acft)
1.95
FLOOD VOLUME (tuft)
84784.22
REQUIRED STORAGE (acft)
1.93
'
REQUIRED STORAGE (cult)
84083.20
PEAK FLOW cfs
6.23
MENT NO. 6, F
Plate E -2.2
Page 10 of 18
1
t
1
TKC JOB # 2017110600
100 YEAR -3 HOUR STORM EVENT
TIME
UNIT (min)
PERIOD
FLOW
IN
cfs
VOLUME
IN
cult
TOTAL IN
BASIN
cult
PERC
OUT
cult
TOTAL IN
BASIN
cult
BASIN
DEPTH .
ft
BALANCE IN
BASIN
cult acre -ft
1
5
3.09
926
926
0
926
926
0.02
2
10
3.09
926
1,852
0
1,852
1,852
0.04
3
15
2.08
625
2,477
0
2,477
-
2,477
0.06
4
.20
4.09
1,226
3,704
0
3,704
3,704
0.09
5
25
4.09
1,226
4,930
0
4,930
4,930
0.11
6 r
30
5.59
1,677
6,607
0
6,607
-
6,607
0.15
7
35
4.09
1,226
7,834
0
7,834
-
7,834
0.18
8
40
5.59
1,677
9,511
0
9,511
-
9,511
0.22
9
45
5.59
1,677
11,188
0
11,188
-
11,188
0.26
10
50
4.09
1,226
12,415
0
12,415
-
12,415
0.29
11
55,
4.59
1,377
13,791
0
13,791
-
13,791
0.32
12
60
5.59
1,677
15,469
0
15,469
-
15,469
0.36
13
65
7.59
2,278
17,747
0
17,747
-
17,747
0.41
14
70
7.59.
2,278
20,025
0
20,025
-
20,025
0.46
15
75
7.59
2,278
22,303
0
22,303
-
22,303
0.51
16
80
6.59
1,978
24,281
0
24,281
-
24,281
0.56
17
85_
9.60
2,879
27,160
0
27,160
-
27,160
0.62
18
90
10.10
3,029
30,189
0
30,189
-
30,189
0.69
19
95
8.60
2,579
32,768
0
32,768
-
32,768
0.75
20.
100
10.10
3,029
35,797
0
35,797
-
35,797
0.82
21
105
13.10
3,931
39,728
0,
39,728
-
39,728
0.91
22
110
12.10
3,630
43,358
0
43,358
-
43,358
1.00
23
115
11.10
3,330
46,688
0
46,688
-
46,688
1.07
24
120
11.60
3,480
50,168
0
50,168
-
50,168
1.15
25
125
12.10
, 3,630
53,798
0
53,798
-
53,798
1.24
26
130
17:61
5,283
59,081
0
59,081
-
59,081
1.36
27
135
21.62
6,485
65,566
0
65,566
-
65,566
1.51
28
140
14.10
4,231
69,798
0
69,798
-
69,798
1.60
29
145
30.63
9,189
78,987
0
78,987
-
78,987
1.81
30
150
33.14
.9,941
88,927
0
88,927
-
88,927
2.04
31
155
37.64
11,293
100,220
0
100,220
-
100,220
2.30
32
160
26.12
7,837
108,057
0
108,057
-
108,057
2.48
33
165
6.59
1,978
110,035
01
110,035
-
110,035
2.53
34
170
5.59
1,677
111,712
0
111,712
-
111,712
2.56
35
175
5.59
1,677
113,389
0
113,389
-
113,389
2.60
36
180
0.30
90
113,479
0
113,479
-
113,479
2.61
FA
Basin Depth Analysis
Page 14 of 18
i 1
TKC JOB # 2017110600
100 YEAR - 6 HOUR STORM EVENT
TIME
UNIT (min)
PERIOD
FLOW
IN
cfs
VOLUME
IN
cult
TOTAL IN
BASIN
cult
PERC
OUT
cult
TOTAL IN
BASIN
cult
BASIN
DEPTH
ft
BALANCE IN
BASIN
cult acre -ft
1
5
0.30
91
91
0
91
91
0.00
2
10
0.21
64
155
0
155
+
155
0.00
3
15
0.21
64
2191
0
219
219
0.01
4
20
0.21
64
283
0
283
283
0.01
5
25
0.21
64
346
0
346
346
0.01
6
30
0.82
246
592
0
592
-
592
0.01
7
35
0.82
246
838
0
838
838
0.02
8
40
0.82
246
1,084
0
1,084
1,084
0.02
9
45
0.82
246
1,329
0
1,329
1,329
0.03
10
50
0.82
246
1,575
0
1,575
1,575
0.04
11
55
0.82
246
1,821
0
1,821
1,821
0.04
12
60
1.43
428
2,248
0
2,248
2,248
0.05
13
65
1.43
428
2,676
0
2,676
2,676
0.06
14
70
1.43
428
3,103
0
3,103
3,103
0.07
15
75
1.43
428
3,531
0
3,531
3,531
0.08
16
80
1.43
428
3,958
0
3,958
3,958
0.09
17
85
1.43
428
4,386
0
4,386
4,386
0.10
18
90
1.43
428
4,813
0
4,813
4,813
0.11
19
95
1.43
428
5,241
0
5,241
5,241
0.12
20
100
1.43
428
5,669
0
5,669
-
5,669
0.13
21
105
1.43
428
6,096
0
6,096
6,096
0.14
22
110
1.43
428
6,524
0
6,524
6,524
0.15
23
115
1.43
428
6,951
0
6,951
6,951
0.16
24
120
2.03
609
7,561
0
7,561
7,561
0.17
25
125
1.43
428
7,988
0
7,988
7,988
0.18
26
130
2.03
609
8,598
0
8,598
8,598
0.20
27
135.
2.03
609
9,207
0
9,207
9,207
0.21
28
140
2.03
609
9,816
01
9,816
9,816
0.23
29
145
2.03
609
10,426
0
10,426
10,426
0.24
30
150
2.03
609
11,035
0
11,035
11,035
0.25
31
155
2.03
609
11,645
0
11,645
-
11,645
0.27
32
160
2.03
609
12,254
0
12,254
-
12,254
0.28
33
165
2.64
791
13,045
0
13,045
-
13,045
0.30
34
170
2.64
791
13,836
0
13,836
-
13,836
0.32
35
175
2.64
791
14,628
0
14,628
-
14,628
0.34
36
180
2.64
791
15,419
0
15,419
-
15,419
0.35
37
185
2.64
791
16,210
0
16,210
-
16,210
0.37
38
190
3.24
973
17,183
0
17,183
-
17,183
0.39
39
195
3.24
973
18,156
0
18,156
-
18,156
0.42
40
200
3.24
973
19,129
0
19,129
-
19,129
0.44
41
205
3.85
1,155
20,284
0
20,284
-
20,284
0.47
42
210
4.46
1,337
21,621
0
21,621
-
21,621
0.50
43
215
5.06
1,519
23,140
0
23,140
-
23,140
0.53
44
220
5.06
1,519
24,658
0
24,658
-
24,658
0.57
45
225
5.67
1,700
26,359
0
26,359
-
26,359
0.61
46
230
5.67
1,700
28,059
0
28,059
-
28,059
0.64
47
235
6.27
1,882
29,942
0
29,942
-
29,942
0.69
48
240
6.27
1,882
31,824
0
31,824
-
31,824
0.73
49
245
6.88
2,064
33,888
0
33,888
-
33,888
0.78
50
250
7.49
2,246
36,134
0
36,134
-
36,134
0.83
51
255
8.09
2,428
38,562
0
38,562
-
38,562
0.89
52
260
8.70
2,610
41,171
0
41,171
-
41,171
0.95
53
265
9.31
2,792
43,963
0
43,963
-
43,963
1.01
54
270
9.311
2,792
1 46,754
0
46,754
1
46,754F
1.07
55
275
1 9.911
2,973
1 49,728
0
49,728
1 -
49,728
1.14
Basin Depth Analysis
Page 15 of 18
i
G,
1
TKC JOB # 2017110600
100 YEAR - 6 HOUR STORM EVENT
TIME
UNIT (min)
PERIOD
FLOW
IN
cfs
VOLUME
IN
cult
TOTAL IN
BASIN
cult
PERC
OUT
cuff
TOTAL IN
BASIN
cult
BASIN
DEPTH
ft
BALANCE IN
BASIN
cult acre -ft
56
280
10.52
3,155
52,883
0
52,883
52,883
1.21
57
285
11.12
3,337
56,220
0
56,220
56,220
1.29
58
290
11.12
3,337
59,557
0
59,557
59,557
1.37
59
295
11.73
3,519
63,076
0
63,076
63,076
1.45
60
300
12.34
3,701
66,777
0
66,777
66,777
1.53
61
305
15.37
4,610
71,387
0
71,387
71,387
1.64
62
310
18.40
5,519
76,906
0
76,906
76,906
1.77
63
315
20.22
6,065
82,971
0
82,971
82,971
1.90
64
320
22.03
6,610
89,581
0
89,581
89,581
2.06
65
325
25.06
7,519
97,100
01
97,100
97,100
2.23
66
330
30.52
9,156
106,256
0
106,256
106,256
2.44
67
335
8.09
2,428
108,684
0
108,684
108,684
2.50
68
340
2.03
609
109,293
0
109,293
-
109,293
2.51
69.
345
0.21
64
109,357
0
109,357
109,357
2.51
70
.350
0.30
91.
109,448
0
109,448
109,448
2.51
71
355
0.18
55
109,503
0
109,503
109,503
2.51
72
360
0.121
36
1 109,539
01
109,539
109,539
2.51
Basin Depth Analysis
Page 16 of 18
i
Basin Depth Analysis
Page 16 of 18
1
TKC JOB # 2017110600
100 YEAR - 24 HOUR STORM EVENT
TIME
UNIT (min)
PERIOD
FLOW
IN
cfs
VOLUME
IN
cult
TOTAL IN
BASIN
cult
PERC
OUT
cult
TOTAL IN
BASIN
cult
BASIN
DEPTH
ft
BALANCE IN
BASIN
cult acre -ft
1
15
0.05
49
49
0
49
49
0.00
2
30
0.08
73
121
0
121
121
0.00
3
45
0.08
73
194
0
194
194
0.00
4
60
0.11
97
291
0
291
291
0.01
5
75
0.08
73
364
0
364
364
0.01
6
90
0.08
73
437
0
437
437
0.01
7
105
0.08
73
510
0
510
510
0.01
8
120
0.11
97
607
0
607
607
0.01
9
135
0.11
97
704
0
704
704
0.02
10
150
0.11
97
801
0
801
801
0.02
11
165
0.13
121
923
0
923
923
0.02
12
180
0.13
121
1,044
0
1,044
1,044
0.02
13
195
0.13
121
1,166
0
1,166
1,166
0.03
14
210
0.13
121
1,287
0
1,287
1,287
0.03
15
225
0.13
121
1,408
0
1,408
1,408
0.03
16
240
0.16
146
1,554
0
1,554
1,554
0.04
17
255
0.16
146
1,700
0
1,700
1,700
0.04
18
270
0.19
170
1,870
0
1,870
1,870
0.04
19
285
0.19
170
2,040
0
2,040
2,040
0.05
20
300
0.22
194
2,234
0
2,234
2,234
0.05
21
• 315
0.16
146
2,380
0
2,380
2,380
0.05
22
330
0.19
170
2,550
0
2,550
2,550
0.06
23
345
0.22
194
2,744
0
2,744
2,744
0.06
24
360
0.22
194
2,938
0
2,938
2,938
0.07
25
375
0.24
219
3,157
0
3,157
3,157
0.07
26
390
0.24
219
3,375
0
3,375
3,375
0.08
27
405
0.27
243
3,618
0
3,618
3,618
0.08
28
420
0.27
243
3,861
0
3,861
3,861
0.09
29
435
0.27
243
4,104
0
4,104
4,104
0.09
30
450
0.30
267
4,371
0
4,371
4,371
0.10
31
465
0.32
291
4,662
0
4,662
4,662
0.11
32
480
0.35
316
4,978
0
4,978
4,978
0.11
33
495
0.03
29
5,007
0
5,007
5,007
0.11
34
510
0.09
80
5,087
0
5,087
5,087
0.12
35
525
0.41
372
5,459
0
5,459
5,459
0.13
36
540
0.74
665
6,124
0
6,124
6,124
0.14
37
555
1.33
1,199
7,323
0
7,323
7,323
0.17
38
570
1.66
1,491
8,814
0
8,814
-
8,614
0.20
39
585
1.98
1,782
10,596
0
10,596
10,596
0.24
40
600
2.30
2,072
12,668
0
12,668
12,668
0.29
41
615
0.47
420
13,088
0
13,088
13,088
0.30
42
630
0.52
466
13,554
0
13,554
13,554
0.31
43
645
1.92
1,727
15,281
0
15,281
15,281
0.35
44
660
1.97
1,773
17,054
0
17,054
17,054
0.39
45
675
1.75
1,575
18,629
0
18,629
18,629
0.43
46
690
1.80
1,620
20,249
0
20,249
20,249
0.46
47
705
1.31
1,179
21,428
0
21,428
21,428
0.49
48.
720
1.63
1,465
22,893
0
22,893
22,893
0.53
49
735
3.56
3,208
26,101
0
26,101
26,101
0.60
50
750
3.88
3,494
29,596
0
29,596
29,596
0.68
51
765
4.47
4,022
33,618
0
33,618
33,618
0.77
52
780
4.79
4,307
37,925
0
37,925
37,925
0.87
53
795
6.18
5,562
43,487
0
43,487
43,487
1.00
54
810
6.23
5,603
49,090
0
49,090
49,090
1.13
55
825
3.30
2,972
52,063
0
52,063
52,063
1.20
56
840
3.35
3,0121
55,075
0
55,075
55,075
1.26
57
855
4.47
4,023
1 59,097
0
59,097
59,097
1.36
58
870
4.241
3,819
1 62,916
1 01
62,916
62,916
1.44
Basin Depth Analysis
Page 17 of 18
I
TKC JOB # 2017110600
iM VFGR - 9d HCII IR RTr)RM FVFNT
TIME
UNIT (min)
PERIOD
FLOW
IN
cfs
VOLUME
IN
cult
TOTAL IN
BASIN
cult
PERC
OUT
cult
TOTAL IN
BASIN
cult
BASIN
DEPTH
ft
BALANCE IN
BASIN
cult acre -ft
59
885
4.29
3,857
66,773
0
66,773
66,773
1.53
60
900
4.06
3,651
70,424
0
70,424
70,424
1.62
61
915
3.83
3,446
73,870
0
73,870
73,870
1.70
62
930
3.60
3,239
77,109
0
77,109
77,109
1.77
63
945
2.56
2,304
79,413
0
79,413
79,413
1.82
64
960
2.60
2,339
81,752
0
81,752
81,752
1.88
65
975
0.11
97
81,849
0
81,849
81,849
1.88
66
990
0.11
97
81,946
0
81,946
81,946
1.88
67
1005
0.08
73
82,019
0
82,019
82,019
1.88
68
1020
0.08
73
82,092
0
82,092
82,092
1.88
69
1035.
0.13
121
82,213
0
82,213
82,213
1.89
70
1050
0.13
121
82,335
0
82,335
82,335
1.89
71
1065
0.13
121
82,456
0
82,456
82,456
1.89
72
1080
0.11
97
82,553
0
82,553
82,553
1.90
73
1095
0.11
97
82,651
0
82,651
82,651
1.90
74
1110
0.11
97
82,748
0
82,748
82,748
1.90
75
1125
0.08
73
82,820
0
82,820
82,820
1.90
76
1140
0.05
49
82,869
0
82,869
82,869
1.90
77
1155
0.08.
73
82,942
0
82,942
82,942
1.90
78
1170
0.11
97
83,039
0
83,039
83,039
1.91
79
1.185
0.08
73
83,112
0
83,112
83,112
1.91
80
1200
0.05
49
83,160
0
83,160
83,160
1.91
81
1215
0.08
73
83,233
0
83,233
83,233
1.91
82
1230
0.08
73
83,306
0
83,306
83,306
1.91
83
1245
0.08
73
83,379
0
83,379
83,379
1.91
84
1260
0.05
49
83,428
0
83,428
83,428
1.92
85
1275
0.08
73
83,500
0
83,500
83,500
1.92
86
1290
0.05
49
83,549
0
83,549
83,549
1.92
,87
1305
0.08
73
83,622
0
83,622
83,622
1.92
88
1320
0.05
49
83,670
0
83,670
83,670
1.92
89
1335
0.08
73
83,743
0
83,743
83,743
1.92
90
1350
0.05
49
.83,792
0
83,792
83,792
1.92
91
1365
0.05
49
83,840
0
83,840
83,840
1.92
92
1380
0.05
49
83,889
0
83,889
83,889
1.93
93.
1395
0.05
49
83,938
0
83,938
83,938
1.93
94
1410
0.05
49
83,986
0
83,986
83,986
1.93
95
1 1425
1 0.051
491
84,0351
01
84,035
1 84,0351
1.93
96
1 1440
1 0.051
49
1 84,083
1 01
84,083
84,083
1 1.93
Basin Depth Analysis
Page 18 of 18
A
B
C
D
1
RCFCD SYNTHETIC UNIT HYDROGRAPH
2
DATA INPUT SHEET
3
4
WORKSHEET PREPARED BY:
JAMES R. BAZUA;,
P.E.
5
6
PROJECT NAME
LA QUINTA RESORT
SPECIFIC PLAN AMENDMENT
7
TKC JOB #
2017110600
8
9
CONCENTRATION POINT DESIGNATION
1
10
AREA DESIGNATION
GOLF VILLAS
11
12
TRIBUTARY AREAS
ACRES
13
14
COMMERCIAL
15
PAVING /HARDSCAPE
16
SF - 1 ACRE
17
SF - 1/2 ACRE
18
SF - 1/4 ACRE
19
MF - CONDOMINIUMS
5.6
20
MF - APARTMENTS
21
MOBILE HOME PARK
22
LANDSCAPING
23
RETENTION BASIN
24
GOLF COURSE
25
MOUNTAINOUS
26
LOW LOSS RATE (PERCENT)
90%
27
28
LENGTH OF WATERCOURSE (L)
855
29
LENGTH TO POINT OPPOSITE CENTROID (Lca)
290
30
31
ELEVATION OF HEADWATER
1 43.7
32
ELEVATION OF CONCENTRATION POINT
40.6
33
1
34
AVERAGE MANN INGS'N' VALUE
0.02
35
36
STORM FREQUENCY (YEAR)
100
37
38
POINT RAIN
39
3 -HOUR
2.71
40
6 -HOUR
3.28
41
24 -HOUR
4.38
42
43
BASIN CHARACTERISTICS:
ELEVATION
AREA
44
45
46
47
48
49
50
51
52
PERCOLATION RATE (in /hr)
53
54
DRYWELL DATA
55
NUMBER USED
56
PERCOLATION RATE cfs
El
RCFCD SYNTHETIC UNIT HYDROGRAPH METHOD PROJECT:
BASIC DATA CALCULATION FORM TKC JOB #
SHORTCUT METHOD BY
LA QUINTA RESORT SPECIFIC PLAN AMENDMENT NO. 6, PLAI
2017110600
:S R. BAZUA, P.E. DATE 7/13/2009
DURATION
PHYSICAL DATA
6 -HOUR
24 -HOUR
EFFECTIVE RAIN (in)
[11 CONCENTRATION POINT
1.56
1.03
FLOOD VOLUME (cu -ft)
(acre -ft)
1
31,802
0.73
[21 AREA DESIGNATION
REQUIRED STORAGE (cu -ft)
(acre -ft)
36,281
0.83
31,539
0.72
GOLF VILLAS
PEAK FLOW (cfs)
[31 AREA - ACRES
10.62
1.86
MAXIMUM WSEL (ft)
5.600
4 L -FEET
855
5 L -MILES
0.162
6 La -FEET
290.00
[71 La -MILES
0.055
[81 ELEVATION OF HEADWATER
43.7
9 ELEVATION OF CONCENTRATION POINT
40.6
10 H -FEET
3.1
11 S -FEET /MILE
19.1
[121 S^0.5
4.38
13 L'LCA/S^0.5
0.002
1141 AVERAGE MANNINGS'N'
0.02
[151 LAG TIME -HOURS
0.05
16 LAG TIME - MINUTES
2.7
[171100% OF LAG- MINUTES
2.7
[181200% OF LAG-MINUTES
5.5
19 UNIT TIME - MINUTES 100 % -200% OF LAG
5
[24] TOTAL PERCOLATION RATE (cfs)
0.00
RAINFALL
DATA
[1] SOURCE
[2] FREQUENCY -YEARS 100
[3] DURATION:
3 -HOURS
6 -HOURS
24 -HOURS
[41
POINT
RAIN
INCHES
Plate E -5.2
[5]
AREA
(6)
[71
AVERAGE
POINT
RAIN
INCHES
[8]
POINT
RAIN
INCHES
Plate E -5.4
(9)
AREA
[101
[111
AVERAGE
POINT
RAIN
INCHES
[121
POINT
RAIN
INCHES
Plate E -5.6
(13)
AREA
[141
[15]
AVERAGE
POINT
RAIN
INCHES
2.71
5.600
1.00
2.711
3.28
5.600
1.00
3.28
4.38
5.600
1.00
4.38
0.00
0.00
1 0.00
0.00
0.00
0.00
0.00
0.00
1 0.00
0.00
0.00
0.00
0.00
0.00
1 0.00
0.00
0.00
0.00
SUM [5) 5.61 SUM (7)
It 61 AREA ADJ FACTOR
[17] ADJ AVG POINT RAIN
2.71
SUM [9] 5.601 SUM [11)
3.28
SUM [13] 1 5.60 SUM [15]
4.38
1.000
1.000
1.000
2.71
3.281
4.38
STORM EVENT
SUMMARY
DURATION
3 -HOUR
6 -HOUR
24 -HOUR
EFFECTIVE RAIN (in)
1.80
1.56
1.03
FLOOD VOLUME (cu -ft)
(acre -ft)
36,584
0.84
31,802
0.73
20,998
0.48
REQUIRED STORAGE (cu -ft)
(acre -ft)
36,281
0.83
31,539
0.72
20,824
0.48
PEAK FLOW (cfs)
13.21
10.62
1.86
MAXIMUM WSEL (ft)
Plate E -2.1
Page 2 of 18
r
I
RCFCD SYNTHETIC UNIT HYDROGRAPH METHOD
PROJECT LA QUINTA RESORT SPECIFIC PLAN AMENDMENT NO. 6, PLANNING
CONCENTRATION POINT: 1
BY MES R. BAZUA, P.E. DATE 7/13/2009
15,101JUSTED. LOSS RATE
SOIL
GROUP
Plate C -1
LAND USE
RI
NUMBER
Plate E-6.11
PERVIOUS
AREA
INFILTRATION
RATE
(in /hr)
rPlate E -6.2
DECIMAL
PERCENT
OF AREA
IMPERVIOUS
Plate E -6.3
ADJUSTED
INFILTRATION
RATE
(in /hr)
AREA
AVERAGE
ADJUSTED
INFILTRATION
RATE
(in /hr)
A
COMMERCIAL
32
0.74
90%
0.14
0.00
0.000
0.0000
A
PAVING /HARDSCAPE
32
0.74
100%
0.07
0.00
0.000
0.0000
A
SF - 1 ACRE
32
0.74
20%
0.61
0.00
0.000
0:0000
A
SF - 1/2 ACRE
32,
0.74
40%
0.47
0.00
0.000
0.0000
A
SF - 1/4 ACRE
32
0.74
50%
0.41
0.00
0.000
0.0000
A
MF - CONDOMINIUMS
32
0.74
65%
0.31
5.60
1.000
0.3071
A
MF - APARTMENTS
32
0.74
80%
0.21
0.00
0.000
0.0000
A
MOBILE HOME PARKS
32
0.74
75%
0.24
0.00
0.000
0.0000
A
LANDSCAPING
32
0.74
0%
0.74
0.00
0.000
0.0000
A
RETENTION BASINS
32
0.74
0%
0.74
0.00
0.000
0.0000
A
GOLF COURSE
32
0.74-
0%
0.74
0.00
0.000
0.0000
D
MOUNTAINOUS
93
0.95
90%
0.18
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
0.00
0.000
0.0000
SUMI 5.6 SUMI 0.3071
VARIABLE LOSS RATE CURVE 24 -HOUR STORM ONLY)
Fm= 0.15355
C= 0.00284
Ft= C(24- (T /60)) ^1.55 = 0.00284 (24- (T /60)) ^1.55 + 0.15 in /hr
LOW LOSS RATE (80 -90 PERCENT) = 90%
Where:
T =Time in minutes. To get an average value for each unit time period, Use T =1/2 the unit time for the first time period, ,
T =1 1/2 unit time for the second period, etc.
Plate E -2.1
Page 4 of 18
RCFCD SYNTHETIC UNIT HYDROGRAPH METHOD
100 YEAR - 3 HOUR STORM EVENT
PROJECT: LA QUINTA RESORT SPECIFIC PLAN AMENDMENT NO. 6, P
CONCENTRATION POINT: 1
BY: IES R. BAZUA, DATE 7/13/2009
EFFECTIVE
RAIN CALCULATION FORM
DRAINAGE AREA -ACRES 5.60
UNIT TIME - MINUTES 5
LAG TIME - MINUTES 2.73
UNIT TIME - PERCENT OF LAG 183.0
TOTAL ADJUSTED STORM RAIN - INCHES 2.71
CONSTANT LOSS RATE -in/hr 0.31
LOW LOSS RATE - PERCENT 90%
i
TOTAL PERCOLATION RATE (cfs) 0.00 cfs
Unit Time
Period
Time
Minutes Hours
Pattern
Percent
Plate E -5.9
Storm
Rain
in/hr
Loss Rate
in/hr
Max Low
Effective
Rain
in/hr
Flood
Hydrograph
Flow
cfs
Required
Storage
cf
1
5
0.08
1.3
0.423
0.31
0.38
0.12
0.65
194.31
2
10
0.17
1.3
0.423
0.31
0.38
0.12
0.65
194.31
3
15
0.25
1.1
0.358
0.31
0.32
0.05
0.28
85.04
4
20
0.33
1.5
0.488
1 0.31
0.44
0.18
1.01
303.58
5
25
0.42
1.5
0.488
0.31
0.44
0.18
1.01
303.58
6
30
0.50
1.8
0.585
0.31
0.53
0.28
1.56
467.48
7
35
0.58
1.5
0.488
0.31
0.44
0.18
1.01
303.58
8
40
0.67
1.8
0.585
0.31
0.53
0.28
1.56
467.48
9
45
0.75
1.8
0.585
0.31
0.53
0.28
1.56
467.48
10
50
0.83
1.5
0.488
0.31
0.44
0.18
1.01
303.58
11
55
0.92
1.6
0.520
0.31
0.47
0.21
1.19
358.21
12
60
1.00
1.8
0.585
0.31
0.53
0.28
1.56
467.48
13
65
1.08
2.2
0.715
0.31
0.64
0:41
2.29
686.01
14
70
1.17
2.2
0.715
0.31
0.64
0.41
2.29
686.01
15
75
1.25
2.2
0.715
0.31
0.64
0.41
2.29
686.01
16
80
1.33
2.0
0.650
0.31
0.59
0.34
1.92
576.74
17
85
1.42
2.6
0.846
0.31
0.76
0.54
3.02
904.55
18
90
1.50
2.7
0.878
0.31
0.79
0.57
3.20
959.18
19
95
1.58
2.4
0.780
0.31
0.70
0.47
2.65
795.28
20
100
1.67
2.7
0.878
0.31
0.79
0.57
3.20
959.18
21
105
1.75
3.3
1.073
0.31
0.97
0.77
4.29
1286.98
22
110
1.83
3.1
1.008
0.31
0.91
0.70
3.93
1177.71
23
115
1.92
2.9
0.943
0.31
0.85
0.64
3.56
1068.45
24
120
2.00
3.0
0.976
0.31
0.88
0.67
3.74
1123.08
25
125
2.08
3.1
1.008
0.31
0.91
0.70
3.93
1177.71
26
130
2.17
4.2
1.366
0.31
1.23
1.06
5.93
1778.68
27
135
2.25
5.0
1.626
0.31
1.46
1.32
7.39
2215.75
28
140
2.33
3.5
1.138
0.31
1.02
0.83
4.65
1396.25
29
145
2.42
6.8
2.211
0.31
1.99
1.90
10.66
3199.16
30
150
2.50
7.3
2.374
0.31
2.14
2.07
11.57
3472.32
31
155
2.58
8.2
2.667
0.31
2.40
2.36
13.21
3964.03
32
160
2.67
5.9
1.919
0.31
1.73
1.61
9.02
2707.45
33
165
2.75
2.0
0.650
0.31
0.59
0.34
1.92
576.74
34
170
2.83
1.8
0.585
0.31
0.53
0.28
1.56
467.48
35
175
2.92
1.8
0.585
0.31
0.53
0.28
1.56
467.48
36
180
3.00
0.6
0.195
0.31
0.18
0.02
0.11
32.78
EFFECTIVE RAIN & FLOOD VOLUMES SUMMARY
EFFECTIVE RAIN (in)
1.80
FLOOD VOLUME (acft)
0.84
FLOOD VOLUME (cult)
36583.58
REQUIRED STORAGE (acft)
0.83
REQUIRED STORAGE (cult)
36281.10
PEAK FLOW RATE (cfs)
13.21
Plate E -2.2
Page 6 of 18
RCFCD SYNTHETIC UNIT HYDROGRAPH METHOD
100 YEAR - 6 HOUR STORM EVENT
PROJECT: LA QUINTA RESORT SPECIFIC PLAN AMEN[
CONCENTRATION POINT: 1
BY: JAMES R. BAZ DATE: 7/13/2009
EFFECTIVE
RAIN CALCULATION FORM
DRAINAGE AREA -ACRES 5.60
UNIT TIME - MINUTES 5
LAG TIME - MINUTES 2.73
UNIT TIME - PERCENT OF LAG 183.0
TOTAL ADJUSTED STORM RAIN - INCHES 3.28
CONSTANT LOSS RATE -in/hr 0.307
LOW LOSS RATE - PERCENT 90%
TOTAL PERCOLATION RATE (cfs) 0.00 cis
Unit Time
Period
Time
Minutes Hours
Pattern
Percent
Plate E -5.9
Storm
Rain
in/hr
Loss Rate
in/hr
Max Low
Effective
Rain
in /hr
Flood
Hydrograph
Flow
cis
Required
Storage
cf
1
5
0.08
0.5
0.197
0.31
0.18
0.02
0.11
33.06
2
10
0.17
0.6
0.236
0.31
0.21
0.02
0.13
39.67
3
15
0.25
0.6
0.236
0.31
0.21
0.02
0.13
39.67
4
20
0.33
0.6
0.236
0.31
0.21
0.02
0.13
39.67
5
25
0.42
0.6
0.236
0.31
0.21
0.02
0.13
39.67
6
30
0.50
0.7
0.276.
0.31
0.25
0.03
0.15
46.29
7
35
0.58
0.7
0.276
0.31
0.25
0.03
0.15
46.29
8
40
0.67
0.7
0.276
0.31
0.25
0.03
0.15
46.29
9
45
0.75
0.7
0.276
0.31
0.25
0.03
0.15
46.29
10
50
0.83
0.7
0.276
0.31
0.25
0.03
0.15
46.29
11
55
0.92
0.7
0.276
0.31
0.25
0.03
0.15
46.29
12
60
1.00
0.8
0.315
0.31
0.28
0.01
0.04
13.07
13
65
1.08
0.8
0.315
0.31
0.28
0.01
0.04
13.07
14
70
1.17
0.8
0.315
0.31
0.28
0.01
0.04
13.07
15
75
1.25
0.8
0.315
0.31
0.28
0.01
0.04
13.07
16
80
1.33
0.8
0.315
0.31
0.28
0.01
0.04
13.07
17
85
1.42
0.8
0.315
0.31
0.28
0.01
0.04
13.07
18
90
1.50
0.8
0.315
0.31
0.28
0.01
0.04
13.07
19
95
1.58
0.8
0.315
0.31
0.28
0.01
0.04
13.07
20
100
1.67
0.8
0.315
0.31
0.28
0.01
0.04
13.07
21
105
1.75
0.8
0.315
0.31
0.28
0.01
0.04
13.07
22
110
1.83
0.8
0.315
0.31
0.28
0.01
0.04
13.07
23
115
1.92
0.8
0.315
0.31
0.28
0.01
0.04
13.07
24
120
2.00
0.9
0.354
0.31
0.32
0.05
0.26
79.20
25
125
2.08
0.8
0.315
0.31
0.28
0.01
0.04
13.07
26
130
2.17
0.9
0.354
0.31
0.32
0.05
0.26
79.20
27
135
2.25
0.9
0.354
0.31
0.32
0.05
0.26
79.20
28
140
2.33
0.9
0.354
0.31
0.32
0.05
0.26
79.20
29
145
2.42
0.9
0.354
0.31
0.32
0.05
0.26
79.20
30
150
2.50
0.9
0.354
0.31
0.32
0.05
0.26
79.20
31
155
2.58
0.9
0.354
0.31
0.32
0.05
0.26
79.20
32
160
2.67
0.9
0.354
0.31
0.32
0.05
0.26
79.20
33
165
2.75
1.0
0.394
0.31
0.35
0.09
0.48
145.32
34
170
2.83
1.0
0.394
0.31
0.35
0.09
0.48
145.32
35
175
2.92
1.0
0.394
0.31
0.35
0.09
0.48
145.32
36
180
100
1.0
0.394
0.31
0.35
0.09
0.48
145.32
37
185
108
1.0
0.394
0.31
0.35
0.09
0.48
145.32
38
190
3.17
1.1
0.433
0.31
0.39
0.13
0.70
211.44
39
195
3.25
1.1
0.433
0.31
0.39
0.13
0.70
211.44
40
200
3.33
1.1
0.433
0.31
0.39
0.13
0.70
211.44
41
205
3.42
1.2
0.472
0.31
0.43
0.17
0.93
277.57
42
210
150
1.3
0.512
0.31
0.46
0.20
1.15
343.69
43
215
3.58
1.4
0.551
0.31
0.50
0.24
1.37
409.82
44
220
3.67
1.4
0.551
0.31
0.50
0.24
1.37
409.82
45
225
3.75
1.5
0.590
0.31
0.53
0.28
1.59
475.94
46
230
3.83
1.5
0.590
0.31
0.53
0.28
1.59
475.94
47
235
3.92
1.6
0.630
0.31
0.57
0.32
1.81
542.07
48
240
4.00
1.6
0.630
0.31
0.57
0.32
1.81
542.07
49
245
4.08
1.7
0.669
0.31
0.60
0.36
2.03
608.19
50
250
4.17
1.8
0.708
0.31
0.64
0.40
2.25
674.32
51
255
4.25
1.9
0.748
0.31
0.67
0.44
2.47
740.44
52
260
4.33
2.0
0.787
0.31
0.71
0.48
2.69
806.57
53
265
4.42
2.1
0.827
0.31
0.74
0.52
2.91
872.69
54
270
4.50
2.1
0.827
0.31'
0.74
0.52
2.91
872.69
55
275
4.58
2.2
0.866
0.31
0.78
0.56
3.13
938.82
56
280
4.67
2.3
0.905
0.31
0.81
0.60
3.35
1004.94
Plate E -2.2
Page 7 of 18.
RCFCD SYNTHETIC UNIT HYDROGRAPH METHOD
100 YEAR - 6 HOUR STORM EVENT
PROJECT: LA QUINTA RESORT SPECIFIC PLAN AMENC
CONCENTRATION POINT: 1
BY: JAMES R. BAZ DATE: 7/13/2009
1.56
FLOOD VOLUME (acft)
EFFECTIVE
RAIN CALCULATION FORM
31802.28
REQUIRED STORAGE (acft)
0.72
DRAINAGE AREA -ACRES
UNIT TIME - MINUTES
LAG TIME - MINUTES
UNIT TIME - PERCENT OF LAG
TOTAL ADJUSTED STORM RAIN- INCHES
CONSTANT LOSS RATE -in/hr
LOW LOSS RATE - PERCENT
5.60
5
2.73
183.0
3.28
0.307
90%
TOTAL PERCOLATION RATE (cfs)
10.62
0.00 cfs
Unit Time
Period
Time
Minutes Hours
Pattern
Percent
Plate E -5.9
. Storm
Rain
in/hr
Loss Rate
in/hr
Max
Low
Effective
Rain
in/hr
Flood
Hydrograph
Flow
cfs
Required
Storage
cf
57
285
4.75
2.4
0.945
0.31
0.85
0.64
3.57
1071.07
58
290
4.83
2.4
0.945
0.31
0.85
0.64
3.57
1071.07
59
295
4.92
2.5
0.984
1 0.31
0.89
1 0.68
3.79
1137.19
60
300
5.00 --
2.6
1.023
1 0.31
0.92
0.72
4.01
1203.32 '
61
305
5.08
3.1
1.220
1 0.31
1.10
0.91
5.11
1533.94
62
310
5.17
3.6
1.417
1 0.31
1.28
1.11
6.22
1864:56
63
315
5.25.
3.9
1.535
0.31
1.38
1.23
6.88
2062.94
64
320
5.33
4.2
1.653
0.31
1.49
1.35
7.54
2261.31
65
325
5.42
4.7
1.850
0.31
1.66
1.54
8.64
2591.94
66
330
5.50
5.6
2.204
0.31
1.98
1.90
10.62
3187.06
67
335
5.58
1.9
0.748
0.31
0.67.
0.44
2.47
740.44 _
68
340
5.67
0.9
0.354
0.31
0.32
0.05
0.26
79.20
69
345
5.75
0.6
0.236
0.31
0.21
0.02
0.13
39.67
70
350
5.83
0.5
0.197
0.31
0.18
0.02
0.11
33.06
71
355
5.92
0.3 _
0.118
0.31
0.11
0.01
0.07
19.84
72.
360
6.00
.0.2
0.079
0.31
0.07
0.01
0.04
13.22
f,
EFFECTIVE RAIN 8 FLOOD VOLUMES SUMMARY
EFFECTIVE RAIN (in)
1.56
FLOOD VOLUME (acft)
0.73
FLOOD VOLUME (cult)
31802.28
REQUIRED STORAGE (acft)
0.72
REQUIRED STORAGE (cult)
31539.33
PEAK FLOW RATE (cfs)
10.62
I
Plate E -2.2
Page 8 of 18
r
RCFCD SYNTHETIC UNIT HYDROGRAPH METHOD
100 YEAR - 24 HOUR STORM EVENT
PROJECT: LA OUINTA RESORT SPECIFIC PLAN AMEND
CONCENTRATION POINT: 1
BY: JAMES R. BAZ DATE: .7/13/2009
EFFECTIVE RAIN CALCULATION FORM
DRAINAGE AREA -ACRES 5.600
UNIT TIME - MINUTES 15
LAG TIME - MINUTES 2.73
UNIT TIME - PERCENT OF LAG 549.1
TOTAL ADJUSTED STORM RAIN- INCHES 4.38
CONSTANT LOSS RATE -in/hr n/a
VARIABLE LOSS RATE (AVG) inthr 0.3071
MINIMUM LOSS RATE (for var. loss) - in/hr 0.154
LOW LOSS RATE - DECIMAL 0.90
C 0.00284
PERCOLATION RATE cis 0.00
Unit Time
Period
Time
Minutes Hours
Pattern
Percent
Plate E -5.9
Storm
Rain
in/hr
Loss Rate
in/hr
Max Low
Effective
Rain
in/hr
Flood
Hydrograph
Flow
cfs
Required
Storage
cf
1
15
0.25
.0.2
0.035
0.542
0.032
0.004
0.02
17.66
2
30
0.50
0.3
0.053
0.536
0.047
0.005
0.03
26.49
-3
45
0.75
0.3
0.053
0.530
0.047
0.005
0.03
26.49
4
60
1.00
0.4
0.070
0.524
0.063
0.007
0.04
35.32
5
75
1.25
0.3.
0.053
0.517
0.047
0.005
0.03
26.49
6
.90
1.50
0.3
0.053
0.511
0.047
0.005
0.03
26.49
7..
105
1.75
0.3
0.053
0.505
0.047
0.005
0.03
26.49
8
120
2.00
0.4
0.070
0.499
0.063
0.007
0.04
35.32
9
135
2.25
0.4
0.070
0.493.
0.063
0.007
0.04
35.32
10
150
2.50 >
0.4 _
0.070
0.487
0.063
0.007
0.04 1
35.32
11
165
2.75
0.5
.0.088
0.481
0.079
0.009
0.05
44.15
12
180
3.00
0.5
0.088
0.475
0.079
0.009
0.05
44.15
13
195
3.25
0.5
0.088
0.469
0.079
0.009
0.05
44.15
14
210
3.50
0.5...
0.088
0.463
.0.079
0.009
0.05
44.15
15
225
3.75
0.5
0.088
0.458
0.079
0.009
0.05
44.15
16
240
4.00
0.6
0.105
0.452
0.095
0.011
0.06
•52.98
17
255
4.25
0.6.
0.105
0.446
0.095
0.011
0.06
52.98
18
270
4.50
0.7
0.123
0.440
0.110
0.012
0.07
61.81
19
285
4.75
0.7 _
0.123
0.435
0.110
0.012
0.07
61.81
20
300
5.00
0.8
0.140
0.429 -
0.126
0.014
0.08
70.64
21
315
5.25
0.6
0.105
0.424
0.095
0.011
0.06
52.98
22
330
5.50
0.7
0.123
0.418
0.110
0.012
0.07
61.81
23
345
5.75
0.8
0.140
0.413
0.126
0.014
0.08
70.64
24
360
6.00
0.8
0.140
0.407
0.126
0.014
0.08
70.64
25
375
6.25
0.9
0.158
0.402
0.142
0.016
0.09
79.47
26
390
6.50
0.9
0.158
0.396
0.142
0.016
0.09
79.47
27
405
6.75
1.0
0.175
0.391
0.158
0.018
0.10
88.30
28
420
7.00
1.0
0.175
0.386
0.158
0.018
0.10
88.30
29
435
7.25
1.0
0.175
0.381
0.158
0.018
0.10
88.30
30
450
7.50
1.1
0.193
0.375
0.173
0.019
0.11
97.13
31
465
7.75
1.2
0.210
0.370
0.189
0.021
0.12
105.96
32
480.
8.00
1.3
0.228
0.365
1 0.205
0.023
0.13
114.79
33
495
8.25
1.5
0.263
0.360
1 0.237
0.026
0.15
132.45
34
510
8.50
1.5
0.263
0.355
0.237
0.026
0.15
132.45
35
525
8.75
1.6
0.280
0.350
0.252
0.028
0.16
141.28
36
540
9.00
1.7
0.298
0.345
0.268
0.030
0.17
150.11
37
555
9.25
1.9
0.333
0.340
0.300
0.033
0.19
167.77
38
570
9.50
2.0
0.350
0.335
0.315
0.015
0.08
75.51
39
585
9.75
2.1
0.368
0.331
0.331
0.037
0.21
187.99
40
600
10.00
2.2
0.385
0.326
0.347
0.060
0.33
300.23
41
615
10.25
1.5
0.263
0.321
1 0.237
0.026
0.15
132.45
42
630
10.50
1.5
0.263
0.317
0.237
0.026
0.15
132.45
43
645
10.75
2.0
0.350
0.312
0.315
0.039
0.22
194.05
44
660
11.00
2.0
0.350
0.307
0.315
0.043
0.24
217.05
45 _
675
11.25
1.9
0.333
0.303
0.300
0.030
0.17
151.52
46
690
11.50
1.9
0.333
0.298
0.300
0.035
0.19
174.04
47
705
11.75
1.7
0.298,
0.294
0.268
0.004
0.02
19.71
48
720
12.00
1.8
0.315
0.290
0.284
0.026
0.14
130.04
49
735
12.25
2.5
0.438
0.285
0.394
0.153
0.86
769.93
50
750
12.50
2.6
0.456
0.281
0.410
0.175
0.98
879.77
51
765
12.75
2.8
0.491
0.277
0.442
0.214
1.20
1077.65
52
780
13.00
2.9
0.508
0.273
0.457
0.236
1.32
1186.97
53
795
13.25
3.4
0.596
0.268
0.536
0.327
1.83
1649.24
54
810
13.50
3.4
0.596
0.264
0.536
0.331
1.86
1669.74
55
825
13.75
2.3
0.403
0.260
0.363
0.143
0.80
718.67
56
840
14.00
2.3
0.403
0.256
0.363
0.147
0.82
738.65
57
855
14.25
2.7
0.473
0.252
0.426
0.221
1.24
1111.55
58
870
14.50
2.6
0.456
0.249
0.410
0.207
1.16
1042.68
59
885
14.75
2.6
0.456
0.245
0.410
0.211
1.18
1061.84
60
900
15.00
2.5
0.438
0.241
0.394
0.197
1.10
992.42
61
915
15.25
2.4
0.420
0.237
0.378
0.183
1.03
922.71
62
930
15.50.
2.3
0.403
0.234
0.363
0.169
0.95
852.72
63
945
15.75,
1.9
0.333
0.230
0.300
0.103
0.58
517.53
64
960
16.00
1.9
0.333
0.227
0.300
0.106
0.59
535.26
65
975
16.25
0.4
0.070
0.223
0.063
0.007
0.04
35.32
66
990
16.50
0.4
0.070
0.220
0.063
0.007
0.04
35.32
67
1005
16.75
0.3
0.053
0.216
0.047
0.005
0.03
26.49
VIENT NO. 6,'F
0
)
III .
Plate E -2.2
Page 9 of 18
1
J.
rr•
DRAINAGE AREA -ACRES 5.600
UNIT TIME - MINUTES 15
LAG TIME - MINUTES 2.73
UNIT TIME - PERCENT OF LAG 549.1
TOTAL ADJUSTED STORM RAIN - INCHES 4.38
RCFCD SYNTHETIC UNIT HYDROGRAPH METHOD
100 YEAR - 24 HOUR STORM EVENT
PROJECT: v LA QUINTA RESORT SPECIFIC PLAN AMEN[
CONCENTRATION POINT: 1
BY: JAMES R. BAZ DATE: 7/13/2009
EFFECTIVE RAIN CALCULATION FORM
DRAINAGE AREA -ACRES 5.600
UNIT TIME - MINUTES 15
LAG TIME - MINUTES 2.73
UNIT TIME - PERCENT OF LAG 549.1
TOTAL ADJUSTED STORM RAIN - INCHES 4.38
CONSTANT LOSS RATE - in/hr n/a
VARIABLE LOSS RATE (AVG) in/hr 0.3071
MINIMUM LOSS RATE (for var. loss) - in/hr 0.154
LOW LOSS RATE - DECIMAL 0.90
C 0.00284
PERCOLATION RATE cfs 0.00 .
Unit Time
Period
Time
Minutes Hours
Pattern
Percent
Plate E -5.9
Storm
Rain
in/hr
Loss Rate
in/hr
Max Low
Effective
Rain
in/hr
Flood
Hydrograph
Flow
cfs
Required
Storage
cf
68
1020
17.00
0.3
0.053
0.213
0.047
01005
0.03
26.49
69
1035
17.25
0.5
0.088
0.210
0.079
0.009
0.05
44.15
70
1050
17.50
0.5
0.088
0.207
0.079
0.009
0.05
44.15
71
1065
17.75
0.5.
0.088
0.204
0.079
1 01009
0.05
44.15
72
1080
18.00,
0.4
0.070
0.201
0.063
0.007
0.04
35.32
73
1095
18.25
0.4
0.070
0.198
0.063
0.007
0.04
35.32
74
1110
,18.50
0.4
0.070
0.195
0.063
0.007
0.04
35.32
75
1125
18.75
0.3
0.053
0.192
0.047
0.005
0.03
26.49
76
1140
.19.00
0.2
0.035
0.189
0.032
0.004
0.02
17.66
77
1155
19.25
0.3
0.053
.0.187
.0.047
0.005
0.03
26.49
78,
1170
19.50
0.4
0.070
0.184
0.063
0.007
0.04
35.32
79
1185
19.75
0.3
0.053
0.182
0.047
1 0.005
0.03
26.49
80
1200
20.00
0.2
0.035
.0.179
0.032
0.004
0.02
17.66
81
1215
20.25
0.3
0.053
0.177
0.047
0.005
0.03
26.49
82
1230
20.50
0.3
0.053
0.174
0.047
2.005
0.03
26.49
83
1245
20.75
0.3
0.053
0.172
0.047
0.005
0.03
26.49
84
1260
21.00 _
0.2
0.035
0.170
0.032
0.004
0.02
17.66
85
1275
21.25
0.3
0.053
0.168
0.047
0.005
0.03
26.49
86
1290
21.50
0.2
0.035
0.166
0.032
0.004
0.02
17.66
87
1305
21.75
0.3
0.053
0.164
0.047
0.005
0.03
26.49
88
1320
22.00
0.2-
0.035
0.163
0.032
0.004
0.02
17.66
89
1335
22.25
0.3
0.053
0.161
0.047
0.005
0.03
26.49
90
1350
22.50
0.2
0.035
0.160
0.032
0.004
0.02
17.66
91
1365
22.75
0.2
0.035-
0.158
0.032
0.004
0.02
17.66
92
1380
-23.00
0.2
0.035
0.157
0.032
0.004
0.02
17.66
93
1395
23.25
0.2
0.035
0.156
0.032
0.004
0.02
17.66
94
1410
23.50
.0.2
0.035
0.155
0.032
0.004
0.02
17.66
95
1425
23.75.
0.2
1 0.035
0.154
0.032
0.004
0.02
17.66
96
1440.
..24.00 ,
0.2
0.035
0.154.
0.032.
0.004
0.02
17.66
MENT NO. 6, F
EFFECTIVE RAIN & FLOOD VOLUMES SUMMARY
'
V EFFECTIVE RAIN (in)
1.03
FLOOD VOLUME (acft)
0.48
FLOOD VOLUME (cuft)
20997.91
REQUIRED STORAGE (actt)
0.48
REQUIRED STORAGE (cult)
20824.29
PEAK FLOW cis
1.86'
r
r
+
r
,
r
r
Plate E -2.2
Page 10 of 18
r
N
1
TKC JOB # 2017110600
ion YFAR -1 H011R STORM FVFNT
TIME
UNIT (min)
PERIOD
FLOW
IN
cfs
VOLUME
IN
cult
TOTAL IN
BASIN
cult
PERC
OUT
cult
TOTAL IN
BASIN
cult
BASIN
DEPTH
ft
BALANCE IN
BASIN
cult acre -ft
1
5
0.65
194
194
0
194
194
0.00
2
10
0.65.
194
389
0
389
389
0.01
3
15
0:28
85
474
0
474
474
0.01
4
20
.1.01
304
777
0
777
777
0.02
5
25
1.01
304
1,081
0
1,081
1,081
0.02
6
30
1.56
467
1,548
0
1,548
1,548
0.04
7
35
1.01
304
1,852
0
1,852
-
1,,852
0.04
8
40
1.56
467
2,319
0
2,319
-
2,319
0.05
9
45
1.56
467
2,787
0
_ 2,787
-
2,787
0.06
10
50
1.01
304
3,090
01
3,090
-
3,090
0.07
11
.55
1.19
358
3,449
0
3,449
-
3,449
0.08
12
60
1.56
467
3,916
0
3,916
-
3,916
0.09
13
65
2.29
686
4,602
0
4,602
4,602
0.11
14
70
2.29
686
5,288
0
5,288
5,288
0.12
15
75
2.29
686
5,974
0
5,974
5,974
0.14
16,
80
1.92
577
6,551
0
6,551
-
6,551
0.15
17,
85
3.02
905
7,455
0
7,455
-
7,455
0.17
18,
90
3.20
959
8,415
0
8,415
-
8,415
0.19
19
95
2.65
795
9,210
0
9,210
9,210
0.21
20,
100
3.20
959
10,169
0
10,169
10,169
0.23
21
105
4.29
1,287
11,456
0
11,456
11,456
0.26
22
110
3.9.3
1,178
12,634
0
12,634
12,634
0.29
23
115
3.56
1,068
13,702
0
13,702
13,702
0.31
` 24
120
3.74
1,123
14,825
0
14,825
14,825
0.34
25
125
3.93
1,178
16,003
0
16,003
-
16,003
0.37
26
130
5.93
1,779
17,782
0
17,782
-
17,782
0.41
27
135
7.39.
2,216
19,997
0
19,997
-
19,997
0.46
28
140
4.65
1,396
21,394
0
21,394
-
21,394
0.49
29
145
10.66
3,199
24,593
0
24,593
-
24,593
0.56
30
150
11.57
3,472
28,065
0
28,065
-
28,065
0.64
31
155
13.21
3,964
32,029
0
32,029
-
32,029
0.74
32
160
9.02
2,707
34,737
0
34,737
-
34,737
0.80
33
165
1.92
577
35,313
01
35,313
-
35,313
0.81
34
170
1.56
467
35,781
01
35,781
1 -
35,781
0.82
35
175
1.56
467
36,248
01
36,248
1
36,248
0.83
36
180
0.11
33
36,281
01
36,281
1
36,281
0.83
Basin Depth Analysis
Page 14 of 18
1
TKC JOB # 2017110600
100 YEAR - 6 HOUR STORM EVENT
TIME
UNIT (min)
PERIOD
FLOW
IN
cfs
VOLUME
IN
cult
TOTAL IN
BASIN
cuff
PERC
OUT
cult
TOTAL IN
BASIN
cult
BASIN
DEPTH
ft
BALANCE IN
BASIN
cult acre -ft
1
5
0.11
33
33
0
33
33
0.00
2
10
0.13
40
73
0
73
73
0.00
3
15
0.13
40
112
0
112
112
0.00
4
20
0.13
40
152
01
152
152
0.00
5
25
0.13
40
192
01
192
192
0.00
6
30
0.15
46
238
0
238
-
238
0.01
7
35
0.15
46
284
0
284
284
0.01
8
40
0.15
46
331
0
331
-
331
0.01
9
45
0.15
46
377
0
377
-
377
0.01
10
50
0.15
46
423
0
423
-
423
0.01
11
55
0.15
46
469
0
.469
469
0.01
12
60
0.04
13
483
0
483
483
0.01
13
65
0.04
13
496
0
496
-
496
0.01
14
70
0.04
13
509
0
509
509
0.01
15
75
0.04
13
522
0
522
522
0.01
16
80
0.04
13
535
0
535
535
0.01
17
85
0.04
13
548
0
548
548
0.01
18
90
0.04
13
• 561
0
561
561
0.01
19
95
0.04
13
574
0
574
574
0.01
20
100,
0.04
13
587
0
587
-
587
0.01
21
105
0.04
13
600
0
600
600
0.01
22
110
0.04
13
613
0
613
613
0.01
23
115
0.04
13
626
0
626
626
0.01
24
120
0.26
79
706
0
706
706
0.02
25
125
0.04
13
719
0
719
719
0.02
26
130
0.26
79
798
0
798
798
0.02
27
135
0.26
79
877
0
877
877
0.02
28
140
0.26
79
956
0
956
956
0.02
29
145
0.26
79
1,035
0
1,035
-
1,035
0.02
30
150
0.26
79
1,115
0.
1,115
1,115
0.03
31
155
0.26
79
1,194
0
1,194
1,194
0.03
32
160
0.26
79
1,273
0
1,273
1,273
0.03
33
165
0.48
145
1,418
0
1,418
1,418
0.03
34
170
0.48
145
1,564
0
1,564
1,564
0.04
35
175
0.48
145
1,709
0
1,709
1,709
0.04
36
180
0.48
145
1,854
0
1,854
-
1,854
0.04
37
185
0.48
145
2,000
01
2,000
-
2,000
0.05
38
190
0.70
211
2,211
0
2,211
2,211
0.05
39
195
0.70
211
2,422
0
2,422
2,422
0.06
40
200
0.70
211
2,634
0
2,634
2,634
0.06
41
205
0.93
278
2,911
0
2,911
2,911
0.07
42
210
1.15
344
3,255
0
3,255
3,255
0.07
43
215
1.37
410
3,665
0
3,665
-
.3,665
0.08
44
220
1.37
410
4,075
0
4,075
-
4,075
0.09
45
225
1.59
476
4,551
0
4,551
-
4,551
0.10
46
230
1.59
476
5,027
0
5,027
-
5,027
0.12
47
235
1.81
542
5,569
0
5,569
-
5,569
0.13
48
240
1.81
542
6,111
0
6,111
-
6,111
0.14
49
245
2.03
608
6,719
0
6,719
6,719
0.15
50
250
2.25
674
7,393
0
7,393
7,393
0.17
51
255
2.47
740
8,134
0
8,134
-
8,134
0.19
52
260
2.69
807
8,940
0
8,940
-
8,940
0.21
53
265
2.91
873
9,813
0
9,813
-
9,8131
0.23
54
270
2.91
873
10,686
0
10,686
-
10,686
0.25
55
275
3.13
939
11,625
0
11,625
-
11,625
0.27
Basin Depth Analysis
Page 15 of 18
1
1
TKC JOB # 2017110600
100 YEAR - 6_HOUR STORM EVENT
l
TIME
UNIT (min)
PERIOD.
FLOW
IN
cfs
VOLUME
IN
cult
TOTAL IN
BASIN
cult
PERC
OUT
cult
TOTAL IN
BASIN
cult
BASIN
DEPTH
ft
BALANCE IN
BASIN
cult acre -ft
56
280,
3.35
1,005
12,629
0
12,629
12,629
0.29
57
285.
3.57
1,071
13,701
0
13,701
13,701
0.31
58
290
3.57
1,071
14,772
0
14,772
14,772
0.34
59
295
3.79
1,137
15,909
0
15,909
15,909
0.37
60
300
4.01
.. .. 1,203
17,112
0
17,112
17,112
0.39
61
305
5.11.
1,534
18,646
0
18,646
18,646
0.43
62
310
6.22
1,865
20,511
0
20,511
20,511
0.47
63
315
6.88
2,063
22,574
0
22,574
22,574
0.52
64
.320.
7.54
2,261
24,835
0
24,835
24,835
0.57
65
325
8.64
2,592
27,427
0
27,427
27,427
0.63
66
330
10.62
3,187
30,614
0
30,614
30,614
0.70
67
335
2.47
740
31,354
0
31,354
31,354
'.0.72
68
340
.0.26
79
.31,434
0
.31,434
31,434.
0.72
69
345
0.13
40
31,473
0
31,473
31,473
0.72
70
350
0.11
33
31,506
0
31,506
31,506
0.72
71,
355
.0.07
20
31,526
01
31;526
31,526
0.72
72.
360
0.04
13
31,539
1 01
31,539
31,539
0.72
1
TKC JOB # 2017110600
inn YFAR -9A HOI A STORM FVFNT
TIME
UNIT (min)
PERIOD
FLOW
IN
cfs
VOLUME
IN
cult
TOTAL IN
BASIN
cult
PERC
OUT
cult )
TOTAL IN
BASIN
(cuft)
BASIN
DEPTH
ft
BALANCE IN
BASIN
cult acre -ft
1
15
0.02
18
18
0
18
18
0.00
2
30
0.03
26
44
0
44
44
0.00
3
45
0.03
26
71
0
71
71
0.00
4
60
0.04
35
106
0
106
106
0.00
5
75
0.03
26
132
0
132
132
0.00
6
90
0.03
26
159
0
159
159
0.00
7
105
0.03
26
185
0
185
185
0.00
8
120
0.04
35
221
0
221
221
0.01
9
135
0.04
35
256
0
256
256
0.01
10
150
0.04
35
291
0
291
291
.0.01
11
165
0.05
44
336
0
336
336
0.01
12
180
0.05
44
380
0
380
380
0.01
13
195
0.05
44
424
0
424
424
0.01
14
210
0.05
44
468
0
468
468
0.01
15
225
0.05
44
512
0
512
512
0.01
16
240
0.06
53
565
0
565
565
0.01
17
255
0.06
53
618
0
618
618
0.01
18
270
0.07
62
680
0
680
680
0.02
19
285
0.07
62
742
0
742
742
0.02
20
300
0.08
71
812
0
812
812
0.02
21
315
0.06
53
865
0
865
865
0.02
22
330
0.07
62
927
0
927
927
0.02
23
345
0.08
71
998
0
998
998
0.02
24
360
0.08
71
1,068
0
1,068
1,068
0.02
25
375
0.09
79
1,148
0
1,148
1,148
0.03
26
390
0.09
79
1,227
0
1,227
1,227
0.03
27
405
0.10
88
1,316
0
1,316
1,316
0.03
28
420
0.10
88
1,404
0
1,404
1,404
0.03
29
435
0.10
88
1,492
0
1,492
1,492
0.03
30
450
0.11
97
1,589
0
1,589
1,589
0.04
31
465
0.12
106
1,695
0
1,695
1,695
0.04
32
480
0.13
115
1,810
0
1,810
1,810
0.04
33
495
0.15
132
1,943
0
1,943
1,943
0.04
34
510
0.15
132
2,075
0
2,075
2,075
0.05
35
525
0.16
141
2,216
0
2,216
2,216
0.05
36
540
0.17
150
2,366
0
2,366
2,366
0.05
37
555
0.19
168
2,534
0
2,534
2,534
0.06
38
570
0.08
76
2,610
0
2,610
2,610
0.06
39
585
0.21
188
2,798
0
2,798
2,798
0.06
40
600
0.33
300
3,098
0
3,098
3,098
0.07
41
615
0.15
132
3,230
0
3,230
3,230
0.07
42
630
0.15
132
3,363
0
3,363
3,363
0.08
43
645
0.22
194
3,557
0
3,557
3,557
0.08
44
660
0.24
217
3,774
0
3,774
3,774
0.09
45
675
0.17
152
3,925
0
3,925
3,925
0.09
46
690
0.19
174
4,100
0
4,100
4,100
0.09
47
705
0.02
20
4,119
0
4,119
4,119
0.09
48
720
0.14
130
4,249
0
4,249
4,249
0.10
49
735
0.86
770
5,019
0
5,019
5,019
0.12
50
750
0.98
880
5,899
0
5,899
5,899
0.14
51
765
1.20
1,078
6,977
0
6,977
6,977
0.16
52
780
1.32
1,187
8,164
0
8,164
8,164
0.19
53
795
1.83
1,649
9,813
0
9,813
9,813
0.23
54
810
1.86
1,670
11,483
0
11,483
11,483
0.26
55
825
0.80
719
12,201
0
12,201
12,201
0.28
56
840
0.82
739
12,9401
0
12,940
12,940
0.30
57
855
1.24
1,112
14,051
0
14,051
14,051
0.32
58
870
1.16
1,043
15,094
0
15,094
15,094
0.35
Basin Depth Analysis
Page 17 of 18
1
TKC JOB # 2017110600
1nn VFGR - 7d W01 IR CTr1RM FVFNT
TIME
UNIT (min)
PERIOD
FLOW
IN
cfs
VOLUME
IN
cult
TOTAL IN
BASIN
cult
PERC
OUT
cult
TOTAL IN
BASIN
cult
BASIN
DEPTH
ft
BALANCE IN
BASIN
cult acre -ft
59
885
1.18
1,062
16,156
0
16,156
16,156
0.37
60
900
1.10
992
17,148
0
17,148
17,148
0.39
61
915
1.03
923
18,071
0
18,071
18,071
0.41
62
930
0.95
853
18,924
0
18,924
18,924
0.43
63
945
0.58
518
19,441
0
19,441
19,441
0.45
64
960
0.59
535
19,977
0
19,977
19,977
0.46
65
975
0.04
35
20,012
0
20,012
20,012
0.46
66
990
0.04
35
20,047
0
20,047
20,047
0.46
67
1005
0.03
26
20,074
0
20,074
20,074
0.46
68
1020
0.03
26
20,100
0
20,100
20,100
0.46
69
1035
0.05
44
20,144
0
20,144
20,144
0.46
70
1050
0.05
44
20,189
0
20,189
20,189
0.46
71
1065
0.05
44
20,233
0
20,233
20,233
0.46
72
1080
0.04
35
20,268
0
20,268
20,268
0.47
73
1095
0.04
35
20,303
0
20,303
20,303
0.47
74
1110
0.04
35
20,339
0
20,339
20,339
0.47
75
1125
0.03
26
20,365
0
20,365
20,365
0.47
76
1140
0.02
18
20,383
0
20,383
20,383
0.47
77
1155
0.03
26
20,409
0
20,409
20,409
0.47
78
1170
0.04
35
20,445
0
20,445
20,445
0.47
79
1185
0.03
26
20,471
0
20,471
20,471
0.47
80
1200
0.02
18
20,489
0
20,489
20,489
0.47
81
1215
0.03
26
20,515
0
20,515
20,515
0.47
82
1230
0.03
26
20,542
0
20,542 •
20,542
0.47
83
1245
0.03
26
20,568
0
20,568
20,568
0.47
84
1260
0.02
.18
20,586
0
20,586
20,586
0.47
85
1275
0.03
26
20,612
0
20,612
20,612
0.47
86
1290
0.02
18
20,630
0
20,630
20,630
0.47
87
1305
0.03
26
20,657
0
20,657
20,657
0.47
88
1320
0.02
18
20,674
0
20,674
20,674
0.47
89
1335
0.03
26
20,701
0
20,701
20,701
0.48
90
1350
0.02
18
20,718
0
20,718
20,718
0.48
91
1365
0.02
18
20,736
0
20,736
20,736
0.48
92
1380
0.02
18
20,754
0
20,754
20,754
0.48
93
1395
0.02
18
20,771
0
20,771
20,771
0.48
94
1410
0.021
18
20,789.
0
20,789
20,7891
0.48
95 •
1425-T
0.021
18
20,807
1 0
20,807
20,807
0.48
96
1440
0.02
18
20,824
0
20,824
1
20,824
1 0.48
I
4
Basin Depth Analysis
Page 18 of 18
ti
y
� CONCLUSIONS AND
RECOIVIMENDATIONS
CONCLUSIONS AND RECOMMENDATIONS
SPA VILLAS (A PORTION OF SUBAREA B)
Recalculation of the projected runoff totals for each of the "on- site" subareas (see MDS
' "On= Site" Hydrology Map, included) represented in the original 1998 MDS report is beyond
the scope of this SP/EIR level report. However new totals based on current City of La Quinta
standards can be expected to be greater than the totals given in the original report. Since the
' same type of analyses and methodology are employed in both reports, the reason for the
increase can be attributed to the following:
' 1. Current NOAA rainfall intensities accepted for use by the City of La Quinta are
significantly greater than the rainfall intensities used in the original 1998 MDS
Hydrology Report to calculate the amount of on -site runoff.
' 2. Moderately saturated conditions must be assumed for the 10 year storm event (AMC
2) and completely saturated for the 100 year storm event (AMC 3) per City of La
Quinta standards. The original MDS report appears to have assumed dry conditions
(AMC 1) for the entire on -site basin.
' A comparison of Riverside County Rational Method calculations using design criteria
obtained from the 1998 MDS Hydrology Report vs. currently accepted design criteria,
applied over the same area, indicates that an 80% increase in estimated runoff totals can be
expected when using the latest design criteria. Based on the original MDS Hydrology Report
calculations, the backbone portion of the existing Calle Obregon storm drain system flows
a below half capacity during the 100 year storm event. Therefore, it is feasible that the Calle
' Obregon storm drain system can convey the projected 100 year runoff for the same area
based on current standards. Because of the large number of curb inlets spaced at relatively
short intervals along Calle Obregon, it is unlikely that the capacity of the curb inlets or the
street cross section will be exceeded based on current discharge calculation standards.
Nevertheless, on -site retention is recommended (see Hydrology Map, included) for the
' easterly portion of the Spa Villas development since it appears to be located in an area
that makes it relatively difficult for a proposed drainage system to follow existing
drainage patterns. The surrounding parcels have been developed since the original storm
1 drain system was installed and the proposed Spa Villas are not immediately adjacent to the
existing storm drain system.
' GROVE UNITS, MORGAN HOUSE, WELLNESS CENTER (A PORTION OF
SUBAREA B)
The proposed Grove Units, Morgan House and Wellness Center development area is located
within the "on- site" drainage basin defined in the original 1998 MDS Hydrology Report. As
mentioned previously in this report, runoff totals based on current City of La Quinta
standards can be expected to be greater than the totals given in the MDS report for areas
within the "on- site" basin. Since the same type of analyses and methodology are employed
in both reports, the reason for the increase can be attributed to the following:
1. Current NOAA rainfall intensities accepted for use by the City of La Quinta are
J
significantly greater than the rainfall intensities used in the original 1998 MDS
Hydrology Report to calculate the amount of on -site runoff.
2. Moderately saturated conditions must be assumed for the 10 year storm event (AMC
2) and completely saturated for the 100 year storm event (AMC 3) per City of La
Quinta standards. The original MDS report appears to have assumed dry conditions
(AMC 1) for the entire on -site basin.
The proposed Grove Units, Morgan House and Wellness Center area is best suited to
drain to the adjacent backbone storm drain system located along Calle Obregon, which
is immediately adjacent to the proposed development area. A comparison of Riverside
County Rational Method calculations using design criteria obtained from the 1998 MDS
Hydrology Report vs. currently accepted design criteria, applied over the same area, indicates
that an 80% increase in estimated runoff totals can be expected when using the latest design
criteria. Based on the original MDS Hydrology Report flowrate calculations and the included
pipe calculations, the backbone portion of the existing on -site storm drain system flows
below half capacity during the 100 year storm event. Therefore, the on -site storm system can
be expected to convey the projected 100 year runoff for the same area based on current
standards. Because of the large number of curb inlets spaced at relatively short intervals
along Calle Obregon, it is unlikely that the capacity of the curb inlets or the street cross
section will be exceeded based on current discharge calculation standards.
HOTEL /CONFERENCE CENTER EXPANSION (SUBAREA C)
The limits of the tributary area that drain to the common 24" mainline storm drain have been
established based on several site visits and a field survey. This tributary area, known as
Subarea C is represented on the Hydrology Map included in the Appendix portion of this
report. The total of 15.4 acres in area contributes runoff to the existing 24" mainline system,
including a portion of the existing hotel suites to the east of the proposed Hotel /Conference
Center development. Storm runoff calculations contained in this report for the
Hotel /Conference Center development area produce a 100 year discharge of approximately
67 CFS. Street Improvement Plans approved in October 2008 for the La Quinta Resort and
Spa indicate that an addition 3.1 CFS is introduced to the mainline system along the existing
entry drive.
A hydraulic analysis of the existing 24" mainline storm drain pipe shows that even under
optimum conditions, the maximum capacity of the pipe is less than 19 CFS. The existing
pump system used to transfer flows from the 24" storm drain pipe into the existing force
main system consists of two individual pumps, each capable of pumping 450 GPM (1.0
CFS) at peak performance. Clearly, the existing storm drain system does not have the
capacity to convey the total runoff from the proposed Hotel /Conference Center development
area during the 100 year (or 10 year) storm event.
.,
On -site retention (underground) is recommended within the Hotel /Conference Center
Expansion development area in order to satisfy City of La Quinta standards for
drainage design during the 100 year storm event.
GOLF VILLAS (SUBAREA C)
City of La Quinta standards prohibit an increase in storm flows introduced to Eisenhower
' Drive, generated by the proposed Golf Villas Development. In fact, introduction of runoff
from a private development into the public right of way is an atypical condition that is
discouraged based on City of La Quinta standards.
' The proposed development does not constitute a change in the type of land use, and the
amount of runoff generated by the Golf Villas is not expected to increase in the post
1 development condition. Original hydrology study information used to design the existing
drainage facilities for this area could not be obtained for comparison. However, it is likely
that new runoff totals generated using current City of La Quinta standards would be greater
than totals obtained during the design of the existing development. Current .City of La
Quinta standards require the use of NOAA rainfall intensity figures when calculating
discharge values, whereas older designs are usually based on Riverside County Hydrology
Manual figures, which tend to be less conservative.
1On -site retention (underground) is recommended within the Golf Villas development
area in order to satisfy City of La Quinta standards for drainage design during the 100
year storm event. The location; layout and relatively small size of the proposed Golf
' Villas development area make underground storm water retention an attractive option.
330NflZi NIVZV10N U,LIS-330 '
■
' OFF -SITE MOUNTAIN RUNOFF
The Specific Plan Amendment boundary (SPA No. 6, Planning Area 1) considered in this
report lies immediately downstream of the existing Santa Rosa Cove community and an
adjacent mountain range immediately to the north and west. The mountain range -
watershed is shown on the Watershed Exhibit included in the Appendix of this report.
An existing golf course which forms a portion of the existing La 'nta Resort and
Oleander C anne s collects e ma�onty o wa ers a at the base of the ounta'
where it becomes =part the Whitewater River W�The small percentage of
untainru e lately directentgurse drain age channel is
' collected by various drainage facilities and surface streets upstream of the Specific Plan
Amendment boundary.
rSeveral nvestigations of the project area and data available from the existing Spe
eport prepared by MDS Consulting, Inc. in 1998 confirm that any remaining he mountain watershed reaching Calle Mazatlan and Avenida Fernando, tream edge of the project does not encroach into the Specific Plan
boundary. „
?t:> p r�
e � %.4 I
l
� MS -4 PERMIT
1
1
1
1
1
1
1
1
1
1
1
1'
J
'1
t
in
I-
1 V \ l7 0
tThe MS4 Permit
n�7/
On arch 9, 2006 he County of Riverside and the Riverside County Flood Control and
Water rvation District (hereafter referred to as permittees) in cooperation with the
Coachella Valley Water District and other cities (hereafter referred to as co- permittees,
submitted NPDES Application No. CAS617002 for reissuance of the MS4 NPDES
Permit for the Whitewater River Basin. In response to the submittal, The California
Regional Water Quality Control Board, Colorado River Basin Region, adopted Order No.
' R7- 2008 -0001 on May 21, 2008, which renews the permit until May 21, 2013.
As a co- permittee, the City of La Quinta is responsible for operation of the MS4 storm
facilities within the City limits and the discharge of urban runoff into these facilities. In
La Quinta, the MS4 facilities consist primarily of the La Quinta Resort Channel, the La
Quinta Evacuation Channel and the Whitewater River. The two channels are tributary to
' the Whitewater River'and Coachella Valley Storm Channel (i.e., receiving waters) which
drain ultimately to the Salton Sea.
All development/redevelopment at the La Quinta Resort must comply with these MS -4
permit requirements as the on -site storm drain facilities drain to the adjacent golf course
within the Oleander and La Quinta Resort Channels, part of the Whitewater River
Watershed. As a co- permittee, the City of La Quinta is responsible for ensuring
compliance with this permit including the mitigation and monitoring of urban runoff to
these facilities.
' Water Quality Management Plan (WQMP)
l
1
For proposed redevelopment at the Resort, a Water Quality Management Plan (WQMP)
must be prepared and implemented. This plan will identify best management practices
(BMP's) required by the project to meet the MS -4 permit requirements, and the BMP's
will be identified on final construction documents. Once constructed, the
developer /owner will be responsible for the ongoing implementation of the plan over the
life of the project.
At the Site Development phase, the following pre- development information and best
management practices (BMP's) will be confirmed:
Project Site Address:
PA/Community Name:
Thomas Bros. Map:
Project Watershed:
The project is located at the west of Eisenhower and south
of Avenida Fernando, in the City of La Quinta, County of
Riverside, California.
La Quinta Resort and Club
Riverside Co. Pg. 849 Sec E -5 and E -6, 2006 Edition
Whitewater River
0'v
Sub- watershed: La Quinta Resort Channel/La Quinta Evacuation Channel
Standard Industrial Classification (SIC) Code: 1521 and 1522
Pervious/Impervious Areas: In general, the existing and proposed land uses (and
pervious /impervious ratios) remain the same.
Formation of Home Owners' Association (HOA) or Property Owners Association (POA):
Yes; Association and resort ownership will ensure that appropriate staff has training,
education and documentation to maintain the BMP's as proposed.
Additional Permits /Annrovals required for the Proiect:
Agency
Permit required (yes or no)
State Department of Fish and Game, 1601 Streambed
Alteration Agreement
No
State Water Resources Control Board, Clean Water
Act (CWA) section 401 Water Quality Certification
No
US Army Corps of Engineers, CWA section 404
permit
No
US Fish and Wildlife, Endangered Species Act section
7 biological opinion
No 1
SWRCB General Construction Permit
Yes
City of La Quinta Building Permit
Yes
City of La Quinta Grading Permit
Yes
Land Use Designation or Zoning: CT Tourist Commercial, Medium Density
Residential
Current Property Use: Residential, Hotel, Conference Center, Retail, Restaurant
Proposed Property Use: t same
Availability of Soils Report: Yes
Phase 1 Site Assessment: Yes
v
Receiving Waters for Urban Runoff from Site
Receiving Waters
303(d) List Impairments
Designated Beneficial
Proximity to RARE
Uses
Beneficial Use
La Quinta Resort
None
FRSH, GWR, REC 2,
Not Designated as
Channel
WILD
RARE (0.5 miles)
La Quinta
None
FRSH, GWR, REC 2,
Not Designated as
Evacuation Channel
WILD
RARE (1.5 miles)
None
MUN, AGR, GWR,
Not Designated as
Whitewater River
REC 1, REC 2, WARM,
RARE (4.0 miles)
COLD, WILD, POW
Coachella Valley
Pathogens, Toxaphene
FRSH, REC 1, REC 2,
Designated as
Storm Drain
WARM, WILD, RARE
RARE (10.5 miles)
Nutrients, Salinity,
AQUA, IND, REC 1,
Designated 'as
Salton Sea
Selenium i
REC 2, WARM, WILD;
RARE
RARE (27.5 miles)
Potential Project Pollutants/Pollutants of Concern (based on land use):
■ Pathogens, Metals, Nutrients (pollutant of concern), Pesticides, Organic
Compounds, Sediments, Trash & Debris, Oxygen- Demanding Substances, Oil
& Grease.
Pollutants Impairing Proximate Receiving Waters:
■ Salton Sea - Impaired by Nutrients, Salinity and Selenium.
Legacy Pollutants:
■ The project site is currently developed. There are no known activities
associated with legacy pollutants or pesticides that have taken place on this
property in the past.
Treatment Control BMP Recommendations:
In general, Stantec recommends on -site retention/infiltration throughout the Resort in
accordance with Sections F.l.c.v.4 and F.l.c.v.5 of the MS4 Permit. Note that the
storm flows associated with the Morgan House, Grove Condos and Wellness Center
will be captured by the adjacent existing storm drain, which drains ultimately to the
resort golf course. BMP's such as water quality inlets, sand filters and porous
pavement may be utilized to treat potential pollutants from these areas. Extended
detention facilities and/or modification of the existing golf course lake(s) within the
golf course may be also utilized.
FA
4 -•
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
APPENDIX "A"
REFERENCE MATERIAL
so
0
Pr tatioorequenc Da "erveMP M M M M M ORge Fl M
" POINT PRECIPITATION`
. FREQUENCY ESTIMATES �_ _ j
FROM NOAA ATLAS 14
California 33.69005 N 116.31487 W 183 feet
from "Precipitation- Frequency Atlas of the United States" NOAA Atlas 14, Volume 1, Version 4
G.M. Bonin, D. Martin, B. Lin, T. Paraybok, M.Yekta, and D. Riley
NOAA,' National Weather Service, Silver Spring, Maryland, 2006
Extracted: Thu Mar 5 2009
.,.,.. r
i'Confide�ce Limlts "�Seasonatlty Location Maps { ' Other Infot ,` GiS data 'Maps Docs
Precinitation Freauencv Estimates (inches)
ARI*
(years)
5
min
10
min
15
min
30
min
60
I min
120
3 hr
6 hr
12
hr
24
hr
48
hr
4
d�a
7
day
10
20
dad±
30
day
45
day
60
day
min
2.60
2.87
' These precipitation frequency estimates are based on a partial duration series. ARI is the Average Recurrence Interval.
Please refer to NOAA Atlas 14 Document for more information. NOTE: Formatting forces estimates near zero to appear as zero.
* Upper bound of the 90% confidence interval
Precipitation Frequency Estimates (inches)
ARI 5 X1' Ml� 30 60 120 3 6 12 24 48 4 7 30 (years) min � min min hr hr hr hr hr day day day day day day day
1� 0.13
Efl 0.25 0.34 0.41 0.56 0.64 0.85 1.04 1.10 1.10 1.18 1.29 1.37 1.54 1.72 1.93 2.05
�� 0�1� 0�2� 0 35 o� o� o� 7� o�� 1 14 1�41� 1 0 11 52� 1 60 1�5 1 86 2 1 2 6 2 66 2 82
C�
0.29 0.44 0.55
0.73
0.91 1.17
1.30 1.69 2.08
T 27EflEfl
2.60
2.78
3.17 3.55 3.99
4.25
10
0.38
0.58
0.72
0.97
1.20
1.52
1.68
2.13
2.60
2.87
2.89
3.03
3.27
3.52
3.99 4.46 5.00
5.32
25 0.53 110 .81 1 00]LL5jj1 .67 112 .06 2.24 2.79 3.34 L:L_2jL.L6jj3 .98 114 .25 114 .57 115 .16 115 .74 116 .39 6.84
Retum to "State Map ft
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DURAT IUM:
stifitilk
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4S Contours
gX-1 A10,
Elevation:'
WROM'Pt' )N
ta
6V---.960=
116 360
,136 54 0
X1541 A
0
Via_: j 2000
—",lT4V '
i
4WEV and V4WHV
Eta.
i'rHE 4WHV AND V4WHV SERIES NON -CLOG PUMPS
L ARE DESIGNED PRIMARILY FOR COMMERCIAL
APPLICATIONS SUCH AS: schools and churches, industrial
plants, shopping centers, apartments and condominiums,
marinas, interstate rest stops, sewage collection systems,
campgrounds, motels, restaurants, office and commercial
buildings, state and federal parks, hospitals and nursing
homes, dewatering, trailer parks and treatment plants.
This pump can be installed on legs (vertical discharge)
or with a quick- disconnect slide rail system. Its ability to
handle 3 -inch spherical solids makes it ideal for most
light to medium commercial installations. For more
information, contact your Myers distributor, or the Myers
Ohio sales office at 419/289 -1144.
ISO snni
4" Non -Clog Wastewater Pumps
Horizontal and Vertical Discharge
ADS A"NTAGES BY DESIGN
HIGH EFFICIENCY HYDRAULIC DESIGN CUTS
PUMPING COSTS AND EXTENDS LIFE OF FLUID
END COMPONENTS.
• Two -vane rounded port impellers handle
solids with ease at high operating efficiencies.
• Modified constant velocity volute offers quiet
operation, low radial loads over extended
portion of performance curve.
DURABLE MOTOR WILL PROVIDE MANY YEARS
OF RELIABLE SERVICE.
• Oil- filled for maximum heat dissipation and
continuous bearing lubrication.
• Heat sensor thermostats imbedded in windings
protect motor from overheat conditions.
• Seal leak probe in seal chamber warns of
moisture entry, helps prevent costly motor
bum -out.
PRODUCT CAPABILITIES
Capacities To 720 gpm
45.51ps
Heads To 59 it 17.9 m
Solids Handling Capacity (dia.) 3 in. 76 mm
Liquids Handling raw, unscreened sewage,
rain water, effluent
Intermittent Liquid Temp. 140'F j 60-C
Winding Insulation Temp. 266'F 130'C
(Class B) '
Available Motors 1750 rpm:
(Single phase motors are capacitor start- 3 -5 HP, 230V, 10. 60 Hz
arrequird or proper 3 -10 HP, 200/230/460/575V,
tis ereeltpopreatlr
and warranty.) 30,60 Hz
Third Party Approval CSA ETL
Acceptable pH Range 6 -9
Specific Gravity .9 -1.1
Viscosity 28 -35 SSU
Discharge. Flanged Centerline 4 in.
101.6 mm
(Horizontal or Vertical)
Fasteners
Minimum Sump Dia. (Duplex) 60 in.
1.5 m
Note: Consult factory for applications outside of these
recommendations.
Construction Materials
Motor Housing, Seal
cast iron, class 30
Housing. Cord Cap.
ASTM A48 -76
Volute Case
Enclosed 2 -Vane Impeller
ductile iron, class 65
ASTM A536 -80
Power, Conlrol.Cords
SOW /SOWA. 20 It.
Mechanical Seals
double tandem. type 21
standard - carbon /ceramic
optional - tungsten carbide
Pump. Motor Shalt
416 SST
Fasteners
300 series SST
Wear Ring
brass
WHERE INNOVA9TON MEETS TRADTITON
4WHV and V4WHV
r Non -Clog Wastewater Pumps
' Horizontal and Vertical Discharge
■
■
RUBBER BUSHING CORD GRIP
Clamp type to prevent
loosening, withstand pull
of 300 pounds.
'
HEAT SENSORS ON MOTOR WINDING
-
Automatically stops motor it winding
Prevents rust build -up and
'
temperature reaches 110 °C. Winding
restore original running
insulation.is class B.
'
efficiencies.
MOTOR STATOR
Shrunk in shell for best
alignment and heat transfer.
/
Oil - tilled for continuous
,
lubrication of bearings and
seals.
'
HEAVY STAINLESS STEEL
SHAFT
Prevents deflection from
'
Impeller radial loads when
pump operates at heads
- higher than peak efficiency
range.
'
TANDEM SHAFT
SEOALL S
i Protect motor, operate in
clean oil.
SEAL LEAH PROBE
Detects water in seal housing,
'
activates red light at control
!
panel. ,—.,
HORIZONTAL
DISCHARGE
VOLUTE CASE
4" flanged.
PUMP OUT VANES
Help keep trash
�; • from seal, reduce
pressure at seal
faces.
HIGH EFFICIENCY "
IMPELLER
Two-vane rounded port,
non - clogging design.
r \,
1
VERTICAL DISCHARGE VOLUTE CASE
Includes support legs. 4" flanged.
' K3240 3/01
Merw
DIMENSIONS
-Cb
a�1 1av,
PERFORMANCE CURVE
CAPACITY • LITERS PER MINUTE
Soo 1000 1500 2000
60
50
a
30
0
~ 21
2500
0 100 200 300 400 500 600 700
CAPACITY - GPM
B
e
4a
x �
10 4
6
e
x
F. E. Myers, 1101 Myers Parkway, Ashland, Ohio 44805 -1969
419/289 -1144, FAX: 419 /289 -6658, www.temyers.com
Myers (Canada). 269Trillium Drive. Kitrhannr (lntnrin N9n ews
BRASS WEAR RING
Prevents rust build -up and
'
reduces leakage and
wear. Replaceable to
restore original running
clearances and pump
efficiencies.
HORIZONTAL
DISCHARGE
VOLUTE CASE
4" flanged.
PUMP OUT VANES
Help keep trash
�; • from seal, reduce
pressure at seal
faces.
HIGH EFFICIENCY "
IMPELLER
Two-vane rounded port,
non - clogging design.
r \,
1
VERTICAL DISCHARGE VOLUTE CASE
Includes support legs. 4" flanged.
' K3240 3/01
Merw
DIMENSIONS
-Cb
a�1 1av,
PERFORMANCE CURVE
CAPACITY • LITERS PER MINUTE
Soo 1000 1500 2000
60
50
a
30
0
~ 21
2500
0 100 200 300 400 500 600 700
CAPACITY - GPM
B
e
4a
x �
10 4
6
e
x
F. E. Myers, 1101 Myers Parkway, Ashland, Ohio 44805 -1969
419/289 -1144, FAX: 419 /289 -6658, www.temyers.com
Myers (Canada). 269Trillium Drive. Kitrhannr (lntnrin N9n ews
a
Pump Performance
Pump performance is based on clear water (1.0 specific gravity 0 68 °F) and pump fluid and (hydraulic) efficiency. Motor data based on 40 °C ambient temperature.
Available Models
Motor Electrical Date
Service
Service
NEC
Start
Run
Factor
Run
Factor
Start
Run
Code
Service
Standard
HP
Volts
Phase
Hertz
Amos
Amos
Amos
KW
KW
KVA
KVA
Letter
Factor
4WHV301M4 -21
3
230
1
60
101
17.5
21
2.1
2.5
23.2
4.0
J
1.2
4WHV30M4 -03
3
200
3
60
66.7
15
18
3.5
4.3
23.0
5.0
G
1.2
4WHV30M4 -23
3
230
3
60
58
12
14.4
3.5
4.3
23.0
5.0
G
1.2
4WHV30M4 -43
3
460
3
60
29
6
7.2
3.5
4.3
23.0
5.0
G
1.2
4WHV30M4 -53
3
575
3
60
21.3
5
6
3.5
4.3
23.0
5.0 1
G
1.2
4WHV50M4 -21
5
230
1
60
141
34
41
6.3
7.7
32.4
7.8
H
1.2
4WHV50M4 -03
5
200
3
60
111
21.6
26
5.6
6.9
38.4
7.2
H
1.2
4WHV50M4.23
5
230
3
60
96
18
21.6
5.6
6.9
38.4
7.2
H .
1.2
4WHV50M4 -43
5
460
3
60
48
9
10.8
5.6
6.9
38.4
I
7.2
H
1.2
I
4WHV50M4 -53
5
575
3
60
39
7.2
8.6
5.6
6.9
38.4
7.2
H
1.2
4WHV75M4 -03
7.5
200
3
60
172
32.2
37
8.0
9.9
59.5
11.1
J
1.2
4WHV75M4 -23
7.5
230
3
60
150
28
32
8.0
9.9
59.7
11.1
J
1.2
4WHV75M4.43
7.5
460
3
60
74.8
14
16
8.0
9.9
59.7
11.1
J
1.2
4WHV75M4 -53
7.5
575
3
60
67.2
11.2
13
8.0
9.9
66.8
11.1
K
1.2
4WHV100M4 -03
10
200
3
60
172
37
37
10.1
10.1
59.5
12.8
G
I 1.0
4WHV100M4 -23
10
230
3
60
150
32
32
10.1
10.1
59.7
12.8
G
I 1.0
4WHV100144 -43
10
460
3
60
74.6
16
16
10.1
10.1
59.7
12.8
G
I 1.0
4WHV100M4 -53
10
575
3
60
67.2
13
13
10.1
10.1
66.8
12.8
H
i 10
® F. E, Myers, 1101 Myers Parkway, Ashland, Ohio 44805 -1969
1(3613 6/98 4191289 -1144 • FAX:4191289 -6658 • www.temyers.com
Printed in U.S.A.
f
r
APPENDIX "B"
HYDROLOGY .MAPS
�f 1
received,
MAR 111 2009
City of La 6luinto
Plonning Deportment
GEOTECHNICAL INVESTIGATION
PROPOSED RESORT EXPANSIONIRENOVATION
LA QCilNTA RESORT & CLUB
49-499 EISENHOWER DRIVE
LA QUINTA. CALIFORNIA
a -
n
-Prepared By-
Sladden Engineering
77-725 Enfield Lane, Suite 100
Palm Desert, California 92211 .
(760) 772.3893
Sladden Engineering
r.
Sladden Engineering
77 -725 Enfield Lane, Suite 100, Palm Desert, CA 92211 (760) 772 -3893 Fax (760) 772 -3895
6782 Stanton Avenue. Suite A. Buena Park, CA 90621 (714) 523 -0952 Fax (714) 523 -1369
450 Egan Avenue. Beaumont, CA 92223 (951) 845 -7743 Fax (951) 845 -8863
January 7, 2009 Project No. 544 -08277
08 -12 -650
Pyramid Project Management LLC
c/o Stantec
73733 Fred Waring Drive, Suite 100
Palm Desert, CA 92260 -2590
Subject: CeotechnicalInvestigation
Project: Proposed Expansion / Renovation
La Quinta Resort & Club
49 -499 Eisenhower Drive
La Quinta, California
Sladden Engineering is pleased to present the results of our geotechnical investigation for the
expansion /renovation proposed for the existing I.a Quinta Resort and Club located at 49-499 Eisenhower
Drive in the City of La Quinta, California. Our services were completed in accordance with our proposal
for geoteehnical engineering services October 17, 200$, and your authorization to proceed with the work.
The purpose of our investigation was to explore the subsurface conditions at the site in order to provide
preliminary recommendations for foundation design and site preparation. Evaluation of environmental
issues and hazardous wastes was not included within the scope of services provided.
The opinions, recommendations and design criteria presented in this report are based on our field
exploration program, laboratory testing and engineering analyses. Based on the results of our
investigation, it is out professional opinion that the proposed project is feasible, provided the
recommendations presented in this report are implemented in the project and construction.
We appreciate the opportunity to provide service to you on this project. If you have any questions
regarding this report, please contact the undersigned.
respectfully submitted,
SLADDEN ENGINEERING
Matthew J. Cohrt
Project Geologist
SER/mc
Copies: 6 /Addressee
Principal Engineer
Sladden Engineering
" RESORT EXPANSION/RENOVATION
. - LA Ql}DNIA RESORT &CLUB
'
49'499 EISENHOWER IIRVE
~ � LA QU7NTA.KALTFORVJA �
. January },2009
`
� TABLE OF CONTENT'S .
` INTRODUC71ON ............................... ............ .................................. l
.^1"RQlGC7 DESCRIPTION --'--'....------_----_—_----------------'1
SCOPE OF SERVICES .......................................................................................... .................................. 2
SITE --.._---.'^...--.--.~~------.''2
GEOLOGICSE7-F{�� ............................................................................................................................. 3
SUBSURFACE CONDITIONS ................................................................................................................. 3 .
SEISMICITYAND FAULTING ....................................... ...................................................................... 4
CBC DESIGN PARAMETERS ..................... ......................................................................................... 9
GEOLOGICHAZARDS .................................................................................................... ....................... 5
�Seismic Hazards ..................................................................... ........................................................... 5. �
.Non-Seismic Hazards ...................................... _—._—_----._._---''_------'6 '
�
� CONCLUSIONS ------'---_--_---__.--------_---_'--.—..—.7
� - ��RTBlVOV�K AND G8Al�I�JG-----_---'—_—_'—'''__—'''_'_----�
*
�
Stripping--------------------.^..—.......—.--.--''-------.
.
8 .
Preparationof Building Areas ............................................................................................... .........
0
Compaction —.~...........................---------_---------__--..0
� Shrinkage and Subsidence .................................................... .......... .... .........................................
9
FOUNDATIONS | � SPREAD FOOTINGS .............................................................. .................................
9 �
---._-------_—_'_____—~,...,...~.--.---'---'-10
' -
� RETAINING WALLS ......................................................................... _----------_...........
l0
| 'SOLUBLE SULFATES ....................................................................................... -----__--_-ll
' `
� \ - UTILITY TRENCH BACKFlLL ..............................................................................................................
11 '
EXTERIOR CONCRGTEEpLa?vVORK .................................................................................................
Il
DRAINAGE ........................ ... .................................................................. ........................................... �-.-ll
` LIMITATIONS ....................................... .................................................................................................
I2 '
ADDITIONAL SERVICES ............................................. ------------- ................ ...............
12
REFERENCES..........................................................................................................................................
. .
13.
FIGURES Site Location Map. �
Regional Geologic Map
Borehole Location Plan
Subsidence Zones Map�
. APPENDIX A' Field Exploration _
APPENDIX B- Laboratory Tmodnx
APPENDIX C- Retaining Walls-Seismic Conditions
�
_
� '
_ Sladden Engineering
. '
` i
January 7, 2009 - 1 - Project No. 544 -08277
08-12 -650
INTRODUCTION
This report presents the results of the geotechnical investigation performed by Sladden Engineering
(Sladden) for the proposed expansion and renovation of the La Quinta Resort and Club located at 49 -499
Eisenhower Drive in the City of La Quinta, California. The site is located on the south Y2 of Section 36,
Township 5 South, Range 6 East (SBBM) at approximately 33.6887 north latitude and 116.3104 west
longitude. The approximate location of the site is indicated on the Site Location Map (Figure 1).
Our investigation was conducted in order to evaluate the engineering properties of the subsurface
materials, to evaluate their in -situ characteristics and to provide preliminary engineering
recommendations and design criteria for site preparation, foundation design and the design of various.
site improvements. This study also includes a review of published and unpublished geotechnical and
geological literature regarding seismicity at and near the subject site.
PROJECT DESCRIPTION
Based on our preliminary conversations, it is our understanding that the proposed project will consist of
demolishing several existing structures on -site and constructing several new structures. In addition, the
project is anticipated to include the renovation of the existing clubhouse. The proposed expansion will
include multi -story structures with bi -level subterranean parking. The project is also anticipated to
include, new concrete flatwork and various other improvements. For our analyses we expect that the
proposed project will consist of a relatively lightweight wood - framed, steel framed and reinforced
masonry structures supported on conventional shallow spread fdotings and concrete slabs -on- grade. The
subterranean levels are expected to be of reinforced masonry or cast -in -place reinforced concrete
construction.
The project was in the preliminary design stages at the time of this report. Therefore, grading plans and
finished floor elevations were not available. Accordingly, the amount of grading to be performed remains
unknown at this time. However, based on the proposed subterranean parking levels and the elevations of
the existing structures, Sladden anticipates that significant excavation and some near surface grading will
be required in order to accomplish the desired elevations. This does not include the removal and
recompaction of foundation bearing soil within the building areas. Upon completion of project plans, we
should be consulted in order to confirm that the recommendations presented within in this report are
incorporated into the design of the proposed project_
Structural foundation loads were not available at the time of this report. Based on our experience with
relatively lightweight structures, we expect that isolated column loads will be less than 50 kips and
continuous wall loads will be less than 5.0 kips per linear foot for the lightweight above grade structures.
Isolated column loads of up to 300 kips and continuous wall loads of up to 10 kips /foot are expected 'in
the subterranean parking levels. If these assumed loads vary significantly from the actual loads we
should be consulted to verify the applicability of the recommendations provided.
Sladden Engineering
January 7, 2009 - 2 - Project No. 544 - 081277
08 -12 -650
SCOPE OF SERVICES
The purpose of our investigation was to determine specific engineering characteristics of the surface and
near surface soil in order to develop foundation design criteria and recommendations for site
preparation. Exploration of the site was achieved by advancing six (6) exploratory boreholes to depths
between approximately 215 and 61.5 feet below. (existing) ground surface (bgs). Specifically, our site
characterization consisted of the following tasks:
• Site reconnaissance to assess the existing surface. conditions on and adjacent to the site.
• The excavation of six (6) exploratory boreholes to depths between approximately 21.5 and 61.5 feet in
order to characterize the subsurface conditions. Representative samples of the soil was classified in
the field and retained for laboratory testing and engineering analyses..
The performance of laboratory testing on select samples to evaluate their engineering characteristics.
• The review of geologic literature and discussions of geologic hazards.
• The performance of engineering analyses to develop recommendations for foundation design and site
preparation.
The preparation of this report summarizing our work at the site.
SITE CONDITIONS
T'he site is situated within La Quinta Resort at 49-499 Eisenhower Drive in the City of La Quinta,
California. The site is occupied by existing hotel structures, auxiliary structures, restaurants, shopping
areas and various other resort related improvements. According to the USGS (1980), site is at an
approximate elevation of 40 to 50 feet above mean sea level (AMSL).
No natural ponding of water or surface seepage was observed at or near the site during our investigation
conducted on December 19, 2008. Site drainage appears to be controlled via sheet flow gradients and
surface infiltration.
Sladden Engineering .
January 7, 2009 - 3 - Project No. 544 -08277
08 -12 -650
GEOLOGIC SETTING
The project site is located within the Colorado Desert Physiographic Province (also referred to as the
Salton Trough) that is characterized as a northwest - southeast trending structural depression extending
from the Gulf of California to the Banning Pass. The Salton Trough is dominated by several northwest
trending faults, most notably the San Andreas Fault system. The Salton Trough is bounded by the Santa
Rosa — San Jacinto Mountains on the southwest, the San Bernardino Mountains on the north, the Little
San Bernardino - Chocolate — Orocopia Mountains on the cast, and extends through the imperial Valley
into the Gulf of California on the south.
A relatively thick sequence (20,000 feet) of sediment has been deposited in the Coachella Valley portion of
the Salton Trough from Miocene to present times. These sediments are predominately terrestrial in nature
with some lacustrian (lake) and minor marine deposits. The major contributor of these sediments has-
been the Colorado River. The mountains surrounding the Coachella Valley are composed primarily of
'Precambrian metamorphic and Mesozoic "granitic" rock.
The Salton Trough is an internally draining area with no readily available outlet to Gulf of California and
with portions well below sea level ( -253' msl). The region is intermittently blocked from the Gulf of
California by the damming effects of the Colorado River delta (current elevation +30'msl). Between about
300AD and 1600 AD (to 1700 ?) the Salton.Trough has been inundated by the Rivers water, forming
ancient bake Cahuilla (max. elevation +58' msl). Since that time the floor of the Trough has been
repeatedly flooded with other "fresh" water lakes (1849, 7.861., and 1891), the most recent and historically
long lived being the current Salton Sea (1905). The sole outlet for these waters is evaporation, leaving
behind vast amounts of terrestrial sediment materials and evaporate minerals.
The site vicituty has been mapped by Rogers (1965) to be immediately underlain by Quaternary-age
undifferentiated alluvium (Qal) and lacustrine deposits (Ql). The regional geologic setting for the site and
site vicinity is presented on the Regional Geologic Map (Figure 2).
SUBSURFACE CONDITIONS
The subsurface conditions at the site were investigated by drilling six (6) exploratory boreholes. The
approximate locations of the boreholes are illustrated on the Borehole Location Photograph (Figure 3).
The be >rehvlus were ajvancctid using a truck - mounted drill -.r.is (Mobil B -61) equipped with 8 -inch outside
diameter. (O.D.) hollow -stem flight augers. A representative of Sladden was on -site to log the materials
encountered and retrieve samples for laboratory testing and engineering analysis.
During our field investigation, fill soil (overlain by asphaltic concrete sections) were encountered directly
overlying native earth materials consisting of alluvium and lacustrine (lake) deposits. Site fill soil was
encountered to a maximum depth of approximately 2 to 4 feet and generally consists of silty sand (SM)
and sandy- to clayey -silt (ML). The fill materials appeared very loose to loose, moist, fine - grained and
exhibited a yellowish brown in -situ color. The underlying alluvium and lacustrine deposits consist of
silty sand (SM) and sandy- to clayey -silt (ML) interbeds /laminations that were encountered to the
maximum depths explored. The alluvium appeared dry to moist, loose to medium dense, fine - grained
and locally micaceous. 'Lacustrine sediments appeared moist, stiff, locally micaceous and exhibited
characteristics indicative to low to medium plasticity soil. Bedrock: was not encountered to the depths
explored for this investigation. Detailed descriptions of the subsurface materials encountered are
included in Appendix A of this report.
Sladden Engineering
January 7, 2009 - 4 - Project No. 544 -08277
08 -12 -650
Groundwater was not encountered. during our investigation on December 19, 2008. Based upon our
review of CVCWD (1975) and Tyley (1974) and our experience with similar projects in the :area, it is our
professional opinion that groundwater should not be encountered during the construction of the
proposed project. However, following periods of heavy or prolonged rainfall, perched groundwater or
seepage may be encountered within deeper excavatiosn, However, we expect that the flow would be
minimal and would dissipate rapidly. 1
SEISMICITY AND FAULTING
The southwestern United States is a tectonically active and structurally complex region, dominated by
northwest trending dextral faults. Faults in the region are often part of complex fault systems composed
of numerous subparallel faults that splay or step from main fault traces. Strong seismic shaking could be
produced by any of these faults during the design life of the proposed project.
Sladden considers the most significant geologic hazard to the project to be the potential for moderate to
severe ground motion that is likely to occur during the design life of the project. The proposed project is
located in the highly seismic Southern California region within the influence of several fault systems that
are considered to be active or potentially active. An active fault is defined by the State of California as a
"sufficiently active and well defined fault" that has exhibited surface displacement within the Holocene
epoch (about the last 11,000 years). A potentially active fault is defined by the State as a fault with a
history of movement within Pleistocene time (between 11,000 and 1.6 million years ago).
Based on our research, the site is not currently located within any State of California designated fault
zone (Hart and Bryant 1997). Table 1 lists the closest known potentially active faults that was generated,
in part, using; the EQFAULT computer program (Blake, 2000) and regional geologic maps (Rogers, 1965),
as modified using the fault parameters from The Revised 2002 California Probabilistic Seismic Hazard
Maps (Cao et al, 2003). This table does not identify the probability of reactivation or the on -site effects
from earthquakes occurring on any of the other faults in the region.
TABLE
CLOSEST KNOWN ACTIVE FAULTS
Fault Name
Distance
Km
Maximum
Event
San Andreas - Coachella
12.1
7.2
San Andreas - Southern
12.1'
7.2
13umt Mountain
29.2
6.5
San Andreas - San Bernardino
30.3
7.5
Eureka Peak
31.1
6.4
San Jacinto - Anza
31.1
7.2
San Jacinto - Coyote Creek
31.6
6.8
Sladden Engineering
January 7, 2009 - 5 - Project No. 544 -08277
08- 12-650
2007 CBC SEISMIC DESIGN PARAMETERS
Sladden has reviewed the 2007 California Building Code (CBC) and summarized the current seismic
design parameters for the proposed project. 'rhe seismic design category for a structure may be
determined in accordance with Section 1613 of the 2007 CBC or ASCE7. According to the 2007 CBC, Site
Class D may be used to estimate design seismic loading for the proposed structure.. The period of the
structure should be less than Sh second. This assumption should be verified by the project structural
engineer. The 2007 C13C Seismic Design Parameters are summarized below.
Occupancy Category (Table 1604.5):11
Site Class (Table 1613.5.5): 1)
Ss (Figure 1613.5.1):1.500g
S1(Figure 161.3.5.1): 0.600g
Fa (fable 1613.5.3(1)):1.0
Fv (Table 1613.5.3(2)):1.5
Sms (Equation 1.6 -37 (Fa X Ss)) : 1.500g
Smi (Equation 16-38 {Fv X Si)): 0.9008
Sys (Equation 16-39 (2/3 X Sms)): 1.0008
SD1 (Equation 1.6 -4.0 (2/3 X Sm1)): 0.600g
Seismic Design Category: D
GEOLOGIC HAZARDS
The subject site is located in an active seismic zone and will likely experience strong seismic shaking
during the design life of the proposed project. In general, the intensity of ground shaking will depend on
several factors including: the distance to the earthquake focus, the earthquake magnitude, the response
characteristics of the underlying earth inaterials, and the quality and type of construction. Geologic
hazards and their relationship to the site are discussed below.
A. Seismic Hazards
1. Surface Rupture. Surface rupture is expected to occur along preexisting, known active fault
"traces. However, surface rupture could potentially splay or step from known active faults
or rupture along unidentified traces. Based on our review of Rogers (1965), Jennings (1994),
RCLIS (2009) and Hart and Bryant (1997) no known faults are currently mapped on or
projecting immediately adjacent to the site. No signs of fault rupture or secondary seismic
effects (lateral spreading, lurching etc.) were identified on -site during our field
investigation. Therefore, it is our opinion that risks associated with primary surface ground
rupture should be considered "low".
I.I.. round Shaking. The site has been subjected to past ground shaking by both local and
regional faults that traverse through the region. Seismic shaking from nearby active faults
is expected to produce high ground accelerations during the design life of the proposed
project.
A probabilistic approach was employed to the estimate the peak. ground acceleration (a..)
that could be experienced at the site- Based on the USGS Probabilistic Hazard Curves
(USGS, 2008) the site could be subjected to ground accelerations on the order of 0.4950g.
Sladden Engineering
January 7, 2009
- 6 - Project No. 544 -08277
08 -12 -650
1be peak ground acceleration at the site is judged to have a 475 year return period and a 10
percent chance of exceedence in 50 years.
III. Liquefaction. Liquefaction is the process in which loose, saturated granular soil loses
strength as a .result of cyclic loading. The strength loss is a result of a decrease in granular
sand volume and a positive increase in pore pressures. During seismic shaking, liquefiable
strata consolidate in response to cyclic loading conditions. Surface manifestations could
potentially include sand boils and settlement. Generally, liquefaction can occur if all of the
following conditions apply: liquefaction - susceptible soil, groundwater_ within a depth of 50
feet or less, and strong seismic shaking.
Based on the depth to groundwater in the site vicinity ( >50 feet) it is our professional' that
risks of liquefaction and liquefaction related hazards at the site should be considered
.,low„
IV. Settlement. Settlement resulting from the anticipated foundation loads should be tolerable
provided that the recommendations included in this report are considered in foundation
design and construction. The estimated ultimate settlement is calculated to be less than one
inch when using the recommended bearing values. As a practical matter, differential
settlement between footings can be assumed as one -half of the total settlement for similarly
loaded footings spaced up to 40 feet apart.
V, Tsunamis and Seiches. Because the site is situated at an inland elevated location and not
immediately adjacent to any impounded bodies of water, risks associated with tsunamis
and seiches are considered negligible.
B. Non - Seismic Ha7,ards
I. Slope Failure, Landsliding, Rock Falls. No signs of slope instability in the form of
landslides, rock falls, slumps or earthflows were observed on or immediately adjacent to
the site. According, risks associated with slope instability are considered "negligible'.
II. Expansive Soil. Expansion Index testing of select samples was performed in order to
evaluate expansive potential of the materials underlying the site. Based the results of our
laboratory testing (U3 2), the materials underlying the site are considered "non- expansive"
Accordingly, risk of structural damage caused by volumetric changes in the subgrade soil
is considered negligible.
Ill. Subsidence. Land subsidence can occur in valleys where aquifer systems have been
subjected to extensive groundwater pumping, such that groundwater pumping exceeds
groundwater recharge. Generally, pore water reduction can result in a rearrangement of
skeletal grains and could result in elastic (recoverable) or inelastic (unrecoverable)
deformation of an aquifer system (USCS, 2001.).
Sneed and Brandt (USGS, 2007) have reported significant land subsidence measurements
within the area of La Quinta as measured between 1996 and 2005. According to the
aforementioned authors, the subject site is part of the broader "La Qhiinta subsidence area ".
This northwest- southeast trending subsidence zone is generally defined .as an elongated
subsidence bowl bounded by the westward extension of Avenue 48 to the north, Avenue
Sadden Engineering
January 7, 20X)9
- 7 - Project No. 544 -08277
08- 12-650
60 to the south, the Santa Rosa Mountains to the west and varying streets from Jefferson
Street to Monroe Street to the Fast (Figure 4). Measurements of the northern portion of this
subsidence zone from May 7, 2003 and September 25, 2005 have indicated subsidence of
0.52 feet.
Although recent investigations have documented significant subsidence within the area of
the proposed project (USGS, 2007), no fissures or other surficial evidence of subsidence
were observed at the subject site. With the exception of isolated tension zones typically
manifested on the ground surface as fissures and /or ground cracks, subsidence related to
groundwater depletion is generally areal in nature with very little differential settlement
over short distances such as across individual buildings.
The Coachella Valley Water District has publically acknowledged regional subsidence
throughout the southern portion of the Coachella Valley and has indicated a commitment
to groundwater replenishment programs that are intended to limit future subsidence. At
this time, subsidence is considered a regional problem requiring regional mitigation not
specific to the project vicinity.
IV. Flooding and Erosion. No signs of flooding or erosion were observed during our field
investigation conducted on December 19, 2008. Therefore, risks associated with active
flooding and erosion is considered negligible.
CONCLUSIONS
Based on the results of our investigation, it is our professional opinion that the project is feasible from a
soil mechanic's standpoint provided the recommendations of this report are incorporated in the project
design and carried out through construction. Because of existing undisclosed subsurface improvements
and due to the existing structures currently in conflict with new building areas on -site, Sladden
recommends that additional geotechnical borings and geotechnical analyses be conducted once site
demolition has been accomplished and proposed structure locations are accessible. Additional analyses
will be utilized to ensure that the recommendations contained in this report remain applicable for the
proposed project. Currently, the main geotechnical concern in the construction of the proposed project is
the presence of loose and potentially compressible surface and near surface soil.
The near surface soil on -site is considered loose and potentially compressible and is not suitable for
foundation support in its existing condition. Therefore, grading including the removal and recompaction
the bearing soil is recommended. Specific recommendations for site preparation are presented in the
Earthwork and Crading section of this report.
Caving did occur to varying degrees within each of our exploratory bores and the surface soil may be
susceptible to caving within deeper excavations. All excavations should be constructed in accordance
with the normal CaIOSHA excavation criteria. On the basis of our observations of the materials
encountered, we anticipate that the subsoil will conform to that described by CalOSHA as Type B or C.
Soil conditions should be verified in the field by a "Competent person" employed by the Contractor..
The following recommendations present more detailed design criteria that have been developed on the
basis of our field and laboratory investigation.
Sladden Engineering
January 7, 2009 - 8 - Project No. 544 -08277
08-12 -650
EARTHWORK AND GRADING
All earthwork including excavation, backfill and preparation of the subgrade soil, should be performed in
accordance with the gcotechnical recommendations presented in this report and portions of the local
regulatory requirements, as applicable. All earthwork should be performed under the observation and
testing of a qualified soil engineer. The following recommendations for the proposed project are based on
observations from the field investigation program, laboratory testing and geotechnical engineering
analysis.
a. Stripping. Areas to be graded should be cleared of any existing structures, underground utilities,
vegetation, associated root systems and debris. All areas scheduled to receive fill should be
cleared of old fills and any irreducible matter. The strippings should be removed off site, or
stockpiled for later use in landscape areas. Voids left by obstructions should be properly
backfilled in accordance with the compaction recommendations of this report.
b. Preparation of the Building Areas, In order to achieve a firm and unyielding Bearing surface, we
recommend overexcavation and recompaction throughout the building pad areas. All native low
density near surface soil should be removed to a depth of approximately 5 feet below existing
grade or 5 feet below the bottom of the footings, whichever is deeper. The surface exposed during
over- excavation should be scarified, moisture conditioned to within two percent of optimum
moisture content, and compacted to at least 90 percent relative compaction prior to fill placement.
Remedial grading should extend laterally a minimum of five feet beyond the building perimeter.
Where existing structures limit lateral removals, shoring will likely be necessary.
Slot -cut excavations may be adequate to accomplish the recommended remedial compaction
where at grade structures are planned. We recommend typical ABC slot -cut grading methods. A
slot -cut width of approximately 8 feet should be adequate for preliminary planning purposes. As
always, the most appropriate slot cut width and sequencing should be determined during
grading dependent upon the conditions encountered. If the previous compaction extended.
beyond the existing building footprints as expected, slot cut removals may not be necessary.
C. Compaction. Soil to be used as engineered fill should be free of organic material, debris, and
other deleterious substances, and should not contain irreducible matter greater than three inches
in maximum dimension_ All fill materials should be placed in thin lifts, not exceeding six inches
in their loose state. If import fill is required, the material should be of a low to non - expansive
nature and should be approved by the soil engineer prior to use. Import fill should meet the
following criteria:
Plastic Index Less than 12
Liquid Limit Less than 35
Percent Soil Passing #200 Sieve Between 15% and 35%
Maximum Aggregate Size 3 inches
The subgrade and all fills should be compacted with acceptable compaction equipment, to at
least 90 percent relative compaction. The bottom of the exposed subgrade should be observed by
a representative of Sladden Engineering prior to fill placement. Compaction testing should be
performed on all lifts in order to verify proper placement of the fill materials. 'fable 2 provides a
summary of the excavation and compaction recommendations.
Sladden Engineering
January 7, 2009 - 9 - Project No. 544 -08277
08 -12 -650
TABLE 2
SUMMARY OF RECOMMENDATIONS
"Remedial Grading
Excavation and /or recompaction within the building
envelope and extending laterally for 5 feet beyond
the building limits and to a minimum of 5 feet
below existing grade or 5 feet below the footings,
whichever is deeper.
Native / Import Engineered Fill
Place in thin lifts not exceeding 6 inches in the loose
state, compact to a minimum of 90 percent relative
compaction.
Asphalt Concrete Sections
Compact the top 12 inches to at least 95 percent
compaction within 2 percent of optimum moisture
content.
*Actual depth may vary and should be determined by a representative of Sladden Engineering in the field
during construction.
e. Shrinkage and Subsidence. Volumetric shrinkage of the material that is excavated and replaced
as controlled compacted fill should be anticipated. We estimate that this shrinkage could vary
from 15 to 25 percent Subsidence of the Surfaces that are scarified and compacted should be
between 1 and 2 tenths of a foot. This will vary depending upon the type of equipment used, the
moisture content of the soil at the time of grading and the actual degree of compaction attained.
FOUNDATION: CONVENTIONAL SPREAD FOOTINGS
Load bearing walls may be supported on continuous spread footings and interior columns may be
supported on isolated pad footings. All footings should be founded upon properly engineered fill and
should have a minimum embedment depth of 7.2 inches measured from the lowest adjacent finished-
grade. Continuous and isolated footings should have a minimum width of 18 inches and 24 inches
respectively. Continuous and isolated footings placed on such materials may be designed using an
allowable (net) bearing pressure of 1800 and 2000 pounds per square foot (psf) respectively. Allowable
increases of 250 psf for each additional 1 foot in width and 250 psf for each additional 6 inches in depth
may be utilized, if desired. The maximum allowable bearing pressure should be 4,000 psf. The maximum
bearing value applies to combined dead and sustained live loads.
The allowable bearing pressure may be increased by one -third when considering transient live loads,
including seismic and wind forces. All footings should be reinforced in accordance with the project
structural engineer's recommendations.
Based on the allowable bearing pressures recommended above, total static settlement of conventional
shallow spread footings is anticipated to be less than one -inch, provided foundation preparation
conforms to the recommendations provided in this report. Differential static settlement is anticipated to
be approximately half the total settlement for similarly loaded footings spaced up to approximately 40
feet apart.
Lateral load resistance for the spread footings will be developed by passive soil pressure against the sides
of the footings below grade and by friction acting at the base of the concrete footings bearing on
compacted fill_ An allowable passive pressure of 250 psf per foot of depth may be used for design
Sladden Engineering
January 7, 2009 - 10 - � Project No. 544 -08277
08 -72 -650
purposes. An allowable coefficient of friction 0.45 may be used for dead and sustained live loads to
compote the frictional resistance of the footing placed directly on compacted fill. Under seismic and wind
loading conditions, the-passive pressure and frictional resistance may be increased by one- third. -
All footing excavations should be observed by a representative of the project geotechnical consultant to
verify adequate embedment depths prior to placement of forms, reinforcement or concrete. The
excavations should be trimmed neat, level and square. All loose, disturbed, sloughed or moisture -
softened soil and /or any construction debris should be removed prior to concrete placement. Excavated
soil generated from footing and /or utility trenches should not be stockpiled within the building envelope
or in areas of exterior concrete flatwork.
SLABS -ON- GRADE
In order to reduce the risk of heave, cracking and settlement, concrete slabs -on -grade must be placed on
properly compacted fill as outlined in the previous sections. The slab subgrades should remain near
optimum moisture content and should not be permitted to dry. Prior to concrete pour, all slab subgrades
should be firm and unyielding. Disturbed soil should be removed and then replaced and'compacted to a
minimum of 90 percent relative compaction.
Slab thickness and reinforcement should be determined by the structural engineer. We recommend a
minimum slab thickness of 5.0 inches. All slab reinforcement should be supported on concrete Chairs to
ensure that reinforcement is placed at slab mid - height.
Slabs with moisture sensitive surfaces should be underlain with a moisture vapor retarder consisting of a
polyvinyl chloride membrane such as 10-mil Visqueen, or equivalent. All laps within the membrane
should be sealed, and at least 2 inches of clean sand should be placed over the membrane to promote
uniform curing of the concrete. To reduce the potential for punctures, the membrane should be placed on
a pad surface that has been graded smooth without any sharp protrusions. If a smooth surface can not be
achieved by grading, consideration should be given to placing a 1 -inch thick leveling course of ,sand
across the pad surface prior to placement of the membrane. .
RETAINING WALLS
Cantilever retaining walls may be designee using "active" pressures. Active pressures may be. estimated
using an equivalent fluid weight of 35 pcf for native backfill soil with level free- draining backfill
conditions. For walls that are restrained, "at rest" pressures should be utilized in design. At rest pressures
may be estimated using an equivalent fluid weight of 55 pcf for native backfill soil with level free -
draining backfill conditions. The recommended lateral pressures should also be applicable for use in the
design of temporary shoring sv'stems, if required.
Seismic Conditions — According to the 2007 CBC, seismic loads must be considered in the design of earth
retaining structures. Seismic pressures for retaining (basement) walls with drained level native backfill
soil are summarized in Appendix C of this report. The estimated "seismic" pressures may be utilized for
the design of earth retaining walls up to 25 feet in height. A detailed summary of our seismic retaining
wall loading calculations is included within Appendix C of this report.
Sladden Engineering
January 7, 2009 - 11 - Project No. 544 -08277
08 -12 -650
SOLUBLE SULFATES
Soluble sulfate concentrations were determined to be low (155 & 580 ppm) during our laboratory testing.
The surface soil is generally considered to have a "low" corrosion potential with respect to concrete. The
use of Type V and /or sulfate resistant mix design should not be nece — "arv. However, the soil will need to
be retested for its soluble sulfate concentration after grading and compaction work is completed. Soluble
sulfate content of the surface soil should be reevaluated after grading and appropriate concrete mix
designs should be established based upon post- grading test results.
UTILITY TRENCH BACKFILL
All utility trench backfill should be compacted to a minimum relative compaction of 90 percent. Trench
backfill materials should be placed in lifts no greater than six inches in their loose state, moisture
conditioned or air -dried as necessary to achieve near optimum moisture conditions, and then
mechanically compacted in place to a minimum relative compaction of 90 percent. A representative of the
project geotechnical consultant should probe and test the backfills to verify adequate compaction.
EXTERIOR CONCRETE FLATWORK
To minimize cracking of concrete flatwork, the subgrade soil below concrete flatwork areas should first
be compacted to a minimum relative compaction of 90 percent. A representative of the project
geotechnical consultant should observe and verify the density and moisture content of the soil, and the
depth of moisture penetration prior to pouring concrete.
DRAINAGE
All final grades should be provided with positive gradients away from foundations and slopes to provide
rapid removal of surface water runoff to an adequate discharge point. No water should be allowed to be
pond on or immediately adjacent to foundation elements. In order to reduce water infiltration into the
subgrade soil, surface water should be directed away from building foundations to an adequate
discharge point. Subgrade drainage should be evaluated upon completion of the precise grading plans
and in the field during grading.
Sladden Engineering
January 7, 2009 -12- Project No. 544-08277
08-12 -650
LIMITATIONS
The findings and recommendations presented in this report are based upon an interpolation of the soil
conditions between the exploratory boring locations and extrapolation of these conditions throughout the
proposed building area. Should conditions encountered during grading appear different than those
indicated in this report, this office should be notified.
The use of this report by other parties or for other projects is not authorized. The recommendations of this
report are contingent upon monitoring of the grading operation by a representative of Sladden
Engineering. All recommendations are considered to be tentative pending our review of the grading
operation and additional testing, if indicated. If others are employed to perform any soil testing, this
office should be notified prior to such testing in order to coordinate any required site visits by our
representative and to assure indemnification of Sladden Engineering.
We recommend that a pre -job conference be held on the site prior to the initiation of site grading. The
purpose of this meeting will be to assure a complete' understanding of the recommendations presented in
this report as they apply to the actual grading performed.
ADDITIONAL SERVICES
Once completed, final project plans and specifications should be reviewed by use prior to construction to
confirm that the full intent of the recommendations presented herein have been applied to design and
construction. Following review of plans and specifications, observation should be performed by the Soil
Engineer during construction to document that foundation elements are founded on /or penetrate into the
recommended soil, and that suitable backfill soil is placed upon competent materials and properly
compacted at the recommended moisture content.
During grading, tests and observations should be performed by the Soil Engineer or his representative in
order to vcrifv that the grading is being performed in accordance with the project specifications. Field
density testing shall be performed in accordance with acceptable ASTM test methods. The minimum
acceptable degree of compaction should be 90 percent for subgrade soil and 95 percent for Class H
aggregate base as obtained by the ASTM D1557 -91 test method. Where testing indicates insufficient,
density, additional compactive effort shall be applied until retesting indicates satisfactory compaction.
Sladden Engineering
January 7, 2009 .13- Project No: 544 -08277
08-1.2 -650
REFERENCES
Blake, T., 2000, EQSEARCH, Computer Programs for Deterministic and Probabilistic Prediction of Peak
Horizontal Acceleration from Digitized California Faults.
California Building Code (CBC), (2007), California Building Standards Commission.
Cao T., Bryant, W.A., Rowshandel B., Branum D., Wills C.J., (2003), "The Revised 2002 California
Probabilistic Seismic Hazard Maps ".
Coachella Valley County Water District (CVCWD), 1975, Depth to Water Table Groundwater Contours
and Piezometer Well Readings, June -July 1975, Scale 2 " =1 mile.
GoogleEarth.com, 2007, Vertical Aerial Photograph for the La Quinta area, California, Undated, Variable
Scale. Reviewed at googlearth.com on January 7, 2009.
Hart, E. W., and Bryant, W. A., Revised 1997, Fault- Rupture Hazard Zones in California, Alquist- Priolo
Earthquake Fault Zoning Act with Index to Earthquake Fault Zones Maps: State of California,
Department of Conservation, Division of Mines and Geology Special Publication 42. 38 Pages.
Supplements 1 and 2 were added on 1999.
Jennings, Charles W. (Compiler), 1994, Fault Activity Map of California and Adjacent Areas, California
Division of Mines and Geology, Geologic Data Map No. 6.
Rogers T.H (compiler), Jenkins, O.P (edition) (1965), Geologic Map of California, Santa Ana Sheet, sixth
printing 1992, California Division of Mines and Geology, 1: 250,000.
Riverside County Land Information Systems (RCLIS), accessed January 7, 2009: available at
http://www.tima.co.riverside.ca.u,q/gis/gisdevelop.htmi
Tyley, ST, 1974, Analog Model Study of the Ground -Water Basin of the Upper Coachella Valley,
California, Geological Survey Water - Supply Paper 2027.
United States Geological Survey (USGS) (1980) La Quinta 7.5 Minute Quadrangle Map, 1:24000.
United States Geological Survey (USGS) (2001), "Detection and Measurement of Land Subsidence Using
Global Positioning System and Interferometric Synthetic Aperture Radar, Coachella Valley,
California, 1996 -98 ", Water - Resources Investigations Report 014193.
United States Geological Survey (USGS), Sneed, M., Brandt, J. T., 2007, "Detection and Measurement of
band Subsidence Using Global Positioning System Surveying and Interferometric Synthetic
Aperture Radar, Coachella Valley, California; 1996 -2005; Scientific Investigations Report 2007-
525'1.
United States Geological Survey (LJSGS) (2008), "Seismic Hazard Curves and Uniform Response Spectra,
Version 5.0.9 ", updated 10/06/2008.
Siadden Engineering
FIGURES ,
SITE LOCATION M A P
REGIONAL GEOLOGIC MAP
BOREHOLE LOCATION PHOTOGRAPH
SUBSIDENCE ZONES MAP
Sladden Engineering
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SITE LOCATION MAP FIGURE
Project Number: 544-=77
Report Number 08-12-6w
Date: January 7, 2009
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SUBSIDENCE ZONES
]FIGURE
4
Prcqect Number:
544-08
Re rt Number:
0 8-12 -650
Date:
lanua 7, 2009
Butiseuiou3 uappels
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APPFND1X A
FIELD EXPLORATION
For our field investigation six (6) exploratory bores were excavated on December 19, 2008 utilizing a
truck- mounted drill rig (Mobil B-61). Continuous logs of the materials encountered were made by a
representative of Sladden Engineering. Materials encountered in the boreholes were classified in
accordance with the Unified Soil Classification System which is presented in this appendix.
Representative undisturbed samples were obtained within our bores by driving a thin - walled steel
penetration sampler (California split spoon sampler) or a Standard Penetration Test (SPT) sampler with a
140 pound automatic -trip harmer dropping approximately 30 inches (ASTM 07586). The number of
blows required to drive the samplers 18 inches was recorded in 6 -inch increments and the blowcounts are
indicated on the boring logs.
The California samplers are 3.0 inches in diameter, carrying brass sample rings having inner diameters of
2.5 inches. The standard penetration samplers are 2.0 inches in diameter with an inner diameter of 15
inches. Undisturbed samples were removed from the sampler and placed in moisture sealed containers in
order to preserve the natural soil moisture content. Bulk samples were obtained from the excavation
spoils and samples were then transported to our laboratory for further observations and testing.
Sladden Engineering
UNIFIED SOIL CLASSIFICATION SYSTEM
MAJOR DMSIONS
TYPICAL NAMES
CLEAN GRAVELS
GW
WELL GRADED GRAVEL-SAND MIXTURES
I,
GRAVELS
WITH LITTLE OR NO
in
FINES
GP
POORLY GRADED GRAVELS, GRAVEL-SAND
g
N
MTXTURFS
z
MORE THAN HALF
G?vT
SILTY GRAVELS, POORLY-GRADED GRAVEL-
COARSE FRACTION IS
SAND-SILT MIXTURES
O x
LARGER THAN No.4 STFVF,
GRAVELS WITH OVF;R
GC
CLAYEY GRAVELS, POORLY GRADED GRAVEL-
E"
cant
SIZE
120/4 FINES
SAND -CLAY MIXTURES
�
SW
WELL GRADED SANDS, GRAVELLY SANDS
SANDS
CLEAN SANDS WITH
LITTLE OR NO FINES
U x
SP
POORLY GRADED SANDS, GRAVELLY SANDS
xMORE
SM
SILTY SANDS, POORLY GRADED SAND-ST.LT
THAN HALF
w
COARSE FRACTION ?S
MIXTURES
SMALLER THAN No.4
SANDS WITH OVER
SIEVE SIZE
12% FINES
CLAYEY SANDS, POORLY GRADED SAND-CLAY
Sc
MIXTURES
INORGANIC SILTS & VERY FINE SANDS, ROCK
ML
FLOUR, SILTY OR CLAYEY FINE SANDS, OR
CLAYEY SILTS WITH SLIGHT PLASTICITY
h
STT,TS AND CLAYS
INORGANIC CLAYS OF LOW TO MEDIUM
LIQUID LIMIT LESS THAN 50
CL
PLASTICITY. GRAVELLY CLAYS, SANDY
CLAYS SILTY CLAYS CLEAN CLAYS
OL
ORGANIC CLAYS AND ORGANIC SWfY CLAYS
cn
A cn w
z�m
OF LOW PLASTICITY
[. c
INORGANIC smas, MICACEOUS OR
C7 0
MH
D1A'I'OMACIOUS FINE SANDY OR SILTY SOILS,
w _ z
SILTS AND CLAYS: LIQUID LIMIT GREATER THAN
ELASTIC SILTS
INORGANIC CLAYS OF HIGH PLASTICITY, FAT
cs
CH
t,
60
CLAYS
w
x
O
OH
ORGANIC CLAYS OF MEDIUM TO HIGH
PLASTICITY, ORGANIC SILTS
HIGHLY ORGANIC SOIIS
Pt
PEAT AND OTHER HTGHLY ORGANIC SOILS
EXPLANATION OF BORE LOG SYMBOLS
=California Split -spoon Sample
®Unremvered Sample
CUStandard Penetration Test Sample
Note: The stratification lines on the
borelogs represent the approximate
Groundwater depth boundaries between the soil types; the
transition may be gradual.
A -1
BORE LOG
SLADDEN ENGINEERING
Drill Rig: Mobil B-61
Date Drilled: 72/19/2008
Elevation:
60 Feet (AMSL)
florin No: BH -1
nx,
o
o
Description
°'
c`
U
tr1Oi
5
0
�'
U
L
3
x
re
U)
A
A
c
3/4/6
1
2
49
*13
*113
2
'
Silty Sand (SM); yellowish brown, moist, loose, fine- grained,
4
micaceous (Fill).
4/5/6
6
Silty Sand (SM); yellowish brown, moist, loose, fine - grained (Native).
24.3
5.2
91.6
R
3/6/7
80.5
24.2
85.5
10
any Silt (ML); ye owls rown, moist, me lum stt ow p asticity,
12
micaceous.
2/3/3
91.5
16.9
14
16
Sandy Silt (ML); light olive brown, medium stiff, low plasticity,
micaceous.
is
3/6/11
62.1
18.5
97.8
ZU
Sandy Silt (ML); dark yellowish brown, moist, stiff, low plasticity.
22
3/3/4
21.5
4.8
24
26
Silty Sand (SM); yellowish brown, moist, loose, fine - grained.
28
5/8/12
89.9
20.8
95.9
30
Sandy Silt (ML); pale yellow, slightly moist, stiff, low plasticity.
32
4/6/8
26.9
6.7
34
=
Silty Sand ( light olive brown, slightly moist, medium dense, fine.
grained.
•
38
416111
95.5
19.3
85.1
40
Sandy Silt (ML); mottled light gray and orangish brown, moist, s-6 ,
low plasticity.
44
4/617
64.6
16.5
Sandy Silt (ML); mottled light gray and orangish brown, moist, stiff,
46
low plasticity.
48
6/10/13
90.2
24.4
97.5
Clayey Silt (ML); olive brown, moist, stiff, medium lastieity.
Completion Notes_
PROPOSED LA QUINTA RESORT EXPANSION
49499 EISENHOWER DRIVE, LA QUINTA, CALIFORNIA
Project No: 544 -08277
Page
1
Report No: 08-1.2 -650
BORE LOG
SLADDEN ENGINEERING
Drill Rig: Mobil B-61
Date Drilled: 12 /19/2008
Elevation:
60 Feet (AMSL)
Boring No: BH -1 (2)
o
C
a
zy
o
g
v
c
o
E
:s
Description
G
U
fa
to
3
C'
V
R
E
o
Q
z
5
cn
I m
m
52
54
6/6/7
30.6
4.7
Silty Sand (SM); light yellowish rown, slightly moist, medium dense,
fine - grained.
58
7/10/10
86.9
31.5
90.8
60
Silty Clay (CL); Ggfit olive Frown, moiststiff, medium to g
62
21asticity.
Terminated at -61.5 ft. bgs.
No Bedrock Encountered.
No Groundwater or Seepage Encountered.
66
68
70
72
79
76
7$
AO
82
at
8(i
88
9q
92
94
96
98
i
Completion Notes:
PROPOSED LA QUINTA RESORT EXPANSION
"Optimum Moisture /Maximum IUensity
49499 EISENHOWER DRIVE, LA QUJNTA, CALIFORNIA
Project No: 544 -08277
Page
2
Report No: 08 -12 -650
Pavement - 4" AC /6" Bascrock
BORE LOG
SLADDEN ENGINEERING
Drill Rig: Mobil B -61 Date Drilled: 12/19/2008
Elevation:
60 Feet (AMSL) Boring No: BH -2
a
o
?�
o
Description
6/6/7
60.9
14.0
95.3
2
Sandy Silt (M1.); yellowish brown, moist, medium stiff, low plasticity
4
(Fill).
3/4/5
79.0
18.5
84.8
Sandy Silt (ML); yellowish brown, moist, medium stiff, low plasticity,
6
micaceous (Native).
8
3/4/7
93.5
31.4
82.5
10
Sandy Silt (ML); light olive brown, moist, medium stiff, low plasticity.
72
14
3/4/4
28.4
4.7
16
'
Silty Sand (SM); light yellowish brown dry, loose, fine grained.
18
`:
518/11
963
22.2
89.5
20
t ; mottled pale yellow and olive yellow, moist, stiff, ow
22
plasticity.
3/4/5
30.7
6.2
24
26
Silty an ; ,t yellowish rown, slight] moist, Do
y
grained, micaceous.
28
416177
37.1
4.9
85.3
Silty Sand (SM); light yellowish brown, slightly moist, loose, fine -
12
grained (ML in shoe).
4/4/5
68.4
18.4
34
36
any Silt (ML); molt pale yellow an olive yellow, moist, stiff,
low plasticity.
38
7/8/9
81.9
4.4
94.4
40
Sandy Silt (ML); mottled pale yellow and olive yellow, moist, stiff,
42
low plasticity.
3/517
90-3
22.8
44
Sandy Silt (ML); mottled pale yellow and olive yellow, moist, stiff,
low plasticity.
Sandy Silt (ML); mottled pale yellow and olive yellow, moist, stiff,
5/8113
' 80.0
6.4
90.3
low plasticity.
Completion Notes:
PROPOSED LA QUINTA RESORT EXPANSION
49499 EISENHOWER DRIVE, LA QUINTA, CALIFORNIA
Project No: 544-08277
Wage
3
Report No: 08 -12 -650
�~
BORE LOG
SLADDEN ENGINEERING
Drill Rig: Mobil 13-67 ---7
Date Drilled: 12%19/2008
Elevation:
60 Feet (AMSL)
Boring No: BH -2 (2)
v
o�
5
S
°
Description
E
52
54
517/7
64.7
17.7
56
Sandy Silt (ML); light yellowish brown, moist, stiff, low plasticity.
58
8/10/13
86.4
28.2.
94.4
60
Sandy Silt (ML); mottled light gray and yellowish brown, slightly
62
moist stiff, low Plasticity.
Terminated at -61.5 ft. bgs.
64
No Bedrock Encountered.
No Groundwater or Seepage Encountered.
68
70
72
74
76
78
S0
A2
84
db
88
90
92
94
9R
F1001
Completion Notes:
PROPOSED LA QUINTA RESORT EXPANSION
49499 EISENHOWER DRIVE, LA QUINTA, CALIFORNIA
Project No: 544-08277
Page
Report No: 08- 12-650
Pavement = 2" AC /4" Baserock
BORE LOG
SLADDEN ENGINEERING
Drill Rig: Mobil 8 -61.
Date Drilled: 12/19/2008
Elevation:
60 Feet (AMSL)
Boring No: BH -3
X
E
o
h
Q
Description
Q.
lJ
o
U)
U1
Silty Sand (SM); yellowish brown, moist, fine - grained (Fill).
2
4
2/5/6
26.0
8.0
95.9
Silty Sand (SM); yellowish brown, moist, loose, fine - grained,
6
micaceous (Native).
8
4/8/10
17.2
4,6
1.01.9
10
Silty Sand (SM); yellowish brown, moist, medium dense, fine - grained,
12
,
3/3/3
8.6
3.9
14
16
,=
Sand (SP); yellowish brown, moist, loose, fine - grained.
18
"
4/6/8
96.2
34.1
.86.3
20
Sit (ML); mottled tg t olive brown aFd yeflowisS 6rown, moist, stiff,
low to medium plasticity.
4/6/7
21.1
3.9
2a
26
Silty Sand (SM); yellowish brown, dry, medium dense, fine - grained.
28
4/5/6
58.7
8.3
84.8
30
any Silt (ML); yellowish rown, slightly moist, medium stiff, ow
32
plasticity.
34
Terminated at -31-5) ft. bgs,
No Bedrock Encountered.
No Groundwater or Seepage Encountered.
36
38
40
42
44
46
48
50
Completion Notes:
PROPOSED LA QUINTA RESORT EXPANSION
49499 EISENHOWER DRIVE, LA QUINTA, CALIFORNIA
Project No: 544- 08277
Page
5
Report No: 08- 12-650
Pavement = 3" AC /4" Baseroek
BORE LOG
SLADDEN ENGINEERING Drill Rig: Mobil B-61 I Date Drilled: 12/19/2008
Elevation: 60 Feet (AMSL) I Borine No: BH -4
a
�
b
O
Description
O.
V
tI
G
0
'u
roll.
~G
2
IL
R
2
1/2/1
2
0
27.6
"12
"116
2
`•
Silty Sand (SM); yellowish brown, moist, very loose, fine - grained
I I
q
3/4/4
Silty Sand (SM); yellowish brown, moist, very loose, fine - grained
25.1
6.9
92.7
6
(Native).
8
4/7/1
91.4
25.8
92.4
10
Clayey ► t ; inott yellowish rown and brownish yellow,
12
moist, stiff, medium plasticity with rootlets.
14
214/3
43.1
7.5
16
Silty Sand (SM); light olive brown, slightly moist, loose, fine - gained.
i
4/10/12
23.2
6.8
96.4
20
Silty Sand (SM); light olive brown, slightly moist, medium dense,
22
micaceous.
24
3/4/4
32.3
6.9
26
° ; °
Silty Sand (SM); light olive brown, slightly moist, loose, fine- grained.
28
5/9/11
86.8
27.6
94.1
Sandy Silt (ML); olive brown, moist, stiff, low plasticity.
32
34
3/4/6
66.5
21.7
Sandy Silt (ML); olive brown, moist, Stiff, low plasticity.
38
4/5/6
94.4
32.6
87.1
40
Sandy Silt (ML), olive brown, moist, medium stiff, low plasticity.
42
44
3/4/6
80.9
22.8
Sandy Silt (ML); olive brown, moist, stiff, low Plasticity.
46
48
50
Sandy Silt (ML); olive brown, moist, stiff, low to medium plasticity.
4/8/9
92.5
29.6
93.2
Completion Notes:
PROPOSED LA QUINTA RESORT EXPANSION
Terminated at -51.5 ft. bgs.
49499 EISENHOWER DRIVE, LA QUINTA, CALIFORNIA
Project No: 544 -08277
page
6
No Bedrock/ Groundwater /Seepage Encountered.
Pavement = 3" AC /0" Bascrack
Re rt No: 08 -12 -650
BORE LOG
SLADDEN ENGINEERING
Drill Rig: Mobil B77-1
Date Drilled: 1.2119/2008
Elevation: 60 Fect (AMSL)
Boring No: BH -5
a
$
w
75
1
Description
m
U
o
s
p
y
y
to
V)
oo _
ro
cry
I 38
24
A
V
i
Silty Sand (SM); yellowish brown, moist, fine- grained (Fill).
2
4
516/7
25.4
6.7
101.9
6
Silty Sand (SM); yellowish brown, moist, loose, fine- grained (Native).
8
2/3/5
83.6
20.6
10
l2
Sandy Silt (ML); olive brown, moist, medium stiff, low plasticity.
14
4/6/10
40.7
4.5
16-
Silty Sand (SM ); very pale brown, slightly moist, loose, fine grained.
18
:-
6/7/9
12.5
2.5
20
22
'
Silty Sand (SM); light olive brown, medium dense, fine- grained.
Terminated at °21.5 ft. bgs.
24
No. Encountered.
No Groundwater or Seepage Encountered.
26
2s
30
32
34
36
38
40
42
44
4(i
- 48
50
Completion Notes:
PROPOSED LA QUINTA RESORT EXPANSION
49499 EISENHOWER DRIVE, LA QUINTA, CALIFORNIA
Project No: 544 -08277
Page
%
Report No: 08 -12 -650
Pavement = 3" AC /0" Baserock
BORE LOG
*JL SLADDEN ENGINEERING
Drill Ri : Mobil t3 -61
Date Drilled; 12/19/2008
Elevation:
60 Feet (AMSL)
Boring No: 13H -6
e
o
C
CL
C
O
y
R
a
Description
Ll
C 1
w
C
O
v
u
p
x
cn
m
to
w
aQ
a°
A
C7
Silty Sand (SM); yellowish brown, moist, fine- grained (Fill).
2
4
8/9/12
202
5.7
104.0
Silty Sand (SM); yellowish brown, moist, medium dense, fine - brained
6
(Native).
d
3/415
72.4
13.5
10
Sandy Silt (ML); olive brown, moist, stiff, low plasticity.
t2
14.
2/4/4
34.7
4.0
Silty Sand (SM); light olive brown, slightly moist, loose, fine- grained.
76
314/4
91.0
24.3
20
Sandy Silt (ML); olive brown, moist, medium stiff, low plasticity.
22
Terminated at -21.5 ft. bgs.
24
No Bedrock Encountered.
No Groundwater or Seepage Encountered.
26
2R
30
32
34
36
38
40
42
44
46
411
50
Completion Notes:
PROPOSED LA QUINTA RESORT EXPANSION
49499 EISENHOWER DRIVE, LA QUINTA, CALIFORNIA
.Project No. 544 -08277
Page
S
Report No: 08-12 -650
Pavement = 3-5" AC /0" Baserock
APPENDIX B
LABORATORY TESTING .
Representative bulk and relatively undisturbed soil samples were obtained in the field and returned to
our laboratory for additional observations and testing. I.,aboratory testing was generally performed in
two phases. The first phase consisted of testing in order to determine the compaction of the existing
natural soil and the general engineering classifications of the soil underlying the site. This testing was
performed in order to estimate the engineering characteristics of the soil and to serve as 3 basis for
selecting samples for the second phase of testing. The second phase consisted of soil mechanics testing.
'Phis testing including consolidation, shear strength and expansion testing was performed in order to
provide a means of developing specific design recommendations based on the mechanical properties of
the soil.
CLASSIFICATION AND COMPACTION TESTING
Unit Weight and Moisture Content Determinations: Each undisturbed sample was weighed and
measured in order to determine its unit weight. A small portion of each sample was then subjected to
testing in order to determine its moisture content. This was used in order to determine the dry density of
the soil in its natural condition. The results of this testing are shown on the Boring Logs.
Maximum Density- Optimum Moisture Determinations: Representative soil types were selected for
maximum density determinations. This testing was performed in accordance with the ASTM Standard
131557 -91, Test Method A. The results of this testing are presented graphically in this appendix. The
maximum densities are compared to the field densities of the soil JD order to determine the existing
relative compaction to the soil. This is shown on the Boring Logs, and is useful in estimating the strength
and compressibility of the soil.
Classification Testing: Soil samples were .selected for classification testing. This testing consists of
mechanical grain size analyses. This provides information for developing classifications for the soil in
accordance with the Unified Soil Classification System which is presented in the preceding appendix.
This classification system categorizes the soil into groups having similar engineering characteristics. The
results of this testing is very useful in detecting variations in the soil and in selecting samples for further
testinb.
SOIL MECHANIC'S TESTING
Expansion Testing: One (1) bulk sample was selected for Expansion testing. Expansion testing was
performed in accordance with the UBC Standard 18 -2. This testing consists of remolding 4 -inch diameter
by 1 -inch thick test specimens to a moisture content and dry density corresponding to approximately 50
percent saturation. The samples are subjected to a surcharge of 144 pounds per square foot and allowed
to reach equilibrium. At that point the specimens are inundated with distilled water. The linear
expansion is then measured until complete.
Direct Shear Tests: Four (4) samples were selected for Direct Shear Testing. This test measures the shear
strength of the soil under various normal pressures and is used to develop parameters for - foundation
design and lateral design. Tests were performed using a recompacted test specimen that was saturated
prior to tests. Tests were performed using a strain controlled test apparatus with normal pressures
ranging from 800 to 2300 pounds per square foot.
Sladden Engineering
Consolidation Test: Three (3) relatively undisturbed sample were selected for consolidation testing. For
this test, a one -inch thick test specimen was subjected to vertical loads varying from 575 psi to 11520 psi
applied progressively. The consolidation at each load increment was recorded prior to placement of each
subsequent load. The specimens were saturated at 575 psf or 720 psi load increment.
Sladden Engineering
APPENDIX B
LABORATORY TESTING
i
0
Sladden Engineering
Sladden Engineering
450 Egan Avenue, Beaumont CA 92223 (951) 845 -7743 Fax (951) 845 -8863
Project Number:
Project Name:
Lab .lD Number:
Sample Location:
Description:
Maximum Density:
Optimum Moisture:
145
140
135
130
P. 125
A
120
A.
115
110
105
Maximum Density /Optimum Moisture
ASTM D698/D1557
544 -08277
La Quinta Resort Expansion
LN6 -08713
BH -1 Bulk 1@ 0 -5'
Olive Silty Sand (SM)
113 pef
13%
Sieve Size % .Retained
3/4"
3/8"
#4
January 23, 2009
ASTM..D -)557 A
Rammer Type: Machine
100-1
0
s 10 Is 20 25
Moisture Content, %
Buena Park • Palm Desert • Hemet
NINE
'M
MIN
No
=2.65..2.70,2.
MEN
■
��
_
MMMM
11.0
®��o�■
■■
Be
100-1
0
s 10 Is 20 25
Moisture Content, %
Buena Park • Palm Desert • Hemet
Sladden Engineering
f
450 Egan Avenue, Beaumont CA 92223 (951) 845 -7743 Fax (951) 845 -8863
Maximum Density /Optimum Moisture
ASTM D698/D1557
Project Number. 544 -08277 December 31, 2008
Project Name: La Quinta Resort Expansion
Lab ID Number: LN6 -08713 ASTM D-1557 A
Sample Location: BH4 Bulk 2 @ 0 -5' Rammer Type: Machine
:Description: Olive Silty Sand (SM)
Maximum Density: 116 pef
Optimum Moisture: 12%
Sieve Size % Retained
3/4"
3/8"
#4
145
140
135
130
w
125
d
�+
120-
A
• �
r
I1S.
110.
105-
100
0 5 t0 15 20 25
Moisture Content, %
Buena Park - Palm Desert - Hemet
MIN
MM
WIN
"Ll
, Sg =2.65,2.?O,
,
■
■�
ONE
■��
WEINE
dmoo
\\
■■
EM
'
I
■■
III
I
■
■■"■■
ice""
--'�
■gym
-
®=44�:��
_■°■■111111110111®■
0 5 t0 15 20 25
Moisture Content, %
Buena Park - Palm Desert - Hemet
Sladden Engineering
450 Egan Avenue, Beaumont, CA 92223 (951) 845 -7743 Fax (951) 845 -8863
Job Number:
Job Name:
Lab 1D Number:
Sample JD:
Soil Description
Expansion Index
ASTM D 4829/UBC 29 -2
544 -08277
January 23, 2009
La Quinta Resort Expansion
LN6 -08713
BH -1 Bulk 't @a, 0 -5'
Olive Silty Sand (SM)
Wt of Sail + Ring:
554.8
Wei ght of Ring:
195.2
Wt of Wet Soil:
359.6
Percent Moisture:
12.8%
Wet Density, f
109.0
Dry Denstiy, pcf.
96.6
Saturation: 1 46.4
Expansion Rack # 3
Date/Tinic
12/29/200$
3:00 PM
Initial Reading
0.0000
Final.Reuding
0.0036
Expansion Index
(Final - Initial) x 1000
Corrected Expansion Index
4
2
Buena Park - Palm Desert - Hemet
Sladden Engineering
450 Egan Avenue, Beaumont, CA 92223 (951) 845 -7743 Fax (951) 845 -8863
Expansion Index
AST M. D 4829/UBC 29 -2
Job Number: 544 -08277 December 31, 2008
Job Namc: La Quinta Resort Expansion
Lab 1D Number: LN6 -08713
Sample 10: BH-4 Bulk 2 @ 0 -5' .
Soil Dcscription: Olive Silty Sand (SM)
Wt of Soil + Ring:
560.3
Weigbt of Ring:
188.8
Wt of Wet Soil:
371.5
Pcrccnt Moisture:.
11.5%
Wet Density, pcf:
112.6
Dry Densti , cf:
1 101.0
% Saturation: 46.4
Expansion Rack # 3
Date/Time
12/29/2008
1 2:20 PM
Initial. Readirla
0.0000
Final Reading
0.0007
Expansion Index i
(Final - Initial) x 1000
Corrected Expansion Index 0
Buena Park • Palm Desert • Hemet
5ladden Engineering
450 Egan Avenue, Beaumont, CA 92223 (951) 845 -7743 Fax (951) 845 -8863
Direct Shear ASTM D 3080 -04
(modified for unconsolidated, undrained conditions)
Job Number: 544 -08277 January 23, 2009
Job Name La Quinta Resort Expansion Initial Dry Density: 101.6 pcf
Lab 1D No. LN6 -08713 Initial Mosturc Content: 12.9 %
Sample ID BH -1 Bulk 1 @ 0 -5' Peak Friction Angle (0): 32°
Classification Olive Silty Sand (SM) Cohesion (c): 260 psf
Sample Type Remolded @ 90% of Maximum Density
Test Results
1
2
3
4
Average
Moisture Content, %
23.2
23.2
23.2
23.2
23.2
Saturation, %
95.2
95.2
95.2
95.2
95.2
Normal Stress, k s
0.702
1.404
2.809
5.618
Pcak Stress, k s
0.658
1.184
2.061
3.794
6.0
5.0
4.0
3.0
a 2.0
W)
1.0
0.0
• Pcak Stress Linear (Peak Stress)
0 1 2 3 4 5 6
Normal Stress, kps
Buena Park • Palm Desert • Hemet
Sladden Engineering
450 Egan Avenue, Beaumont, CA 92223 (951) 845 -7743 Fax (951) 845 -8863
Direct Shear ASTM D 3080 -04
(modified for unconsolidated, undrained conditions)
Job Number: 544 -08277 December 31, 2008
Job Name La Quinta Resort Expansion initial Dry Density: 104.4 pef
Lab ID No. LN6 -08723 Initial Mosture Content: 11.9 %
Sample 1D BH-4 Bulk 2 @ 0 -5' Peak Friction Angle (0): 33°
Classification Olive Silty Sand (SM) Cohesion (c): 250 psf
Sample Type Remolded @ 90% of Maximum Density
Test Results
1
2
3
4
Average
Moisture Content, %
19.4
19.4
19.4
19.4
19.4
Saturation, %
85.3
85.3
85.3
85.3
85.3
Normal Stress, k s
0.702
1.404
2.809
5.618
Peak Stress, kps
0.680
1.140
2.083
3.816
6.0
5.0
4.0
N
w 3.0
2.0
1.0
0.0
• Peak Stress Linear (Peak Stress)
... .......... .. ...
i
0 1 .2 3 4 5 6
Normal Stress, kpst
Buena Park • Palm Desert - Hcmet
Sladden Engineering
460 Egan Avenue, Beaumont. CA 92223 (951) 845 -7743 Fax (951) 845 -8863
Direct Shear ASTM D 3080 -04
(modified for unconsolidated, undrained conditions)
Job Number: 544 -08277 January 23, 2009
Job Name La Quinta Resort Expansion Initial Dry Density: 101.6 pcf
Lab ID No. LN6 -08713 Initial Mosture Content: 12.9 %
Sample ID 1314-1 Bulk 1 @ 0 -5' Peak Friction Angle (fd): 32°
Classification Olive Sandy Silt (ML) Cohesion (c): 260 psf
Sample Type Remolded @ 90% of Maximum Density
Test Results
1
2
3
4
Average
Moisture Content. %
23.2
23.2
23.2
23.2
23.2
Saturation,.%
95.2
95.2
95.2
95.2
95.2
Normal Stress, k s
0.702
1.404
2.809
5.618
Peak Stress, k s
0.658
1.184
2.061
3.794
6.0
5.0
Vi
24.0
N
h
47
b 3.0
2.0
1.0
0.0
0 1 2 3 4 5 6
Normal Stress, kps
• Peak Stress Linear (Peak Stress)
Buena Park • Palm Desert • Hemet
t
Sladden Engineering
450 Egan Avenue, Beaumont, CA 92223 (951) 845 -7743 Fax (951) 845 -8863
Direct Shear ASTM D 3080 -04
(modified for unconsolidated, undrained conditions)
Job Number: 544 -08277 January 23, 2009
Job Name La Quinta Resort Expansion Initial Dry Density: 104.4 pcf
Lab ID No. LN6 -08713 initial Mosture Content: 11.9 %
Sample ID BH-4. Bulk 2 @ 0 -5' Peak Friction Angle (0): 33°
Classification Olive Silty Sand (SM) . Cohesion (c): 250 psf
Sample Type Remolded @ 90% of Maximum Density
Test Results
1
2
3
4
Average
Moisture Content, %
19.4
19.4
19.4
19.4.
19.4
Saturation, %
85.3
85.3
85.3
85.3
85.3
Normal Stress, kps
0.702
1.404
2.809
5.618
IPcak Stress, k s
0.680
1.140
2.083
3.816
MU
Y 4.0
3.0
s 2.0
1.0
0.0
0 1 2 3 4 5 6
Normal Stress, kps
Peak Stress Linear (Peak Stress)
Buena Park • Palm Desert • Hemet
Sladden Engineering
450 Egan Avenue, Beaumont, CA 92223 (951) 845 -7743 Fax (951) 845 -8863
Direct Shear ASTM D 3080 -04
(modified for unconsolidated, undrained conditions)
Job Number: 544 -08277 January 23, 2009
Job Name La Quinta Resort Expansion initial Dry Density: 93.6 pcf
Lab ID No. LN6 -08713 initial Mosture Content: 6.8 %
Sample 1D BH -4 #5 @ 20' Peak Friction Angle (U): 34°
Classification Cray Brown Silty Sand (SM) Cohesion (c): 230 psf
Sample Type Undisturbed
Test Results
1
2
3
4
Average
Moisture Content, %
27.9
27.9
27.9
27.9
27.9
Saturation, %
90.3.
95.0
92.6
98.5
94.1
Normal Stress. kps
0.702
1.404
2.809
5.618
Peak Stress, k s
0.680
1.162
2.259
4.035
6.0
S.A
4.0
w
w' 3.0
2.0
1.0
0.0
u Peak Stre; -s Linear (Peak Stress)
0 1 2 3 4 5 6
Normal Stress, kps
Buena Park - Palm Desert - Hemet
Sladden Engineering
450 Egan Avenue, Beaumont, CA 92223 (951) 845 -7743 Fax (951) 845 -8863
Direct Shear ASTM D 3080 -04
(modified for unconsolidated, undrained aonditions)
Job Number: 544 -08277 January 23, 2009
Job Name La Quinta Resort Expansion Initial Dry Density: 96.5 pcf
Lab ID No. LN6 -08713 Initial Mosture Content: 18.5 %
Sample ID BH -1 #5 @'20' Peak Friction Angle (PJ): 25°
Classification Olive Silty Clay (CL) w /Interbedded Brown Silty Sand (SM) Cohesion (c): 430 psf
Sample Type Undisturbed
}
Test Results
X
2
3
4
Average
Moisture Content, %
19.5
19.5
19.5
19.5
19.5
Saturation, %
76.5
61.8
66.9
78.5
70.9
Normal Stress, kps
0.702
1.404
2.809
5.618
Peak Stress, kps
0.680
1.031
1.908
2.939
6.0
5.0
4.0
3.0
iti
2.0
1.0
o.o
r Peak Stress Linear (Peak Stress)
'�ailA moll
�p M NOMMW I M -
M"M ���
0 1 2 3 4 5 6
Normal Stress, lops
Buena Park • Palm Desert • Hemet
Sladden Engineering
450 Egan Avenue, Beaumont, CA 92223 (951) 845 -7743 Fax (951) 845 -8863
Gradation
ASTM C117 & C136
Project Number: 544 -08277 January 23,2009
Project Name: La Quinta Resort Expansion
Lab 1D Number: LN6 -08713
Sample ID: BH -1 Bulk 1@ 0 -5' Soil Classification: SM
Sieve
Sieve
Percent
Size, in
Sire, mm
Passing
2"
50.8
100.0
1 1/2"
38.1
100.0
1 if
25.4
100.0
3/4"
19.1
100.0
1/2 n
12.7
99.8
3/8"
9.53
99.4
#4
4.75
98.7
#8
2.36
98.3
#16
1.18
97.1
#30
0.60
95.8
#50
0.30
93.4
#100
0.15
82.2
#200
0.075
49.0
Buena Park • Palm Desert - Hemet
Sladden Engineering
450 Egan Avenue, Beaumont, CA 92223 (951) 845 -7743 Fax (951) 845 -8863
Gradation
ASTM C1 17 & C136
Project Number:
54408277
December 31,2008
Project Name:
La Quinta Resort Expansion
Lab M Number:
LN6 -08713
Sample ID:
BH4 Bulk 2 r@ 0-5'
Soil Classification: SM
Sieve
Sieve
Percent
Size, in
Size, mm
Passing
2"
50.8
10010
1 1/211
38.1
100.0
.1 "
25.4
99.6
3/4"
19.1
99.2
1/2"
12.7.
98.8
3/8"
9.53
98.4
#4
4.75
97.9
#8
2.36
97.1
#16
1.18
95.7
#30
0.60
93.8
#50
0.30
86.7
#100
0.15
58.8
#200
0.075
27.6
11UGLLa C dL& - I LIIIII "V.5VI L - I JVJIML
Sladden Engineering
450 Egan Avenue, Beaumont, CA 92223 (951) 845 -7743 Fax (951) 845 -8863
Gradation
ASTM C117 & C136
Project Number: 544 -08277 December 31, 2008
Project Name: La Quinta Resort Expansion
Lab ID Number: LN6 -08713
Sample 1D: BH -1 #2 @ 5'- Soil Classification: SM
Sieve
Sieve
Percent
Size, in
Size, nun
Passing
1"
25.4
100.0
3/4"
19.1
100.0
1/2,,
12.7
100.0
3%8"
9.53
100.0
#4
4.75
100.0
#8
2.36
100.0
#16
1.18
100.0
#30
0.60
100.0
#50
0.30
98.6
#100
0.15
82.0
#200
0.074
24.3
100.000 1(.).110(► 1.000 0.100 0.010 0.001
SiCVc Size, mm
Buena Park • Palm Desert • Hemet
1"K
I
0
°
is
i
�
100.000 1(.).110(► 1.000 0.100 0.010 0.001
SiCVc Size, mm
Buena Park • Palm Desert • Hemet
3
Sladden Engineering
450 Egan Avenue, Beaumont, CA 92223 (951) 845 -7743 Fax (951) 845 -8863
Gradation
ASTM Cl 17 & C136
Project Number:
544 -08277
December 31, 2008
Project Name:
La Quinta Resort Expansion
Lab YD Number:
LN6 -08713
Sample ID:
BH -3 #1 @'5'
Soil Classification: SM
Sieve
Sieve
Percent
Size, in
Size, mm
Passing
1 "
25.4
100.0
3/4"
19.1
100.0
1/211
12.7
100.0
3/8"
9.53
100.0
#4
4.75
100.0
#8
2.36
100.0
#16
1.18
100.0
#30
.0.60
99.8
#50
0.30
95.7
#100
0.15
62.8
#200
0.074
26.0
j I'll � III ���
I
MOM
ROME
Jill .
NUM I�II��mn n�
Buena Park • Palm Desert • Hemet
Sladden Engineering
450 Egan Avenue, Beaumont, CA 92223 (951) 845 -7743 Fax (951) 845 -8863
Gradation
ASTM C117 & C136
Project Number: 54408277 December 31, 2008
Project Name: La Quints Resort Expansion
Lab ID Number: LN6 -08713
Sample ID: BH -3 #3 @ 15' Soil Classification: SP
Sieve
Sieve
Percent
Size, in
Size, nun
Passing
1 "
25.4
100.0
3/4"
19.1
100.0
1/2"
12.7
100.0
3/8"
9.53
100.0
#4
4.75
100.0
#8
2.36
100.0
#16
1.18
99.9
#30
0.60
99.7
#50
0.30
86.8
#1.00
0.15'
30.8
#200
0.074
8.6
IN
100.000 10.000 1.000 0.100 0.010 O.00I
Sieve Size, mtn
Buena Park • Palm Desert • Hemet
IN
11111
NE
100.000 10.000 1.000 0.100 0.010 O.00I
Sieve Size, mtn
Buena Park • Palm Desert • Hemet
Siadden Engineering
450 Egan Avenue, Beaumont, CA 92223 (951) 845 -7743 Fax (951) 845 -8863 -
Gradation
ASTM C117 & C136
Project Number: 544 -08277 December 31, 2008
Project Name: La Quinta Resort Expansion
Lab ID Number: LN6 -08713
Sample ID: BH4 #4 @ 15' Soil Classification: SM
Sieve Sieve Percent
Size, in Size, mm Passing
1 " 25.4 100.0
3/4" 19.1 100.0
1/2,, 12.7 100.0
3/8" 9.53 100.0
#4 4.75 100.0
#8 2.36 100.0
#16 1.18 100.0
#30 0.60 100.0
#50 0.30 99.4
#100 0.15 90.8
#200 0.074 43.1
100.000
10.000 1.000 0.10}
Sieve Size, mm
Buena Park • Palm Desert - Hemet
0.010 - O.o01
MINE
Is
HIN
IM
�u
n
MEN
lulls
91
mmim
100.000
10.000 1.000 0.10}
Sieve Size, mm
Buena Park • Palm Desert - Hemet
0.010 - O.o01
Sladden Engineering
450 Egan Avenue, Beaumont, CA 92223 (951) 845 -7743 Fax (951) 845 -8863
Gradation
ASTM C117 &t C136
Project Number: 544 -08277 December 31, 2008
Project Name: La Quinta Resort Expansion
Lab ID Number: LN6- 08713
Samp)e ID: 1314-5 #1 @ 5' Soil Classification: SM
Sieve
Sieve
Percent
Size, in
Size, mm
Passing
1"
25.4
100.0
3/4"
19.1
100.0
1/2"
12.7
100.0
3/8"
9.53
100.0
#4
4,75
100.0
#8
2.36
100.0
#16
1.18
99.8
#30
0.60
99.3
#50
0.30
96.4
#100
0.15
72.9
#200
0.074
25.4
100.000 10.000 1.000 0.100 0.010 0.001
Sieve Size, mm
Buena Park • Palm Dcsert • Hemet
��■�nn
niiii�
I
INN
NNE
,si�n■�
OEM
ou■■
III
100.000 10.000 1.000 0.100 0.010 0.001
Sieve Size, mm
Buena Park • Palm Dcsert • Hemet
Sladden Engineering
450 Egan Avenue, Beaumont, CA 92223 (951) 845 -7743 Fax (951) 845 -8863 .
Gradation
ASTM C117 & C136
Project Number:. 544 -08277 December 31, 2008
Project Name: La Quinta Resort Expansion
Lab ID Number: LN6- 08713
Sample 1D. BH =6 #3 @ 15' Soil Classification: SM
Sieve Sieve Percent
Size, in Size, mm Passing
1 " 25.4 100.0
3/4" 19.1 100.0
1/2" 12.7 100.0
3/8" 9.53 100.0
#4 4.75 100.0
#8 2.36 100.0
#16 1.18 100.0
#30 0.60 99.7 "
#50 0.30 99.1
#100 0.15 88.8
Jill F.,
IWY� �W�IYe•�I;� I' ��6�.�
Buena Park - Palm Desert • Hemet
Sladden Engineering
450 Egan Avenue, Beaumont, CA 92223 (951) 845 -7743 Fax (951) 845 -8863
One Dimensional Consolidation
ASTM D2435 & D5333
Job Number: 544 -08277 December 31, 2008
Job Name: La Quinta Resort Expansion
Lab ID Number: LN6 -08713 Initial Dry Density, pef: 84.7
Sample TD: BH -2 #2 @ 5' Initial Moisture, %: 18.5
Soil Description: Olive Brown Sandy Silt (ML) Initial Void Ratio: 0.968
I
0
-1
-2
-3
r
ao
v
K
-5
U
-6
. -7
-8
-9
-10
Specific Gravity: 2.67
Hydrocollapse: 0.2% @ 0.702 ksf
"/e Change In Height vs Normal Presssure Diagram
0 Before Saturation —6 After Saturation
— 0 Rebound Hydro Consolidation
0.1 1.0 10.0
Normal Load (ksf)
Buena Park - Palm Desert - Hemet
100.0
Sladden Engineering
450 Egan Avenue, Beaumont, CA 92223 (951) 845 -7743 Fax (951) 845 -8863
One Dimensional Consolidation
ASTM D2435 & D5333 '
Job Number: 544 -08277 December 31, 2008
Job Name: La Quinta Resort Expansion
Lab ID Number: LN6 -68713 Initial Dry Density, pcf. ` 91.3
Sample ID: BH -3 #1 @ 5' Initial Moisture, %: 8.0
Soil Description: Yellow Brown Silty Sand (SM) Initial Void Ratio: 0.825
Specific Gravity: 2.67
Hydrocollapse: 0.3% @ 0.702 ksf
°/u Change in Height vs Normal Pressure Diagram
—A— Before Saturation 6 After Saturation
—0 Rebound f Hydro Consolidation
0.1
1.0 10.0
Normal Load (ksf)
Buena Park - Palm Desert • Hemet
100.0
1
0
-2
-3
d
x
-4
m
a
-5
U
°
-6
-7
-8
-10
0.1
1.0 10.0
Normal Load (ksf)
Buena Park - Palm Desert • Hemet
100.0
Sladden Engineering
450 Egan Avenue, Beaumont, CA 92223 (951) 845 -7743 Fax (951) 845 -8863
One Dimensional Consolidation
ASTM D2435 & D5333
Job Number: 544 -08277 December 31, 2008
Job Name: La Quinta Resort Expansion
Lab ID Number: LN6 -08713 Initial Dry Density, pcf: 88.9
Sample 1D: BH -4 #3 @10' Initial Moisture, %: 25.8
Soil Description: Olive Brown Sandy Silt (ML) Initial Void Ratio: 0.876
Specific Gravity: 2.67
% Change in Height vs Normal Presssure INagram
0 Before Saturation --6 —After Saturation
-- 9— Rebound --W—Hydro Consolidation
1 l
f
-2 ....... - --
-3 —
x -4_ I -
~ I I:
I -5
U
-7 --
-8 - --
-9 — - -
-t0
0.1 1.0 10.0
Normal Load (W)
Buena Park - Palm Desert • Hemet
100.0
Sladden Engineering
6782 Stanton Ave., Suite A, Buena Park, CA 90621 (714) 523 -0952 Fax (714) 523 -1369
77 -725 Enfield Lane Suite 100, Suite G, Palm Desert, CA 92211 (760) 772 -3893 Fax (760) 772 -3895
450 Egan Avenue, Beaumont, CA 92223 (951) 845 -7743 Fax (951) 845 -8863
Date: January 22, 2009 r
Account No.: 544 - 08277.
Customer: Pyramid Project Management LLC
Location: L.Q Resort Expansion Renov,49 -499 Eisenhower Dr, L.Q
Analytical Report
Corrosion Series
pH Soluble Sulfates Soluble Chloride Min. Resistivity
per CA 643 per CA 417 per CA 422 per CA 643
ppm ppm ohm-cm
BI 0 -5' 8,6 155 60 1,500
B2 @0 -5' 8.2 580 180 770
APPENDIX C
RETAINING WALLS - SEISMIC CONDITIONS
Sladden Engineering
i
DYNAMIC LATERAL LOADING - Vertical Wall wtth Level Backflll
H = 10 FEET co _ ®° YeV = 107 PCF Amax = 0.32 g
b = ®° Ka Kae =�
Pa = 1654 LBF /FT Pao = 3125 LBF /FT APae = 1475 LBF /FT
APae @ 0.6H
H R@ h'
ZI
Pa @ H/3
t
Id P = 330 PSF
DYNAMIC PRESSURE BEHIND WALL
SUMMARY
h'= FEET FROM WALL BASE
R = 3.13 KIP /FOOT
Mot = 14.3 KIP - FEET /FOOT
Pmin = 111 PSF
Pmax = 184 PSF
TOTAL PRESSURE FORCE
TOTALPRESSURE
111 PSF
R = 3.13 KIP /FOOT
514 PSF
Projcct No. 544 -08288 Sladden Engineering
Report No: 08 -12 -650
DYNAMIC LATERAL LOADING - Vertical Wall with Level Backfill
H = 15 FEET 4) = 30 Ye4 = 107 PCF Amax = 0.32 g
b = ®° Ka =FTST--1 Kee =�
Pa = 3713 LBF /FT Pao. = 7031 LBF /FT APae = 3318 LBF /FT
L
— APae @ 0.61-1
—R @ h'
Pa Q H/3
G:
P = 495 PSF
DYNAMIC PRESSURE BEHIND WALL
s
SUMMARY
h' =FEET FROM WALL BASE
R = 7.03 KIP /FOOT
Mot = 48.4 KIP - FEET /FOOT
TOTALPRESSURE
Pmin = 187 PSF
Pmax = 278 PSF
TOTAL PRESSURE FORCE
187 PSF
R = 7.03 KIP /FOOT
= 771 PSF
Project No. 544 -08288 Sladden Engineering Report No. 08 -12 -650
DYNAMIC LATERAL LOADING - Vertical Wan with Level Backflll
H = 20 FEET 4) = 30 Yeq = 107 PCF Amax = p 32 9
b - ®° Ka Kae =�
Pa = 6601 LBF /FT Pas = 12500 LBF /FT APae = 5899 LBF /FT
APae @ 0.6H h' =FEET FROM WALL BASE
H
R@ h' R= 12.50 KIP /FOOT
Pa @ H/3 Mot = 114.8 KIP - FEET /FOOT
t
P = 660 PSF
DYNAMIC PRESSURE BEHIND WALL .
Project No. 544 -08288
SUMMARY
Pmfn = 222 PSF
Pmax = 368 PSF
TOTAL PRESSURE FORCE
TOTALPRESSURE
222 PSF
R = 12.50 KIP /FOOT
1028 PSF
Report No. 08 -12 -650
Sladden Engineering
DYNAMIC LATERAL LOADING - Vertical Wall with Level Backfill
H = 25 FEET 0 _ ®° Yeq = 107 PCF Amax =F 0.32 g
b = ®° Ka Kae =�
Pa = 10314 LBF /FT Pae =F-1-95-327 LBF /FT AP- = 9217 LBF /FT
1l_
— APae @ 0.6H
R @ h'
Pa @ H/3
t
P = 825 PSF
DYNAMIC PRESSURE BEHIND WALL
SUMMARY
h'= 11. FEET FROM WALL BASE
R = 19.53 KIPWOOT
Mot = 224.1 KIP - FEET /FOOT
TOTALPRESSURE
Pmin = 278 PSF
i
Pmax = 459 PSF
TOTAL PRESSURE FORCE
278 PSF
R = 19.53 KIP /FOOT
1285 PSF
Project No. 544 -08288 Sladdcn Engineering Report No. 08 -12 -650
s
���aa
.,
0
Stantec
La Quinta Resort Redevelopment Project
Water Supply Assessment
Table of Contents
1.0 INTRODUCTION ..................................................................................... ..............................1
1.1
BACKGROUND ....................................................................................... ..............................1
1.2
PURPOSE OF DOCUMENT .................................................................... ..............................1
1.2.1 Water Supply Assessment (WSA) ............................................ ..............................1
1.3
PROJECT DESCRIPTION ....................................................................... ..............................1
1.3.1 Application of Water Supply Assessment ................................. ..............................2
1.4
PUBLIC WATER SUPPLY .................................:..................................... ..............................5
1.4.1 General ..................................................................................... ..............................5
1.4.2. Historical Context .................:.................................................... ..............................6
1.5
EXISTING WATER MANAGEMENT PLANS ........................................... ..............................7
1.5.1 Coachella Valley Water Management Plan .............................. ..............................7
1.5.2 Urban Water Management Plan ............................................... ..............................7
1.5.3 Additional Coachella Valley Water District Documentation ....... .......................:......8
2.0 WATER DEMANDS ........................ .... 9
2.1 PROJECT DEMANDS ..................... Dfa"'
.. ................................ ..............................9
......................:........ ............................... 2.1.1 Existing Water Demands ....... ..............................9
. .................... ...............................
2.1.2. Project- specific Water Demand Estimate ................................ ...........................:.10
2.2 WATER CONSERVATION MEASURES ................................................ .............................13
2.2.1 Desert Landscaping: Native and Other Drought - Tolerant Plants ..........................13
2.2.2 Project- Specific water Conservation and Groundwater Reduction Measures ......13
2.3 PROJECT WATER DEMAND AND CONSERVATION SUMMARY ....... ..................... .........14
3.0 WATER SUPPLY ASSESSMENT ( WSA) .. ...............................
3.1 GENERAL ................................................... ...............................
3.2 IDENTIFICATION OF WATER SOURCES . ...............................
3.2.1 Primary Water Sources ................ ...............................
3.2.2 Additional Water Sources ............ ...............................
3.3 ANALYSIS OF WATER SUPPLY ............... ...............................
3.3.1 Groundwater ................................ ...............................
3.3.2 Aquifer Adjudication .................... ...............................
3.3.3 Additional Water Sources ............ ...............................
3.3.4 Summary of Primary and Additional Water Sources...
3.4 ANALYSIS OF WATER SUPPLY AND DEMAND .....................
3.4.1 Normal Water Year Supply and Demand ....................
3.4.2 Single Dry Year Supply and Demand .........................
3.4.3 Multiple Dry Year Period Supply and Demand ...........
3.4.4 Summary ...................................... ...............................
3.5 CONCLUSIONS .......................................... ...............................
One Team. Infinite Solutions.
........................................ 15
.......... .............................15
.......... .............................15
.......... .............................15
.......... .............................15
.......... ..............:..............15
.......... .............................15
.......... .............................16
........ ............................... 20
........ ............................... 26
........ ............................... 27
........ ............................... 28
.......................... :............ 29
....................................... 30
.................. .................35
. ............................... ...36
Stantec
3.5.1 Coachella Valley Water District Service Area .......................... ......................:......36
3.5.2 Project Water Requirements ....:................. ............................... .............................
..........................36
4.0 LIST OF ACRONYMS ............................................................................ .............................37
5.0 SOURCES ....................................................:......................................... .............................38
6.0 REPORT PREPARERS ........................................................................... .............................39
APPENDIX A: Water Demand Projections for the Indio Trails Specific Plan
APPENDIX B: Water Resources Litigation and Other Actions (from the Panorama Specific
Plan Water Supply Assessment and Verification)
APPENDIX C: Coachella Valley Water District Technical Analysis of Regional Water
Supply and Demand (from the Panorama Specific Plan Water Supply Assessment and
Verification)
One Team. Infinite Solutions.
Stantec
LA QUINTA RESORT REDEVELOPMENT PROJECT
WATER SUPPLY ASSESSMENT
Executive Summary
Executive Summary
The La Quinta Resort Redevelopment Project is located in the City of La Quinta off Eisenhower
Drive, about one mile west of Washington Street. It is bounded by. Eisenhower Drive to the east,
Calle Mazatlan to the south and west, and Avenida Fernando to the north. The Project area is
approximately 66 acres, although only a small portion (approximately 26 acres) will be
redeveloped with new buildings and uses. The entire project area redevelopment results in a
combination of new and existing buildings that include: 1,512 hotel /villa units, 285,251 square
feet of commercial retail space, and 48 residential units..
Currently, the resort uses 361.9 acre -feet of water per year. Project - specific water demand
estimates, based on the application of conservation requirements of the CVWD Landscape
Ordinance 1302.1 'and the updated demand factors for new construction is projected to reduce
demand for the La Quinta Resort project to approximately 317.54 acre -feet per year. This
demand estimate represents 12% reduction in water use compared to similar development
throughout CVWD's service area. This reduction in demand is primarily due to the conservation
requirements in CVWD's Landscape Ordinance 1302.1, which requires reduced water
allowances for landscaped and recreatio al im. ft
The La Quinta Resort Specific Plan Amendment project ' is required to secure approval of a
Water Supply Assessment (Senate, Bill 610). In compliance with this legislated requirement, this
document examines the current condition of the Coachella Valley groundwater basin (aquifer)
and finds the water supply from the aquifer, the State Water Project (SWP), the Colorado River
and other sources adequate to supply the Project in accordance with California Water Code
Section 10910 et seq.
G
i..
�.
l��a 4
Stantec
LA QUINTA RESORT REDEVELOPMENT PROJECT
WATER SUPPLY ASSESSMENT
1.0 Introduction
1.1 BACKGROUND
c
The proposed La Quinta Resort Redevelopment Project (Project) includes the redevelopment of
a portion of the La Quinta Resort bounded by Eisenhower Drive to the east, Calle Mazatlan to
the south and west, and Avenida Fernando to the north; 25.9 acres of the 66.5 acres in
Planning Area 1 in the La Quinta Resort Specific Plan, Amendment 5, will be renovated.'A total
of 180 resort villas and 46,500 square feet of ancillary resort space will be demolished to
accommodate the new development. The.Project proposes to redevelop and expand the hotel
resort area in Planning Area 1 to construct 350 resort villas, 502 hotel units and 133,813 square
feet of tourist commercial uses. The redevelopment will result in a total of 1,513 resort villas and
hotel rooms, 260,938 square feet of commercial and ancillary hotel space, and 48 residential
condominium units within Planning Area 1. Since this Project is subject to the California
Environmental Quality Act (CEQA) process and is a "project" as defined by the California Water
Code Section 1.0912, the Coachella Valley Water District, the Public Water System (PWS) .for
the Project, has determined that a Water Supply Assessment (WSA) is necessary to complete
the Project's CEQA process.
1.2 PURPOSE OF DOCUMENT
Draft'.
Upon request of local government, a PWS is required by law to provide documentation
regarding the water supply for new projects. This information is included in the CEQA
documentation and it becomes evidence used in the approval process for the proposed
development.
1.2.1 . Water Supply Assessment (WSA)
Requirements for the preparation of a Water Supply Assessment are set forth in Senate Bill 610
(SB610) which was enacted in.2001 and became effective January 1, 2002. SB610 amended
Section 21151.9 of the Public Resources Code. SB 610 also amended Sections 10631., 10656,
10910, 10911, 10912, and 10915, repealed Section 10913, and added and amended Section
10657 of the California Water Code. It requires cities and counties to request specific
information on water supplies from the PWS that would serve any project that is subject to
CEQA and is defined as a "Project" in Water Code Section 10912. This information is to be
incorporated into the environmental review documents prepared pursuant to CEQA.
1.3 .. PROJECT DESCRIPTION
The Project is located south of Avenida Fernando and west of Eisenhower Drive within the city
limits of the City of La Quinta. The Project includes the redevelopment of approximately 25.9
acres within Planning Area 1 of the La Quinta . Resort Specific Plan, Amendment 5. For this
evaluation, the entire Planning Area 1 of the La Quinta Resort will be analyzed for current water.
1.
Stantec
LA QUINTA RESORT REDEVELOPMENT PROJECT
WATER SUPPLY ASSESSMENT
Introduction
February 27, 2009
use and potential future water use. The parcels for development are contained in Section 36,
Township 5 South, Range 6 East (SBBM). Figure 1 shows the location of the proposed project
in .relation to the surrounding street system. As mentioned above, the Project consists of
renovating and redeveloping approximately 25.9 acres of the La Quinta Resort. The proponent
wishes to redevelop the hotel and_ resort villas to include an additional 672 units, and expand the
commercial and ancillary hotel uses by 63,000 square feet, while keeping the residential portion
of Planning Area 1 as it is today. After the proposed redevelopment, Planning Area 1 will include
a total of 48 private residential units, 1,513 resort villas and hotel units, and 260,938 square feet
of commercial retail and ancillary hotel space. The summary of proposed land uses is shown in
Table 1 -1.
Table 1 -1 La Quinta Resort Redevelopment Specific Plan Land Uses
vI `.AI`
The other planning areas of the La Quinta Resort Specific Plan will remain as they currently
exist.
1.3.1 Application of Water Supply Assessment ,
State Water Code Section 10912 defines a "Project" as any of the following:
1) A proposed residential development of more than 500 dwelling units.
2) A proposed shopping center or business establishment employing more than 1,000 .
persons or having more than 500,000 square feet of floor space.
3) A proposed commercial office building employing more than 1,000 persons or having
more than 250,000 square feet of floor space.
4) A proposed hotel or motel, or both, having more than 500 rooms.
2
Land Use Description
Acres
Units
Estimated Commercial
Square Footage
Private
Medium Density
Residential
Residential
5.5
48
Hotel and
Commercial/
Tourist Commercial
61.0
1,513
260,938
Ancilla
Total
260,938
vI `.AI`
The other planning areas of the La Quinta Resort Specific Plan will remain as they currently
exist.
1.3.1 Application of Water Supply Assessment ,
State Water Code Section 10912 defines a "Project" as any of the following:
1) A proposed residential development of more than 500 dwelling units.
2) A proposed shopping center or business establishment employing more than 1,000 .
persons or having more than 500,000 square feet of floor space.
3) A proposed commercial office building employing more than 1,000 persons or having
more than 250,000 square feet of floor space.
4) A proposed hotel or motel, or both, having more than 500 rooms.
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Stantec
LA QUINTA RESORT REDEVELOPMENT PROJECT
WATER SUPPLY ASSESSMENT
Introduction
February 27; 2009
Stainiec - `
LA QUINTA RESORT REDEVELOPMENT PROJECT
WATER SUPPLY ASSESSMENT
Introduction
February 27, 2009
5) A proposed industrial, manufacturing, or processing plant, or industrial park planned
to house more than 1,000 persons, occupying more than 40 acres of land, or having 4
more than 650,000 square feet of floor area.
6) A mixed -use project that includes one or more of the projects specified in this,
subdivision.
7) A project that would demand an amount of water equivalent to, or greater than, the
amount of water required by a 500 dwelling unit project.
The proposed development is a "Project" as defined by Water Code Section 10912 and requires
a WSA because it proposes the construction of over 500 hotel rooms /villas.
1.4 PUBLIC WATER SUPPLY
1.4.1- General
CVWD is the PWS for the area in which the Project is located. CVWD provides services for ;
domestic water, irrigation water, sanitation'sewerage collection, wastewater reclamation and_ >
recycling, imported water, stormwater protection and agricultural drainage.
CVWD currently has approximately Droaftstic water connections and has a
groundwater production capacity of 243 million gallons per day (MGD). Areas served with
domestic water by. CVWD include a portion of lands near Desert Hot Springs, the Indio Hills
• . area and a portion of Cathedral City..CVWD serves all of Rancho Mirage, Thousand Palms,
Palm Desert, Indian Wells, La Quinta and a portion of Indio and Coachella. The District also
serves other rural communities, including Thermal, Mecca', Desert Shores, .Salton Sea Beach,
Salton City, North Shore, Bombay Beach and Hot Mineral Springs.
The CVWD service area encompasses roughly 637,000 acres, mostly within Riverside County,
but also extends into northern Imperial and San Diego Counties. The Coachella Valley is
bordered on the west and north by high mountains, which provide an effective barrier against
coastal storms, and which greatly reduce the contribution of direct precipitation to recharge the
valley's groundwater basin. The majority of natural recharge comes from runoff from the
adjacent mountains.
Development throughout the Coachella Valley has been dependent on groundwater as a source
of supply. The demand for groundwater has annually exceeded the limited natural recharge of
the groundwater basin. Therefore imported water is used to recharge the Aquifer and reduce.
groundwater overdraft.
5
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LA QUINTA RESORT REDEVELOPMENT PROJECT
WATER SUPPLY ASSESSMENT
Introduction
February 27, 2009
1.4.2 Historical Context
The need to enhance the public water supply in the Coachella Valley has been recognized for "
many years. The formation of CVWD in 1918 was a direct result of the concern of local
residents about a plan to export water from the Whitewater River to Imperial County. Early on,
valley residents also recognized that action was needed to stem the decline of the water table,
which was occurring as a result of local pumping in the east valley. As a result, CVWD entered
into an agreement for the construction of the Coachella Branch of the All American Branch:
Canal in order to bring Colorado River, water to the Coachella Valley. Since 1949, the Coachella
Branch Canal has been providing water for irrigation use in. the area that generally-
encompasses Indio and La Quinta southerly to the Salton Sea. Colorado River water is
delivered by an underground irrigation distribution piping system from the approximately 120
mile canal to farms and a growing number of golf courses in the Coachella Valley. In recent
years, CVWD has begun a program of recharging the Aquifer in the Lower Valley with this
source.
The need for additional water supplies was recognized due to the onset of development in the
western Coachella Valley, As a result, in 1963 CVWD and the Desert Water Agency (DWA),
which serves the Palm Springs area and a portion of Cathedral City, entered into separate
contracts with the State of California in er toe re that SWP water would be available. '
Because a direct pipeline from the SWP s r7 Coachella Valley does not exist, CVWD
and DWA entered into an exchange agreement with the Metropolitan Water District of Southern
California (MWD) to* receive water from the MWD Colorado River Aqueduct, which crosses the
upper portion of the Coachella Valley near Whitewater. In exchange, CVWD and DWA have
their. SWP water .delivered to MWD. Since 1973, CVWD and DWA have been receiving
Colorado River water from MWD's Colorado River Aqueduct turnout located at Whitewater
Canyon to replenish groundwater in the Coachella Valley.
In addition, CVWD has recognized the need to provide other sources of water to replenish the
Coachella Valley groundwater basin. CVWD has been recycling reclaimed wastewater since
1967 and operates six water reclamation plants, three of which currently recycle water.
Recycled water is currently used for 'golf course and greenbelt irrigation in the cities of Palm
Desert, Indian Wells and Indio, thereby reducing demand on groundwater in the basin.
CVWD has two groundwater recharge projects operating in the west side of the lower Coachella
Valley: one near Lake Cahuilla (Dike 4); and one on the Martinez Canyon alluvial fan. These,
facilities have recharged approximately 25,000 acre feet of Colorado River water since 1997
(from the Engineer's Report on Water Supply and Replenishment Assessment — Lower
Whitewater River Subbasin Area of Benefit 2007 - 2008," prepared by the Coachella Valley
Water District, April 2007).
6
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LA QUINTA RESORT REDEVELOPMENT PROJECT
WATER SUPPLY ASSESSMENT
Introduction
February 27, 2009 .
1.5 EXISTING WATER MANAGEMENT PLANS
1.5.1 Coachella Valley Water Management Plan
CVWD and other interested parties initiated a water management planning process in the early
.1990s to address.the overdraft conditions in the Aquifer and .to ensure that there would be
adequate water supplies in the future. The Coachella Valley Water Management Plan ( CVWMP)
is the product. of this planning process. The Board of Directors approved the CVWMP on
October 8, 2002. As part of the CVWMP planning process, a Program Environmental Impact
Report (PEIR) was prepared in accordance with CEQA guidelines. The PEIR was circulated
through the State Clearinghouse and to the public for extensive review. A Final PEIR was
certified for the CVWMP in September 2003.
The CVWMP adopted by CVWD is the comprehensive water resource management document
for the Coachella Valley that utilizes a conjunctive management approach that incorporates
conservation, additional sources of supply, and local resources.. The CVWMP is a
comprehensive water management plan that guides CVWD and other regional water purveyors
in their effort to ensure a long -term reliable supply of water resources throughout the Coachella
Valley.
The CVWMP identifies oseveral water c ns iftrn asures with the goal to reduce overall
water consumption by 7% by 2015, and Dr, water demand by 10% by 2010, with
the goal to maintain this level of reduction through 2035. These measures include water efficient .
landscaping and irrigation controls, water efficient plumbing, tiered or seasonal water pricing,
public information and education programs, alternative water supplies, water restrictive
municipal development policies, appointing a CVWD conservation coordinator, and refining the
maximum water allowance budgets for landscaped and recreational areas. The CVWMP
Preferred Alternative reduces reliance on groundwater sources by utilizing more Colorado River
water, SWP water and recycled water.
CVWD is currently in the process of updating the 2002 CVWMP, which is expected to be
completed -in late 2008. The updated plan will incorporate additional conservation measures,
and identify additional water sources to address population growth and potential reductions in
future SWP water reliability.
1.5.2 Urban Water Management Plan
CVWD completed an update of the Urban Water Management Plan (UWMP) in December
2005, as required under California Water Code, Division 6, Part 2.6.. Much of the data used in
the UWMP was based on information in the CVWMP. However, domestic water demand
projections and State Water Project (SWP) purchases and reliability were updated in the 2005
UWMP to reflect changes since 2002. It is important to note that projected water demand and
supply data and water conservation programs in the UWMP apply only to the CVWD service
area, while demand and supply data in the CVWMP apply to the entire Whitewater River
rl
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LA QUINTA RESORT REDEVELOPMENT PROJECT
WATER SUPPLY ASSESSMENT
Introduction
February 27, 2009
Subbasin (WWRSB). The UWMP was adopted by the CVWD Board on December 13, 2005.
Both the UWMP and the CVWMP are included in this WSA and WSV by reference.
A WSA is required to document the Project's planned future uses and to assess water demand
associated with water. Water Code Section 10910(c)(2) states that if demands from the
potential future growth were accounted for in the most recently adopted UWMP, the water
supplier may incorporate the requested information from the UWMP in preparing the WSA.
CVWD water demand projections contained in the UWMP and CVWMP take into account the
increased growth and increased intensity throughout their service area. The Project is within the
service area covered by the CVWMP, the CVWMP PEIR and the UWMP.
1.5.3 Additional Coachella Valley Water District Documentation
Additional documentation used for this WSA includes the CVWD Engineer's Reports on Water
Supply and. Replenishment Assessment for current water demand. These yearly reports are
completed for groundwater subbasins within CVWD's service area. These reports are required
by the State Water Code before CVWD can levy -and collect groundwater replenishment
assessments. These reports describe the condition of groundwater supplies, the need for
groundwater replenishment, identification of the area of benefit, water production within the
area, and replenishment assessments to levviied u water production.
The CVWD Water System Backup Fac s U' Itudy is updated about every two years
and provides the most up -to -date water demand factors by development type. This study
assesses all new development and redevelopment projects within the CVWD service area and
identifies water demand by development type, calculates facility costs, and establishes charges
to ensure domestic water availability for future development.
Another key document used in this WSA is CVWD's Landscape Ordinance 1302.1, which puts a
limit on the type of plant materials, plant density, and the maximum water allowed per acre of
landscaped area.
0
1 11
LA QUINTA RESORT REDEVELOPMENT PROJECT L.
WATER SUPPLY ASSESSMENT
Water Demands
February 27, 2009
2.0 Water Demands
2.1 PROJECT DEMANDS
2.1.1 Existing Water Demands
The Project planning area includes a total of approximately 66.5 acres. Since the site is
currently developed with existing uses, an audit of the current water usage on site was
conducted by providing the onsite water meter numbers to CVWD to get the two -year historical
Water usage. This will provide an actual water usage onsite to compare with the expected water
usage after the construction is complete. The following tables show existing land uses and
water usage by groups of buildings based on location and land use. The resort map is shown in
Figure 2 -1 and the Planning Area 1 Subareas are delineated and labeled.
Table 2 -1 Existing Land Uses, Planning Area 1
Subarea
Acreage
Resort it
Casita I
cillary Uses
uare feet
Private
Residential
A
40.61
661
21,996
48
B
9.03
-
34,474
-
C
11.00
84
141,468
-
D
5.86
96
-
-
TOTAL
66.5
841
197,938
48
9
Stantec
LA QUINTA RESORT REDEVELOPMENT PROJECT
WATER SUPPLY ASSESSMENT
Water Demands
February 27, 2009
Table 2 -2 Existing Water Demands
Land Use
Acreage
Proposed for
Demolition?
Demand Factor with 35%
Return Flows (ac—ft/ac/ r
Demand
ac -ft/ t)2
Demand
MGD
Private Residential
5.5
No
3.61
19.86
0.018
Casitas 101 - 150
No
80.54
0.072
Casitas 221 - 272
No
10.91
0.010
Casitas 301 — 357;
374 —389
No
24.11
0.022
Casitas 401 — 412
No
0.803
0.0007
Casitas 358 — 373;
414 — 455; 460 —
461;475;501 —536
Yes
37.34
0.033
Casitas 601 — 629;
646 —653
Yes
27.58
0.025
Casitas 630 — 645;
653 — 671; 701 —
778
No
12.91
0.012
Casitas 801 - 857
Yes
72.90
0.065
Casitas 858 — 899;
901 — 980; 1601 —
1697
No
38.81
0.035
Casitas 1701 —
1797; 1801 -1897;
1901 -1997
No
Do
rpft
11.24
0.010
Spa La Quinta
Yes
4.99
0.004
The Grove & Tennis
Yes
157
0.003
Hotel
No
15.74
0.014
Hotel — Commercial
Yes
0.58
0.0005
Landsca in
-
-
-
-
-
TOTAL
361.9
0.324.
'From updated water demand factors, personal communication, Megan Brown, CVWD.
2Historical demand for everything except Landscaping and the Private Residential was gathered from CVWD
records for the water meters at the resort. The demand amount shown is for 2008.
3The hotel demolition will result in the removal of the retail shops, the central plaza, and the service area. The
ballrooms, restaurants, hotel lobby, and some of the service areas will remain as part of the complex.
4The existing landscaping was evaluated by the landscape architect for current water use (see Appendix A).
However, the historical water use that was gathered by CVWD through the water meter numbers on site include
indoor and outdoor water use and have already been accounted for in the numbers provided above.
2.1.2 Project- specific Water Demand Estimate
As seen in Table 2 -2 above, approximately 180 'resort villas will be demolished in addition to
46,500 square feet of ancillary Hotel, spa, restaurant, and retail buildings in order to make way
for new hotel facilities. The existing buildings will be replaced by a new Wellness Center (7,500
square feet) with pool, 95 resort villas, 502 traditional hotel units, and 126,313 square feet of
commercial and ancillary hotel uses (such as expansions to the existing ballrooms, retail shops,
and additional restaurants). The following table summarizes the changes to the land uses
onsite.
10
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LA QUINTA RESORT REDEVELOPMENT PROJECT
WATER SUPPLY ASSESSMENT
Water Demands
February 27, 2009
Table 2 -3 Proposed Land Uses in Planning Area 1
Subarea
Acreage
Resort
Villas /Casitas
-Hotel
Rooms
Ancillary Uses
(square feet
Private
Residential
A
40.61
661
-
21,996
48
B
9.03
95
-
41,974
-
C
1 11.00
-
502
221,281
-
D
5.86
255
1 -
I -
--
TOTAL
66.5
1,011
1 502
1 285,251
48
In order to provide an accurate estimate of the Project water demand, a site- specific analysis
was completed (see Appendix A). Based on this analysis, it is estimated that the Project will use
approximately 0.284 MGD, or about 317.5 ac- ft/yr, as shown in Table 2 -2. The application of
CVWD Landscape Ordinance 1302.1 requirements in the hotel redevelopment plans yields
indoor water demands that are higher than the outdoor landscaping demands.
Table 2 -4 Projqaf peXiapter Demands
Land Use
OdWoOWOrl
Use (ac -ft/yr)
ndoor Water
Use (ac -ft/yr)
Total Annual
Demand
(ac-ft/ r
Total Daily
Demand
MGD
Residential
-
-
19.9
0.018
Existing Hotel Casitas2
179.32
179.32
0.160
New Hotel Casitas
20.275
20.275
0.018
Existing Hotel Resort/ Ancillary Facilities2
15.74
15.74
0.014
New Hotel Resort/ Ancillary Facilities
8.895
8.895
0.008
New Spa Wellness /Commercial
16.25
16.25
0.015
Existing lus New Landscaping
57.16
57.16
0.051
TOTAL
1 57.16
1 240.48
1 317.54
1 0.284
I ne residential area will not be redeveloped or disturbed In any way. Historical water demand factors from the
Water Systems Backup Facilities Charge Study (2006) were used here to approximate continued water use in
this area.
2The Existing Resort water demands were taken from the evaluation of existing water use in Table 2 -2. The
water use is not anticipated to change in these areas since they will remain as they are today.
The project - specific analysis demonstrates an approximately 12% reduction in water use as
compared to the existing Project demand .shown in Table 2 -2. This reduction in water demand
can be attributed to project design, the implementation of the CVWD Landscape Ordinance
1302.1, and modern water - efficient appliances. The Landscape Ordinance puts a limit on the
plant materials, plant density, and the maximum water allowed per acre:of landscaped area.
Also, the use of low -water landscaping has been applied throughout the Project and includes
the use of water efficient desert plants, boulders, and other landscaping features that require
little or no water. The use of modern development standards that limit indoor water consumption
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are also to be applied, including water conserving appliances, such as low flush toilets and, low-
flow showerheads and faucets.
The calculations for the Project - specific water demand in Table 2 -4 are broken down by outdoor
landscape demand and indoor demand. The following is a description of the methodology used
to make the Project - specific water demand calculations.
2.1.2.1 Outdoor Landscape Water Demand Methodology
Landscape water demand is based on calculated landscape coverage area for each type of land
use and is based upon the Project design standards. The water demand for Project landscaping
is based on CVWD's Landscape Ordinance 1302.1: Maximum Water Allowance (MWA) for
Zone 1. Adherence to the MWA requirements as outlined in the CVWD ordinance assures
compliance with CVWD water conservation goals and requirements.
A majority of the new landscaping for the Project is designated as "low- water" landscaping.
Some turf grass areas will be included in the design. All of the new landscape design will 'be
subject to the Landscape Ordinance 1302.1. However, some of the existing landscape will
remain as it is today.`
The landscape architect for the project, or �s , Inc., has calculated the current water
use based on existing landscaping, 'an ft the annual applied water use for the
landscape plans proposed for- the project. The figures in Appendix A show the types of
landscaping and the estimated annual applied water use calculations for the entire Planning
Area 1. The calculations show that the site currently uses approximately 2,829,000 cubic feet of
water per year for outdoor water use. With the changes to the site and the adherence of the new
landscape plans to the CVWD ordinance, the outdoor water use will reduce to 2,489,900 cubic
feet of water per year. This is a savings of 339,100 cubic feet of water or a 12% reduction in the
outdoor water use.
. 2.1.2.2 Indoor Water Demand Methodology
Potable water demand was calculated for all indoor uses based on estimates from the American
Water Works Association Research Foundation (AWWARF) (American Water 'Works
Association, 1999)..For the existing private residential land uses, the historical water demand
numbers were used from the Water Systems Backup Facilities Charge Study (2006, updated
2007).
The water demand from the villas was estimated by using the Annual Consumption Factor table
updated for 2007 and provided by CVWD (personal communication with Megan Brown, CVWD).
The demand factor for Apartments and Condominiums was used in order to more accurately
represent the demand. expected. The water demand from the proposed hotel rooms was
estimated using the demand factor for Hotels and Motels from the same table.
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For indoor potable demand for non - residential land uses, the water demand factors developed
for commercial and retail development types were used in order to estimate the water demand
from the spa, hotel ballrooms and ancillary facilities, and tennis court areas. As a result of these
estimates, a total of 240.48 ac- ft/year would be required to. meet potable water demand
throughout the Project area (existing and new development).
2.2 WATER CONSERVATION MEASURES
Over the past several years, CVWD has made significant efforts and progress in providing
private and public consumers of local water resources with information to help conserve these
resources through the use of drought tolerant desert plants and efficient irrigation systems. In
addition, the County's development code requires that developers implement water - efficient
landscaping in developments within the County.
The CVWMP identifies several water conservation measures with the goal of reducing urban
water demand by 10% by 2010 and maintaining this level of reduction through 2035. These
measures include water efficient landscaping and irrigation, water efficient plumbing and
appliances, tiered or seasonal water pricing, public information and education programs,
alternative water supplies, water restrictive municipal development policies, appointing a CVWD
conservation coordinator, and refining maxim water allowance for landscaped and
�
recreational areas. ra
Water conservation for the Project will be achieved through: 1) drip and other efficient irrigation,
2) intelligent irrigation controllers, and 3) native and non - native drought - tolerant planting
materials.
2.2.1 Desert Landscaping: Native and Other Drought- Tolerant Plants
The need for progressive water conservation and control of landscape maintenance costs has
also prompted the greater use of native and non - native drought - tolerant planting materials
within the Indio Trails Specific Plan area. The Coachella Valley and CVWD have been a leader
in the promotion of these desert landscape materials and design themes, most notably in
Landscape Ordinance 1302.1. As a result, thoughtful and conservative management and use of
water resources have guided development of this Project landscape plan.
2.2.2 Project- Specific water Conservation and Groundwater Reduction Measures
An Environmental Impact Report (EIR) is being prepared for the La Quinta Resort Specific Plan
Amendment No: 6, and a broad range of mitigation measures have been included in the EIR to
address the Project's potential impacts on water resources.
The Project shall be required to implement the following measures in order to assure the most
efficient use of water resources and to meet and maintain the CVWMP goals throughout the life
of the Project:
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• Drought- tolerant landscaping will be used as a means of reducing water consumption
Detailed landscape and irrigation improvement plans for the La Quinta Resort SP will be
reviewed and approved by the CVWD. for compliance with the CVWD Landscape
Ordinance 1302.1.
The Project will install low -flush toilets and low -flow showerheads and faucets in all new
construction, as required by Section 17921.3 of the Health and Safety Code, Title 201
California Administrative Code Section,1601(b), and applicable sections of Title 24 of the
State Code.
• The installation and maintenance of efficient on -site irrigation systems will minimize
.runoff and evaporation, and maximize effective watering of plant roots. Drip irrigation
and moisture detectors will be used to the greatest extent practicable to increase
irrigation efficiency.
2.3 PROJECT WATER DEMAND AND CONSERVATION SUMMARY
The Project area currently uses an average of 361.9 ac -ft/yr based on water meter readings for
the past two years. -The Project - specific water demand model estimates a total water demand of
317.54 ac -ft/yr based on the maximu ater allmiance requirements set forth in CVWD
Landscape Ordinance 1302.1 and dem d ii'r e som CVWD demand factors. As a result,
project demand estimates based on th a s rdinance 1302.1 requirements yield an
overall reduction_ of 12% when. compared to the current water usage onsite.
Implementation of the requirements from CVWD Landscape Ordinance 1302.1, in conjunction
with Project - specific mitigation measures, are expected to result in the new development within
the resort meeting or exceeding the water conservation goals outlined in the CVWMP.
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3.0 . Water Supply Assessment (WSA)
3.1 GENERAL
Having established that the CVWMP and UWMP are applicable to this Project, the next
requirement of a WSA is to identify and describe the water supply sources of the PWS that will
serve the Project. State Water Code Section 10910(d) requires a WSA to include: identification
of any existing water supply Table A amounts, water rights, or water service contracts relevant
to the identified water supply for the proposed Project; and a description of the quantities of
water received in prior years by the PWS. According to the. UWMP, the Aquifer and other
sources of supply are adequate for a single dry year and multiple dry years for a 20 -year period
(UWMP,. Section 8).
3.2 IDENTIFICATION OF WATER SOURCES
3.2.1 Primary Water Sources
The Project will utilize groundwater from theDe Aquifer for all water demands. Alternative sources
are unavailable to the development ion and elevation. A description and
assessment of the Aquifer is provided in o the Water Supply section below.
3.2.2 Additional Water Sources
In addition to Colorado River water and groundwater; CVWD and the Coachella Valley have
additional water sources, including imported State Water Project (SWP) water, recycled water
and a limited amount of surface water. These sources are described in the Analysis of Water
Supply section below. In the future, drainage water from the shallow, semi - perched groundwater
zone, which is collected by CVWD's drainage system, will be treated and used to meet non -
potable uses as described in the CVWMP.
3.3 ANALYSIS OF WATER SUPPLY
3.3.1 Groundwater
Since the early part of the 20th century, the Coachella Valley has been dependent primarily on
groundwater as a source of domestic water supply. Groundwater is also used to supply water
for crop irrigation, fish farms, duck clubs, golf courses, greenhouses, and industrial uses in the
Coachella Valley,
Water Code Section 10910 (f) requires additional information when a groundwater basin is cited
as the water supply source for a project. The additional information includes a description of the
basin, the rights of the PWS to use the basin, the overdraft status of the basin, any past or
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planned overdraft mitigation efforts, historical use of the basin by the PWS, projected use of the .
basin by the Project, and a sufficiency analysis of the basin that is to supply the Project.
` 3.3.1.1 Description of the Aquifer
The Aquifer can be described as a giant tilted bathtub full of sand, with the high end at the
northwest,edge of the Coachella Valley near the community of Whitewater and the low end at.
the Salton Sea. The Aquifer underlies the cities of Palm Springs, Cathedral City, Rancho
Mirage, Palm Desert, Indian Wells, La Quinta, Indio, and Coachella, and the unincorporated
communities of Thousand Palms, Thermal, Bermuda Dunes, Oasis and Mecca.
In 1964, DWR`estimated that the five subbasins that make up the Aquifer contained a total of
approximately 39.2 million ac -ft of water in the first 1,000 feet below the ground surface, much
of which originated from runoff from adjacent mountains. However, the amount of water in the
Aquifer has decreased over the years due to ,pumpage to serve urban, rural and agricultural
development in the Coachella Valley, which has withdrawn water from the Aquifer at a rate
faster than the natural rate of recharge.
•3.3.2. Aquifer Adjudication
The groundwater basin has not been ad laftcy VWD shares a common groundwater
source with other PWSs, including e DWA , the Mission Springs Water
9 ( )
District (MSWD), the City of Coachella, the City of Indio and the Myoma Dunes Mutual Water
Company. Other groundwater users include some individual residents, farmers, golf courses,
businesses, and commercial facilities. DWA and CVWD both 'operate groundwater
replenishment programs whereby groundwater pumpers (other than minimal pumpers) pay a
per acre -foot charge that is used to pay the cost of importing and recharging the Aquifer.
3.3.2.1 Overdraft Status of the Aquifer
California Department of Water Resources (DWR) Bulletin 108 published in 1964 is the most
current bulletin published by the DWR that characterizes the condition of the Aquifer as a whole.
In Bulletin 108, DWR notes that the amount of usable supply in the overdrafted Aquifer is
decreasing (CVWMP, p. 6 -2). The annual overdraft for the Coachella Valley is estimated to be
approximately 70,000 acre -ft/yr per year, with a cumulative overdraft of 5.1 million acre -ft from
1964 through 2006 (CVWD, 2007).
The overdraft condition of the Coachella Valley has caused groundwater levels to decrease in
portions of the Lower Valley (from La Quinta to the Salton Sea) and has raised concerns about
water quality degradation and land subsidence. In 2006, overdraft in the lower portion of the
Whitewater River Subbasin was 66,960 acre -ft, and the cumulative overdraft was 4.3 million
acre -ft (CVWD, 2007).
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Groundwater- levels in the Upper Valley (from Palm Springs to La Quinta) have also decreased
substantially, except in areas where artificial recharge has successfully raised water levels (i.e., "
adjacent to and down gradient of the Whitewater Spreading Facility). CVWD has also conducted
demonstration recharge programs (Dike 4 and Martinez Canyon Recharge Site) in the Lower
Valley that have successfully recharged the lower aquifer located below the clay layers that
create the semi - perched groundwater zone. There are areas near the edges of the Valley where
the aquitard is absent and direct recharge to the deeper aquifer is possible. These areas include
the vicinity of Dike .4 flood control dike .and the Martinez Canyon alluvial fan. CVWD is
purchasing the lands to construct full -scale recharge facilities to reduce the Lower Valley
overdraft. The second recharge site at Martinez Canyon has successfully recharged the Aquifer
since it began operating. in 2004; it too is expected to be expanded in the future. The CVWMP
identifies the total recharge goals for these facilities as 40,000 acre - ft/yr for each facility.
3.3.2.2 Overdraft Mitigation Efforts
Coachella Valley Water Management Plan
As outlined in Section 2.5, CVWD and other participants have developed the CVWMP to
comprehensively protect and augment the groundwater supply. The CVWMP Preferred
Alternative reduces reliance on groundwaltr sourc by utilizing more Colorado River water,
SWP water and recycled water. The C orcommends that source substitution and
conservation measures be implemente o reduce demands on the Aquifer. The goal of. the
CVWMP is to reduce the overall water demand by 7% by 2015 and urban water demand by
10% by 2010. These reduction levels will be maintained through the remainder of the planning
period. By 2035, water conservation is expected to reduce future projected demands by about
66,000 acre -ft/yr (CVWD, 2007). These minimum goals must be achieved to ensure that
additional water supplies will not be required. The updated CVMWP to be completed in late
2008 is expected to establish additional conservation measures and higher goals for reductions
in water consumption.
CVWD Landscape Ordinance
CVWD Landscape Ordinance 1302.1 requires a series of reduction methods, including
requirements that new developments install weather -based irrigation controllers that
automatically adjust water allocation. Additional requirements include setbacks of spray emitters
from impervious surfaces, as well as use of porous rock and gravel buffers between grass and
curbs to eliminate run -off onto streets. With the exception of turf, all landscaping, including
groundcover and shrubbery, must be irrigated•.with a drip system. Also, the maximum water
allowance for landscaped areas throughout the CVWD service area has been reduced. This
new .reduction goal requires that developers maximize the use of native and other drought
tolerant landscape materials, and to minimize use of more water - intensive landscape features,
including turf and fountains.
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Source Substitution is the delivery of an alternate source of water to users currently pumping
groundwater. The substitution of an alternate water source reduces groundwater extraction and
allows the groundwater to remain in.storage, thus reducing overdraft. Alternative sources of
water include: municipal recycled water from WRP -7, WRP -9, WRP -10 and the City of Palm
Springs Wastewater Treatment Plant; Colorado River water, desalinated agricultural drain
water, and re -use of water used in aquaculture:
Source substitution projects under the CVWMP Preferred Alternative include the following:
• Conversion of existing and future golf courses in the Lower Valley from groundwater to
Colorado River water;
Conversion of existing and future golf courses in the Upper Valley from groundwater to
recycled water;
• Conversion of existing and future golf courses in the Upper Valley from groundwater to
Colorado River Water via SWP Exchange water;
• Conversion of agricultural irrigation from. groundwater to Colorado River water, primarily
`- in the Oasis area; and'
• Conversion of some municipal u orat. Later to treated Colorado River water in '
D -1.
Examples of effective alternative source substitute efforts include the following:
• CVWD has a recycled water system that treats recycled water from three water
reclamatiori plants and delivers to golf courses, schools and open spaces for irrigation. It
is estimated that 8,073 ac -ft of recycled water was delivered. in 2006.
• CVWD has a 54 -inch diameter pipeline under construction to deliver Colorado River
r
water to the Mid - Valley area for use with CVWD's recycled water for golf course and
open space irrigation. This source substitution will reduce the pumping from the
groundwater basin for these uses.
• CVWD has secured rights to the Colorado River and participated in the construction of
the All- American Canal and the Coachella Branch of the All- American Canal. Beginning
in 1.934, CVWD contracted with the United States and the Bureau of Reclamation for the
construction of a distribution system to deliver Colorado River water to the farms in the
Lower Valley. This system delivered 245,894 acre -feet of Colorado River water in 2006,
and increased deliveries to 257,548 acre -feet in 2007.
• CVWD has recharged the Lower Valley with Colorado River water and is planning the
construction of two major recharge facilities that will expand the recharge program.
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7
;; • CVWD has secured rights to SWP water and negotiated exchange and advanced
delivery agreements with the Metropolitan Water District of Southern California (MWD)
to exchange CVWD's SWP water for MWD's Colorado River water source. The SWP
l' exchange water is used to recharge the Aquifer in the Upper Valley. This recharge
is program was started in 1972 and has replenished the Aquifer with over two million acre-
feet of water.
• CVWD plans to utilize treated agricultural drainage water for irrigation purposes. A
desalination pilot study was completed in 2007. A full -scale desalination facility will have
r a 10 MGD capacity that will produce approximately 11,000 ac -ft/yr (7.5 MGD) of
irrigation water.
• CVWD has worked with an aquaculture farm and developed water efficiency programs
that include water treatment and reuse.
Conservation Programs
CVWD is working with the cities in its service area to limit the amount of water that can be used
fo'r outdoor landscaping. As the result of the adoption of state -wide indoor water conservation
measures requiring low flush toilets, shq#kr and faW@it flow restrictors, and other devices,. the
amount of water used inside homes ha bt. i • ntly reduced. With the large number of
new homes constructed, these con at ams have reduced impacts of new
development on the Aquifer.
3.3.2.3 Historical Groundwater Use
.Both the CVWMP and CVWD's annual Engineers Reports on Water Supply and Replenishment
Assessment on Groundwater Basins review the historical use of groundwater in the Coachella
Valley. In 1936, groundwater use was 92,400 ac- ft/year and increased continually to about
,378,000 ac -ft/yr in 1999, and 403,000 ad -ft/yr in 2006. Groundwater use has increased steadily
to ' present use levels. In recent years, the demand for groundwater in the Coachella Valley has
annually'exceeded the limited natural recharge to the groundwater basin.
3.3.2.4 Groundwater Sufficiency Analysis
The CVWMP shows that total water demand from all uses in the Coachella Valley, including
agriculture, was 668,900 ac -ft/yr in 1999, is projected to increase to 723,800 ac -ft/yr by 2015,
and may reach 890,600 ac -ft/yr by 2035 (CVWD, 2002). Total water demand of the Project is
estimated to be 317.54 ac- ft/yr, which represents approximately 0.04% of the total anticipated
urban demand in the Coachella Valley through 2035..
The UWMP projects that urban water demand by all uses in the CVWD service area, excepting
agriculture, will increase to 570,504 ac -ft/yr by 2015 and 644,288 ac -ft/yr by 2030. The demands
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of the Project are projected to be 317.54 ac- ft/yr, this represents approximately 0.05% of the '
total anticipated demand in CVWD's service area through in 2030.
The proposed project will adhere to the goals of the CVWMP by incorporating conservation
programs such as efficient landscaping practices and use of low -water fixtures. In addition, the
Project will participate via the payment of a Supplemental Water Supply Charge (SWSC), which
will be used to offset costs associated with purchasing new water supplies and other activities to
reduce the overdraft. The SWSC is determined based on the historical water use by each type
of development and the cost of purchasing imported water. Through this charge and the
conservation methods outlined above, all Project impacts on the groundwater basin "are,' .
expected to be mitigated.
i .
With almost 30 million ac -ft of combined storage and the ongoing implementation of the
CVWMP, the Aquifer is sufficient to supply the Project and other present and anticipated needs
for normal year, as well as one or more multiple-dry years, over the next 20 years. The CVWMP
assumes continued growth in demand and sets forth how that growth will be served. The water
use and conservation measures of the Project will, meet and exceed the requirements of the
CVWMP, and will not negatively impact other developments in the area covered by the
CVWMP.
3.3.3 Additional Water Sources
Draft.
As stated in Section 4.2 of this report, groundwater provides the water supply for the Project and `
this WSA focuses on the adequacy of this source to supply sufficient amounts of water to meet
the water demands of this Project. Additional water sources are considered as a supplement to
groundwater in that they are used to recharge the Aquifer, .serve as a source substitution for
groundwater, or are used for irrigation.
3.3.3.1 Colorado River Water
The Coachella Canal is a branch of the All- American Canal, which brings Colorado River water
into the Imperial and Coachella Valleys. The service area for Colorado River water delivery
under CVWD contract with the U.S. Bureau of Reclamation is. defined as` Improvement District
No. 1 (ID -1). Under the 1931 California Seven Party Agreement, CVWD has water rights to
Colorado _River water as part of the first 3.85 million acre feet allocated to California. CVWD is in
the third priority position along with the Imperial Irrigation District. This priority is ahead of the
550,000 acre feet allocation to the Metropolitan Water District of Southern California, which has
the lowest priority of the California Seven parties.
However, California's Colorado River supply is protected by the 1968 Colorado River Basin
Project. Act, which provides that the Colorado River supplies to Arizona and Nevada after 1968
shall be reduced to zero before California will be reduced below 4.4 million acre -feet in any
year. Historically, CVWD has received approximately .330, 000 ac -ft/yr of Priority 3a Colorado
River water. This source of water is considered reliable through execution of the 2003
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Quantification Settlement Agreement (QSA) among some of the California Colorado River
contractors.
The QSA was entered into and between CVWD, Imperial Irrigation District (IID), Metropolitan
Water District (MWD), and the San Diego County Water Authority (SDCWA). The QSA
quantifies CVWD's Colorado River water rights for the next 75 years. Under the QSA, CVWD
will receive up to 459,000 ac -ft/yr of Colorado River water as shown in Table 3 -1.
Table 3 -1 CVWD Deliveries under the Quantification Settlement Agreement
Component
Ac-ft/ r
Base Allotment
330,000
1988 MWD /IID Approval Agreement
20,000
Coachella Canal Lining to SDCWA
- 26,000
To Miscellaneous /Indian PPRs
-3,000
IID /CVWD First Transfer
50,000
IID /CVWD Second Transfer
53,000
MWD SWP Transfer
35,000
Total Diversion at Imperial Dam
459,000
Less Conveyance Losses
- 15,000
Total Deliveries to CVW
444,000
Source: CVWD, Coachella Valley Water Management Plan, September 2002, p. 7 -11.
Assumed losses after completion of canal lining projects.
Water from the Coachella Canal provides a significant supply source for the Lower Valley. In
1999, the Coachella Canal supplied over 60 percent of the water used in the Lower Valley, but
provided less than one percent of the water supply to the Upper Valley. Most of the canal water
was used for crop irrigation in the Lower Valley. In 1995, CVWD began operating the Dike No. 4
pilot recharge facility in the. La Quinta area and has successfully demonstrated the efficacy of
this site to recharge the Aquifer. This facility was expanded in 1998. Pilot testing of the
groundwater recharge facilities at Martinez Canyon has also yielded positive results.
Future development and associated increases in water demand, as well as quality concerns,
are expected to increase use of Colorado River water for domestic purposes. Determining the
best way to treat this water in order to substitute for and .decrease the area's dependency on
groundwater is an important objective of the CVWMP. Long -term water management plans for
the Coachella Valley call for the treatment and distribution of as much as 32,000- acre -feet of
Colorado River water for domestic use annually (from a CVWD Press Release prepared by the
CVWD on October 16, 2007).
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3:3.3.2 State Water Project (SWP) Water
CVWD and DWA are SWP contractors for the Whitewater .River basin Aquifer. The SWP
includes 660 miles of aqueduct and conveyance facilities extending from Lake Oroville in the
north to Lake Perris in the south. The SWP has contracts to deliver 4.1 million ac -ft/yr to 29
contracting agencies. CVWD's original SWP water right (Table A amount) was 23,100 ac -ft/yr
and DWA's original SWP Table A amount was 38,100 ac -ft/yr -for a combined Table A amount
of 61,200 ac- ft/yr.
Ir 2004, CVWD purchased an additional 9,900 acre -feet per year of SWP water from the Tulare
Lake Basin Water Storage District, which brought CVWD's SWP allotment to 33,000 ac- ft/yr.
Ir addition, CVWD and DWA have also negotiated an exchange agreement with MWD for
100,000 ac -ft/yr of SWP Table A amount. MWD has permanently transferred 88,100 ac -ft/yr and
10,900 ac -ft/yr of its SWP Table A amounts to CVWD and DWA, respectively. This exchange
agreement increases the total SWP Table A amount for CVWD and DWA to 178,100 ac- ft/yr,
with CVWD's portion equal to 126,350 ac- ft/yr. This agreement provides that CVWD and DWA
generally receive this water from the SWP during wet years, which allows the two agencies to
recharge the groundwater basin and operate a conjunctive use program, storing water in wet
years and pumping the groundwater bas' dry yea
Ir- 2007, CVWD and DWA made a seco t �c aJ0tSWP water from the Tulare Lake Basin
Water Storage District. CVWD purchased 5,250 ac -ft/yr and DWA purchased 1,750 ac- ft/yr. This
water will be available in 2010.
Also in 2007, CVWD and DWA completed the transfer of 12,000 ac -ft/yr and 4,000 ac- ft/yr,
respectively, from the Berrenda Mesa Water District for a total Table A amount of 16,000 acft/yr,
.which will be available in 2010.
Therefore, the total SWP Table A amount for CVWD and DWA is 194,100 ac- ft/yr, with CVWD's
portion equal to 138,350 ac- ft/yr. The following table summarizes CVWD and DWA total
allocations of Table A SWP water to be delivered when available.
Table 3 -2 State Water Project Water Sources (ac -ft/yr)
'The amounts for the Tulare Lake Basin Transfer #2 and the Berrenda Mesa Transfer will not be available until the year 2010.
2.7
Original SWP'
Table A
Tulare
Lake Basin
Transfer #1
Tulare
Lake Basin
Transfer #2
Metropolitan
Water District
Transfer
Berrenda'
Mesa
Transfer'
Total
CVWD
23,100
9,900
5,250
88,100
12,000
138,350
DWA
38,100
1,750
11,900
4,000
55,750
Total
61,200
9,900
7,000
100,000
16,000
194,100
'The amounts for the Tulare Lake Basin Transfer #2 and the Berrenda Mesa Transfer will not be available until the year 2010.
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Neater purveyors make annual, requests to the DWR for water allocations and DWR makes an
irvtial SWP Table A allocation for planning purposes, typically in the last month before the next
water delivery year. Throughout the year, as additional information regarding water availability
becomes available to DWR, its allocation /delivery estimates are updated. The following table
outlines the historic reliability of SWP deliveries, including their initial and final allocations for the
past 20 years (1988 through 2007).
r
.I
Table 3 -3 Department of Water Resources
Table A Water Allocations 1988 -2007
r
4
Year
Initial Allocation
Final Allocation
1988.
100%
100%
1989
100%
100%
1990
100%
100%
1991
85%
30%
1992
20%
45%
1993
10%
100%
1994
50%
50%
1995
40%
100%
1996
or-0
100%
1997
0
100%
1998
40%
100%
1999
55%
100%
2000
50%
90%
2001
40%
39%
2002
20%
70%
2003
20%
90%
2004
35%
65%
2005
40%
90%
2006
55%
100%
2007
60%
60%
11AVERAGE
1 52%
81%
1 Source: State of California Department of Water Resources, Watr
Contract Branch within the State Water Project Analysis Office,
Notices to State Water Contractors, 1988 -2007.
As :i oted previously, CVWD and DWA do not directly receive SWP water. Rather, CVWD and
DWA have entered into an exchange agreement with MWD that allows MWD to take delivery of
CVWD and. DWA SWP Table A water. In exchange, MWD provides an equal amount of
Colorado River water that MWD transports through its Colorado River Aqueduct, Which crosses
the Coachella Valley near Whitewater. The exchange agreement allows for advanced delivery
and, storage of water, thereby providing better and more efficient water management. As a
resL,lt, water is not recharged in every year, but when SWP and exchange waters are available.
i
23
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LA QUINTA RESORT REDEVELOPMENT PROJECT
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F -bruary 27, 2009
The large storage capacity of the Aquifer and the large volume of water in storage allow CVWD
apd DWA to pump from the Aquifer for a number of years without recharging and to recharge
[a rge amounts of water to refill the Aquifer.when the water is available.
Faecent court rulings are having .an effect on SWP deliveries. In 2007, federal Judge Wanger
ruled that the Bureau of Reclamation Operating Criteria and Procedures (OCAP) for the federal
Central Valley Project and the Biological Opinion issued by the US Fish and Wildlife Service
were inadequate. The court ordered that a new OCAP and a new Biological Opinion be
prepared. Revised operating criteria and procedures are being required by the court to address
CVP operation impacts on the delta smelt, a federally listed species. The revised OCAP and BO
will be completed in late 2008. Until the revised documents are completed, CVP and SWP
pumping will be restricted. The initial DWR SWP allocations for 2008 projected state -wide
average delivery to be 35% of the Table A amounts (See Table 3 -3 for a comparison with other
years). This initial allocation, which has now been superceded, is a function of the water in
storage in the SWP reservoirs and is prepared early in the water year when the snow pack has
not been developed. See Appendix B regarding additional details on water resource litigation
and other actions.
D'JVR, issues the State Water Project Delivery Reliability Report every two years, with the 2007
draft version currently available for publiggNiewa an he final Version report due later in 2008.
This updated report accounts for imps s r d livery reliability associated with climate
change and recent federal litigation (see Appendix B . Based on. information from the draft DWR
Reliability Report, the average reliability of future SWP Table A deliveries through 2027 is
,2
projected to be 63.9 %. This percentage of allocations is based on computer modeling of the
state's watersheds, past hydrology adjusted for climate change, recent federal litigation, and the
condition on the river and reservoir systems.
In February 2008, the California Fish and Game Commission accepted the long fin smelt as a
candidate species for listing under the California Endangered Species Act (ESA). The longfin
smelt is a close relative to the delta smelt that lives in the San Francisco Bay -Delta and is
13
believed to be impacted by water exports from the San Joaquin River Delta. As a result, the
Commission adopted regulations meant to protect this 'species but that may impact the SWP
deliveries. Preliminary estimates of the possible impacts.of longfin smelt protection on SWP
deliveries are between 0 and. 400,000 acre feet per year..
In order to account for the potential water reductions associated with the protection of the
longfin smelt, the average SWP water reliability of future SWP Table A deliveries to the
Coachella Valley was further reduced by 10 %, resulting in a SWP reliability of 53.9 %. This
reliability was based on the modified 2007 SWP reliability projections by DWR as noted above.
As a result, this 53.9% reliability factor takes into account all recent water litigation as well as
potential variability associated with climate change.
24
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water Supply Assessment (WSA)
F:bruary 27, 2009
F
}
GVWD and DWA also plan to purchase additional water from the SWP when it becomes
mailable. Purchase of additional SWP water may involve purchases on the spot market, as well
as the purchase of additional long -term supplies of Table A water.
3:3.3.3 Surface Water
Surface water supplies come from several local rivers and streams, including the Whitewater
�iver, Snow Creek, Falls Creek and Chino Creek. In 1999, surface water supplied
approximately three percent of the total water supply to the Upper Valley to meet municipal
demand, and . none to the Lower Valley. Because surface water supplies are affected by
variations in annual precipitation, the annual supply.is highly variable. Since 1936, the estimated
iistorical surface water supply has ranged from approximately 4,000 to 9,000 ac- ft/yr.
13.3.4 Recycled Water
W, astewater that has been highly treated and disinfected can be reused for landscape irrigation
and other purposes; treated wastewater is not .suitable for potable use. Recycled wastewater
f ias historically been used for irrigation of golf courses and municipal landscaping in the
Coachella Valley. In addition, fish farm effluent is available in certain localized areas of the
Lower Valley and is being recycled for re , Teaftch CVWD operates six water treatment pla generate recycled irrigation water for
golf courses and large landscaped areas. The water reclamation plant nearest the Panorama
project is WRP-4, which is located about 1.5 miles southwest of the Project site.' WRP -4
became operational in 1986 and allows CVWD to serve communities from La Quinta to Mecca.
WRP -4 currently. does not recycle its effluent but it may in the future if the demand for recycled
virater increases.
3.3.3.5 Desalinated Drain Water
Iii 1997, CVWD filed an application with the State Water Resources Control Board to
e.ppropriate all waters in the Coachella Valley Stormwater Channel (CVSC) up to a maximum
fowrate of 150 CFS, which is drainage from lands irrigated in ID -1. The intent of the application
is to retain local control of these local water resources. Initial diversions must take place by
2013, building up to full diversion in 2063.
Wp to 11,000 acre - ft/yr of agricultural drain water may be desalted to a quality equivalent to
Colorado River water and delivered for agriculture and other irrigation use. As a result of this
Grogram, approximately 13.6 MGD of drain water would be diverted and filtered prior to
desalination. The desalination facility is planned to have a 10 MGD capacity that would produce
about 7.5 MGD of product water. Approximately 3.5 MGD of the flow would bypass desalination
and will be blended with the product water to produce the desired quality. Delivery of this water
would begin at a rate of approximately 4,000 acre -ft/yr and is projected to reach 11,000 acre-
Nyr in approximately fifteen years.
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LA QUINTA RESORT REDEVELOPMENT PROJECT
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Water Supply Assessment (WSA)
FiBbruary 27, 2009
3.3.3.6 Permanent Water Purchases
CVWD purchases Table A amounts from SWP contractors as they have become available and
rreet CVWD's needs. Additional purchases from the SWP and from others with water rights,
mainly in the Central Valley of California, will be evaluated as they become available to
determine whether they meet CVWD's needs. If they do, CVWD may purchase additional SWP.
water rights.
3.3.4 Summary of Primary and Additional Water Sources _
Table 3 -4 shows CVWD's existing water supply entitlements, rights and service contracts as
discussed above. In summary, the groundwater supply .represents the 39.2 - million- acre -feet
st.pply discussed in detail in Section 3.3.1, the Coachella Canal Colorado River Water
represents the third priority supply secured through the QSA discussed in Section 3.3.2.1, and
the SWP Exchange Water represents the Table A entitlement discussed in Section 3.3.2.2.
Table 3 -4 Existing CVWD Water Supply Table A Amounts, Water Rights and Water
Service Contracts
" . Supply
Existing
Entitlement
Right
Contract
Other
Ever
Supplies,
Utilized?
'ac -ft/ r
Groundwater
Unspecified
X
Yes
Coachella Canal.
459,0002
X
Yes
Colorado River Water
SWP Exchange Water
138,3504
X
Yes
uvwu snares a common groundwater source mat nas not been adjuciicated.
2 A quantified in the Quantification Settlement Agreement between HD, MWD, and CVWD, October 2003.
3Imported SWP Exchange Water is not used as a direct water supply source, but rather is used to recharge
groundwater supplies in the Coachella Valley.
Indudes Original Table A Amount, Tulare Agreement and MWD Agreement.
The UWMP projects that the percentage of water from each of the current water supply sources
will change significantly by 2035 relative to 2005 conditions. Table 3 -5 shows the actual water
supplies in 2005 as well as the projected water supplies from 2010 through 2030.
26
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LA QUINTA RESORT REDEVELOPMENT PROJECT
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February 27, 2009
Table 3 -5 Summary of Historical and Projected Average Water Supply (ac- ft/yr)
Year
Groundwater
Supply'
Colorado River
Water Su pl Y2
SWP Exchange
Water
Recycled
Water
Desalinated
Drain Water
Total
Supply
1995
66,600
285,929
45,214
11,100
-
408,843
1996
50,700
289,726
100,376
11,520
-
452,322
1997
52,400
281,179
83,407
12,550
-
429,536
1998
1 71,100
281,714
99,729
13,657
-
466,200
1999
53,800
282,021
70,446
13,397
-
419,664
2000
71,000
282,781
56,161
13,289
-
423,231
2001
73,000
272,741
3,242
12,923
-
361,906
2002
76,500.
280,845
26,912
13,289
-
397,546
2003
78,600
245,069
3,177
13,903
-
340,749
2004
1 73,400.
238,456
.16,167
14,831
-
342,854
2005
85,100
282,000
46,000
15,300
-
428,400
2010
106,700
318,000
53,335
23,100
4,000
505,135
2015
123,100
342,000
58,240
25,100
8,000
556,440
2020
123,700
379,000
55,302
26,500
8,000
592,502
2025 4
124,200
404,000
1 51,188
27,600
11,000
617,988
2030
123,200
429,000
1 49,289
28,300
11,000.
640,789
Source: "Coachella Valley Water District Urban Water Management Plan Final Report," prepared by the Coachella
Valley Water District, December 2005; however SWP Exchange Water amounts have been modified as noted below.
'CVWD share of net groundwater inflow to Whitewater and Mission Creek subbasins, shared with DWA Service Area
and private pumpers. r't
ZNet water deliveries to Coachella Valley, excludi c e e o ses.
4Anticipated average availability assuming Metro t calls back 50% of the time in dry years.
°Modified version of CVWD 2005 UWMP to account for advanced deliveries, DWR SWP 2007 Reliability Report, and
reductions associated with Longfin Smelt. See Table C -11 in Appendix C.
3.4 ANALYSIS OF WATER SUPPLY AND DEMAND
The available supplies and water demands for CVWD's service area were analyzed in the
UWMP to assess the region's ability to satisfy demands during three scenarios: a normal water
year; a single dry year;.and multiple dry years. The following discussion presents the supply -
demand balance for the various drought scenarios in the CVWD service area for the 25 -year
planning period from 2005 through 2030.
The proposed Project is estimated to build out by 2021. To provide a conservative estimate of
the proposed project's contribution to CVWD water demand, the proposed project is assumed to
build out in an 11 -year span between 2010 and 2021. Since there is existing development, the
existing water use will be replaced by new water uses. It was shown above that the new uses
will be lower than the existing uses. For purposes of analysis, anything prior to 2021 was
analyzed using the current water Usage onsite, and anything subsequent to 2021 was analyzed
using the future expected water usage onsite.
Table 3 -6 below illustrates the assumptions associated with projected supply reliability by
source and is used in the following discussion of CVWD water supply and demand scenarios as
they relate to the Project.
27
Supply So. urces
Normal
Water Year
Single
Dry Year
Multiple Dry Years
Year 1
Year 2
Year 3
Groundwater
100%
100%
100%
100%
100%
Colorado River Water
100%
100%
100%
100%
100%
Recycled Water
100%
100%
100%
100%
100%
SWP Water
53.9%
6%
26%
26%
26%
Desalinated Drain Water
100%
100%
100%
100%
100%
Source: "Coachella Valley Water District Urban Water Management Plan Final Report," Table 3 -16,
prepared by the Coachella Valley Water District, December 2005; however, SWP Exchange Water
amounts have been modified as noted below.
'See Appendix C to this Water Supply Assessment: "Technical Analysis of Regional Water Supply and
Demand in the Coachella Valley Water District," prepared by Terra Nova Planning and Research, March
13, 2008.
3.4.1 Normal Water Year Supply and Demand
Table 3 -7 sets forth the projected water ufand for the CVWD service area during
normal water years through 2030. This I ed on an average SWP water reliability
delivery factor of 53.9 %, which is based on the modified 2007 SWP reliability projections by-
DWR. This 53.9% reliability factor takes into account recent water litigation, including the 2007
Wanger Decision, the listing of the longfin smelt as a candidate species under the California -
.Endangered Species Act, as well as potential variability in the hydrologic cycle associated with
climate change. It is important to note CVWD has- increased its total available SWP water
allocation since the 2005 UWMP was published; this has been accomplished through water
purchases and transfers. Under this.scenario, the total water demand for the Project represents
0.06% of CVWD's projected total demand in 2015; the Project's contribution to total demand
falls to 0.05% in 2030. As a portion of CVWD's total projected domestic water demand, the
Project's potable water demand represents 0.19% of CVWD total domestic water demand in
2015 and drops to 0.14% in 2030.
As shown in the following table; there are sufficient water - supplies in normal water years to
meet the projected demands while providing surplus water for groundwater recharge. A portion
of the normal year demand is met from groundwater storage in 2010- and. 2015, while storage
increases in subsequent years with CVMWP groundwater recharge activities, additional water.
conservation, drain water desalting and source substitution activities. In addition, it is believed
that over the long term, DWR will take action to reduce any impacts on the delta smelt, and,
longfin smelt and thereby increase the reliability factor for the SWP deliveries..
28
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LA QUINTA RESORT REDEVELOPMENT PROJECT
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Water Supply Assessment (WSA)
February 27, 2009
Table 3 -7 Normal Water Years 2010 -2030 (ac -ft/yr)
Supply Sources
2010
2015
2020
2025
2030
Groundwater
106,700
123,100
123,700
124,200
123,200
Colorado River Water
318,000
342,000
379,000
404,000
429,000
SWP Exchange Water
53,335
58,240
55,302
51,188
49,289
Recycled Water
23,100
25,100
26,500
27,600
28,300
Desalinated Drain Water
4,000
8,000
8,000
11,000
11,000
TOTAL SUPPLY
505,135
556,440
592,502
617,988
640,789
Demand
Domestic Water (including conservation
167,681
189,405
207,028
220,866
231,088
Golf Courses and Municipal Non-potable
67,200
90,100
90,100
90,100
92,400
Agriculture
283,500
291,000
291,600
314,600
320,800
TOTAL DEMAND '
518,381
570,505
588,728
'625,566
644,288
Supply vs. Demand
GROUNDWATER STORAGE
- 13,246
- 14,065
3,774
-7,578
-3,499
Source: - Coachella valley Water District Urban Water Management Plan Final Keport,- Tables a -1 and 8 -2, prepared
by the Coachella Valley Water District, December 2005; however, SWP Exchange Water amounts have been
modified as noted below.
'Modified version of CVWD 2005 UWMP to account for advanced deliveries, DWR SWP 2007 Reliability Report, and
reductions associated with Longfin Smelt. See Table C -11 in Appendix C.
3.4.2 Single Dry Year Supply and Dffqn
eft
The water supplies and demands for the D service area through 2030 were analyzed for a
20 -year period that includes a single dry year. The dry year considered is comparable to the
drought that occurred during 1977. Table 3 -8 presents the supply and demand, and compares .
the two during a single dry year. As shown in the supply and demand comparison table, total
supply will meet demand projections. In dry years CVWD would extract additional needed
supplies from groundwater in storage to meet total. demand projections. This temporary over -
extraction replaces SWP supplies that are assumed diverted to MWD in dry years. This would
occur with the understanding that the amount of over extracted groundwater would be
replenished in the future during wet years. This is the conjunctive use program that CVWD and
DWA have been managing for the last 30 years, is a key element of their groundwater
management program, and that includes the exchange agreements with MWD. The reduced
SWP deliveries during single dry years provide adequate water to recharge the basin as part of
a conjunctive use program.
Under the single dry year scenario, the total water demand for the Project represents 0.06% of
CVWD's total projected demand in 2015 and ,falls to 0.05% in 2030. As a portion of CVWD's
total projected domestic water demand, the Project's potable water demand represents 0.18%
in 2015 and drops to 0.13% in 2030.
29
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LA QUINTA RESORT REDEVELOPMENT PROJECT
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Water Supply Assessment (WSA)
February 27, 2009
Table 3 -8 Single Dry Water Years 2010 -2030 (ac -ft/yr)
Supply Sources
2010
2015
2020
2025
2030
Groundwater
106,700
123,100
123,700
124,200
123,200
Colorado River Water
318,000
342,000
379,000
404,000
429,000
SWP Exchan a Water
3,179
3,681
3,721
3,681
3,591
Recycled Water
23,100
25,100
26,500
27,600
28,300
Desalinated Drain Water
4,000
8,000
8,000
11,000
11,000
TOTAL SUPPLY
454,979
501,881
540,921
570,481
595,091
Demand.
Domestic Water (including conservation
175,562
198,307
216,759
231,247
241,949
Golf Courses and Municipal Non-potable
70,358
94,335
94,335
94,335
96,743
Agriculture
296,825
304,677
305,305
329,386
335,878
TOTAL DEMAND
542,745
597,319
616,399
654,968
674,570
Supply vs. Demand
GROUNDWATER STORAGE
- 8.7,766
- 95,438
- 75,478
- 84,487
- 79,479
Source: "Coachella Valley Water District Urban Water Management Plan Final Report," Tables 8 -4 and 8 -5, prepared
by "the Coachella Valley Water District, December 2005; however, SWP Exchange Water amounts have been
modified as noted below.
'Modified version of CVWD 2005 UWMP to account for advanced deliveries, DWR SWP 2007 Reliability Report, and
reductions associated with Longfin Smelt. See Table C -13 in Appendix C.
Note: CVWD operates under a conjunctive use program that allows it to provide additional water during wet years
that allows for excess water to be stored in the basin for use durin tdry years.
3.4.3 Multiple Dry Year Period Suppnl rid
The water supplies and demands for the CVWD service area through 2030 were analyzed in the
event that a multiple dry year drought event (similar to the drought that occurred from 1990
through 1992) was to occur. During a multiple dry year event, CVWD would meet all demand
projections through the extraction of additional needed supplies from groundwater in storage.
This temporary over - extraction replaces all reductions in supply, and would occur with the
understanding that the amount of over- extracted groundwater would be replenished in the
future, during wet years.
Table 3 -9 sets forth the supply and demand scenario and compares these two during a multiple
dry year event occurring between 2007 and 2011. Under the assumptions for the project
buildout scenario described above, the existing development's water use will be assumed to
exist through 2021, and the new development's water use will be assumed to exist after that
time. Under this assumption, the water demand for the Project in 2011 represents 0.070/0 of
CVWD's total projected demand in 2011. As a portion of CVWD's total projected domestic water
demand the Project's potable water demand represents 0.21% in 2011.
ca
; iI �
LA QUINTA RESORT REDEVELOPMENT PROJECT
WATER SUPPLY ASSESSMENT
Water Supply Assessment (WSA)
February 27, 2009
Table 3 -9 Multiple Dry Water Years 2007 -2011 (ac -ft/yr)
Supply Sources
2007
2008
2009
2010
2011
Groundwater
91,800
99,400
102,700
106,700
112,900
Colorado River Water
306,000
310,000
314,000
318,000
322,000
SWP Exchange Water
41,523
25,460
26,095
35,351
54,393
Recycled Water
17,900
19,200
20,500
23,100
- 23,500
Desalinated Drain.Water
0
0
0
4,000
4,000
TOTAL SUPPLY
457,223
454,060
463,295
487,151
517,593
Demand
20072
2008
2009
2010
2011
Domestic Water (including conservation
152,492
164,960
170,261
175,562
172,026
Golf Courses and Municipal Non-potable
48,360
57,208
63,783
70,358
71,780
Agriculture
277,920
292,930
294,877
296,825
285,000
TOTAL DEMAND
478,772
515,098
528,921
542,745
528,806
Supply vs. Demand
GROUNDWATER STORAGE
- 21,549
- 61,038
- 65,626
- 55,594
- 11,213
Source: - GOacnella Valley Water Vistrlct Urban Water Management Plan Final Report," Tables 8 -7 and 8 -8, prepared
by the Coachella Valley Water District, December 2005; however, SWP Exchange Water amounts have been
modified as noted below.
'Modified version of CVWD 2005 UWMP to account for advanced deliveries, DWR SWP 2007 Reliability Report, and
reductions associated with Longfin Smelt. See Table C -15 in Appendix C.
2Normal years (2007 and 2011) modified to account for 4.7% increased demand during dry years. This percentage is
applied as in the CVWD 2005 UWMP to increase demand during dry years (over normal years). See Table C -15 in
Appendix C.
Note: CVWD operates under a conjunctive use pry gr rh it to provide additional water during wet years
that allows for excess water to be stored in the ba or n g ry years.
31
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LA QUINTA RESORT REDEVELOPMENT PROJECT
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Water-Supply Assessment (WSA)
February 27, 2009
Table 3 -10 sets forth the multiple dry year supply and demand scenario, and compares supply
and demand during a multiple dry year event occurring between 2011 and 2015. The project
would still be building out and we would expect . the existing water use to still be in effect. Under
this assumption, the total water demand for the Project represents 0.07% of CVWD's total
projected demand in 2011 and 0.06% in 2015. As a portion of CVWD's total projected domestic
water demand, the Project's potable water demand represents 0.21 % in 2011 and decreases to
0.19% in 2015.
Table 3 -10 Multiple Dry Water Years 2011 -2015 (ac -ftlyr)
Supply Sources
2011
2012
2013
2014
2015
Groundwater
112,900
114,500
115,600
121,100
123,100
Colorado River Water
322,000
327;000
332,000
337,000
342,000
SWP Exchange Water
54,393
36,737
37,392
38,022
58,240
Recycled Water
23,500
23,900
24,300
24,700
25,100
Desalinated Drain Water
4,800
5,600
6,400
7,200
8,000
TOTAL SUPPLY
517,593
507,737
515,692
528,022
556,440
Demand.
Domestic Water (including conservation
172,026
184,660
189,209
193,758
189,405
Golf Courses and Municipal Non-potable
71,780
1 79,949
84,744
89,539
90,100
Agriculture
285,000
299,966
301,536
303,107
291,000
TOTAL DEMAND
0
4,575
575,489
586,404
570,505
Supply vs. Demand
k,838
GROUNDWATER STORAGE
-1 1,2ff
- 59,797
- 58,382
- 14,065
Source: "Coachella Valley Water District Urban .Water Management Plan Final Report," Tables 8 -10 and 8 -11,
prepared by the Coachella Valley Water District, December 2005; however, SWP Exchange Water amounts have
been modified as noted below.
'Modified version of CVWD 2005 UWMP to account for advanced deliveries, DWR SWP 2007 Reliability Report, and
reductions associated with Longfin Smelt. See Table C -19 in Appendix C.
Note: CVWD operates under a conjunctive use program that allows it to provide additional water during wet years
that allows for excess water to be stored in the basin for use during dry years.
Stahl K
LA QUINTA RESORT REDEVELOPMENT PROJECT
WATER SUPPLY ASSESSMENT
Water Supply Assessment (WSA)
February 27, 2009
Table 3 -11 sets forth the water supply and demand, and compares supply and demand during a
multiple dry event between 2016 and 2020. During this multiple dry year event the total water
demand (still the existing demand) from the project represents 0.06% of CVWD's total projected
demand in 2016 and in 2020. As a portion of CVWD's total projected domestic water demand,
the Project's potable water demand represents 0.19% in 2016 and drops to 0.17% in 2020.
{ Table 3 -11 Multiple Water Years 2016 -2020 (ac- ft/yr)
Supply Sources
2016
2017
2018
2019
2020
Groundwater
123,300
123,300
123,400
123,600
123,700
Colorado River Water
347,000
351,000
369,000
374,000
379,000
SWP Exchange Water
57,659
37,863
37,479
37,092
55,302
Recycled Water
25,380
25,660
25,940
26,220
26,500
Desalinated Drain Water
8,000
8,000
8,000
8,000
8,000
TOTAL SUPPLY
561,339
545,823
563,819
568,912
592,502
Demand
Domestic Water (including conservation
192,930
205,688
209,378
213,068
207,028
Golf Courses and Municipal Non- otable
0
4,335
94,335
94,335
90,100
Agriculture
9
04,928
305,054
305,180
291,600
TOTAL DEMAND
F57%,
4,951
608,767
612,767
588,728
Su I vs. Demand
GROUNDWATER STORAGE
2,811
- 59,128
- 44,948
- 43,671
3,774
Source: "Coachella Valley Water District Urban Water Management Plan Final Report," Tables 8 -13 and 8 -14,
prepared by the Coachella Valley Water District, December 2005, however, SWP Exchange Water amounts have
been modified as noted below.
'Modified version of CVWD 2005 UWMP to account for advanced deliveries, DWR SWP 2007 Reliability Report, and
reductions associated with Longfin Smelt. See Table C -19 in Appendix C.
Note: CVWD operates under a conjunctive use program that allows it to provide additional water during wet years
that allows for excess water to be stored in the basin for use during dry years.
33
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L4 QUINTA RESORT REDEVELOPMENT PROJECT
WATER SUPPLY ASSESSMENT.
Water Supply Assessment (WSA)
February 27, 2009
4
Table 3 -12 presents the supply and demand, and the comparison between these two during a
multiple dry year event occurring between 2021 and 2025. During this multiple dry year event,
the total water demand for the. project represents 0.05% of CVWD's total projected demand in
2b21 and is 0.05% in 2025. As a portion of CVWD's total projected domestic water demand, the
Project's potable water demand represents 0.15% in 2021 and drops to 0.14% in 2025.
Table 3 -12 Multiple Dry Water Years 2021 -2025 (ac -ft/yr)
Supply Sources
2021
2022
2023
2024
2025
Groundwater
123,200
123,200
124,200
124,400
124,200
Colorado River Water
384,000
389,000
394,000
399,000
404,000
SWP Exchange Water
54,473
35,617
35,077
34,538
51,188
Recycled Water
26,720
26,940
27,160
27,380
27,600
Desalinated Drain Water
8,600
9,200
9,800
10,400
11,000
TOTAL SUPPLY
596,993
583,957
590,237
595,518
617,988
Demand
Domestic Water (including conservation
209,796
222,554
225,452
228,349
220,866
Golf Courses and Municipal Non-potable
,335
94,335
94,335
90,100
Agriculture
4,938
319,754
324,570
314,600
TOTAL DEMAND
596,096
631,827
639,541
1 647,254
625,566
Supply vs. Demand
GROUNDWATER STORAGE
897
- 47,870
- 49,304
1 - 51,736
-7,578
Stiurce: "Coachella Valley Water District Urban Water Management Plan Final Report," Tables 8 -16 and 8 -17,
piepared by the Coachella Valley Water District, December 2005; however, SWP Exchange Water amounts have
been modifted'as noted below.
'Modified version of CVWD 2005 UWMP to account for advanced deliveries, DWR SWP 2007 Reliability Report, and
reductions associated with Longfin Smelt. See Table C -19 in Appendix C.
Note: CVWD operates under a conjunctive use program that allows it to provide additional water during wet years
tt;at allows for excess water to be stored in the basin for use during dry years.
i
ie
i
F
1
LA QUINTA RESORT REDEVELOPMENT PROJECT
WATER SUPPLY ASSESSMENT
Water Supply Assessment (WSA)
February 27, 2009
Table 3 -13 presents the supply and demand projections and the comparison of supply and
demand during a multiple dry year event between 2023 and 2027. During this multiple dry year
event, the total water demand for the Project represents 0.05% of .CVWD's total projected
demand in 2023 through 2027. As a portion of CVWD's total projected domestic water demand,
the Project's potable water demand represents 0.15% in 2023 and drops to 0.14% in 2027.
Table 3 -13 Multiple Water Years 2023 -2027 (ac -ft/yr)
Supply Sources
2023
2024
2025
2026
2027
Groundwater
124,200
124,200
124,200
123,700
123,200
Colorado River Water
394,000
399,000
404,000
409,000
414,000
SWP Exchange Water
52,825
35,617
35,077
34,538
49,289
Recycled Water
27,160
27,380
27,600
27,740
27,880
Desalinated Drain Water
9,800
10,400
11,000
11,000
11,000
TOTAL SUPPLY
607,985
596,597
601,877
605,978
625,369
Demand
20232
2024
2025
2026
2027
Domestic Water (including conservation
215,331
228,349
231,247
233,388
224,955
Golf Courses and Municipal Non-potable
90,100
94,335
94,335
94,816
91,020
Agriculture
305,400
324,570
329,386
330,684
317,080
TOTAL DEMAND
610,831
647,254
654,968
658,888
633,055
Supply vs. Demand
GROUNDWATER STORAGE
8
0,657
- 53,091
- 52,910
-7,686
Source: "Coachella Valley Water District Urban Water Management Plan Final Report," Tables 8 -19 and 8 -20,
prepared by the Coachella Valley Water District, December 2005; however, SWP Exchange Water amounts have
been modified as noted below.
'Modified version of CVWD 2005 UWMP to account for advanced deliveries, DWR SWP 2007 Reliability Report, and
reductions associated with Longfin Smelt. See Table C -25 in Appendix C.
2Normal years (2023 and 2007) modified to account for 4.7% increased demand during dry years. This percentage is
applied as in the CVWD 2005 UWMP to increase demand during dry years (over normal years). See Table C -25 in
Appendix C.
Note: CVWD operates under a conjunctive use program that allows it to provide additional water during wet years
that allows for excess water to be stored in the basin for use during dry years.
3.4.4 Summary
Projected water demand associated with the Project represents less than 0.1% of the total
CVWD water demand over the next 20 years. This project has the added uniqueness in that
although there will be new buildings and a rearranging of the land uses onsite, these new
buildings will replace and renovate existing buildings and improve the water efficiency of these
areas of the resort. This amounts to a water savings of 44.36 ac- ft/yr. In addition, the water
demand for the Project will account for only a small fraction of the total CVWD projected.
demands.
The 2005 UWMP indicated an average of 7,000 ac -ft/yr of aquifer replenishment for the period
2010 through 2030. This compares to a 7,000 ac -ft/yr reduction of aquifer storage under the
revised supply projections adjusted for SWP reliability reductions. This results in a very modest
35
Stantec
f.
LA QUINTA RESORT REDEVELOPMENT PROJECT
WATER SUPPLY ASSESSMENT
Water Supply Assessment (WSA)
February 27, 2009
reduction in ,aquifer storage that will be further addressed through additional water supply
purchases, water conservation, and source substitution.
3.5 CONCLUSIONS
3.5.1 Coachella Valley Water District Service Area
Based on the information, analysis, and findings documented in this WSA there is substantial
evidence to support a, determination that there will be sufficient water supplies to meet the
demands of the Project. This is based'on the volume of water available in the Aquifer, CVWD's
Colorado River contract supply, SWP Table A amounts, and rights and contracts to meet future -
demand as needed over time. CVWD has committed sufficient resources to further implement
the primary elements of the CVWMP, which include the purchase of additional water supplies,
water conservation, and source substitution.
3.5.2 Project Water Requirements
As shown in this WSA analysis, the projected demand for this Project will account for only a
small fraction of the total projected demands set forth in the CVWMP for the current period
through 2035, and the total projected de ds for C 'D UWMP through 2030.
1 P 41 , �/ q s
The Projects ecific water demand is 3 a hich is based on the requirements set
forth in. CVWD Landscape Ordinance 1302.1. As a result, the Project's demand estimates yield
an overall reduction of 12% when compared to the current water consumption at the resort.
Stanfiec
LA QUINTA RESORT REDEVELOPMENT PROJECT
WATER SUPPLY ASSESSMENT
List of Acronyms
February 27, 2009
4.0 List of Acronyms
AC -FT Acre Feet
AC -FT/YR Acre -Feet per Year
CEQA California Environmental Quality Act
CFS Cubic Feet per Second
CVSC Coachella Valley Stormwater Channel
CVWD Coachella Valley Water District
CVWMP Coachella Valley Water Management Plan
DWA Desert Water Agency
DWR California Department of Water Reg@Wces
ID -1 CVWD s Improvement District No. 1
raft
IID Imperial Irrigation District
MGD Million Gallons per Day
MWD Metropolitan Water District of Southern California
QSA Quantification Settlement Agreement '
SDCWA San Diego County Water Authority
SWSC Supplemental Water Supply Charge
SWP State Water Project :
UWMP Urban Water Management Plan
WSA Water Supply Assessment
WSV Water Supply Verification
WRP Water Reclamation Plant
37
Stantec
LA QUINTA RESORT REDEVELOPMENT PROJECT
WATER SUPPLY ASSESSMENT
Sources
February 27; 2009 ..
5.0 Sources
"Commercial and Industrial End Users of Water, Project #241 B, ". prepared by the American
Water Works Association, Summer 2000.
"Coachella Valley Final Water Management Plan," prepared by the Coachella Valley Water
District, September 2002.
"Coachella Valley Water District Urban Water Management Plan Final Report," prepared by the
Coachella Valley Water District, December 2005.
"Colorado River Interim Surplus Criteria, Final Environmental Impact Statement," prepared by-
the US Department of the Interior Bureau of Reclamation, December 2000.
"CVWD Press Release — Program will Test Methods to Treat Imported Water for Domestic
Use," prepared by the Coachella Valley Water District, October 16, 2007.
"Engineer's Report on Water Supply fegaf ment Assessment Lower Whitewater
River Subbasin Area of Benefit, 2007 - 2008," prepared by the Coachella Valley Water
District, April 2007.
"Petition to List the San Francisco Bay -Delta Population of Longfin Smelt as Endangered under
the Endangered Species Act," prepared by The Bay Institute, Center for Biological Diversity,
and the Natural Resources Defense Council, August 8, 2007.
"Residential End Users of Water, Project #241A," prepared by the American Water Works
Association, Winter 1999/2000.
"Technical Analysis of Regional Water Supply and Demand in the Coachella Valley Water
District," prepared by Terra Nova Planning and Research, March 13, 2008.
"The State Water Project Delivery Reliability Report 2007, "'draft document, prepared by the
California Department of Water Resources, Bay -Delta Office, December 20, 2007.
Stanw
LA QUINTA RESORT REDEVELOPMENT PROJECT
WATER SUPPLY ASSESSMENT
Report Preparers
February 27, 2009
6.0 Report Preparers
Katherine Walters, Project Planner, Stantec Consulting, Inc.
39
J
ljejG
t
Appendix A
Water Demand Dwbons for the La
Quinta Resort Specific -Plan Amendment
t
Stantec
LA QUINTA RESORT REDEVELOPMENT PROJECT
WATER SUPPLY ASSESSMENT
Water Demand Projection Methodology
The following is a description of the methodology utilized in developing the demand projections
for the La Quinta Resort Redevelopment Project (Project) Water Supply Assessment.
EXISTING WATER USE METHODOLOGY
The existing water use was taken from CVWD records for the water meters onsite. Water use
for 2007 and 2008 was available, but the most recent water use for 2008 was used for purposes
of comparison. Based on the development plan and the demolition plan, the water use for
existing uses that will remain as part of the plan. and the water use for those buildings planned
for demolition were delineated and the total water use was calculated. This can be seen in
Table 2 -2 of the Water Supply Assessment.
LANDSCAPE WATER DEMAND METHODOLOGY
The recently enacted CVWD Landscape Ordinance 1302.1 requires that developer/builder-
installed landscape must follow the ordinance and is subject to a maximum water allowance
annually. La Quinta Resort falls within Zone 1 as defined by the CVWD Evapotranspiration map.
This translates into an estimated ann al ba �es of reference evapotranspiration. To
calculate the Maximum Annual Ap ,the following equation from Ordinance
1302.1 was used:
MAAWA = [ET,, x 0.50 x LA x 0.62]/748
MAAWA = Maximum Annual Applied Water Allowance
ET, = Reference Evapotranspiration (inches per year)
0.50 = ET adjustment factor = 0.38 PF / 0.75 IE
(PF = Plant Factor, IE = Irrigation Efficiency)
LA = Landscaped Area
0.62 = Conversion Factor (to gallons per square foot)
748 = Conversion Factor (to hundred cubic feet)
Using this formula, one acre of desert landscaping in Zone 1 that is compliant with the CVWD
Ordinance will have a Maximum Water Allowance (MWA) of. 1029.2 CCF. Using a similar
formula, the water demand from one acre of recreational turf can also be estimated. This was
found to be 1440.1 CCF for Zone 1.
Both of these demand factors were reduced by 7% as a buffer to ensure that the MWA will not
be exceeded. This reduces both demand factors to 957.16 CCF for low -water landscaping and
1339.3 CCF for recreational turf. This area, as accepted by CVWD, uses a 35% return flow
reduction to account for percolation of water through the ground from outdoor water uses.
Stantec
LA QUINTA RESORT REDEVELOPMENT PROJECT
WATER SUPPLY ASSESSMENT R
Water Demand Projection Methodology
February 27, 2009
The Landscape Architect, Forrest K. Haag, evaluated the existing landscaping onsite and the
proposed, ordinance - compliant, landscaping for the portions of new development. Thee
evaluations are attached as exhibits at the back of this appendix. .
The total demand for water due to landscaping on the site (both existing and new /proposed) is
24899 CCF, or 1,945 CCF per year. Since the existing landscaping is not necessarily low -water
landscaping and was. not subject to the CVWD ordinance, the annual applied water use is
actually higher than that allowed by the ordinance. However, in those areas that will be
completely new landscaping, the. annual applied water use is 908.4 CCF, much less than the
Maximum Water Allowance above.
INDOOR WATER DEMAND METHODOLOGY
Indoor water use has been reduced through the mandated low -flush toilets (no greater than 1.6
gallons per flush), low -flow showerheads, aerated faucets, and energy -star appliances. A
dramatic reduction of the indoor water use can be found strictly because the development will
have new construction of residences and commercial properties that will use these water - saving
devices.
Table A -1 shows the land use acreages each t
ypppf land use. The water demand (Table A-
2) was calculated using the updated de an rffltr the Coachella Valley per conversations
with Megan Brown of CVWD.
Table A -1 Land Use Acreages
Planning
Acres
Subarea
Residential
Existing
Commercial
New
Commercial
Existing
Hotel
New
Hotel
Existing
Villas
New
Villas
Subarea A
5.5
0
0
0
0
35.11
0
Subarea B
0
0
5
01
0
0
4.03
Subarea C
.0
3.03
5.97
0
2
0
0
Subarea D
0
0
0
0
0
0.
5.86
TOTAL
5.5
3.03
10.97
0
2
35.11
9.89
Table A -2 Water Demands
Building Type
Acreage
Demand Factor,
acre-ft/ac/ r
Water Demand,
acre-ft/year
New Hotel Rooms
2
3.25
6.5
New Hotel/Ancillary Commercial
5.97
1.49
8.9
New S a Wellness /Commercial
5
3.25
16.3
New Villas
.9.89
2.05
20.3
TOTAL
22.86
51.9
2 .
StadK
LA QUINTA RESORT REDEVELOPMENT PROJECT
WATER SUPPLY ASSESSMENT
Water Demand Projection Methodology
February 27, 2009
TOTAL WATER DEMAND
The total water demands, based on calculated indoor water use and calculated outdoor water
use, along with the existing water demands that will not change is
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7
• 1
Appendix B
Water Resources Litigation and Other
Actions
P
. Y
Terra Nova Planning and Research
March 19, 2.008
For the Panorama Specific Plan
Water Supply Assessment and Verification
APPENDIX .B
Water Resource Litigation and Other Actions
Prepared in Support of the
Panorama Specific Plan
Water Supply Assessment and Verification
Prepared by
Tc rra 'spa ~ra Plawx ng ;dnd RL- search, l ic..
400 S. Farrell Dr., Suite B -205
Palm Springs, CA 92262
March 19, 2008
WATER SUPPLY ASSESSMENT AND WATER SUPPLY VERIFICATION
' PANORAMA SPECIFIC PLAN (3/19/08)
TECHNICAL APPENDIX B
' Water Resource Litigation and Other Actions
' The following is a summary of background information that is to support the Panorama Water Supply
Assessment for the Coachella Valley Water District. This information includes pertinent legal actions
and other actions that may impact the reliability of water resources in Southern California and the
' Coachella Valley.
Protection of the Delta Smelt and the Lonafin Smelt
' The delta smelt is a small fish with a typical adult size of 2 -3 inches that is found only in the
Sacramento -San Joaquin Estuary. The delta smelt was listed as a threatened species by the U.S. Fish and
Wildlife Service and by CDFG 1993. The delta smelt population is affected by the amount of outflow
' from the estuary. Biological studies suggest that the decline of the delta smelt may be the result of
toxics, exotic species and/or freshwater exports out of the delta by the state and federally operated water
projects since 2001.' On August 31, 2007, U.S. District Court Judge Wanger ruled in the case of NRDC
' vs. Kempthorne, that the 2005 delta smelt biological opinion was invalid and that the US Fish and
Wildlife Service shall prepare a new opinion (expected in late 2008).
1
As a result, the judge issued a prohibitory injunction against the US Bureau of Reclamation (USBR) and
DWR to operate the SWP /Central Valley Project in the interim, and any operations must be consistent
with the suite of actions the judge ordered based upon proposals submitted by the parties. Those actions
include enhanced surveys and monitoring, as well as operational constraints from late December 2007
through June 2008. Actual water supply reductions will depend on fish, weather and flow conditions in
the Delta and how reductions are divided between the state and federal projects.
The operational constraints of the judge's decision include a series of restrictions on state and federal
water project operations in the Sacramento San Joaquin Delta selected from remedies submitted by
environmental groups as well as state and federal resource agencies. Based on initial estimates supplied
by the state, the Metropolitan Water District of Southern California and water purveyors supplying
southern California stand to lose as much as 30 percent of their supplies during a normal water year
(with smaller cuts during dry years) from northern California next year and possibly longer, under the
preliminary ruling.2 This ruling will reduce Table A allocations in 2008, and depending on the biological
opinion due in June 2008 water restrictions could continue beyond 2008.
However, the judge reserved to DWR and USBR "the right on reasonable notice to deviate from the
prescriptive remedies, if necessary to protect public health, safety and the human environment." During
the hearing, the judge had indicated that public health, safety and human environment concerns were not
necessarily limited to the maintenance of emergency water supplies for schools, hospitals or fire
departments, but could include, depending upon the circumstances, significant effects related to
agricultural land fallowing and/or subsidence from increased groundwater pumping necessitated by the
absence of project water.
1 "Judge Throws Out Biological Opinion for Delta Smelt," Press Release, Natural Resources Defense Council, May 2007.
: "Metropolitan Water District of Southern California News Release," prepared by the Metropolitan Water District of
Southern California, August 31, 2007.
B -2
WATER SUPPLY ASSESSMENT AND WATER SUPPLY VERIFICATION
PANORAMA SPECIFIC PLAN (3/19/08) '
TECHNICAL APPENDIX B
On October 22, 2007 the opposing parties provided the judge with drafts of the final order, including '
findings of fact and conclusions of law. The judge is currently review these draft documents and is
expected to make a final ruling on the case in early 2008.
As a result of judge's decision SWP deliveries, which have averaged the aforementioned 77.3% per '
year, will be substantially cut for the next year and possibly longer. The percentage of SWP Table A
water allocated to CVWD that may actually be delivered in future years is currently unclear until the '
new OCAP process in completed. As previously noted, this reduction in SWP Table A water is expected
to have a limited direct effect on the Lower Valley Aquifer, although estimated annual subsurface flows
between the Upper and Lower Valley Aquifer will also be affected. I
The longfin smelt is a close relative to the delta smelt that lives in the San Francisco Bay -Delta and is
believed to be impacted by water exports from the San Joaquin River Delta.3 In February 2008, the '
California Fish and Game Commission accepted the long fin smelt as a candidate species for listing
under the California Endangered Species Act (ESA). Under the California ESA, when a species is
accepted as a candidate. species it has the same level of protection as if it was a listed threatened or '
endangered species. Therefore, the Commission adopted regulations meant to protect this species that
may impact the SWP deliveries. Preliminary estimates of the possible impacts of Long Fin Smelt
protection on SWP deliveries are between 0 and 400,000 acre feet per year. ,
The Department of Water Resources has issued a draft 2007 SWP Reliability Report that includes
provisions for water supply reductions as a result of the delta smelt and other environmental issues. This '
is further discussed in Appendix C to this WSA (Technical Appendix C - Coachella Valley Water
District Technical Analysis of Regional Water Supply and Demand, Terra Nova Planning & Research,
March 2008).
In response to the potential impacts to the delta and reductions of water deliveries to southern California,
the Delta Vision Blue Ribbon Task Force was developed by the Governor's office in order to provide a '
sustainable management program for the Sacramento-San Joaquin Bay Delta. The Delta Vision Task
Force is a seven - member independent panel whose recommendations are non - binding but could be used
by the Governor in crafting a new policy for the delta. The Task Force is currently drafting a report due '
out in 2008 that identifies $5.9 billion for a comprehensive water plan, which includes $1 billion for
delta restoration and a new system for diverting water around the San Joaquin delta and considers the
construction of new reservoirs and rock dams to further protect sensitive species as well as provide '
reliable water supplies to southern California.'
Pacific Coast Federation of Fishermen's Association (PCFFA) vs. Gutierrez ,
On October 3, 2007, Judge Wanger reviewed the merits of a companion lawsuit to the NRDC vs.
Kempthorne, in which the Pacific Coast Federation of Fishermen's Association (PCFFA) vs. Gutierrez t
challenged the salmon and steelhead biological opinion issued by the National Marine Fisheries Service
in 2004. The plaintiffs allege similar types of deficiencies with this biological opinion, with an emphasis
"Petition to List the San Francisco Bay-Delta Population of Lonfin Smelt as Endangered Under the Endangered Species A " '
prepared by The Bay Institute, Center for Biological Diversity, and the Natural Resources Defense Council, August 8, 2007.
° "Preliminary Visions Recommendations Report," prepared by the Delta Vision Stakeholder Coordination Group, August '
2007.
B -3 ,
WATER SUPPLY ASSESSMENT AND WATER SUPPLY VERIFICATION
' PANORAMA SPECIFIC PLAN (3/19/08)
TECHNICAL APPENDIX B
' on the potential adverse impacts to species and habitat caused by changes to cold -water temperatures
due to the reduction in water levels in the Sacramento River, and related changes in the methodology of
species management.
The judgment on this case is still pending. However, similar to NRDC vs. Kempthorne, this case also
' contends that reductions of local waters in the San Joaquin River impact endangered species.
Colorado River Interim Guideliness
CVWD receives approximately 40% of their overall water supply from the Colorado River.' Up until the
approval of the Colorado River Interim Guidelines for lower basin shortages for lakes Powell and Mead
in December 2007, the Department of the Interior (DOI) did not have specific set of operational
' guidelines in place to address the operations of these lakes during drought and low water conditions. .
These additional operational guidelines are expected to improve BOR's management of the Colorado
' River by considering trade -offs between the frequency and magnitude of reductions of water deliveries,
and considering the effects on water storage in Lake Powell and Lake Mead, and on water supply, power
production, recreation, and other environmental resources. In addition, these guidelines will provide
users of Colorado River water, particularly those in California, Arizona, and Nevada, a greater degree of
predictability with respect to the amount of annual water deliveries in future years, particularly under
' drought and low reservoir conditions. And finally this will provide additional mechanisms for the
storage and delivery of water supplies in Lake Mead to increase the flexibility of meeting water use
-needs from Lake Mead, particularly under drought and low reservoir conditions. As a result, recipients
'--of Colorado River Water, including CVWD, will receive deliveries with a higher degree of reliability.
I -
"Colorado River Interim Guidelines for Lower Basin Shortages and Coordinated Operations for Lakes Powell and Mead,
Final Environmental Impact Statement," .prepared by the US Department of the Interior, Bureau of Reclamation, November
' 2007, Record of Decision signed December 2007.
e "Coachella Valley Water Management Plan," Section 4, prepared by the Coachella ValleyWater District, September 2002.
B-4
Appendix C
Coachella Valley Water District
Technical Analysis of Regional Water
Supply and Demand
Draft
Prepared by
Terra Nova Planning and Research
March 19, 2008
For the Panorama Specific Plan
Water Supply Assessment and Verification
1 .
APPENDIX C
Coachella Valley Water District
Technical Analysis of Regional Water Supply and Demand
Prepared in Support of the
Panorama Specific Plan
Water Supply Assessment and Verification
Prepared by
Terra. Nova Plarn iug and ke"-arch, Inc..
400 S. Farrell Dr., Suite B -205
Palm Springs, CA 92262
• March 19,. 2008
N
' WATER SUPPLY ASSESSMENT AND WATER SUPPLY VERIFICATION
PANORAMA SPECIFIC PLAN (3/19/08)
TECHNICAL APPENDIX C
Technical Analysis of Regional Water Supply and Demand in the
' Coachella. Valley Water District
IIntroduction
This Appendix has been prepared to present the detailed analysis conducted on regional water supply
' and demand. It describes trends in supply and demand, and elaborates on the various sources of supply
currently available to the Coachella Valley Water District (CVWD). It also provides details on the
normal, single and multi -dry years water supply scenarios that are analyzed in this document. The
' Appendix also provides a summary of findings and conclusions of the analysis. All of the tables
referenced in the text below can be found at the end of this Appendix.
' 1. Demand
The CVWD water demand background and setting for the Panorama Specific Plan Water Supply
' Assessment (WSA) is based on the CVWD Urban Water Management Plan (UW?V1P) prepared for
CVWD in 2005. The demands in the 2005 UWMP are specifically those of CVWD and include the
agricultural and golf course demand supplied by CVWD, in addition to CVWD's domestic water
t demands. The 2005 UWMP demands were based on analysis conducted for CV WD's Draft Program
Environmental Impact Report for Coachella Valley Water Management Plan and State Water Project
Entitlement Transfer, dated June 2002 (2002 Coachella Valley Water Management Plan). The
' demands in the 2002 Coachella Valley Water Management Plan ( CVWMP) are for the entire
Coachella Valley.
The 2002 CVWMP is currently being updated to reflect the changes in land use patterns since 2002
(draft 2008 CVWMP). These changes include additional development in the east or lower valley with
' some agricultural land being converted into residential or commercial development. Table C -1
contains the demands for 2015 and 2035 as cited in the 2002 CVWMP and the draft 2008 CVWMP
and broken out by type of use. The total valley-'wide demand is projected to increase (at the 2015 data
point) by 0.06 percent (433 acre feet per year) in 2015, with increases projected to reach 1.77 percent
(14,587 acre feet per year) in 2035. Agricultural use is now projected to decrease by 32 percent in 2035
and the municipal demand is projected to increase by 31 percent in 2035. Because the total demand did
' not change significantly between the 2002 CVWMP and the draft 2008 CVWMP, the demand data
from the 2005 UWMP is used in this WSA.
' 2. Supply
The following discussion, tables and analysis describe the current and future water supply conditions
' for the Aquifer serving the Coachella Valley and the subject Panorama Specific Plan site. In addition
to addressing groundwater in storage, the supply analysis also describes other sources of supply
available to CVWD and its users. The following represent the major sources -of supply that are
' discussed and how they are used in preparing the WSA.
a. Groundwater: The groundwater supply is discussed in the 2005 UWMP. The supplies contained in
' it were used for the WSA.
b. Groundwater Storage: As sources of supply change are accounted for in the WSA, the amount of
' Groundwater Storage changes to make up the difference between the demand and the supply. In the
1
WATER SUPPLY ASSESSMENT AND WATER SUPPLY VERIFICATION '
PANORAMA SPECIFIC PLAN (3/19/08)
TECHNICAL APPENDIX C '
following tables, a positive number means that water is being pumped from the groundwater basin
and a negative number means that water is being put into storage in the groundwater basin.
c. Coachella Canal Water: The Coachella Canal water supply (Colorado River) is discussed in the '
2005 UWMP. The activities concerning the Colorado River since 2005 and their impacts on
CVWD's supply of Coachella Canal water were reviewed and it was determined that the supply data ,
in the 2005 UWMP were still valid and were used in the WSA.
d. Recvcled_Water: The recycled water supply is discussed in the 2005 UWMP and no changes were '
made to it in the WSA:
e. Desalinated Drain Water: The desalinated drain water supply is discussed in the 2005 UWMP and ,
no changes were made to it in the WSA.
f. SWP Exchange Water: The SWP exchange water supply is discussed in the 2005 UWMP. Several '
changes have occurred since the 2005 UWMP was prepared and they are discussed below.
(1) Additional Table A Amounts: Desert Water Agency (DWA) and CVWD have purchased two '
blocks of additional SWP. water as shown in Table C -2, which has occurred since the 2005 UWMP
was prepared..These purchases result in an increase in the Maximum Table A Amount of the two '
agencies of 23,000 acre feet per year starting in 2010.
(2) DWR SWP Reliability Report: The Department of Water Resources has issued a draft 2007 ,
SWP Reliability Report (2007 Reliability Report) that includes provisions for changes in the
hydrologic cycle due to potential future climate changes and incorporates restrictions on future
deliveries from the SWP and the Federal Central Valley Project resulting from interim operating '
rules from a December 2007 Federal Court order. Table C -3 shows the long -term average delivery
and the dry period deliveries under current conditions as a percent of Maximum Table A Amount.
Table C -4 shows the long -term average delivery and the dry period deliveries under future '
conditions (2027) as a percent of Maximum Table A Amount.
(3) Long Fin Smelt and Other SWP Restrictions: In February 2008, the California Fish and Game ,
Commission accepted the Long Fin Smelt as a candidate species for listing under the state
Endangered Species Act (ESA). Under the California ESA, when a species is accepted as a
candidate species it has the same level of protection as.if it was a listed threatened or endangered '
species. Therefore, the Commission adopted regulations meant to protect this species that may
impact the SWP deliveries. Preliminary estimates of the possible impacts of Long Fin Smelt
protection on SWP deliveries are between 0 and 400,000 acre feet per year. In addition to the Long '
Fin Smelt, there may be other restrictions on deliveries from the SWP. Therefore, in this WSA a
reduction in SWP reliability is being made in the long term average and multi-year dry period. No
reduction is being made in the single dry year as the delivery amount is so low (6% to 7 %) that '
these additional restrictions would not have any impact.
.(4) SWP Reliability for WSA: To compute the reliability percentage in 2007 and 2027, the data '
from Table B -3 and Table B -7 of the 2007 Reliability Report were used. This SWP reliability
projections are the result of computer modeling by DWR to reflect the results of adjusting 82 years
of hydrology to incorporate the results of climate change models. SWP reliability projections also '
take into account the existing physical facilities and the regulatory restrictions, including the recent
Federal court order, which were used to obtain the deliveries for 82 years. These deliveries were
2 '
' WATER SUPPLY ASSESSMENT AND WATER SUPPLY VERIFICATION
PANORAMA SPECIFIC PLAN (3/19/09)
TECHNICAL APPENDIX C
divided b the Table A Amount requests for each year to obtain the reliability percentage for each
Y �1 Y tY P �
' year. These data were then ranked and the long term average demand for 2007 and 2027 was
determined. The percentage values determined using this method results is higher values in 2007
than the values in the 2007 Reliability Report, which divided the projected deliveries by the
Maximum Table A Amount of 4.133 million acre feet. The value for 2027 is close to the 2007
' Reliability Report values as the requested deliveries are nearly the same as the Maximum Table A
Amount. Table C -5 shows the reliability percentages used in the WSA.
(5) MWD Callback: In 1984, MWD, DWA and CVWD entered into an advanced delivery
agreement which allowed MWD to store water from its Colorado River Aqueduct in the Coachella
' Valley. Prior to this agreement, DWA and CVWD were exchanging their annual SWP Table A
Amount with MWD for the same amount of water from MWD's Colorado River Aqueduct. This
was done because the SWP does not extend into the Coachella Valley. This agreement allows
MWD to deliver more water into the Coachella Valley during wet period or period when it has
excess water and to build a credit that it can use to provide the water to exchange for DWA and
CVWD's Table A Amounts during dry periods. This creates a conjunctive use program among the
' three agencies.
In 2003, MWD, DWA and CVWD entered into an exchange agreement where by MWD
transferred title to 100,000 acre feet of its SWP Maximum Table A Amount to DWA and CVWD.
Under the agreement, MWD obtained the right. to callback the SWP water for its use for a
maximum number of times in a given period of years.. The 100,000 acre feet was divided into two
50,000 acre foot blocks. The 100,000 acre feet transfer with MWD provides that after 2015, MWD
can recall the first 50,000 acre feet in 50 percent of the years and the second 50,000 acre feet in 75
percent of the years. Prior to 2016, MWD may recall the water more often. For the Panorama
' = WSA, the 'callback criteria after 2015 were used and it was assumed that MWD would recall the
water to the maximum extent allowed.
The data from Table B -3 and Table B -7 of the 2007 Reliability Report were used to determine the
average water deliveries in the 50 percent driest years and the 75 percent driest years. Linear
proration was used to obtain the yearly values for years 2007 through 2027. These data were used
to obtain the MWD callback water for the first and second 50,000 acre feet, and they were summed
to obtain the total MWD callback for each year. The reliability percentage and the DWA and
CVWD Maximum Table A Amount without the MWD 100,000 acre feet transfer were used to
obtain the amount of SWP water deliveries for DWA and CVWD after the total MWD callback
were deducted. These values were multiplied by the share that CVWD obtained for its use based on
the ratios from the 2005 UWMP. The ratios were linearly prorated to obtain the values for each
' year. Table C -6 •contains the DWA and CVWD Maximum Table A Amount, the reliability
percentage, the supply available to the Coachella Valley as a whole and the supply available to
CVWD for its own use. The methodology used in this WSA is the same as that was used in the
2005 UWMP.
g, Long -Term Average SWP Deliveries: Table C -7 contains the amount of SWP supply that is
' available to CVWD for its own use as the long -term average SWP Supply. The methodology that
was used in the WSA is.the same as that used in the 2005.UWMP.
' h. Single Dry Year SWP Deliveries: The single dry year SWP delivery analysis used the driest year
in the 82 years of data and was calculated in two ways. One method was to use the methodology
used in the 2005 UWMP. Table C -8 contains the supply available to CVWD for its own use from
3
i
WATER SUPPLY ASSESSMENT AND WATER SUPPLY VERIFICATION
'
PANORAMA SPECIFIC PLAN (3/19/08)
TECHNICAL APPENDIX C
the first method. It assumed that no SWP would be delivered during the single dry year. The second
method was based on the MWD- DWA -CVWD advanced delivery agreement and assumed that
deliveries would be made from the advanced delivery account if water was in it, or if not actual
'
water deliveries would be made by MWD. In the second method, .6 percent was the delivery
reliability used for the SWP supply. The delivery reliability factor was not reduced as the delivery
amount is so low (6% to 7 %) that the additional restrictions for the Long Fin Smelt and other
,
potential SWP issues would not have any meaningful impact. These values were multiplied by the
share of SWP deliveries that CVWD obtained for its use based on the ratios from the 2005 UWMP.
The ratios were linearly prorated to obtain the values for each year. The demands in dry years were
'
increased by 4.7 percent, as was done in the 2005 UWMP. Table C -9 contains the SWP supply,
available to CV WD for its own use from the second method.
i. Multiple Dry Years SWP Supply: For the multiple dry year situations, the case of a three -year
drought was used as was done in the 2005 UWMP. The Multiple Dry Years Supply was calculated in
two ways. One method was to use the methodology that was used in the 2005 UWMP. It assumed
'
that no SWP would be delivered during the multiple dry years. The second method was based on the
MWD- DWA -CVWD advance delivery agreements and assumed that deliveries would be made from
the advanced delivery account if water was in it, or if not actual water deliveries would be made by
'
MWD. The supply was calculated assuming that the year before and after the three -year drought were
the long -term .average year. Five five -year periods were calculated between 2007 and 2027. Data
from the 2007 Reliability Report for the 2 -year drought and the 4 -year drought were averaged to
'
obtain the reliability percentages for the 3 -year drought in 2007 and 2027. Linear proration was used
to obtain the yearly values for year 2007 through 2027. The demands in dry years were increased by
4.7 percent as was done in the 2005 UWMP, and dry years that became normal years were decreased
,
by the equivalent amount. Table C -25 is an example of the calculations.
3. Projected Normal Year (Long Term Average) Water Supply and Demand
A new table (Table C -11) was prepared to update the information contained in Table 8 -1 of the
UWMP to reflect the changes resulting from the 2007 Reliability Report using the data described
'
above. It results in the amount of SWP deliveries being reduced and the withdrawal from groundwater
in storage being increased. The demand is the same as that contained in Table 8 -2 of the UWMP and is
not included. Table 8 -3 of the UWMP is unchanged and is also not included.
4. Projected Single Dry Year Water Supply and Demand
'
Two new tables were prepared to update the information contained in Table 8-4 of the UWMP to
reflect the changes resulting from the 2007 Reliability Report using the data described above. The first
table (Table C -12) assumes no SWP deliveries during the single dry year as is done in the UWMP.
'
This does not change the SWP deliveries in the dry year. The second table (Table C -13) is based on
SWP deliveries being made in accordance with the advanced delivery agreement. This results in a
'
small amount of SWP being delivered in the single dry year; in turn, the withdrawal from groundwater
storage is decreased by the same amount. The demand is the same as that contained in Table 8 -5 of the
UWMP and is not included. Table 8 -6 of the UWMP is unchanged and is not included.
'
5. Projected Multiple Dry Year Water Supply and Demand
'
For the multiple dry year scenarios, the case of a three -year drought was used as was done in the 2005
UWMP. The supply was calculated assuming that supply for the years before and after the three -year
'
4
0
1
WATER SUPPLY ASSESSMENT AND WATER SUPPLY VERIFICATION
PANORAMA SPECIFIC PLAN (3/19/08)
TECHNICAL APPENDIX C
drought were the long -term average year. Five five -year periods were calculated for the period between
2007 and 2027. Two new tables were prepared for each. of the supply tables in the 2005 UWMP
(Tables 8 -7, 8 -10, 8 -13 and 8 -16) to update the information to reflect the changes resulting from the
2007 Reliability Report; these tables were prepared using the data described above. The first series of
tables (Tables C -14, C -18, C -20 and C -24) assumes no SWP deliveries during dry years, consistent
with the 2005 LRVW. This does not change the SWP deliveries in the dry years. The second series of
tables (Tables C -15, C -19, C -21, C -23 and C -25) is based on SWP deliveries being made in
accordance with the advanced delivery agreement. New demand tables and new supply and demand
tables were prepared for the period ending in 2011 and 2027 and are contained in Tables C -15, C -16,
C -26 and C -27.
6. Summary
The 2007 Reliability Report includes the changes in the hydrologic cycle due to potential future
climate changes and restrictions on the SWP, as well as the Federal Central Valley Project, resulting
from interim operating rules from a December 2007 Federal Court order on the Delta Smelt and its
protection. The data from the 2005 UWNT was updated to reflect the impact of the 2007 Reliability
Report on CVWD's water supply, and an additional reduction to allow for possible impacts to
deliveries due to restrictions associated with protection of the Long Fin Smelt and any other
restrictions on'the SWP.
Figure Al shows the amount of water withdrawn from or added to groundwater storage on the long-
term average (normal year), as determined for this WSA and from the 2005 UWMP. The additional
water withdrawn from groundwater storage in the period from 2010 to 2030 is 7,000 acre feet per year
on the long -term average. Figure A2 shows the change in groundwater storage as a percentage of
CVWD's total supply as determined for this WSA and from the 2005 UWMP for the long -term
average. The water withdrawn from groundwater storage, as determined in this WSA as a percentage
of CVWD's total supply, is 2.6 percent in 2010 and 0.5 percent in 2030 for the long -term average. The
additional water withdrawn from groundwater storage as a percentage of CVWD's total supply, as
compared to the 2005 UWMP, is 1.7 percent in 2010 and 2.7 percent in 2030 for the long -term average
as shown in Figure A3.
Figure A4 shows the amount of water withdrawn from groundwater storage on the single dry year (one
year in 82 years or 1.2 percent) with no SWP deliveries as determined for this WSA and from the 2005
UWMP. Groundwater withdrawal is the same as the 2007 UWMP in that both assume no SWP
deliveries in the single dry year.
' . Figure A5 shows the amount of water withdrawn from groundwater storage on the single dry year with
SWP deliveries assumed to be in accordance with the advanced delivery agreement as determined for
this WSA and from the 2005 UWMP. In this case the amount of water withdrawn from groundwater
' storage, as determined by the WSA, is slightly less (0.5 to 0.6 percent) than from the 2005 UWMP.
Figure A6 shows the amount of water withdrawn from groundwater storage on the three -year drought
' assuming no SWP deliveries as determined for this WSA for five year periods ending in 2011, 2015,
2020, 2025 and 2027. The first and last years of each period are assumed as normal SWP delivery
years. The middle three years are assumed to have no SWP water delivered. The maximum amount of
' water withdrawn from groundwater storage is 17.2 percent, as determined in this WSA as a percentage
of CVWD's total supply in the three year drought.
WATER SUPPLY ASSESSMENT AND WATER SUPPLY VERIFICATION '
PANORAMA SPECIFIC PLAN (3/19/09)
TECHNICAL APPENDIX C
Figure A7 shows the amount of water withdrawn from groundwater storage as a percentage of ,
CVWD's total supply for the three -year drought with SWP deliveries in accordance with the advanced '
delivery agreement as determined for this WSA for five year periods ending in 2011, 2015, 2020, 2025
and 2027. The first and last years of each period are assumed as normal SWP delivery years. The
middle three years are assumed to have SWP deliveries in accordance with the advanced delivery
agreement. The maximum amount of water withdrawn from groundwater storage is 12.4 percent as '
determined in this WSA as a percentage of CVWD's total supply in the three -year drought.
Figure A8 shows the amount of water withdrawn from groundwater storage . as a percentage of '
CVWD's total supply for the three -year drought and with SWP deliveries in accordance with the.
advanced delivery agreement as determined for this WSA and from the 2005 UWMP for five year
period ending in 2025. The 2005 UWMP assumes that no SWP deliveries are made during the three- '
year drought. The amount of water withdrawn from groundwater storage, as a percentage of CVWD's
total supply for the three- year drought with SWP deliveries in accordance with the advanced delivery ,
agreement, is 5.2 percent to 5.7 percent less than for the same period from the 2005 UW T.
7. Conclusions
■
The 2005 UWMP indicated an average of 7,000 af/y of aquifer replenishment for the period 2010
through 2030. This compares to a 7,000 af/y reduction of aquifer storage under. the . revised supply
projections adjusted for SWP reliability reductions. This results in a very modest reduction in aquifer ,.
storage that will be further addressed through additional water supply purchases, water conservation,
and source substitution. '
Appendix C (March 19, 2008)
Tables for Appendix C to the Panorama Water Supply Assessment
Table C -1
' Water Demand in the Coachella Valley (2015 - 2035)
Notes:
(1) From Dave Ringel, MWH, personal communication, March 2008
1
From Table 3.9 of
2002 CVWMP
From Draft 2008
Revision of CVWMP
1
Change In CVWMP 2002 Report to
2008 Draft Report
Component
2015. 1
2035
2015
2035
2015
2035
2016 1
2035
A icultural
(ac r
ac- r
as r
(ac- r
ac- r
ac- r
%
%
Crop Irrigation including
Greenhouses
315 700
322,700
303,876
217,1201
-11&L4
-105,580
-3.7%
-32.7%
Total Agricultural Demand
315 700
322,700
303,876
217120
-11.824
-105.680
-3.7%
-32.7%
Urban
Municipal
243.900,
337,200
268 734
441,824
24,834
104,624
10.2%
31.0%
Industrial
2.3001
2.300
2.250
2,250
-50
-50
-2.2%
-2.2%
Total Urban Demand
246,200
'339,500
270 984
444,074
24784,
104,574
10.1%
30.8%
Golf Course Demand
131,500
131,500
118,969
147,089
-12,531,
15,589
-9.5%
11.9%
Fish Farms and Duck Clubs
Fish Farms
25 800
25,800
25 819
25,819
19
19
0.07%1
0.07%
Duck Clubs
4 600
4,600
4,586
4,586
-14
-14
-0.31 %
-0.31%
Total Fish Farms and Duck
Clubs
30,4001
._ 30 400
30A05
30,4051
5
5
0.01%
0.01%
Total Demand
723 800
824100
724 233
838 687
433
14 587
0.06%
1.77%
Notes:
(1) From Dave Ringel, MWH, personal communication, March 2008
1
Table C -2
DWA and CVWD SWP Supply
Appendix C (March 19, 2008)
Maximum Table A Amount
acre feet/ ear
Maximum Table A Amount '
acre fee ear
Benenda Mesa Transfer (Starting in 2010
CVWD
DWA
Total
Original Contracts
. 23 100
38 100
61,200
Tulare Lake First Transfer
9,900
-
9,900
MWD transfer
88,100
11 900
100,000
Total 2007
121,100
50,000
171,100
Maximum Table A Amount '
acre fee ear
Benenda Mesa Transfer (Starting in 2010
12,000
1 4,000
16,000
Tulare Lake Second Transfer (Starting in 2010
5,2501
1,750
1 7,000
Future Total 2010
138,3501
56,750
194,100
'
1
1
1
1
1
1
i
Appendix C (March 19, 2008)
' Table C -3
Average and Dry Period SWP Table A Deliveries from the Delta Under Current Conditions
Source: Table 6-5 of the Draft State Water Project Reliability Report 2007
1) 4,113TAF/Year
' 2) 1922 -1994 for 2005 SWP Delivery Reliability Report; 1922 -2003 for Update with 2007 Studies.
3) Values reflect averaging annual deliveries from the two scenarios of Old and Middle River flow
Table C-4
Average and Dry Period SWP Table A Deliveries from the Delta Under Future Conditions
SWP Table A Delivery from the Delta (in percent of maximum Table A')
Single
2 -Year
4 -Year
6 -Year
6 -Year
Long -term
Dry Year
Drought
Drought
Drought
Drought
Studi of Current Conditions
Avera e2
1977
1976 -1977
1931 -1934
1987 -1992
1929 -1934
2005 SWP Reliability Report,
68°%
4°%
41%
32%
42%
37%
Study 2005
[Update with 2007 Studies'
63%
6°%
34°%
1 35%
1 35%
34%
Source: Table 6-5 of the Draft State Water Project Reliability Report 2007
1) 4,113TAF/Year
' 2) 1922 -1994 for 2005 SWP Delivery Reliability Report; 1922 -2003 for Update with 2007 Studies.
3) Values reflect averaging annual deliveries from the two scenarios of Old and Middle River flow
Table C-4
Average and Dry Period SWP Table A Deliveries from the Delta Under Future Conditions
' Source: Table 6-14 of the Draft State Water Project Reliability Report 2007
1) 4,113TAF/Year
2) 1922 -1994 for 2005 SWP Delivery Reliability Report; 1922 -2003 for Update with 2007 Studies.
3) Values reflect averaging annual deliveries from the two scenarios of Old and Middle River flow
1
t "
' 3 of 34 .
able A Delivery from the Delta On percent of maximum Table A')
Single
2 -Year
4-Year
6jYear
6 -Year
term
Dry Year
Drought
Drought
Drought
Drought
Stud of Current Conditions
EAvera=2
1977
1976 -1977
1931 -1934
1987 -1992
1929 -1934
2005 SWP Reliability Report,
%
5°%
40°%
33°%
42%
38°%
Stud 2005
U date With 2007 Studies'
69 °%
1 7 °%
26 °% - 27 °%
32% - 37%
33 °% - 35 °%
33% - 36%
' Source: Table 6-14 of the Draft State Water Project Reliability Report 2007
1) 4,113TAF/Year
2) 1922 -1994 for 2005 SWP Delivery Reliability Report; 1922 -2003 for Update with 2007 Studies.
3) Values reflect averaging annual deliveries from the two scenarios of Old and Middle River flow
1
t "
' 3 of 34 .
I
■
■
Table C-6
' CVWD' Share of SWP Water
Table A Amount
■
Appendix C (March 19, 2008)
Year
Table A
w/o MWD
of
MWD
Transfer
of '
SWP Avg
Reliability
%
Total Supply
of
CVWD Share
of SWP Water
of
2007
71,100
100,000
69.0%
82,112
41,523
2008
71,100
100,000
68.2%
81,203
42 615
2009
71,100
100.000
67.5%
80.295
43,672
•2010
94.100.
100,000
66.7%
94,734
53,335
2011
94,100
100 000
66.0%
93652,
54,393
2012
94,100
100 000
65.2%
92!571
55,413
2013
94,100
100,000
64.5%
91,489
56,394
2014
94,100
100.000
63.7%
90.408
57.336
2015
94,100
100,000
63.0%
89,326
58,240
2016
94,100.
100.00
62.2%
86,244
57,659
2017
94,100
100,000
61.5%
87,163
57,074
2018
94,100
100,000
80.7%
86.081
56,486
2019
94,100
100,05-0
59.9%
84.999
55,896
2020
94,100
100,000
59.2%
83,918
1 55,302
2021
94.100
100.00
58.4%
82.836
F 54,473
2022
94,100
100,000
57.7%
81.7
53.647
2023
94,100
100 000
56.9%
80,673
52,825
2024
94,100
100,000
56.2%
79,591
52,005
2025
94,100
100,000
55.40%
78 510
51,188
20261
94,1001
100.000
54.7%
77 428
50 235
2027
94,100,
100,0001
53.9%
76!346
49'.289
5 of 34
. 1
Appendix C (March 19, 2008)
Table C -7
Summary of CVWD Future SWP Supplies '
Normal Year Average long term supply
Year
SWP Max Table A
Amount (4)
ac -ft r
Average
Reliability (1, 5)
Average
Yield
ac -ft r
MWD
Callback (2)
(acft r
Average
Supply (4)
ac-ft r
CVWD Average'
Supply (3)
ac-ft / r
2010
194,100
66.73%
129,617
-34.783,
94,734
53,335
2015
. 194 100
62.96%
122,201
-32.8
89 326
56,240
20240ul
194,100
59.19%
114,885
-30,967
83,918
65,302
20251
194,1001
55.42%1
107,5691
-29,0591
78,6101
51,188
20271
194,1001
53.91%1
104,6431
-28,2961
76.3471
49,289
■
1 Average SWP reliability based on requested deliveries from DWR, Draft State Water Project Delivery Reliability Report 2007..
2 Metropolitan callback amount is based on Metropolitan calling back the transferred 50,000 acre -ft of Table A water in the 50%
'
driest years and the second 50,000 acre-feet in the 75% driest years. From 2005 UWMP
3 CVWD average SWP supply is the proportionate share of the average SWP supply to the Coachella Valley based on the
percent of groundwater produced for domestic supply by CVWD in the Whitewater and Mission Creek subbasins. The remaining
'
water would offset pumping by pumpers in the CVWD and DWA service areas.
4. Total DWA and CVWD
5. Values from 2007 DWR Draft SWP Reliability Report reduced by 10% to account
for Long Fin Smelt and other potential reductions.
'
1
Appendix C (March 19, 2008)
1
Table C -8
1 Summary of CVWD Future SWP Supplies
Single Dry Year
Assumes no SWP deliveries in Single Dry Year
Year
Average
Yield (2)
ao-ft / r
CVWD Average
Supply (1)
ac-ft r
2010
0
0
2015
0
0
20201
0
0
20251
0
0
20271
0
0
20301
0
0
1 1. CVWU average SWP supply is the proportionate share of the average SWP supply to the
Coachella Valley based on the percent of groundwater produced for domestic supply by
1 CVWD In the Whitawater and Mission Crook subbasins. The remaining water would offset
pumping by pumpers in the CVWD and DWA service areas.
2. Total DWA and CVWD
.1
i
1
1
i
7 of 34
Appendix C (March 19, 2008)
Table C -9
Summary of CVWD Future SWP Supplies
Single Dry Year
Assumes SWP deliveries during Single Dry Year per Advanced Delivery Agreements
Year
SWP Max Table A
Amount (4)
ac-ft r
MWD
Callback (2)
ac -ft r
Net SWP
Account (4).
ao-ft r
Average
Reliability (1,5)
Average
Yield (4)
ac -ft r
CVWD Average
Supply (3)
(ac-ft / r
2010
194,100
-100,000
94,100
6.00%
6,646
3,179
2015
194,100
__-100,000
94,100
6.00%
5,646
3,681
2020
194,100
-100,000
94.100
6.00°x6
5,646
3,721
2025
194,100
-100,000
94,100
6.00%
5.646
3,681
2027
194,100
-100,000
94,100
6.00°x6
5 646
3 645
2030
194100
-100,000
94,100
6.00%
5,646
3,591
1 Average SWP reliability based on requested deliveries from DWR, Draft State Water Project Delivery Reliability Report 2007.
2 Metropolitan callback amount is based on Metropolitan calling back the transferred 50,000 acre -ft of Table A water in the 50%
driest years and the second 50,000 acre-feet in the 75% driest years. From 2005 UWMP
3 CVWD average SWP supply is the proportionate share of the average SWP supply to the Coachella Valley based on the percent
of groundwater produced for domestic supply by CVWD in the Whitawater and Mission Creek subbasins. The remaining water
would offset pumping by pumpers in the CVWD and DWA service areas. '
4. Total DWA and CVWD
5. Values from 2007 DWR Draft SWP Reliability Report reduced by 0% to account for Long Fin Smeit and other potential
i
Table C -10
CVWD Share of SWP Water During Multiple Year Drought
' Assumes SWP deliveries during Single Dry Year per Advanced Delivery Agreements
Year
Table A
w/o MWD
of
SWP Avg
Reliability
%
SWP Avg
Reliability
of
NWD share
of SWP
of
2007
71,100
69%
49,051
24,804
2008
71. 100
68%
48,515
25,460
20091
71, 001
67%
47,979
26,095
2010
94,1001
67%
62,790
35 351
2011
94, 100
66%
62,081
36,056
2012
94,100
65%
61,371
38,737
2013
94,100
64%
60.662
37,392
2014
94,100
64%
59,953
38,022
2015
94,100
63%
59,243
38 627
2016
94,100
62%
58,634
38,246
2017
94,100
61%
57,825
37,863
2018
94,100
61%
57,115
37,479
2019
94,100
60%
56,406
37,092
2020
94,100
59%
55,696
36,704
2021
94, 100
58%
54,987
36,160
2022
94 100
58°x6
54,278
35,617
2023
94,100
57%
53.568
35,077
2024
94 100
56%
52,859
34,538
2025
94,100
55%
52,150
34,002
2026
94,100
55%
51,440
33,374
2027
94,1001
54%
50,731
32,752
Appendix C (March 19, 2008)
Appendix C (March 19, 2008)
Table C -11
Modified to reflect 2007 Reliability Report SWP
Based on Table 8-1 UWMP
Projected Normal (Long Term Average) Water Year Supply
Supply Sources
2010
acre- r
2015
acre- r
2020
acre -ft/ r
2025
acre- r
2030
(acre-ft/yo
Groundwater
106,700
123100
123,700
124,200
123,200
Groundwater Storage 1
13,246
14 065
-3,774
7,578
3,499
Coachella Canal Water
318,000
342 000
379,000
404,000
429,000
SWP Exchange Water 2 3
53,335
58,240
1 55,302
51.188
49,289
Recycled Water
23,100
25.100
26,500
27,600
28,300
Desalinated Drain Water
4,000
8 000
8,000
11 000
11,000
Total Supply
518,381
570,505
588,728
625,566
644,288
GW Storage/Total Supply
2.6%
2.5%
-0.6%
1.2%
0.5%
1. Groundwater storage is the difference between demands and supplies. A positive number indicates
groundwater pumped from storage, a negative number indicates water to storage.
2. Includes second Tulare Lake Water Storage District transfer of acre feet of Table AAmount.
3. Values from 2007 SWP Reliability Report reduced by 10% to account
for Long Fin Smelt and other potential reductions.
10 of 34
Appendix C (March 19, 2008)
Table C -12
' Projected Single Dry Year Supply
Update of Table 8-4 UWMP
Assumes no SWP deliveries in Single Dry Year
1
Supply Sources
2010
acre -tU r
2015
acre -ftl r
2020
-ffr
2025
acer
2030
-fV r
Groundwater
106 700
123 100
123 700
124,200
123 200
Groundwater Storage 1
90,945
99,119
79,199
88,168
83,069
Coachella Canal Water
318,000
342,000
379,000
404,000
429,000
SWP Exchancie Water
-
Recycled Water
23,100
25,100
26,500
27,600
28,300
Desalinated Drain Water
4,000
8,000
8 000
11,000
11,000
Total Supply
542,745
597 319
616 399
654 968
674 569
GW Story elTotal Supply
16.8%
16.6%
12.8%
13.5%
12.3%
1. Groundwater storage is the difference between demands and supplies. A positive number Indicates groundwater
pumped from storage; a negative number indicates water to storage.
1
1
1 ,
' 11 of 34
Appendix C (March 19, 2008)
Table C -13
Projected Single Dry Year Supply
Based on Table 8-4 UWMP
Assumes SWP deliveries during Single Dry Year per Advanced Delivery Agreements
Supply Sources
2010
acre -ft/ r
2015
acre- r
2020
acre -ft/ r
2025
(acre-ft/ r
2030
acre- r
Groundwater
106,700
123 100
123 700
124 200
123,20D
Groundwater Storage 1
87,766
95 438
75 478
84,487
79,478
Coachella Canal Water
318,000
342.000
379 000
404 000
429 000
SWP Exchange Water 2 3
3 179
3.681
3.721
3,681
3,591
Re cled Water
23,100
25 100
26 500
27,600
28,300
Desalinated Drain Water
4,000
8,000
8,000
11,000
11,000
Total Supply
542 745
597 319
616 399
654,968
674,569
GW Stora efTotal Supply
16.2%
16.0%
12.2%
12.9%
11.8%
1. Groundwater storage is the difference between demands and supplies. A positive number indicates groundwater
pumped from storage; a negative number indicates water to storage.
2. Includes second Tulare Lake Water Storage District transfer of acre feet of Table A Amount
3. Values from 2007 DWR Draft SWP Reliability Report reduced by 0% to account
for Long Fn Smelt and other potential reductions.
4. Modified to reflect 2007 Reliability Report SWP = 6% for current year
0
r
12 of 34
r
Appendix C (March 19,2008)
Table C -14
Projected Multiple Dry Year Supply Ending 2011
Update and based on Tables 8 -7and 8 -10 from 2005 UWMP
Assumes no SWP deliveries In Multiple Dry Year
' SWP Exchange Water based on draft 2007 Reliability Report
Supply Sources
2007
acre- r
2008
acre- r
2009
acre- r
2010
acre- r
2011
acre -ft/ r
Groundwater
91 800
99 400
102 700
106 700
112 900
Groundwater Storage 1
21 549
86.498
91,721
90,945
11,213
Coachella Canal Water
306,000
310,000
314 000
318 000
322 000
SWP Exchange Water .
41,523
-
54,393
[Re-cycled Water
17,900,
19,200
20,500
23,100
23,500
Desalinated Drain Water
-
-
4,000
4,800
Total Supply
478.772
515,098
528,921
542,745
528,806
GW Storage/Total Supply
4.5%
16.8%
17.3%
16.8%
2.1%
1. Groundwater storage is the difference between demands and supplies. A positive number indicates groundwater r
pumped from storage; a negative number indicates water to storage.
' 2. Time Period changed from 2006.2010 to 2007 -2011
3. Dry year demand increased by 4.7%
Appendix C (March 19, 2008)
Table C -15
Projected Multiple Dry Year Supply Ending 2011
Assumes SWP deliveries during Multiple Dry Year per Advanced Delivery Agreements
Updated and based on Tables 8 -7and 8 -10 from 2005 UWMP
SWP Exchange Water based on draft 2007 Reliability Report
Supply Sources
2007
(acre- r
2008
acre- r
2009
acre- r
2010
acre -ft/ r
2011
acre- r
Groundwater
91 800
99 400
102,700
106,700
112,900
Groundwater Story e 1
21 549
61 038
65 626
55 594
11 213
Coachella Canal Water
306,000
310,000
314,000
318,000
322,000
SWP Exchan a Water 2 3
41.523
25.460
26,095
35,351
54,393
Recycled Water
17,900
19,200
20,500
23,100
23,500
Desalinated Drain Water
-
-
4 000
4 800
Total Supply
478,772!
515 098
528 921
542,745
528,806
GW Storage/Total Supply
4:5%
11.8%
12.4%
10.2%
2.1%
1. Groundwater storage is the difference between demands and supplies. A positive number Indicates groundwater
pumped from storage; a negative number indicates water to storage.
2. Includes second Tulare Lake Water Storage District transfer of acre feet of Table AAmount.
3. Values from 2007 DWR Draft SWP Reliability Report reduced by 3% to account
for Long Fn Smelt and other potential reductions.
4. Time Period changed from 2006 -2010 to 2007 -2011
5. Modified to reflect 2007 Reliability Report SWP
6. -Dry year demand increased by 4.7%
0
14 of 34
Appendix C (March 19, 2008)
Table C -16
Projects Demand During Multiple Dry Year Period Ending 2011
Updated and based on Table 8 -8 and Table 8 -11 UWMP
1
Demand
2007
acre- r
2008
acre- r
2009
(acre-ft/ r
2010
acre- r
2011
(acre-ft/ r)
Domestic Water including Conservation
152,492
164 960
170,261
175 562
172,026
Golf Course and Municipal Non-portable
48,360
57,208
63,783
70,358
71,780
A dculture
277,920
292 930
294 877
296,826
285.000
Total Demand
1 478,772
515 098
528,92 1
542,745
528 806
% of Pro ected Normal Demand
.100%
104.70%
104.70%
104.70%
10 0%
Table C -17
Projected Multiple Dry Year Supply and Demand Ending 2011
Based on Table 8 -9 and 8 -12 UWMP
Projected Multiple Dry Year Supply and Demand
Appendix C (March 19,2008)
1
i. swr txcnange water oases on Gran zuui Kenaowry Kepon
16 of 34
2007
ac-ft r
2008
ac-ft / r
2009
ac -ft r
2010
ac-ft r
2011
ac -ft / r
supply totals
478,772
515.098
528 921
542 745
528,806
Demand totals
478,772,
515,098
528,921
542,745
528,806
Difference Difference as % of Supply
-
Difference as a % of Demand
-
i. swr txcnange water oases on Gran zuui Kenaowry Kepon
16 of 34
Appendix C (March 19, 2008)
Table C -18
Projected Multiple Dry Year Supply Ending 2015
Assumes no SWP deliveries in Multiple Dry Year
Updated and based on Table 8 -10 UWMP
Supply Sources
2011
(acre-ft/ r
2012
0&6- r) (
2013
(acre-ft/ r
2014
acre- r
2015
acre- r
Groundwater
112,900
114,500
115,600
121,100
123,100
Groundwater Stora e 1
11,213
93,574
97,189
96,404
14,065
Coachella Canal Water
322.000
327,000
332.000
337.000
342,000
SWP Exchange Water
54,393
-
58,240
Recycled Water
23 500
23,900
24,300
24,700
25 100
Desalinated Drain Water
4 800
5 600
6 400
7200
8 000
Total Supply
.628806
564,574
575,489
586,404
505
GW Storage/Total Supply
2.1%
16.6%
16.9%
16.4%
2.50/a
' . 1. Groundwater storage is the difference between demands and supplies. A positive number indicates groundwater
pumped from storage; a negative number Indicates water to storage.
2. SWP Exchange Water based on draft 2007 Reliability Report
1 �
1
' 17 of 34
0
Appendix C (March 19, 2008)
Table C -19
Projected Multiple Dry Year Supply Ending 2015
Assumes SWP deliveries during Multiple Dry Year per Advanced Delivery Agreements
Update and based on Table 8 -10 UWMP
Supply Sources
2011
acre -ft! r
2012
acre- r
2013
acre- r
2014
acre- r
2015
acre- r
Groundwater
112 900
114 500
115 600
121 100
123,100
Groundwater Storage 1
11,213
56,837
59 797
58,382
14,065
Coachella Canal Water
322,000
327 000
332 000
337,000
342,000
SWP Exchange Water 2 3
54.393
36.737
37,392,
38.022
58,240
Recycled Water -
23,500
23 900
24 300
24,700
25 100
Desalinated Drain Water
4,800
5 600
6,4001
7,200
8,000
Total Supply
528,806
564 574
575,4891
586,404
670.505
GW Stora e/Total Supply
2.1%
10.1%
10.4%
1. Groundwater storage is the difference between demands and supplies_ . A positive number indicates groundwater
pumped from storage; a negative number indicates water to storage.
2. Includes second Tulare Lake Water Storage District transfer of acre feet of Table AAmount
.3. Values from 2007 DWR Draft SWP Reliability Report reduced by 3% to account
for Long Fin Smelt and other potenital reductions.
4. Modified to reflect 2007 Reliability Report SWP
5. SWP Exchange Water based on draft 2007 Reliability Report
r
r
a
r
Appendix C (March 19,-2008)
1
Table C -20
Projected Multiple Dry Year Supply Ending 2020
' Assumes no SWP deliveries in Multiple Dry Year
Based on Table 8 -13 UWMP
Supply Sources
2016
acre -fU r
2017
(acre-ft/ r
2018
acre -ft/ r
_2019
acre -ft/ r
2020
(acre- r
Groundwater
123,300
123 300
123 400
123 600
123,700
Groundwater Storage 1
12,811
96 991
82 427
80 763
(3,774)
Coachella Canal Water
347,000
351,000
369 000
374 000
379,000
SWP Exchange Water 2 3
57.659
-
-
-
55,302
Recycled Water
25 380
25,660
25 940
26 220
26.500
Desalinated Drain Water
8,000
8,000
8,000
8 000
8,000
Total Supply
574 150
604,951
608 767
612 583
588,728
GW Stora efrotal Supply
2.2%
16.0°x6
13.5%
13.2%
-0.6%
' 1. Groundwater storage is the difference between demands and supplies. A positive number indicates groundwater
pumped from storage; a negative number indicates water to storage.
2. Includes second Tulare Lake Water Storage District transfer of acre feet of Table AAmount.
' 3. Values from 2007 DWR Draft SWP Reliability Report reduced by 3% to account
for Long Fin Smelt and other potenital reductions.
4. Modified to reflect 2007 Reliability Report SWP
5. SWP Exchange Water based on draft 2007 Reliability Report
1 _
1
' 19 of 34
/ e
Table C -21
Projected Multiple Dry Year Supply Ending 2020
Assumes SWP deliveries during Multiple Dry Year per Advanced Delivery Agreements
Based on Table 8 -13 UWMP and updated
1
Appendix C (March 19, 2008)
. 1
1
Supply Sources
2016
acre- r
2017
acre- r
2018
acre -ft! r
2019
(acre-ft/ r
2020
acre- r
Groundwater
123 300
123 300
12-3-14-0-0-
123,600
123,700
Groundwater Storage 1
1 T, 811
59,128
44,948
43,671
(3,774)
Coachella Canal Water.
347,000
351,000
369,000
374,000
379,000
SWP Exchan a Water 2 3
57,659
37,863
37,479
37,092
55,302
Recycled Water
25.380
25,660
25 940
26,220
26,500
Desalinated Drain Water
8,000
8,000,
8,000
8,000
8,000
Total Supply
574 150
604 951
608,767
612,583
588,728
GW Storage/Total Supply
. 2.2%
9.8%
7.4%
7.1%
-0.6%
1. Groundwater storage is the difference between demands and supplies. A positive number indicates groundwater
,
pumped from storage; a negative number indicates water to storage.
2. Includes second Tulare Lake Water Storage District transfer of acre feet of Table AAmount
3. Values from 2007 DWR Draft SWP Reliability Report reduced by 3% to account
for Long Fin Smelt and other potential reductions.
1
4. Modified to reflect 2007 Reliability Report SWP
5. SWP Exchange Water based on draft 2007 Reliability Report
1
J
1
.
1
20 of 34
1
Appendix C (March 19, 2008)
Table C -22
Projected Multiple Dry Year Supply Ending 2025
Based on Table 8 -16 UWMP
Assumes no SWP deliveries in Multiple Dry Year
Supply Sources
2021
acre -ftf r
2022
(acre-ft/ r
2023
(acne-ft/ r
2024
(acre-ft/ r
2025
(acre-ft/ r)
Groundwater
123,200
123,200
124,
124,200
124,200
Groundwater Storage 1
-897
83,486
84 380
86,274
- 7 578
Coachella Canal Water
384,000
389,000.
394,000
399,000
SWP Exchange Water
54.473
0
0
Of
_404,000,
51,1881
Recycled Water
26,720
26,940
27,160
27.380
27,600
Desalinated Drain Water
8,600
9,200
9,800
10,400
11 000
Total Supply
596 096
631 826
639 540
647,264
625 566
GW Storage/Total Supply
-0.2%
13.2%
13.2%
13.3%
12%
' 1..Groundwater storage is the difference between demands and supplies. A positive number Indicates
groundwater pumped from storage; a negative number indicates water to storage.
2. SWP Exchange Water based on draft 2007 Reliability Report
I
Table C -23
Projected Multiple Dry Year Supply Ending 2025
Based on Table 8 -16 UWMP and updated
Assumes SWP deliveries during Multiple Dry Year per Advanced Delivery Agreements
Appendix C (March 19, 2008)
i
Supply Sources
2021
acre- r
2022
(acre-ft/ r
2023
acre -ftl r
2024
acre -fl r
2025
acre- r
Groundwater
123-3-0-0
123,30D
123,400
123 600
123,700
Groundwater Storage 1
-997
47 769
50103
52 336
8,078
Coachella Canal Water
384,000
389,000
394,000
399.000
404;000
SWP Exchan a Water 2 3
54,473
35,617.
35,077
34.538
51,188
Recycled Water
26,720
26,940
27,160
27 380
' 27,600
Desalinated Drain Water
8,600
9200
9,800
1Q 400
11,000
Total Supply
696,096,
631,826
639,540
647,254
625,566
GW Storage/Total Supply
-0.2%
7.6%
7.8%
8.1%
1:3%
1. Groundwater storage is the difference between demands and supplies. A positive number indicates
groundwater pumped from storage; a negative number indicates water to storage.
2. Includes second Tulare Lake Water Storage District transfer of acre feet of Table AAmount.
3. Values from 2007 DWR Draft SWP Reliability Report reduced by 3% to account
for Long Fin Smelt and other potenital reductions.
4. Modified to reflect 2007 Reliability Report SWP
5. SWP Exchange Water based on draft 2007 Reliability Report
22 of 34
Appendix C (March 19, 2008)
1 '
Table C -24
Projected Multiple Dry Year Supply Ending 2027
' Based on Tables 8 -16 and 8 -19 UWMP
Assumes no SWP deliveries in Multiple Dry Year
Supply Sources
2023
acre- r
2024
acre- r
2025
acre -fU r
2026
acre- r
2027
acre- r
Groundwater
124 200
124 200
124 200
123 700
123 200
Groundwater Storage 1
2,846
86 274
88 168
87 449
7 685
Coachella Canal Water
394,000
399.000
404.000
409.000
414 000
SWP Exchange Water
52,825
-
-
-
49,289
Recycled Water
27,160
27,380
27,800
27,740
27,880
Desalinated Drain Water
9,800
10,400
11,000
11,000
11,000
Total Supply
610 831
647 254
654.968
658 889
633 054
GW Storage/Total Supply
014,
.13.3%1
13.5%
13.3%
1.2%
t1. Groundwater storage is the difference between demands and supplies. A positive number Indicates groundwater
pumped from storage; a negative number Indicates water to storage.
2. SWP Exchange Water based on draft 2007 Reliability Report
3. Dry Year Demand increased by 4.7%
1
' 23 of 34
I
Appendix C (March 19, 2008)
Table C -25
Projected Multiple Dry Year Supply Ending 2027
Assumes SWP deliveries during Multiple Dry Year perAdvanced Delivery Agreements
Based on Tables 8 -16 and 8 -19 UWMP
Supply Sources
2023
acre -tV r
2024
(acre- r
2025
(acre-ft/ r
2026
(acre-ft/ r
2027
(acre-ft/ r)
Groundwater
124,200
124 200
124 200
123 700
123 200
Groundwater Storage 1
3,746
51 557
_ 53,891
53 011
718
Coachella Canal Water
394,000
399,000
404,000
409,000
414,000
SWP Exchan a Water 2 3
52.825
35.617
35.077
34,538
49.289
Recycled Water
27,160
27,380
27,600
27 740
27,880
Desalinated Drain Water
9,800
10,400
11,000
11,000
11,000
Total Supply
610,831
647,254
654,968
658,889
633,054
GW Stora elrotal Supply
0.6%
8.0%
8.2%
8.0%
1.1%
1. Groundwater storage is the difference between demands and supplies. A positive number indicates groundwater
pumped from storage; a negative number indicates water to storage.
2. Includes second Tulare Lake Water Storage District transfer of acre feet of Table AAmount.
3. Values from 2007 DWR Draft SWP Reliability Report reduced by 3% to account
for Long Fin Smelt and other potential reductions.
4.' SWP Exchange Water based on draft 2007 Reliability Report
5. Modified to reflect 2007 Reliability Report SWP
6. Dry year demand Increase by 4.7%
24 of 34
Appendix C (March 19, 2008)
Table C -26
' Projects Demand During Multiple Dry Year Period Ending 2027
Updated and based on Table 8-17 and Table 8 -20 UWMP
1
Demand
2023
(acre-ft/ r
2024
acre- r
2025
acre- r
2026
acre- r
2027
acre -f l r
Domestic Water Including Conservation
215,331
228 349
231,247
233 388
224,955
Golf Course and Municipal Non-portable
90,100
94,335
94,335
94,816
91,020
Agriculture
305,400
324.5-70
330 684
317,080
Total Demand
610,8321
647.2541
_329,386
654,9681
658,8891
633,055
% of Pro ected Normal Demand
100%1
104.70%1
104.70%1
104.70%
100%
r ..
Appendix C (March 19, 2008)
Table C -27
Projected Multiple Dry Year Demand Ending 2027
Based on Table 8-18 and Table 8 -21 UWMP
1. Modified to reflect 2007 Reliability Report
26 of 34
2023
ac -ft r
2024
ac-ft / r
2025
ac -ft / r
2026
ac -ft r
2027
ac ft / r
.Supply totals
610,832
647.254,
654,968
668.889
633,055
Demand totals
610,832
647,254
654,968
658,889
633,055
Difference Difference as % of Supply
-
-
-
-
Difference as 2.% of Demand
-
-
1. Modified to reflect 2007 Reliability Report
26 of 34
Appendix C (March 19, 2008)
Figure C -1 GW Storage - Normal Year
5 2010 201k 2 0 2025 2030 2
Pro ected Normal (Long Term Avera a Water Year SUPS&
From WSA
- From UWMP
15
Supply Sources
2010
acre- r
2015
(acre-ft/ r
2020
acre- r
2025
(acre- r
2030
(acre-ft/ r)
Groundwater
106,700
123,100
123,700
124 200
123,200
Groundwater Storage 1
13,246
14.065.
-3,774
7,578
3,499
Coachella Canal Water
318,000
342,000
379,000
404,000
429,000
SWP Exchan a Water 2 3
53,335
58,240
55,302
51,188
49,289
Recycled Water
23,100
25,100
26 500
27 600
28,300
Desalinated Drain Water
4,000
8,000
8,000
11,000
11,000
Total Supply
518,381
570 505
588,728
625 566
644,288
15,912 17,211
GW Stora a from UWMP
2010
2015
2020
2025
2030
GW Storage from WSA
13,246
14,065
(3,774
7 578
3 499
GW Stora a from UWMP
4,581
1,7051
18 572
9 334
13 712
Difference (wsa -uwmp)
8,665
12,360
14,798
15,912 17,211
GW Stora a from UWMP
2010
2015
2020
2025
2030
GW Storage from WSA
13,246
14,065
(3,774
7 578
3 499
GW Stora a from UWMP
4,581
1,7051
18 572
9 334
13 712
15,912 17,211
GW Stora a from UWMP
4581
1705
-18572
-9334
-13712
Total Supply
518,3811
570,5 05
588 728
625 566
644 288
GW Storage from WSA
0.9 °�
0.3%
-3.2%
-1.5%
-2.10/-
t
27 0 f 34
15,912 17,211
GW Stora a from UWMP
4581
1705
-18572
-9334
-13712
Total Supply
518,3811
570,5 05
588 728
625 566
644 288
GW Storage from WSA
0.9 °�
0.3%
-3.2%
-1.5%
-2.10/-
M
w
1
Appendix C (March 19, 2008)
1 ' .
Proiactad Normal (Lone Tarm Avaranal Water Yaar Sunniv
Supply Sources
Figure C -2 GW Storage/Total Supply Normal Year
2015
(acre -Wyr)
2015
3.0%
2025
(acre -ft/yr)
2025
2030
(acre -ff/yr)
2030
5 2010 2015 2
2.0%
123,100
123,700
124,200
1.0%
Groundwater Storage 1
13,246
a
CL
-3.774
7.578,
3,499
Coachella Canal Water
0.0%
342 000
From WSA
404.000
429.000
SWP Exchange Water 2 3
5
58,240
-1 0%
51,188
— —From UWMP
w
0
23,100
25,100
26,500
27,600
-2.0%
Desalinated Drain Water
4,000
8 000
8,000
11 000
11,000
Total Supply
-3.0%
570,505
588,728
625,566
-4.0%
Year
Proiactad Normal (Lone Tarm Avaranal Water Yaar Sunniv
Supply Sources
2010
(acre -fttyr)
2010
2015
(acre -Wyr)
2015
2020
(acre -ft/yr)
2020
2025
(acre -ft/yr)
2025
2030
(acre -ff/yr)
2030
5 2010 2015 2
2025 2030 2
123,100
123,700
124,200
123,200
Groundwater Storage 1
13,246
Proiactad Normal (Lone Tarm Avaranal Water Yaar Sunniv
Supply Sources
2010
(acre -fttyr)
2010
2015
(acre -Wyr)
2015
2020
(acre -ft/yr)
2020
2025
(acre -ft/yr)
2025
2030
(acre -ff/yr)
2030
Groundwater
106,700
123,100
123,700
124,200
123,200
Groundwater Storage 1
13,246
14,065
-3.774
7.578,
3,499
Coachella Canal Water
318,000
342 000
379,000
404.000
429.000
SWP Exchange Water 2 3
53,335
58,240
55,302
51,188
49 289
.Recycled Water
23,100
25,100
26,500
27,600
28,300
Desalinated Drain Water
4,000
8 000
8,000
11 000
11,000
Total Supply
518,381
570,505
588,728
625,566
644,288
■
Groundwater Storage UWMP '
4581
2010
-18572
2015
2020
518,3811
2025
588,7281
2030
GW Storage/Total Supply
WSA
2.6%
-3.2 °�
2.5%
" -2.1%
-0.6%
1.2%
0.5%
GW Storage/Total Supply
2.7%
change WSA- UWMP
1.7%
2.2%
2.5%
2.7%
Groundwater Storage UWMP '
4581
1705
-18572
'
Total Supply
518,3811
570,5051
588,7281
6
UWMP
0.9%
0.3 °�
-3.2 °�
-1.5%
" -2.1%
Groundwater Storage UWMP '
4581
1705
-18572
'
Total Supply
518,3811
570,5051
588,7281
6
GW Storage/Total Supply SA
0.9%
0.3%
-3.2%
-9334 -
-13712 '
'
Appendix C (March 19, 2008)
Fig C -3 Precent Difference GW Storage/Total
Supply (WSA -UWMP) Normal Year
3.0%
2.5%
v 2.0%
c -
O
0 1.0%
0.5%
0.0%
2005 2010 2015 2020 2025 2030 2035'
Year
Projected Normal (Long Term Avera a Water Year Supply
Supply Sources
'
2010
acre - r
2015
(acre-ft/ r
2020
acre- r
2025
acre- r
2030
acre- r
Groundwater
106,700
123,100
123,700
124,200
123,200
Groundwater Stora -ge 1
13,246
14,065
-3,774
7,578
3,499
Coachella Canal Water
318.000
342,000
379,000
404.000
429,000
SWP Exchange Water 2 3
53,335
58,240
55,302
51 188
49,289
Recycled Water
23,100
25,100
26, 500
27,600
28,300
Desalinated Drain Water
4,000
8 000
8,000
11 000
11,000
Total Supply
518,381
570!606
588,728
625 566
644,288
' 2
20101 2
20
% Difference WSA -UWMP 1
1.7% 2
2.;
' G
GW Stora elfotal Supply SA 2
2.6%1 2
2.1
GW Stora errotal Supply UWMP) 1 0
0.9% 0
0.;
1 G
Groundwater Storage UWMP 4
4581 1
1705 -
SA 0.9% 0.3% -3.2% -1.5% -11 0A
i�
1
1
- 29 of 34
i�
1
1
- 29 of 34
v.
Fig C-4 GW Storage/Total Supply Single Dry Year
No SWP Water (WSA & UWMP)
o
GW Storage
i
2005 2010 2015' 2020 2025 2030. 2035
Year
18.0 /o
16.0%
a 2' 14.0%
12.0%
10.0%
p 8.0%
C 6.0%
0 4.0%
2.0%
0.0%
Appendix C (March 19, 2008)
Table C -12
Projected Single Dry Year Supply `
Update of Table. 8-4 UWMP
Assumes no SWP deliveries in Single Dry Year '
Supply Sources
2010
(acre-ft/ r
2015
acre- r
2020
(acre-ft/ r
2025 .
(acre-ft/ r
2030
(acre-ft/ r)
Groundwater
106,700
123 100
123,700
124 200
123,200
Groundwater Storage 1
90,945
99 119
79,199
88,168
83,069
Coachella Canal Water
318,000
342,000
379,000
404,000
429,000
SWP Exchan a Water
-
Recycled Water
23,100
26,100
26,500
27,600
Desalinated Drain Water
4 000
-8,000-
8,000
11 000
Total Supply
542 745
597,319
616 399
654,968
g674 fl569
GW Stora e/Total Su I
16.8%
16.6%
12.8%
13.5%
1. Groundwater storage is the difference between demands and supplles. A positive number indicates groundwater pumped
from storage; a negative number indicates water to storage.
Year
20101
20151
20201
20251
2030
GW Storage
90,945
99,1191
79,199
1 88,168
1 83,089.
Total. Supply
542,7451
597,3191
616,3991
654,9681
674.569
GW Storage/Total Supply
16.8%1
16.6%1
12.8%1
13.5%1
12.3%
30 of 34
i
Appendix C (March 19, 2008)
Fig C -5 GW Storage /Total Supply Single Dry Year
No SWP Water
— — SWP per Adv. Del.
Agt
2005 2010 2015 2020 2025 2030 2035
Year
.Table C -13
'Projected Single Dry Year Supply Based on Table 8-4 UWMP
Assumes SWP deliveries during Single Dry Year per Advanced Delivery Agreements
Supply Sources
18.0%
2015
(acre-ft/ r
16.0%
:1,14.0%
2030
acre-ft/ r)
a
12.0%
123,1 OD
10.0%
ers
Fo
8.0%
p
6.0%
95,438
4.0%
84,487
2.0%
Coachella Canal Water
0.0%
No SWP Water
— — SWP per Adv. Del.
Agt
2005 2010 2015 2020 2025 2030 2035
Year
.Table C -13
'Projected Single Dry Year Supply Based on Table 8-4 UWMP
Assumes SWP deliveries during Single Dry Year per Advanced Delivery Agreements
Supply Sources
2010
acre -ft/ r
2015
(acre-ft/ r
2020
acre -ft/ r
2025
acre- r
2030
acre-ft/ r)
Groundwater
106,700
123,1 OD
123,700
124,200
123,200
Groundwater Storage 1
87.766
95,438
75.478
84,487
79,478
Coachella Canal Water
318,000
342 000
379,000
404,000
429,000
SWP Exchange Water 2 3
3,179
3,681
3,721
3.681
3,691
Recycled Water
23,100,
25,100
26,500
27,600
28,300
Desalinated Drain Water
4,0 0
8,000
8,000
11,000
11,000
Total Supply
542,7451
597,319
1 616,399
654 968
674,569
GW Stora errotal Sup ly
1 16.2%
16.0%
' 12.2%
12.9%
11.8%
31 of 34'
No SWP water
SWP water
2010
2015
2020
20251
2030
GW Stora elTotal Supply C -12
16.8%
16.6%
12.8%
13.5%
12.3%
GW Stora errotal Supply C -13
16.2%
16.0%
12.2%
12.9%
11.8%
% Difference WSA -UWMP
-0.6%--
-0.6%
-0.6%
-0.6%
-0.5%
31 of 34'
No SWP water
SWP water
Appendix C (March 19, 2008
Fig C -6 GW Storage /Total Supply Multiple Dry
Years No.SWP Water
a
20.0 /o
18.0%
16.0%
14.0%
Q 12.0%
N 10.0%
ii°- . 8.0%
0 6.0%
4.0%
2.0%
0.0%
-2 0%
Drought in Years 2, 3 & 4
Assumes No SWP Water Deliveries
Ending 2011
Ending 2015
-
-Ending 2020
- -
-Ending 2025
Ending 2027
32 of 34
YEAR
No SWP water
1
2
3
4
5
endin 2011
GW Stora e/Tot al Su I
4.5%
16.8%
17.3%
16.8%
2.1%
endin 2015
GW Stora e/Total Su I
2.1%
16.6%
16.9%
16.4%
2.5%
PTable
endin 2020
GW Stora elrotal Su I
2.2%
16.0%
13.5%
13.2%
-0.6%
endin 2025
GW Stora errotal Su I
-0.2%
13.2%
13.2%
13.3%
1.2%
2027
i GW Storage/Total Su pply
1 0.5%1
13.3%
1 13.5%
13.3% 1
1.2°%
32 of 34
Appendix C (March 19, 2008)
Fig C -7 GW Storage/Total Supply Multiple Dry
Years - SWP Water Per Advanced Delivery
Agreement
Ending 2011
— — Ending 2015
— :
-Ending 2020
Ending 2025
— Ending 2027
•
Assumes SWP deliveries during Multiple Dry Year per Advanced Delivery Agreements
YEAR
Table
1
2
3
4
5
C -15
endin '2011
GW Storage/Total Supply
4.5%
11.8%
12.4%
10.2%
2.1%
C-19
endin 2015
GW Stora efrotal Supply
2.1%
10.1%
10.4%
10.0%
2.5%
C -21
endina 2020
GW Storage/Total Supply
2.2%
9.8%
7.4%
7.1%
-0.6%
C -23
ending 2025
GW Storage/Total Supply
-4.0%
3.5%
3.2%
2.9%
-4.9%
C -25
ending 2027
IGW Storage/Total Supply
0.6%1
8.0%l
8.2%1
8.0%
1.1%
Appendix C (March 19, 2008)
Fig C -8 GW Storage/Total Supply for Year Ending
2025 - WSA SWP Water Per Advanced Delivery
Agreement- UWMP No SWP Water In Drought
16.o °i°
14.0%
12.0%
a 10.0%
N 8.0% !
WSA
6.0%
- -
4.0% -UWMP
w
O
2.0%
0.0% '
-2.0%1) 11 2 3
4.0 °l0 .
Drought in Years 2, 3 & 4
Assumes SWP deliveries during Multiple Dry Year per Advanced Delivery Agreements
WSA Table C -21 endinci 2025
YEAR
83,486
1
2
3
4j
5
GW Stara efrotal Supply
-0.20/6
7.6%
7.8%1
8.1%1
1.3%
GW Stora elrotal Supply
--2.7%1
13.2%1
13.2%1
13.3%
-1.5%
Difference WSA -UWMP 2.5% -5.7% -5.4% -5.2%1 2.8%
1"P Tahla R -1R andinn 7n75
Groundwater Storage
16 124
83,486
1 84 380
86.274
(9.334)
Total Supply
596,096
631,8261
639 540
647 254
625 566
GW Stara elrotal Su I
-2.7%
13.2%
13.2%
13.3%
-1.5%
Supply Sources
2021
acre- r
2022
acre- r
2023
acre- r
2024
(acre-ft/ r
2025
acre- r
Groundwater
123,300
123,300
123,400
123,600
123,700
Groundwater Storage 1
99
47,769
50,103
52,336
8,078
Coachella Canal Water
384.000
389.000
394,000
399,000
404,000
SWP Exchange Water 2 3
54,473
35,617
35,077
34,538
51,188
Recycled Water
26,720
26 940
27,160,
27 380
27,600
Desalinated Drain Water
8,600
9,200
9,800
10,400
11,000
Total Supply
596,096
631,826
639,640
647,254
625,566
GW Stora errotal Supply
-0.2%
1 7.6%
7.8%
8.1%
1.3%
34 of 34
i
RETENTION BASIN CAPACITY TABLE
SITE DEVELOPMENT
AREA
PROPOSED
VOLUME
VOLUME
AREA
(ac.)
DEVELOPMEN
PROVIDED
TYPE
. ft.)
(cu. ft.)
SPA VILLAS
3.06
CONDOMNIUM
kREIQVMD
9,82
20,000
HOTEL/CONFERENCE
15.4
"-C- OMMERC
,47 -, -
"" "
113,500
CENTER EXPANSION
CONDOMINIUM
, = ' `
GOLF VILLAS
5.6
281
00
c-
F
ra�y:n.
f3.
rt \
�s Y'
ntiv(f,
I3 :Y; �sjr:: •�` •
;yr •: •.
rn7F1_�Y i•'• -
F
NOTE:
OFF -SITE DRAINAGE AREAS WERE
DETERMINED USING APPROVED PLANS
ON FILE WITH THE CITY OF LA- QUINTA
AND FIELD REVIEWED(TRACT NO. 14996)
WDROLMY w
HOTEL 11
HOTEL 12
HOTEL 13
HOTEL 14
HOTEL 15
LAND (JQor:/WPMVW8 COVE
MF = CONDOMINIUMS PER RCFC &WCD HYDROLOGY MANUAL
PLATE :D =-5.6 IMPERVIOUS COVER ® 56%
SOL TYPE A
LEGEND
-°�- DRAINAGE BASIN BOUNDARY
SUB -BASIN BOUNDARY
1Q NODE NUMBER 1
(51.5) GROUND ELEVATION l j
- �---�- FLOW DIRECTION
[ PIPE ELEVATION (V
t^�S of �
AC ? . fe3�
C-r
FF*m SITE HYDROLO,0%6" T
l �P
mDs coNs dL T'lN
MORSE • DQKICH • SCHULTZ
79 -799 Old - Avenue 52 (760) 771 -4013
La Quinta, CA 92253 FAX 771 --4073
PLANNING ENGINEERING SURVEYING
I + /41312J1SYDRD SV1;
EXISTR
1 g' - R
�z.r3a„
Q10 = 9.11 CFS
Q10 INT = 7.20
>'
Q10 FLOWBY = 1.
>:
Q100 = 14.51 CFS
Q100 INT = 9.20
rF+ <
Q1oo FLOWBY — 5.
-�
• .
£nor; j
is3,y
.
.` ✓c
r.
'
Y
y
I.
Yat.•ac' f i':di. .
.'
J flx'ti r
Lf iW�4 %aa.•`
0c
s
F
NOTE:
OFF -SITE DRAINAGE AREAS WERE
DETERMINED USING APPROVED PLANS
ON FILE WITH THE CITY OF LA- QUINTA
AND FIELD REVIEWED(TRACT NO. 14996)
WDROLMY w
HOTEL 11
HOTEL 12
HOTEL 13
HOTEL 14
HOTEL 15
LAND (JQor:/WPMVW8 COVE
MF = CONDOMINIUMS PER RCFC &WCD HYDROLOGY MANUAL
PLATE :D =-5.6 IMPERVIOUS COVER ® 56%
SOL TYPE A
LEGEND
-°�- DRAINAGE BASIN BOUNDARY
SUB -BASIN BOUNDARY
1Q NODE NUMBER 1
(51.5) GROUND ELEVATION l j
- �---�- FLOW DIRECTION
[ PIPE ELEVATION (V
t^�S of �
AC ? . fe3�
C-r
FF*m SITE HYDROLO,0%6" T
l �P
mDs coNs dL T'lN
MORSE • DQKICH • SCHULTZ
79 -799 Old - Avenue 52 (760) 771 -4013
La Quinta, CA 92253 FAX 771 --4073
PLANNING ENGINEERING SURVEYING
I + /41312J1SYDRD SV1;
S
i
. i
r
I
1
■
VA
IK
' I. Iiiok;IIBEANQ isFa.! 1
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:I'1rfLl711ID11 ;; Wil 1 =04N17/l ilk FA99=k7lI:
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CITY C>F- 1_A UUIiVTA
PRELIMINARY HYDROLOGY MAP
ENVIRONMENTAL IMPACT REPOI9
k OUINTA RESORT, SPECIFIC PLAN AMEN
Ain A P1 A AIAIIAIr%. A Q= A l