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36875TENTATIVE TRACT NO.36875 HYDROLOGY October 10, 2016 PREPARED FOR: Desert Land Holdings PREPARED BY: gpoFESSI WATSON ENGINEERING 0 50200 MONROE STREET INDIO, CA 92201 No, 26662 760-275-1553 EXP•3'31.,8 O tk� TABLE OF CONTENTS Table of contents Project summary Hydrology Map Infiltration Basin Volume Qio and Qtoo Calculations to Infiltration Basin and Coachella Storm Water Channel Pipe and catch basin hydraulics Percolation Report CVWD letter PAGE 1 2 3 4 5-9 10-20 PROJECT SUMMARY Tentative Tract 36875 is a proposed subdivision of approximately 3.3 acres into sixteen single family residential lots and the construction of sixteen residential homes. The project is located adjacent to the Coachella Storm Water Channel and CVWD has provided a letter allowing discharge of storm water into the channel. Based upon CVWD's letter with conditions, retention of the 100-yr storm on -site is not required. The total site is designed to drain into an infiltration basin, which will include a MaxWell drywell, and the basin is designed to treat the VBMP amount as required by the WQMP. When storm water exceeds the VBMP volume, the storm water will enter a catch basin and is piped to the Coachella Storm Water Channel. Sladden Engineering prepared a report of Percolation/Infiltration testing for the on -site water retention for the proposed retention basin. The report resulted in an infiltration rate of 13.5 inches per hour. A safety factor of three is recommended which results in a percolation rate of 4.50 inches per hour. This report uses a two inch rate for sizing the retention basin and includes 0.1 CFS percolation rate for the drywell. (Maxwell or equivalent) 2 2 a 72 Zo ME � 4�:J� 0 3,128 Slrl llcn L , . � , S,M= LL-% a F /• M V Nr t 1 1 1 y � 1 11 li � tl d •� u J ♦' LL � N 4 IL � z Q O Q z �O o a J O � J 4 U 00 J n 1L O va Ir Ir u z w O to W W LL U Q V.. O � � � � O V � � n as 0 C a�lizi � to 6 REI 1 11 o1 � � � f t t 'Al 4 o p p < CO 0' I t X l 3, t W Ir � � U a � O �1 rw a x � u o r H Z (it J IL > N a tL � z o O u z W m Q W LL w V ac d 4 fl ev v W Qa zw QIx �a 0 p �Ijf cd I1 ti 0 V fi Aj TO ., �100 1000 90 900 80 800 70 700 60 C 600 01 n 50 0 500 V 0 v • 35 w Z. 400 0 c 30 •— 350 E 25 300 _C •E 20 19 .-. 250 H 17 16 t 2 15 •- a .Q f o` 200 J 12 ff�8 150 �, E f 8 7 6 100 5 LIMITATIONS: I. Maximum length =1000' 2. Maximum area = 10 Acres .► Q b -d- Y WO F .Q g 200 N � :� c 100 `O `e c o � r 40 3 20 & v e K Undeveloped Good Cover Undeveloped Fair Cover T!2 Tc 5 --i 6 n err ape O ' .3 ,� 15 Poor Comer w .- �� .2.c 16 .cam• Singx•'Familr 17 E (1/4 cry' Connercia _ 19 {Pav C3 20 o o III a �_ o � C c KEY 0 LµH—Tc--K—Tc� 30 • EXAMPLE E (1) L=550,,H=5.0,K=Single Family(1/4Ac.) 35 Development , Te =12.6 min. (2) L=550', H=5.0',, K= Commercial 40 Development, Tc = 9.7 min. . " 4 RCFC 15. 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Americas Change Product Lines Project Types Specifications GO Individual Products or Lines Infrastructure Growth Global Standards Home I Resource Center / Flow Calculator I Weir Flow Calculator Resource Center Weir Equation Access Solutions Industry Resources At water dopi hs less than 4 inches an inlet grate acts as a weir to irrraming flow and requiran different analysis to determine Government Regulations flow mpadty. The weir equation used Is listed below and it is used to determine how much wnler flown to Ole grate: LEER® Certification 0.3.33 x L x Hx2 Industry Event Calendar L =flew (fills) perimeter of grate whore flrnv is present (ft) Flow Calculator H = depth of water above grate (it) Glossary of Terms Weir Flow Calculator Glossary of Products Website Tour Options: Enter L and H. dick Calculate to sofvt• for 0 (flow) EJ Brand Store Enter Q and H, dick Calculate to siowe for L (grate perimeter) California Transparency Act 'Indicates required field 0 = Flow (ft'/s); L = Perimeter of grate where flow is present (fi):.2R5 •H = Depth of water over grate (ft): 2i Calculate About Us Resource Center Customer Support My Account Stay Covered Company History Government Regulations Contact Us Personal Info Sign up today to receive EJ news updates Innovation Environmental Stewardship LEEO" Cerflfrcailon WebsRaTour Terms & Conditions Privacy Policy Project Lists and Information on special events and Careers EJ Brand Store MORE> offers, MORE> CalllamlaTransparency Act MORE EAfAILADDRESS GO EJ worldwide Copyright O 2016 EJ Group, Inc. All Rights Reserved Resource Center - Flow Calculators - Weir Flow Calculator Page 1 of 1 ,��%►M About Us I Resource Center I Environmental Stewardship I Contact Us Sign In I Register /�1lAwL pQ MyAccount I My Projects MlivA=rJf 1..at� Language: lrgli• t ;�wa�i For the best experience on this site renisler or lop in first. Americas mange Product Lines Project Types Specifications 7 00 Indlvidual Products or Lines Infrastructure Growth Global Standards Home/ Resource Center/ Flow Calculator/ Weir Flow Calculator Resource Center Weir Equation Access Solutions Industry Resources Al waler depths less than 4 inches an inlet grale acts as a weir to inmming now and requires different analysis to determine Government Regulations flow capacity. The weir oquation used is listed below and it is used to deletmine how much water fiovrs to the grate: LEED8 Certlflcatlon Q = 3.33 x L x H'r' Industry Event Calendar Q = flow (n'/s) L = perimeter or grate where lbw is present (A) Flow Calculator H = depth of water above grate (11) Glossary of Terms Weir Flow Calculator Glossary of Products Webslte Tour options: Enter L and H, dick Calculate to solve for O (flow) EJ Brand Store Enter O and H. click Calculate to solve for L (grate perimeter) California Transparency Act 'Indicates required field O = Flow (cols): 11.4 L = Perimeter of grate where flow is present �i[};•y 'H = Depth of waler over grate (it): 1.32 Calculate 0-1 OR I # t, About Us Resource Center Customer Support My Account Stay Covered Company History Government Regulations Contact Us Personal Info Sign up today to receive EJ news updates Innovation LEED -'Certification Terms & Conditions Project Lists and information on special events and Environmental Stewardship Webslte Tour Privacy Policy offers. Careers EJ Brand Store MORE> MORE> California Transparency Act MORE> fEMAILADDREss 1 GO ^ EJ Worldwide Copyright a 2016 EJ Group, Inc. All Rights Reserved ---�`�"rrr,rn'=t���=[ai;r` ►�-+�irx�f�IfYi�}�1f�iiF'�c+'!`hill+i��till�t�Ir�r�F''?Ffi�lsil�r'tirVi�iifiriaFi�etil�:ifr►rnrr' `_`= �Ffllr4r'7f1i15 L 0 o 1 1/2" SOLID STEEL COVER (TRAFFIC or PARKWAY) 21 1/4" �21 1/4„ L L iLLL LL.t4L� L LLLLjL-jL- LiLLLL-LICE L G L[L`L LL LLL L[E ��4,�LLLL ELL - -iLI IYIL L�L LL L LL.L L [F Li-L�[^LL LL L 6 L L L L L L� L LL L 21 1/4" 4_ 21 1/4" 1 1/2 5/8 © C.I PARKWAY GRATE 21 1/4" 21-1 /- 1 1/2" r@ C.I TRAFFIC GRATE 'I 1 /C • 12" High ....... :......... .......... 12"W X 7"H 18" High ...........................13"W X 12"H 24" High ........................... 13"W X 18"H 28" High...........................13"W X 22"H CB1818 SERIES 18" X 18" CATCH BASIN 1 1/2" 18" t28" © STEEL GRATE (TRAFFIC or PARKWAY) . r „ .ye .�� •. w� STEEL FRAME IS OPTIONAL (E) TOP SECTION 1. Steel Traffic Frames W/ Steel TFC Covers Or Steel TFC Grates Are Designed For AASHTO H-20 Wheel Loading, But Are Not Intended For Direct Traffic Installations. 2. Steel Frames W/ Steel Parkway Covers Or Steel Parkway Grates, Are Designed For A Live Load Of 300 p.s.f. 3. Cast Iron Traffic Grates Are Designed For AASHTO H-10 Wheel Loading, But Are Not Intended For Direct Traffic Installations 4. Cast Iron Parkway Grates Are Designed For 300 p.s.f Wheel Loading. 15� p 1 —1 /2" X 1 /4" THK. STEEL FLATBAR 21 c KID 3/8" DIA. STEEL BAR (2 PLACES) 3/4" O.0 (TYP.) (29 PLACES) 21-1/4" O.D PLAN VIEW 1/2"-13NC HEX —HEAD BOLT r 2„ UNISTRUT W/ SPRING NUT 18" X 18" STEEL TRAFFIC GRATE per ADA SPECIFICATIONS 5/8" DIA. HOLE FOR BOLT —DOWN 1 /2 ' DIA. BOLT DETAIL 1. All steel shall conform to ASTM A36. 2. Grate conforms to ADA requirements. 3. Galvanizing is available upon request. 4. Structures are designed for AASHTQ H-20 Wheel Loading. 2 1/4" 2 1/4" 2 1/4" SOLIIJ STEEL COVER (TRAFFIC or PARKWAY) 26 1/4' 1/4" @D C,I TRAFFIC GRATE 1 3/4" STEEL FRAME *Catch Basin Height __ -*Knockout Size 12" High ...........................14"W X 7"H 18" High ............... ............ 14"W X 11 "H 24" High ...........................14"W X 17"H 28" High ................. ..........14"W X 22"H CB2424 SERIES 24" X 24" CATCH BASIN © STEEL GRATE (TRAFFIC or P► 26 1/4" 2 1/4" Y) 26 1/4' > STEEL FRAME IS OPTIONAL QE TOP SECTION 18 2E 1. Steel Traffic Frames W/ Steel TFC Covers Or Steel TI=C Grates Are Designed For AASHTO H--20 Wheel Loading, But Are Not Intended For Direct Traffic Installations. 2. Steel Frames W/ Steel Parkway Covers Or Steel Parkway Grates, Are Designed For A Live Load Of 300 p.s.f. 3. Cost Iron Traffic Grates Are Designed For AASHTO H-10 Wheel Loading, But Are Not Intended For Direct Traffic Installations 4. Cost Iron Parkway Grates Are Designed For 300 p.s.f Wheel Loading, Resource Center - Flow Calculators - Orifice Flow Calculator Page 1 of 1 i %ilti About Us I Resource Center I Environmental Slewardship I Contact Us Sign In I Register (ifOr e My Account I My Projects :�Atri tt��r • Language: ngllsh For the best experience on this site rag star or loa in first. Americas Change Product Lines Project Types Specifications I Go Individual Products or Lines Infrastructure Growth Global Standards Home f Resource Center I Flow Calculator! Orifice Flow Calculator Resource Center Orifice Equation Access Solutions Industry Resources The flow capacity of any inlet grate In a sump orponded condition is a function of the depth of water over the grate and the Government Regulations open area of lha grate. For this calculation, the aririce equation is used. The orifice equation can be used to determine the now though a grate. LEED® Certification Industry Event Calendar a=o.olosxnx:d o = now ("'IS) Flow Calculator A = open area of grate (in') d = depth of water over grate (in) Glossary of Terms Glossary of Products Orifice Flow Calculator Website Tour options: EJ Brand Store Enter A arid d, coati Calculate to serve for O (Raw) Enter O and d, click Calculate to solva for A (grab open area) California Transparency Act *Indicates required field O = Flow (n'/s): 44 y A = Open area of grate (in'): 12Dg.f78 ' d = Depth of water over grate The o&m equation works best with water depths of 4 Indies Calculate cief About Us Resource Center Customer Support My Account Stay Covered Company History Innovation Government Regulations Contact Us Personal Info LEED* Certification Terms 8 Conditions Project Lists Sign up today to receive EJ news updates and Information on special events and Environmental Stewardship Webste Tour Privacy Policy offers. Careers EJ Brand Store MORE> MORE > Californla Transparency Act MORE LMAII ADDRESS GC EJ worldwide Copyright © 2016 EJ Group. Inc. Ali Rights Reserved 1g • -- .._ _...--- ---- ----- ---- '--- ----- —_--- --__ � fir_-�i� .. � _�..... ... 'f� 2" 1 /4" STEEL FLATBAR 3/8" STEEL FLATBAR Steel Galvanized Frame 8"X16" KNOCKOUT TWO IN EACH SIDEWALL 2'-0" X 3'-0" OPEN BOTTOM CATCH BASIN W/ STEEL TRAFFIC GRATE or STEEL PARKWAY GRATE 39-3/8" Painted or Galvanized -Available Upon Request (A� STEEL BOLTDOWN PARKWAY GRATE 39-3/8" Painted or Galvanized t§- '-,,.,--Available Upon Request �j STEEL BOLTDOWN TRAFFIC GRATE © TOP SECTION W/ FLUSH FRAME or 12" U EXTENSION SECTION or 12" 20"X20" KNOCKOUT ONE IN EACH ENDWALL ur O LOWER SECTION 4' Ile **Minimum Excavation: 3'-8"x4'-8"xDepth Req'd NOTES 1. Traffic Grotes Are Designed For AASHTO H-20 Wheel Loading, But Are Not Intended For Direct Traffic Installations. 2. Parkway Grates Are Designed For A Live Load of 300 p.s.f Go Back to Part n Go to Chart 6 v�tle dlkc6n � C:HART 5 sp T 1C8 ' Q,DaO :EXAMPLE I I } Iry 6- 0130` D• 34 i"hot.l'3-0 larl! • _ D0000 0•fir oft - •}71 - _ ;144 a - tool. ow MAW)D . I.iMll 6. jai q (•6� 1.2 C6 J aD is rt J' w. $00 r. — gq , Sao, K 1 400 i I'a Z 20Q 40dz �+4 J 1.0 .^-H I.D In 40 ¢' r .O r-war' '30 11 SCdtE Ek-TRANCE : cc ul •TYPE Ust4ratl 4E S011lf.r.i s� r.:1.►w , 4 r4 sl*fit i .0 1 r s YM Wr'twk $21 ar 131 jrwll=! f use tlrallpm rwirfmmd rtr*r1h ._. ., a ' � •r� --Q rtil� 'i[*1*i, •I'�fvr+4t CF •• .V�• •_, • - :H_EADWAT,.E•R. aEp�T'H FOR YM.:PIPE 'OULVERTS �• - .. 's�r,�iu .. W irif. iNUT CONTROL - • ,. _ cr �r'ue�;.aat.oi ��r'. r7s's . - ., ,. Sladden Engineering 45090 Golf Ccnter Parkway, suite F, lndiu, CA. 92201 (760) 863-0713 1'nx (760) 863-0947 6782 S19211an Avenue. Suilc C. $ucna Park. CA. 9N2) l (714) 523-0952 Fox (714) 523-1369 450 Egon Avenue, 8=umon4 CA. 92223 f951) &15-7743 Fax (951) 845.8863 800 E, l:loridn Avenue, Hemel, CA. 92543 (951) 766-8777 Pax (951) 766-8778 February 16, 2015 Project No. 544-14317 15-02-075 Snellenberger family Investments 75-161 Sego lane, E--3 Palm Desert, California 92211 Project: Proposed Residential Sub -Division Tentative Tract Map No. 36875 SEC Jefferson Street and Palm Circle Drive La Quinta, California Subject: Percolation/Infiltration Testing for On -Site Storm Water Retention Ref: Geote clinical .Investigation Deport prepared by Sladden Engineering dated February 16, 2015; Project No. 544-14317, Report No.15-02-073 As requested, we have performed infiltration/percolation testing on the subject site to evaluate the infiltration potential of the near surface soil to assist in storm water retention system design - It is our understanding that on -site storm %inter retention will be required for the proposed project. Percolation testing was performed on February 32, 2015 within one (1) shallow test bore excavated on t1le site. Testing was performed at a depth of approximately 5.0 feet (.p 1) below existing grade. The appmximate location of the test is presented on the attached Borehole Location Plan (Figure 7). Testing was .performed by placing water within the test bores and recording the drop in the water surface with time. Testing was performed in general accordance with the United States Burean of Reclamation (BOR) Procedure 730Q-89 (1999). Test results are summarized in the following table. Test Number No. P-1 PERCOLATION TEST RESULTS )th (Ft) Infiltration Rate 5.0 135 An infiltration rate of 13.5 in/hr was determined by testing. The percolation rate determined represents an ultimate field rate that does not include a safety factor. An appropriate safety factor should be applied to account for long -terra saturation, subsoil inconsistencies and the potential for silting of the percolating soil. The safety factor should be determined with consideration to Other factors in the storm water retention system design (specifically storm water volume estimates) and the safety factors associated with these design components. We recommend a mininxum safety factor of 3 from a geotechnical perspective. Sladden Engineerritle February 16, 2015 -2- Project No. 544-14317 15-02-075 Groundwater was not encountered within our test hole or within the bores conducted during the preparation of the referenced Geotechnical Investigation. Groundwater should not be a significant consideration in storm water retention system design, If you have any questions regarding this memo, please contact the undersigned. Respectfully submitted, SLADDEN ENGINEERING Principal Engineer Copies: 4 / Addressee v.i'in� nxx Fe xxoin'Wrlun. On-SlteStorm Water Retention Percolation Data Sheet Project TI M I►]a 338875 Project 14317 Test Date Excavated: 2 24-14 Depth of Test Hole: 5 feet _ Soil Classification; SP/SM Check for Sandy Soil Criteria Tested by: Slake Date: 2_ 12-15 Presoak: 2 hours Actual Percolation Tested by: Blake _ Date: 2-12-15 Trial Time Time Initial Final Change in No. of Interval Water Water Water eadinci min. Levelin, Level in. Level n, A :8:45 30 8.5 0.0 8.5 B 30 0.0 11.6 Reading Time Time Total Initial Final Change in Cumulative No. of Interval Elapsed Time Water Water Water Drop Reading (min.) (min.) Level (in.) Level (in_) Level (in.) (ft.) 1 9:15 30.00 30.00 10.50 0.00 10.50 0.88 2 9:45 30.00 60.00 10.00 0.00 10.00 1.71 3 10:15 30.00 90.00 10.00 0.00 10.00 2.54 4 10:45 30.00 120.00 9.00 0.00 9.00 3.29 5 11.15 30.00 150.00 11.00 0.00 11.00 4.21 6 11:45 30.00 180.00 8.00 0.00 8.00 4.88 7 1215 30.00 210.00 11.50 0.00 11.50 5.83 8 12:45 30.00 240.00 11.50 0.00 11.50 6.79 9 1:15 30,00 270.00 10.00 0.00 10.00 7.63 10 11 12 Rate: 13.5 In/hr Sladden Engineering j Borehole Location 131-1-16 4 7 LEGEND 1 0 P-1 Infiltration Test Location -7,; - 1..k. 1, . % . V1 SBH. V W. 1R., :-.22, 4,y I Im 2 J it 47- M 3 101 I - :�N- j• 13 Y1 ­k"NA": M SN L3 -Y q, T 1-2 Tp i E 21 T'J lux r3 L Act ' ffI V'S;L2, D , A I144N-, Uti 9y4 f , 4 i 4 Y. 7� XE Mr gg 41. L T, iti n 'Y" A 7� '?4 x SH 14 43 26 kk x r 4 M TA.DRW.E, ij J!, 7 V BOREHOLE LOCATION PLAN FIGURE Pro ett Number. 544-14317 art N umber. Sladden Engineerumber.15-0-9-WS - I Date. February 16,2015 Established in 191gas a public agency Coachella Valley Water District 7R1 Directors; Aft P. POWd, Jr, President - Div. 3 Peter Nelson, We President- Div. 4 G. PaWk O'Dowd - Div Ed PUa - DIv. 2 Castulok Estrada - Div. 5 December 22, 2015 Wally Nesbit Planning Commission City ofLa Quinta 78405 Calle Tampico La Quinta; CA 92253 Dear Mr. Nesbit: Ofterr Jim Barrett, General Manager Ma Fernandez, Board.secrelary Best Best & Krieger LLP Attorneys File: 0163.1 0421.1 0721.1 1150:14 Geo. .050728-2 PZ 15-6525 Subject: YxIoject No. MP 2015-0 003 Villas at Indian S dg s 'TTM 36875 This letter supersedes the CoachellaValley Water District's (CVWD's) letter dated August 12, 2015. Regional stormwater 'flows within this area are conveyed by the Coachella Valley Stormwater Channel (CVSC). However, this does not guarantee that the land area or the properties will be free from flooding or flood damage. This area is designated Zone X on Federal Flood Insurance rate maps, which are in effect at this time by the Federal EmerMency Management Agency aT A). Flood .protection measures for local drainage.shall l comply with 'California Drainage Law and Provide that stormwater flows are received onto and discharged from this property in a manner 'that is reasonably compatibly with predevelopment conditions, An exception to this is described below. The project i$ located adjacent to a concrete lined portion of the. Coachella Valley Stormwater -Channel (CVSC). The developer may discharge runoff generated from the project site to the CVSC. CVWD requires submittal of storrndrain outlet plan, in accordance With Quideline K4 of the CVWD Development Design Manual, and a hydiaulic:analysis :report.for review to ensure that the outlet will not impact the stability of the CVSC slope protection. In addition, CVWD requires a letter from the City of La Quinta (City) that certifies that discharge into the CVSC• meets all .MS4 permit requirements, including requirements for the Water Quality Management Plan and Best Management 'Practices., �d D.EC22 �06 Wally Nesbit City of La Quinta 2 December 22, 2015 A Portion of this area is adjacent to the right-of-way of the CVSC. The developer shall be required to install suitable facilities to prohibit access to this right-of-way. The developer shall obtain .an.Encroacb cm Permit from Coachella Valley Water District (CVWD) prior to any activity within the rght-of--way of the CVSC. The project, is located within the service area of CVWD for the provision of domestic water and sanitation service. The initiation of said service to this area will be subject to the satisfaction of terms and conditions established by CVWD and 'unposed from time to time, including but not limited to fees and charges, water conservation measures, etc. CVWD may need additional facilities to provide for the orderly expansion of its domestic water and sanitation systems. These facilities may include pipelines, wells, reservoirs, booster pumping stations, lift stations, treatment plants and other facilities. The developer may be required'to construct/h stall these facilities and then convey said facilities to CVWD along with the ]arid and/or easements on which these facilities will be located. The terms and. conditions for the planning, desigN construction/installation; and conveyance of property interests shall be determined. by CVWD pursuant to its rules and regulations as said requirements may be revised fxom time to time. These sites sW be shown on the tract map as lots and/or easements to be deeded to CVWD for "CVWD public services"purposes. This notice of domestic water and sanitation service availability only applies to the .specific property for which it was issued and shall expire three (3) y from date of issuance. Unless or until all requirements for -the initiation .of service are met, the developer shall not be deemed to have.any vested right or other commitment to receive water and/or sanitation service. In. the event all of the terms, conditions, fees and charges are not satisfied on or before the expiration date, this notice shall expire. Upon expiration, the developer will be required to submit a new application and otherwise comply with any and all new or.amended requirements.for the Provision of service as may be determined by CVWD pursuant to its rules and regulations. Domestic water and sanitation service remains at all times subject to.changes in regulations adopted by -CV WD's Board. of Directors including reductions in, or suspensions of -service. This development is subject t6 the City's Landscape Ordinance which was adopted in accordance with the State's Model Water Efficient Landscape Ordinance and CVWD's Ordinance 1302.1. The purpose of these ordinances is to establish effective water efficient.landscaping requirements for newly installed and rehabilitated landscapes..In order to ensure this development's compliance, plans for -,grading, landscaping and irrigation systems shall be submitted to CVWD for review priorto installation. This review is untended to promote efficientwater. management. However, by reviewing the plans, CVWD does not represent or warrant zany amount of water or financial savings. Wally Nesbit City .of La Quinta 3 December 22, 2015 Ile project lies within the East Whitewater River Subbasin Area of Benefit. Groundwater Production within the area of benefit is subject to a replenishment assessment in accordance with the State Water Code. All water wells owned or operated by an entity producing more than 25 acre-feet of water during any year must be equipped with a water -measuring device. A CVWD Water Production Metering Agreement is required to provide CVWD:staffwith the authority to regularly read and maintain this water -measuring device. This development lies within the study area of the 2010 Water Management Plan Update. The groundwater basin in the Coachella. Valley is in a state of overdraft.. Each new development contributes incrementally to the overdraft. CVWD has a Water Management Plan in. place to reduce the overdraft to the groundwater basin,. The elements of the 'Water Management Plan include supplemental imported water, source substitution and water conservation. The plant lists specific actions for reducing overdraft. The elements and actions described in the plan shall be incorporated into the design of this development to reduce its.negative impact on the Coachella Valley groundwater basin. If you have any questions, please call Tommy Fowlkes, Development Services Supervism, and extension 3535. Sincerely, Nabbpkafl+ Carrie Oliphant Assistant Director of Engineering cc: Mark Abbott Supervising Environmental Health :Specialist Riverside County Department of Environmental.Health Environmental Protection and Oversight Division 47-950 Arabia Street, Suite A Indio, CA 92201 Desert Land Holdings, LLC 75-161 Sego Lane, E-3 .Palm Desert, CA 92211 TD: nNXEng1SW120i5Me&WiNas'Indian Sp ings ec: Tommy Fowlkes Patti Reyes Teske Demissie Rubea ontiel TD: BLAE019%W120150mWillas Indian Springs