2022-04-26 Vaughn, James Supplemental Noise MemosFrom: Consulting Planner
Sent: Tuesday, April 26, 2022 7:58 AM
To: Tania Flores
Cc: Cheri Flores; Danny Castro
Subject: Fw: Supplemental Noise Memos
Attachments: CM Resort Noise Memo_042522.pdf; 12642-16 Noise Memo.pdf
Tania,
Please distribute to the Commission (printed on the dias or PDF ahead of the meeting), please.
Nicole Sauviat Criste
Consulting Planner
City of La Quinta
From: James Vaughn <JVaughn@szrlaw.com>
Sent: Tuesday, April 26, 2022 7:28 AM
To: Consulting Planner <ConsultingPlanner@laquintaca.gov>; Cheri Flores <clflores@laquintaca.gov>
Cc: Nicole Criste (Contract Planner) <ncriste@Terranovaplanning.com>; John Gamlin
<jgamlin@coralmountain.com>; Tony Locacciato - Meridian Consultants LLC
(tlocacciato@meridianconsultantsllc.com) <tlocacciato@meridianconsultantslIc.com>; Witherspoon,
Michelle<mwitherspoon@msaconsultinginc.com>; Lee, Asia <alee@msaconsultinginc.com>
Subject: Supplemental Noise Memos
EXTERNAL: This message originated outside of the City of La Quinta. Please use proper judgement and caution
when opening attachments, clicking links or responding to requests for information.
Hi Nicole and Cheri,
Per your request, attached are two supplemental noise memos. The first is from Tony Locacciato at
Meridian Consultants, who is responsible for the noise monitoring for the Coachella and Stagecoach
music festivals. The other is from Bill Lawson at Urban Crossroads, who prepared the noise study for the
Coral Mountain Resort project. These memos provide further substantial evidence to support the
conclusion that the project will not have any significant noise impacts.
Please include these in the administrative record of proceedings for the Coral Mountain Resort project,
and please confirm that you received these documents.
Thanks,
Jim
SSA
James D. Vaughn, Esq.
Stowell, Zeilenga, Ruth, Vaughn & Treiger LLP
jvaughngszrlaw.com I www.szrlaw.com
Office: 805.446.1496 I Direct: 805.446.7609 I Mobile 805.551.0688
4695 MacArthur Court
Suite 200
Newport Beach, CA 92660
4590 East Thousand Oaks Blvd.
Suite 100
Westlake Village, California 91362
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From: Consulting Planner <ConsultingPlanner@laquintaca.gov>
Sent: Sunday, April 24, 2022 9:43 AM
To: James Vaughn <JVaughn@szrlaw.com>; Cheri Flores <clflores@laquintaca.gov>
Cc: Nicole Criste (Contract Planner) <ncriste@Terranovaplanning.com>; John Gamlin
<jgamlin@coralmountain.com>; Tony Locacciato - Meridian Consultants LLC
(tlocacciato@meridianconsultantslIc.com) <tlocacciato@meridianconsultantslIc.com>; Witherspoon,
Michelle <mwitherspoon@msaconsultinginc.com>; Lee, Asia <alee@msaconsultinginc.com>
Subject: Re: Indio Subbasin Ground Water Management Documents
Jim,
We have received your email and downloaded the documents. They will be included in the
administrative record for the project.
Nicole Sauviat Criste
Consulting Planner
City of La Quinta
From: James Vaughn <JVaughn@szrlaw.com>
Sent: Saturday, April 23, 2022 1:10 PM
To: Consulting Planner <ConsultingPlanner@laquintaca.gov>; Cheri Flores <clflores@laquintaca.gov>
Cc: Nicole Criste (Contract Planner) <ncriste@Terranovaplanning.com>; John Gamlin
<jgamlin@coralmountain.com>; Tony Locacciato - Meridian Consultants LLC
(tlocacciato@meridianconsultantslIc.com) <tlocacciato@meridianconsultantslIc.com>; Witherspoon,
Michelle <mwitherspoon@msaconsultinginc.com>; Lee, Asia <alee@msaconsultinginc.com>
Subject: FW: Indio Subbasin Ground Water Management Documents
EXTERNAL: This message originated outside of the City of La Quinta. Please use proper judgement and caution
when opening attachments, clicking links or responding to requests for information.
Hi Nicole and Cheri,
Here is a link to five important documents concerning the Indio Subbasin and the ongoing groundwater
management efforts of CVWD and the other Indio Subbasin Groundwater Sustainability Agencies
(GSAs). We request that you download and include in the administrative record for the Coral Mountain
Resort project, the following five documents:
1. Coachella Valley RUWMP- 2021
2. CVWD Water Supply Assessment Fact Sheet
3. Indio-SGMA-Alternative Plan- Compiled- FINAL Adopted Dec. 2021
4. Indio-Subbasin Annual Report Workshop- March 22 Final
5. Indio-Subbasin WY- 2021 Final
https://www.dropbox.com/scl/fo/gcx5fvdylg33zob316r4f/h?d1=0&rlkey=8abfyglm7yxyo67ykelvm0lyv
These documents contain important facts regarding some of the comments recently made by LRRD and
other members of the public regarding the sustainability of the Indio Subbasin, including:
(1) Since 2009, the amount of water stored in the subbasin has increased by approximately 840,000
acre-feet through the groundwater management efforts of these GSAs despite the fact that the western
United States experienced extreme drought conditions between 2013 and 2016 that led to mandatory
water use restrictions and drastic cuts in deliveries of State Water Project water (see Indio Subbasin Plan
Update page ES-4);
(2) Between 2020 and 2045, the amount of groundwater in the Indio Subbasin is expected to increase
further, even after accounting for the Coral Mountain Resort project and all other existing users and
planned future growth in the Coachella Valley, and after accounting for the effects of climate change
and further extreme drought conditions, as well as planned groundwater management efforts (see Indio
Subbasin Plan Update page ES-12 and Figure ES-8);
(3) The Indio Subbasin SGMA Alternative Plan Update does not assume that more water will be
delivered to California in future years, but rather, takes into account that through existing water transfer
agreements, slightly more of the Colorado River water delivered to California will be allocated to CVWD
(see Indio Subbasin Update pages 6-8 — 6-10 and Table 6-3); and
(4) This Alternative Plan Update also assumes the worst case scenario under the Colorado River Lower
Basin Drought Contingency Plan, whereby CVWD will be required to contribute a portion of its allocated
Colorado River water so it will remain in Lake Mead; and assumes that only 45% of the State Water
Project allocation will be delivered, which is more conservative than the assumptions made by the
California Department of Water Resources (see Indio Subbasin Update pages 7-43 — 7-44).
Please confirm that you are able to access and download these important documents, and that they will
be included in the administrative record for this project.
Thank you for your assistance and please let me know if you have any questions.
Best,
Jim
James D. Vaughn, Esq.
Stowell, Zeilenga, Ruth, Vaughn & Treiger LLP
ivaughn@szrlaw.com 1 www.szrlaw.com
Office: 805.446.1496 1 Direct: 805.446.76091 Mobile 805.551.0688
4695 MacArthur Court
Suite 200
Newport Beach, CA 92660
4590 East Thousand Oaks Blvd.
Suite 100
Westlake Village, California 91362
IVJeridian
Consultants
LOS ANGELES
706 S. Hill Street, 11th Floor
Los Angeles, CA 90014
(213) 335-3434
MEMORANDUM
WESTLAKE VILLAGE
920 Hampshire Road, Suite A5
Westlake Village, CA 91361
(805) 367-5720
Date: April 25, 2022
To: Nicole Criste, Contract Planner, City of La Quinta
From: Tony Locacciato, AICP, Partner
Subject: Coral Mountain Resort Environmental Impact Report Noise Analysis
This memo provides information in response to questions from community members on how the noise that would
be generated by the wave basin in the proposed Coral Mountain Resort Project compares to noise generated by
the ongoing Coachella and Stagecoach Music Festivals, held annually over three consecutive weeks in April at the
Empire Polo Club in Indio, approximately 4.5 miles northeast of the Coral Mountain Project site. The Empire Polo
Club is located between Avenues 50 and 52 and east of Madison Street.
The City of Indio prepared an Environmental Impact Report (EIR) for the Music Festivals Plan Project, certified in
2013, to support the issuance of a long-term permit for these music festival events. This EIR includes analysis of
the sound systems used at these outdoor music festivals and the level of noise experienced by the surrounding
community.
The most notable noise source associated with these events is from the sound systems for each of the multiple
concert stages. Noise monitoring of the 2012 Music Festivals was conducted and noise modeling was prepared
based on configuration of the speakers used at each stage. This analysis determined the primary source of noise
was from the main stage and for this reason, computer modeling of the sound system was completed that served
as the basis for the noise analysis in the EIR. The sound system for the large outdoor main stage consists of a series
of hanging loudspeaker arrays on either side of the stage along with loudspeakers mounted on the stage deck,
and delay loudspeaker arrays set up in front of the stages. This sound system is designed and operated to produce
a sound level of 105 dBA at the front of house (FOH) equipment area where music is mixed for the audience. The
FOH is located approximately 150 feet from the front of the main outdoor stage.
Attached are two figures from the Music Festivals Plan EIR that show the sound levels from the modeling for the
Coachella and Stagecoach Music Festivals. The festival grounds are configured differently for the Coachella Music
and Arts and Stagecoach Country Music Festivals with the main stage located along Avenue 50 and oriented to
the south for the Coachella Festival and along Monroe Street and oriented to the west for the Stagecoach Festival.
As shown in these figures, sound levels of 69 dBA and above are largely contained on the festival site, located
between Madison Street, Avenue 50, Monroe Street, and Avenue 52. Noise levels above 50 dBA are experienced
Page 2
Coral Mountain Resort EIR Noise Analysis
east of Jefferson Street and north of Avenue 54. The City of Indio conducts noise monitoring during these events
at 6 locations around the edge of the festival site during these events. The maximum 10-minute average noise
level along Madison Avenue between Avenues 50 and 52 during the first weekend of the Coachella Music Festival
this year was approximately 75 dBA.
The noise sources and levels generated by the sound system at the main stage at these festivals are not
comparable to the noise sources and levels associated with proposed wave basin, as documented in the Coral
Mountain Resort Final EIR. As described above, the outdoor sound system at the main stage generates a sound
from the large speaker arrays hung above the stage of approximately 105 dBA at a distance of 150 feet from the
stage. Depending on local atmospheric conditions, including air temperature and wind, sound from the festival
sound system may be heard miles away from the festival site.
Noise monitoring was conducted at the Surf Ranch in Lemoore, California in April 2020 and August 2021, as
presented in Appendix K.3 to the Coral Mountain Resort Final EIR to determine the level of noise generated by
this wave basin. The highest measured noise level from the cable roller system that pulls the foil that generates
the wave, and movement of water in the basin, was 75.7 dBA Leq at a distance of 12 feet from the wave basin,
which equates to a noise level of 63.3 dBA at a distance of 50 feet.
To understand how sound levels reduce over distance, as explained in Chapter 5 of the Noise of the Occupational
Safety and Health Administration Technical Manual, as a principle of physics, sound pressure levels decrease by 6
dB, on a Z-weighted (i.e., unweighted) scale, each time the distance from the point source is doubled. This is a
common way of expressing the inverse -square law in acoustics as shown below:
For example, as shown above, if a point source produces a sound pressure level of 90 dB at a distance of 1 meter,
the sound pressure level is 84 dB at 2 meters, 78 dB at 4 meters, and so forth. This principle holds true regardless
of the units used to measure distance.
The noise analysis of the proposed wave basin in the Coral Mountain Resort EIR was prepared using a 3-
dimensional noise model that takes into account changes in topography, walls and other features that will affect
Page 2
Coral Mountain Resort EIR Noise Analysis
noise transmission. This analysis determined the highest level of noise level from the wave basin, approximately
51 dBA, would be at the home located approximately .2 miles east of the wave basin on Calle Conchita.
Exhibit A, attached, presents a comparison of the noise levels generated by the Indio Music Festivals sound system
and the proposed wave basin by distance based on the inverse -square law in acoustics.
For comparison purposes, the noise level generated by the sound system at the main stage at the Indio Music
Festivals of 105 dBA at a distance of 150 feet would be approximately 63 dBA at a distance of 3.6 miles, 57 dBA at
a distance of 7.3 miles, and 51 dBA at a distance of 14.5 miles from the festival site. As described above, the
festival site is located approximately 4.5 mile from the Coral Mountain Resort Project Site. Sound levels from the
sound system at the festival would be between 57 and 63 dBA at the Coral Mountain Resort Project Site and in
surrounding areas of La Quinta. As shown in the comparison in Exhibit A, the sounds levels from the proposed
wave basin would be lower in the area surrounding the Coral Mountain Resort Project Site, with the noise from
the basin being reduced to less than 40 dBA at a distance of 800 feet from the wave basin.
In conclusion, the level of noise generated by the wave basin is not comparable to the noise generated by the
sound system at the music festivals in Indio. The type of sound generated by the wave basin does not include the
broad frequency of sound generated by the music festival sound system, would be generated at ground level, as
opposed to being generated above ground level, and would generates a much lower sound level than the sound
system used at the music festivals.
Desert
1000 2000
APPROXIMATE SCALE IN FEET
4000
yr
�:'
�� .4
Legend
Festival Site
Areas not in
{'5" Festival Site
Sound Levels - dbA
(by color)
Red >99 dbA
Light Orange >87 dbA
Yellow >81 dbA
Dark Green >69 dbA
>50 dbA
SOURCE: L-Acoustics - 2012; Google Earth - 2012
FIGURE 4.4-8
Meridian
C nste/#ants
Existing Festivals — 2012 Coachella Sound Levels
002-001-12
Desert
1000 2000
APPROXIMATE SCALE IN FEET
4000
yam
Legend
Festival Site
Areas not in
{'5" Festival Site
Sound Levels - dbA
(by color)
Red >99 dbA
Light Orange >87 dbA
Yellow >81 dbA
Dark Green >69 dbA
>50 dbA
SOURCE: L-Acoustics - 2012; Google Earth - 2012
FIGURE 4.4-9
Meridian
C nste/#ants
Existing Festivals — 2012 Stagecoach Sound Levels
002-001-12
EXHIBIT A - INDIO MUSIC FESTIVAL AND WAVE BASIN SOUND LEVELS BY DISTANCE
INDIO MUSIC FESTIVAL SOUND LEVELS WAVE BASIN SOUND LEVELS
dBA Noise Level Distance in Feet Distance in Miles
dBA Noise Level Distance in Feet Distance in Miles
105 150 0.0 63.3 50 0.0
99 300 0.1 57.3 100 0.0
93 600 0.1 51.3 200 0.0
87 1,200 0.2 45.3 400 0.1
81 2,400 0.5 39.3 800 0.2
75 4,800 0.9 33.3 1,600 0.3
69 9,600 1.8 27.3 3200 0.6
63 19,200 3.6 21.3 6,400 1.2
57 38,400 7.3 15.3 12,800 2.4
51 76,800 14.5 9.3 25,600 4.8
45 153,600 29.1 3.3 51,200 9.7
0 URBAN
CROSSROADS CROSSROADS urbanxroads.com
April 26, 2022
Mr. Garrett Simon
CM Wave Development LLC
2440 Junction Place, Suite 200
Boulder, CO 80301
SUBJECT: THE WAVE AT CORAL MOUNTAIN LQRRD RESPONSE TO COMMENTS
Dear Mr. Garrett Simon:
Urban Crossroads, Inc. is pleased to submit this summary of the La Quinta Residents for Responsible
Development (LQRRD) response to the comments related to noise.
1. The comment was made that when you double the distance from a noise source, you drop 6
decibels of sound. 1 would certainly like to reference this weekend's Coachella Fest. If sound truly
drops off like this, why do we hear the music from Coachella all over town.
Section 2.3 of the Coral Mountain Specific Plan Noise Impact Analysis (NIA) describes the sound
propagation, or the way noise reduces with distances. As discussed in the NIA, the way noise
reduces with distance depends on type of noise source (stationary point source, or line source),
the ground absorption, atmospheric effects and shielding. For noise analysis purposes, sound
levels are commonly assumed to attenuate (or decreases) at a rate of 6 dB for each doubling of
distance from a point source and at a rate of 3 dB for each doubling of distance from a line source.
The noise levels associated with the Coachella Fest are vastly different in both frequency content
and source levels than those expected with the wave basin/wave machine activity for the
proposed The Wave at Coral Mountain Project.
It is also important to recognize that NIA demonstrates that the operational noise levels
associated with The Wave at Coral Mountain Project will satisfy the City of La Quinta daytime
exterior noise level standards with no planned nighttime operational noise source activity. This
does not suggest that the wave basin/wave machine activity will be inaudible at times, only that
the Project will not result in significant noise level increase above the existing ambient noise
conditions.
2. The effect of the starting of the machinery to generate the wave on Coral Mountain was not
studied. Also, with the bi-directional nature of the wave, no impact of wave noise going back
against Coral Mountain was even considered. And the sound is generated for up to a 'z mile. It is
not a "point" sound, but a "line" sound.
This statement is factually incorrect. As described in Section 10.1.1 of the NIA, Urban Crossroads,
Inc. collected reference noise level measurements at eight different locations around the Surf
Ranch. The reference noise levels describe the peak noise events associated with all the noise
source activities including, wave announcements over the public address system, move of the
wave sled through the lagoon, mechanical equipment buildings, in addition to cable and metal
12642-16 Noise Memo
Mr. Garrett Simon
CM Wave Development LLC
April 26, 2022
Page 2 of 3
rollers. However, based on our observations, the primary noise source is simply the movement
of water from each wave in the lagoon. The noise analysis describes the wave basin/wave
machine activity as an area source and not as a single line or point source. The area source type
is used to ensure that noise source from the entire wave basin/wave machine is included in the
analysis. These actual noise readings were then used to evaluate projected noise levels at the
Coral Mountain project site using a 3-dimensional noise prediction model that considers changes
in topography, walls and other features that affect noise transmission.
Coral Mountain and the desert land between the wave basin and Coral Mountain are considered
a soft surface that will likely absorb rather than reflect noise back towards sensitive receiver
locations. The direct line of sight between the noise source and the receiver is the primary path
of sound transmission that was considered in the Coral Mountain Specific Plan Noise Impact
Analysis. Field studies conducted by the FHWA have shown that the reflection from barriers and
buildings does not substantially increase noise levels (1). If all the noise striking a structure was
reflected back to a given receiving point, the increase would be theoretically limited to 3 dBA.
Further, not all the acoustical energy is reflected back to same point. Some of the energy would
go over the structure, some is reflected to points other than the given receiving point, some is
scattered by ground coverings (e.g., grass and other plants), and some is blocked by intervening
structures and/or obstacles (e.g., the noise source itself). Additionally, some of the reflected
energy is lost due to the longer path that the noise must travel. FHWA measurements made to
quantify reflective increases in traffic noise have not shown an increase of greater than 1-2 dBA;
an increase that is not perceptible to the average human ear.
3. The other thing we would like to respectfully request for the Commissioners to review is the
document we included in your packet "Surf Wave Parks — Assessing the Sound of Fun". Airborne
generation of noise from breaking waves has been shown to be complex, containing tonal,
modulating and broadband components, which are all additive when assessing noise dose. These
sounds are the Low Frequency Sounds we discussed in our presentation that travel long distances
and need to be evaluated when placed in environmentally sensitive areas. With the way the surf
basin is situated, and that there would be 50 hertz frequencies in the "C" range generated by the
surf.
This memo supports our findings that the primary noise source is simply the movement of water
from each wave in the lagoon. In addition, the City of La Quinta has adopted the A -weighted
frequency response to control community noise impacts. A -weighted decibels (dBA)
approximate the subjective response of the human ear to broad frequency noise source by
discriminating against very low and very high frequencies of the audible spectrum. They are
adjusted to reflect only those frequencies which are audible to the human ear. Although the A -
Weighted response is used for most applications, C-Weighting is usually used for Peak
measurements and in some entertainment noise measurement, where the transmission of bass
noise can be a problem.
12642-16 Noise Memo
`�► URBAN
CR055ROADS
Mr. Garrett Simon
CM Wave Development LLC
April 26, 2022
Page 3 of 3
A review of the unweighted (Z) spectral content of the reference noise level measurements
shows a level of 54.0 dB at 50 hz with most of the noise content in the range of 500 to 1000 hz
of 63.9 dB. The unweighted (Z) frequency content of the reference noise level measurements
does not support the use of the C-Weighting.
4. Until further evidence of noise generated from such parks is available, control of such noise will
be difficult to evaluate, and authorities should demonstrate caution when assessing such
proposals placed in noise sensitive areas.
The evidence shows that wave basin/wave machine will satisfy the City of La Quinta daytime
exterior noise level standards. In addition, the NIA demonstrates that the Project will contribute
a less than significant operational noise level increase to the existing daytime ambient noise
environment at all existing off -site receiver locations.
Respectfully submitted,
URBAN CROSSROADS, INC.
Bill Lawson, P.E., INCE
Principal
12642-16 Noise Memo
URBAN
CROSSROADS