Department of Public Works, Los Angeles County - …...August 2016 4.G. Hydrology and Water Quality Los Angeles County Department of Public Works Harbor‐UCLA Medical Center Campus

LosAngelesCountyDepartmentofPublicWorks Harbor‐UCLAMedicalCenterCampusMasterPlanProjectSCH#2014111004 4.G‐1

4.0 ENVIRONMENTAL IMPACT ANALYSIS G. HYDROLOGY AND WATER QUALITY

1. INTRODUCTION

Thissectiondescribes theaffectedenvironmentandregulatory frameworkassociatedwithhydrologyandwaterqualityontheHarbor‐UCLACampusandintheProjectvicinity.Italsodescribesimpactsonhydrologyandwaterqualitythatwouldresultfromimplementationoftheproposedproject.SinceplansforbuildoutoftheMasterPlanProjectarepresentlyconceptual,analysisanddeterminationofpotentialimpactsarebasedonthegeneralconceptandlayoutdescribedinSection2.0,ProjectDescription,ofthisDraftEIRratherthanadetailed, fixedplan. Information in thissection isbasedondocuments includingtheHarbor‐UCLAMasterPlan(2012),LosAngelesCountyGeneralPlanUpdate(2015)andassociatedEIR(2015).

2. ENVIRONMENTAL SETTING

a. Surface Water Quality

TheProject site iscurrentlydevelopedwitha72‐acreMedicalCenterCampuswhich includes theHarbor‐UCLAMedicalCenterandthreeothermajortenants;LABioMed,thelargesttenant,theHarbor‐UCLAMedicalFoundation, Inc., and the Children’s Institute International. A number of other County departments,includingofficesoftheDepartmentofMentalHealth,occupybuildingsontheMedicalCenterCampus.Landcover on‐site consists primarily of buildings and pavement with limited and discontinuous landscapinglocated throughout the campus. Land uses at the site include a mix of commercial, transportation,institutional and landscape. Land uses around the medical center include commercial uses, primarilyneighborhood retail businesses andmedical/dental services. TheHarbor‐UCLAMedical CenterEmployeeChildren’sCenterandamultifamilyresidentialapartmentcomplexare locatedonCarsonStreet. Theareanorth of Carson Street is a predominantly single‐family residential neighborhood. Vermont Avenue isdevelopedwithamixofneighborhoodretailusesandmedicalservicesjustnorthandsouthofCarsonStreet,while the southern half of the block is developedwith a condominium complex andmobile home parks.Wholesaleandlightindustrialuses,primarilywarehousesandtruckdistributioncenters,arelocatedtothesoutheast. Single‐familyandmulti‐familyresidentialneighborhoodsbordertheMedicalCenterCampustothesouthaswellastothewest.TheabandonedUnionPacificRailroadright‐of‐wayareaalongthewestsideofNormandieAvenue serves as a setback for residentialuses to thewest. Anoff‐site surfaceparking lotservingLABioMedislocatedacross220thStreetfromtheMedicalCenterCampus.

TheProjectsitedoesnotappeartoincludewaterqualityorStormwatercontrols,suchasStormwaterBMPs,LID features, or hydromodification management facilities. According to the Harbor‐UCLA Master Plan,previouslyapproveddrainageplansfortheemergency/surgeryreplacementindicatethatseveraldrywellsare utilized in the new development area. Rainfall and stormwater runoff on‐site are managed by roofdrains, catch basins, drain inlets, underground pipes, curbs, gutters, overland sheet flows, driveways, orothermeansofconveyancetotheon‐sitestormdrainsystem.

4.G. Hydrology and Water Quality August 2016


(1) Stormwater Runoff (Typical Pollutants from Project Site)

Stormwater runoff from the Project site is typical of urbanized areas and includes pollutants frommotorvehiclesandothertransportationrelateduses(parking lots). Pollutants includehydrocarbons,oil,grease,sedimentandheavymetals.PollutantsassociatedwithlandscapemaintenancearealsolikelytobepresentinStormwaterrunoff.Thesepollutantsincludenutrientsfromfertilizersandherbicidesandpesticides.Asthe site is a medical center, and has a high volume of visitors, trash is also expected to be a potentialpollutant. FecalcoliformbacteriaandotherpollutantsaretypicallyfoundinStormwaterrunoff fromlandusessimilartothoseatthesite.

Landscaping throughout the Medical Center Campus is limited and discontinuous. There are severallandscaped courtyards, predominantly at the western end of the Campus, surrounding the MFI and CIIbuildings, and on the LA BioMed Campus, and in scattered locations in the north‐central Campus. Inaddition,themainentrancetotheHospitalonCarsonStreetisplantedwithmaturetrees,shrubs,andalawnsetback.TheVermontAvenuefrontage,adjacenttothenewparkingstructureandHospitalparkinglot,andthecorneroftheCampusatCarsonStreetandVermontAvenue,arethemostheavilylandscapedportionsoftheMedicalCenterCampusperimeter,withmaturetreesandalandscapesetbackfromthesidewalk.

Table4.G‐1,PollutantsofConcernbyLandUse,summarizestypicalpollutantsofconcernaccordingtolanduse.ThemajorityofthepollutantslistedarefromtheFebruary2014CountyofLosAngelesDepartmentofPublicWorksLow‐ImpactDevelopmentStandardsManual. OtherpollutantstheEPArecognizesastypicallyassociatedwiththelandusespresentontheProjectsitearealsoincludedinthetable.

(2) Pollutants of Concern Based on Receiving Water Impairment

TheProject site is locatedwithinRegion4 (LosAngelesRegion)of theRWQCB. TheLosAngelesRegionencompasses all coastal drainages flowing to the Pacific Ocean between Rincon Point (on the Coast ofWesternVenturaCounty)andtheeasternLosAngelesCounty line,aswellas thedrainagesof fivecoastalislands(Anacapa,SanNicolas,SantaBarbara,SantaCatalina,andSanClemente).Theregionalsoincludesallcoastalwaterswithinthreemilesof thecontinentalandislandcoastlines. TheProjectsite fallswithintheDominguezWatershedwhichencompasses approximately133squaremiles in southwesternLosAngeles;120squaremilesislandandtherestistheLosAngeles/LongBeachHarbors.Thewatershediscomposedofthreesubwatersheddrainageareas;UpperDominguezChannel,LowerDominguezChannelandEstuary,andLosAngelesandLongBeachHarborsincludingMachadoLake1. Thesubwatershedsdrainprimarilyviaanextensivenetworkofundergroundstormdrains.TheUpperDominguezChanneldrainsintotheDominguezChannelwhile theLowerDominguezChanneldrainsdirectly intotheLosAngelesandLongBeachHarborArea. The headwaters of the Dominguez Channel consist of an underground storm drain system whichdaylights approximately 0.25 miles north of the Hawthorne Municipal Airport. The Dominguez Channeldrains approximately 62percent of thewatershedbefore discharging to LosAngelesHarbor. Within thewatershed,approximately93percentof the land isdeveloped. Residentialdevelopmentcoversnearly40percentofthewatershedwithanother41percentiscoveredwithindustrial,commercial,andtransportation

1 Dominguez ChannelWatershed Management Area Group, 2014. Draft Coordinated Integrated Monitoring Program For The

Dominguez Channel Watershed Management Area Group. http://www.waterboards.ca.gov/losangeles/water_issues/programs/stormwater/municipal/watershed_management/dominguez_channel/DominguezChannel_CIMP.pdf,accessed12/12/15.

August 2016 4.G. Hydrology and Water Quality


uses.Withapopulationofnearlyonemillion,watersupplyislimitedandthemajorityofwateruseisfromimportedsources.

Thereareseveralpollutantsofconcernrelatedtothereceivingbodyofwater.TheProjectsiteislocatedinthelowerDominguezChannelandEstuarysubwatersheddrainagearea.Waterqualityinthewatershedwasassessedusingavailablemonitoringdata,TotalMaximumDailyLoads(TMDLs),303(d)listedimpairments,waterqualitythresholdslistedintheBasinPlanfortheCoastalWatershedsoftheLosAngelesandVenturaCounties (BasinPlan) and theCaliforniaToxicsRule (CTR). Water‐bodypollutant combinations (WBPCs)werethencategorizedusingtheTMDLs,303(d)listedimpairments,andexceedancedatafortheDominguez

Table 4.G‐1

Pollutants of Concern by Land Use

Land Use

Pollutants of Concern Su

spe

nd

ed S

olid

s

Tota

l Ph

osp

ho

rus

Tota

l Nit

roge

n

Tota

l Kje

ldah

l Nit

roge

nb

Cad

miu

m, T

ota

lb

Ch

rom

ium

, To

talb

Co

pp

er, T

ota

lb

Lead

, To

talb

Zin

c, T

ota

lb

Bio

logi

cal O

xyge

n D

em

and (

BO

D)d

Ch

em

ical O

xyge

n D

em

and (

CO

D)d

Feca

l Co

lifo

rmd

Hyd

roca

rbo

nsd

Tras

hd

Commercial X X X X c c X X X

Industrial X X X X c c X X X

Streets,

Roads

X X X X c c X X X

Educational

Facilities

X c c X X

Project Site X X X X X X X X X X X X X X

a Adapted from Table A‐3 of the Technical Manual for Stormwater Best Management Practices in the County of Los Angeles (February 2004) and the Southern California Coastal Water Research Project Land Use‐Specific Stormwater Monitoring Data. X = exceedance of “standard” by observed median/average concentration; blank = no exceedance of “standard” by observed median/average concentration.

b Derived from Table 11 of the 2012 Los Angeles County ms4 permit (page 104). c No available data to determine if these pollutants of concern originate from land use. Pollutant is assumed to be produced by this land

use unless otherwise proven by the project applicant. d Based on 2006 EPA Guide to Stormwater Pollutant Concentrations.

Source: PCR Services Corporation, Inc., 2015



ChannelEstuary.WBPCsforwhichthereweremonitoringdatawereplacedintooneofthefollowingthreecategoriesasoutlinedintheNPDESPermit:

Category1 (HighestPriority): Water body‐pollutant combinations forwhich TMDLs have beenestablished.

Category2 (HighPriority): Pollutants for which data indicate water quality impairment in thereceiving water according to the State’s Water Quality Control Policy for Developing California’sCleanWaterActSection303(d)List(StateListingPolicy).

Category3(MediumPriority): Pollutants forwhich thereare insufficientdata to indicatewaterquality impairment in thereceivingwateraccording to theState’sListingPolicy,butwhichexceedapplicablereceivingwaterlimitations.

Table4.G‐2,DominguezEstuaryWaterBodyPollutantCategorization,liststhecategorizedWBPCs.

(3) Water Supply

Basedontheinformationincludedinthemasterplan,therearethreewaterprovidersinthevicinityoftheHarbor‐UCLAMedicalCenterCampus;theMetropolitanWaterDistrict(MWD),theCaliforniaWaterServiceCompany’sRanchoDominguezDistrict(CWS),andtheCityofLosAngelesDepartmentofWaterandPower(LADWP). TheCWSownsandmaintainsdistributionmainswithintheroadwaysaroundtheCampusthatrangefromsixinchesto33inchesindiameter.CWScurrentlyprovideswatertotheProjectsitefromCWSmains at four connection points, with a backup system connection off of the LADWP main that is not

Table 4.G‐2

Dominguez Estuary Water Body Pollutant Categorizationa

Category1 Category2 Category3

DominguezEstuary(UnlinedportionbelowVermont)

Cadmium(sed.),Copper(diss.&sed.),Lead(diss.,sed.,&tissue),Zinc(diss.&sed.)DDT(tissue&sed.)PCBs(sed.)Chlordane(tissue&sed.)PAHs(sed.)BenthicCommunityEffectsSedimentToxicity

AmmoniaColiformBacteria

Arsenic(sed.)Chromium(sed.)Silver(diss.&sed.)Nickel(diss.)Mercury(sed.)Thallium(diss.)

a Adapted from Table A‐6 Water Body Pollutant Categorization. Dominguez Channel Watershed Management Area Group, 2014. Draft Coordinated Integrated Monitoring Program For The Dominguez Channel Watershed Management Area Group. http://www.waterboards.ca.gov/losangeles/water_issues/programs/stormwater/municipal/watershed_management/dominguez_channel/DominguezChannel_CIMP.pdf, accessed 12/12/15.

Source: PCR Services Corporation, Inc., 2015



continuouslyoperational. CWSusesacombinationof localgroundwaterandwaterpurchasedfromMWD,which is imported fromtheColoradoRiverand theStateWaterProject innorthernCalifornia. ReclaimedwateriscurrentlynotprovidedtotheProjectsiteandthethreeareawatersuppliersdonothavereclaimedwaterpipelinesinthearea.

(4) Hydrology

Based on information included in the Preliminary Geotechnical Evaluation for the Harbor‐UCLA MedicalCenterMasterPlan, prepared byNinyo&Moore (Appendix C), the project site is located in the Torrancecoastal plainwest of theLosAngelesRiver andnorthof the LosAngelesHarbor. Topographyof the siteslopesgentlydowntowardtheeastrangingfromanapproximateelevationof40feetabovemeansealevel(MSL)neartheeasternportionoftheprojectareatoanapproximateelevationof50feetaboveMSLinthewesternpartof theprojectarea. Off‐site flows intoand through the site areminimalasarepondingandflooding on‐site. Natural surface waters are not located on‐site. The Dominguez Channel is locatedapproximately2.7milesnorthofthesiteandrunssoutheast.

The site does not appear to have water quality or stormwater controls, such as stormwater BMPs, LIDfeatures,orhydromodificationmanagementfacilities.Stormwaterdetentionviadrywellswasimplementedfor the emergency/surgery replacement project. Rainfall and other stormwater runoff are managed byexisting roof drains, catch basins, drain inlets, underground pipes, curbs, gutters, overland sheet flows,driveways,orothermeansofconveyancetotheon‐sitestormdrains.

(5) Storm Drainage

Rainfall and other stormwater runoff are managed by existing roof drains, catch basins, drain inlets,undergroundpipes,curbs,gutters,overlandsheetflows,driveways,orothermeansofconveyancetotheon‐site stormdrains. According to theHarbor‐UCLACampusMasterPlan2,TheCountyofLosAngelesFloodControlDistrictownsandmaintainsthe208thStreetStormDrainwhichrunsthroughHarbor‐UCLAina15‐footwideeasement. This stormdrain line runs through thesite in thenorth‐southdirectionasan8‐foothighby4‐footwidereinforcedconcreteboxculvert(RCB).Near220thStreet,itturnswesterlyandflowsasan open channel in an easement towardNormandieAvenue. It joinswith the 15.7mile longDominguezChannelwhichbeginsintheCityofHawthorneandeventuallydischargestotheeastbasinoftheLosAngelesHarbor.Stainingwasnotobservedatthecatchbasins,drains,orchannelonasitevisitsbyNino&MooreonMarch4and18,2015asdiscussed in thePhase1HazardousMaterialsAssessmentHarbor‐UCLAMedicalCenter(AppendixEofthisDraftEIR).

On‐sitestormdrainsystemsflowintotheboxculvertdiscussedabove.Theon‐sitestormdrainnetworkisoperatedandmaintainedby site staff. There are currentlyminimalproblemswithpondingand flooding.ThereweredrainageissuespreviouslyinthesouthwestcornerofthecampusthatwerealleviatedbyanewconnectiontotheCountychannelandsomere‐routingoftheon‐sitedrains.Staffhasindicatedthattheon‐sitedrainagesystemisverybrittleanddifficulttoconnectto.Itislikelythatproposedprojectwouldrequireanoverhauloftheon‐sitedrainagesystem.NewconnectiontotheRCBoropenchannelownedbytheFloodControlDistrictwill requirea connectionpermit. Thispermitwill requireaproposedhydrologyanalysis

2 County of Los Angeles, 2012. Harbor‐UCLA Medical Center Campus Master Plan. http://ridley‐thomas.lacounty.gov/

PDFs/20120630_HARBOR%20UCLA%20MASTER%20PLAN.pdf,accessed12/11/15



and a comparisonwith the design peak flow rate of the existing facility. If the calculated peak flow rateexceedsthedesignpeakflowrateofthefacility,theDistrictwillgenerallyrequiredetentiontomitigatetheincreaseinpeakflowrates.

(6) Groundwater

TheCoastalPlainofLosAngelesCounty ismadeupof twogroundwaterbasins, theCentralBasinandtheWestCoastBasin.ThesebasinsarecomprisedofQuaternaryagesedimentsofgravel,sand,silt,andclaythatweredepositedfromtheerosionofnearbyhillsandmountains,andfrombeachesandshallowoceanfloorsthatcoveredtheareainthepast.UnderlyingthesesedimentsarebasementrockssuchasthePliocenePicoFormationthatgenerallydonotprovidesufficientquantitiesofgroundwater.SeparatingtheCentralBasinfromtheWestCoastBasin is theNewport‐InglewoodUplift,aseriesofdiscontinuous faultsand folds thatformaprominent lineofnorthwest trendinghills includingtheBaldwinHills,DominguezHills,andSignalHill.3 TheProject site is locatedwithin theWestCoast sub‐basinof theLosAngelesCoastalGroundwaterBasin.

TheWestCoastBasincoversapproximately140squaremilesandisboundedonthenorthbytheBaldwinHillsandtheBallonaEscarpment,ontheeastbytheNewport‐InglewoodUplift, tothesouthbySanPedroBayandthePalosVerdesHills,andtothewestbytheSantaMonicaBay.AquifersintheWestCoastBasinaregenerallyconfinedandreceivethemajorityoftheirnaturalrechargefromadjacentgroundwaterbasinsor from the Pacific Ocean (seawater intrusion). Groundwater flow in the vicinity of the site is generallytowardstheEast.4 TheProjectsiteisnotlocatednearexistingstormwaterspreadinggroundsasshowninFigure4.G‐1,StormwaterSpreadingGrounds.Assuch,stormwaterrunofffromthesitewouldnotrechargetheexistingstormwaterspreadinggroundorintroducepollutantsintothespreadingground.

(a) Depth to Groundwater

According to the Preliminary Geotechnical Evaluation for the Harbor‐UCLA Medical Center Master Plan,prepared by Ninyo & Moore (Appendix C), historic groundwater monitoring well data from the State ofCalifornia Water Resources Control Board’s GeoTracker Website5 were reviewed for wells located onadjacentproperties east andnorthof theProject site. Basedon thegroundwatermeasurements in thesewells from2007to2014,groundwater levelsat these locationshaveranged fromapproximately48 to60feet below the ground surface. The Los Angeles County Safety Element indicates that the historic highgroundwater in thevicinityof theProject site isapproximately30 feetdeep. Groundwater levelsmaybeinfluencedbyseasonalvariations,precipitation,irrigation,soil/rocktypes,groundwaterpumping,andotherfactorsandaresubjecttofluctuations.Shallowperchedconditionsmaybepresenton‐site.

3 http://www.wrd.org/engineering/introduction‐groundwater‐basins‐los‐angeles.php.Accessed12/13/15.4 Ibid.5 State of California Water Resources Control Board. http://geotracker.waterboards.ca.gov/gama/gamamap/public/

default.asp?CMD=runreport&myaddress=harbor+ucla+medical+center%2C+carson%2C+ca.Accessed,April,2015

FIGUREStormwater Spreading Grounds

Harbor-UCLA Medical Center Master Plan 4.G-1Source: Google Earth, Data: Los Angeles County Department of Public Works h p://dpw.lacounty.gov/wrd/spreadingground/SpreadingGroundMap.pdf.

P C R

0 2.50 Miles

N



Thispageintentionallyblank.



(b) Groundwater Contamination

AccordingtotheApril2015PhaseIHazardousMaterialsAssessmentHarbor‐UCLAMedicalCenterpreparedbyNino&Moore,basedonthevaryinggroundwaterflowdirectionsandproximityofseveralclosedleakingundergroundstoragetankcasesadjacenttothesite,thereisapossibilitythatgroundwaterbeneaththesiteis impacted with petroleum hydrocarbons from off‐site facilities. This is considered a recognizedenvironmentalconditionforthesite.

(c) Groundwater Recharge

According to the Preliminary Geotechnical Evaluation for the Harbor‐UCLA Medical Center Master Plan,preparedbyNinyo&Moore(AppendixC),exposedmaterialsatthesurfaceoftheProjectsiteincludeclaysand silty sandy soils. Sandy soils typically have low cohesion, and have a relatively higher potential forerosionfromsurfacerunoffwhenexposedincutslopesorutilizednearthefaceoffillembankments.Surfacesoilswithhigheramountsofclaytendtobelesserodibleastheclayactsasabindertoholdthesoilparticlestogether. Basedonthisreport,soil texturesappear tobe in theTypeCsoilgroup. Thisclassificationhastypically low saturated hydraulic conductivity rates, normally in the range of 0.04 to 0.13 inch per hour.Withthesite’simperviouscover,minimalrechargetotheWestCoastBasinoccurs.

(7) Flooding/Dam Failure/Tsunamis/Seiches

BasedonthePreliminaryGeotechnicalEvaluationfortheHarbor‐UCLAMedicalCenterMasterPlan,preparedby Ninyo & Moore (Appendix C), and maps on the California Department of Conservation website6, theprojectsiteisnotlocatedinapotentialinundationarearesultingfromadamfailure,tsunamiorseiche,norisitlocatedinalandslide/mudslidehazardzone.TheproposedProjectisnotwithina100yearfloodhazardarea. Atsunamiisaseriesofoceanwavescausedbyasuddendisplacementoftheoceanfloor,mostoftenduetoearthquakes.TheProjectsiteislocatedapproximately5.3milesinlandfromthePacificOceanand4.1milesinlandfromtheLosAngeles/LongBeachHarborarea.Aseicheisawavethatoscillatesinanenclosedwaterbody,suchasareservoir,lake,orpond.TherearenoenclosedwaterbodiesclosetotheProjectsite.TheProjectsiteisnotlocatedclosetoadam,sodamfailureisnotanissue.

b. Regulatory Setting

The following subsections discuss the various codes, regulations and polices applicable to hydrology andwaterqualityatthefederal,stateandlocallevels.

(1) Federal

(a) Clean Water Act

The Clean Water Act (CWA) is the primary federal law that protects the quality of the nation’s surfacewaters,includinglakes,rivers,andcoastalwetlands.Itisbasedontheprinciplethatalldischargesintothenation’swatersareunlawfulunlessspecificallyauthorizedbyapermit.PermitreviewistheCWA’sprimaryregulatory tool. The CWA requires states to adopt water quality standards for receivingwaters. Waterquality standards designate beneficial uses for receivingwaters (e.g., wildlife habitat, agricultural supply,fishing),andincludethecriteriarequiredtosupportthoseuses.Waterqualitycriteriaareeithernarrative6 http://www.conservation.ca.gov/cgs/maps/Pages/Maps.aspx.LandslideandTsunamiInundationMapsaccessed12/13/15.



statementsrelatedtothequalityofthewaterthatsupportaparticularuseormaximumconcentrationlevelsfor pollutants (i.e., lead, suspended sediment, bacteria, etc.). As part of the CWA, whenmonitoring dataindicate that a concentration level for a pollutant has been exceeded, the receivingwater is classified asimpairedandplacedontheCWASection303(d)ListofWaterQuality–LimitedSegmentsRequiringTMDLs(303[d] list). ATotalMaximumDailyLoad (TMDL) is thendeveloped for thepollutant(s) thatcaused theimpairment.ATMDLisanestimateofthetotalloadofpollutantsfrompoint,non‐point,andnaturalsourcesthat a water body may receive without exceeding applicable water quality standards (plus a “margin ofsafety”). ThepurposeoftheTMDListolimitthevolumeofpollutantsdischargedintothereceivingwaterfromallsources(i.e.,Stormwaterrunoff,wastewater,agriculture).

(b) National Pollutant Discharge Elimination System Construction General Permit

TheNationalPollutantDischargeEliminationSystem(NPDES)wasestablishedper1972amendmentstotheFederalWaterPollutionControlAct to controldischargesofpollutants frompoint sources7 (Section402).The1987amendments to theCWA created a sectiondevoted to Stormwaterpermitting (Section402[p]),withindividualstatesdesignatedforadministrationandenforcementoftheprovisionsoftheCWAandtheNPDES permit program. The State Water Resources Control Board (SWRCB) issues both ConstructionGeneralPermitsandIndividualPermitsunderthisprogram.

Projects thatwill disturbmore than one acre of land during construction are required to file aNotice ofIntent(NOI)withtheSWRCBtobecoveredundertheNPDESConstructionGeneralPermitfordischargesofStormwaterassociatedwithconstructionactivity. Theprojectproponentmustdevelopmeasures thatareconsistent with the Construction General Permit. Furthermore, a Stormwater Pollution Prevention Plan(SWPPP)mustbedevelopedandimplementedforeachsitecoveredundertheConstructionGeneralPermit.TheSWPPPdescribesthebestmanagementpractices(BMPs)thedischargerwillusetoprotectStormwaterrunoffandreducepotentialimpactsonsurfacewaterqualitythroughtheconstructionperiod.TheSWPPPmustcontainthefollowing:

Avisualmonitoringprogram

Achemicalmonitoringprogramfornonvisiblepollutants(tobeimplementedifaBMPfailureoccurs)

A sedimentmonitoring plan if the site discharges directly to a water body on the 303(d) list forsediment

TheareathatwouldbedisturbedundertheproposedProjectexceedsoneacre;therefore,theprojectwouldberequiredtocomplywiththeConstructionGeneralPermit.

(c) Federal Antidegradation Policy

The Federal Antidegradation Policy was released in 1968 and was included in the USEPA’s first WaterQualityStandardsRegulation.TheAntidegradationPolicyrepresentsathree‐tieredapproachtomaintainingand protecting water quality. First, all existing beneficial uses and levels of water quality necessary toprotect those uses must be preserved and protected from degradation. Second, water quality must beprotected in areas where the quality cannot support the propagation of fish, shellfish, and wildlife andrecreation (“fishable/swimmable”). Third, the policy provides special protection ofwaters forwhich the

7 Pointsourcesarediscretewaterconveyancessuchaspipesorman‐madeditches.



ordinarywaterqualitycriteriaarenotsufficient. Thesewatersarecalled“OutstandingNationalResourcesWaters”andhavebeendesignatedasuniqueorecologicallysensitive.

If anactivity isgoing tobeallowed todegradeor lowerwaterquality (insituationswhereexistingwaterquality is higher than that needed to maintain established beneficial uses), the Antidegradation Policyrequiresthatproposedprojectsmeetthecriteriabelow:

Theactivityisnecessarytoaccommodateimportanteconomicorsocialdevelopmentinthearea.

Waterqualityisadequatetoprotectandfullymaintainexistingbeneficialuses.

(d) National Flood Insurance Act

TheNationalFloodInsuranceActof1968establishedtheNationalFloodInsuranceProgram,whichisbasedontheminimalrequirementsforfloodplainmanagementandisdesignedtominimizeflooddamagewithinSpecial FloodHazardAreas. FEMA is the agency that administers theNational Flood InsuranceProgram.SpecialFloodHazardAreas(SFHA)aredefinedasareasthathaveaone‐percentchanceoffloodingwithinagivenyear,also referred toas the100‐year flood. Flood InsuranceRateMapsweredeveloped to identifyareasoffloodhazardswithinacommunity.

(2) State

(a) Porter‐Cologne Water Quality Act

California’sPorter‐CologneWaterQualityControlActof1970(Porter‐CologneAct)establishedtheSWRCBanddividedthestateintonineregionalbasins,eachwithaRegionalWaterQualityControlBoard(RWQCB).TheProjectsiteislocatedwithinthejurisdictionoftheLosAngelesRWQCB.TheSWRCBistheprimarystateagency with responsibility to protect surface water and groundwater quality. The Porter‐Cologne Actauthorizes the SWRCB to draft policies regardingwater quality in accordancewith CWA Section 303. Inaddition, thePorter‐CologneActauthorizestheSWRCBto issuewastedischargerequirements(WDRs) forprojectsthatwoulddischargetostatewaters. Theserequirementsregulatedischargesofwastetosurfaceandgroundwater, regulatewastedisposal sites, and require cleanupofdischargesof hazardousmaterialsand other pollutants. The Porter‐Cologne Act also establishes reporting requirements for unintendeddischargesofanyhazardoussubstance,sewage,oroilorpetroleumproduct.

The Porter‐Cologne Act requires the SWRCB or the RWQCBs to adoptwater quality control plans (basinplans)andpoliciesfortheprotectionofwaterquality.TheBasinPlanmustconformtothepoliciessetforthinthePorter‐CologneActandestablishedbytheSWRCBinitsStateWaterPolicy.TheBasinPlanmust:

Identifybeneficialusesforthewatertobeprotected,

Establishwaterqualityobjectivesforthereasonableprotectionofthebeneficialuses,and

Establishanimplementationprogramforachievingthewaterqualityobjectives.

Basin plans also provide the technical basis for determining WDRs, taking enforcement actions, andevaluatingcleanwatergrantproposals.Basinplansareupdatedandreviewedevery3yearsinaccordancewithArticle3ofPorter‐CologneandCWASection303(c).



(b) California Toxics Rule

TheCaliforniaToxicsRule(40CFR131.38)isaUSEPA‐issuedfederalregulationthatprovideswaterqualitycriteriaforpotentiallytoxicconstituentsinCaliforniasurfacewaterswithdesignatedusesrelatedtohumanhealthoraquaticlife.TherulefillsagapinCaliforniawaterqualitystandardsthatwascreatedin1994whenaStatecourtoverturnedtheState’swaterqualitycontrolplanscontainingwaterqualitycriteriaforprioritytoxic pollutants. These federal criteria are legally applicable in the State of California for inland surfacewaters,enclosedbays,andestuaries forallpurposesandprogramsundertheCWA. TheCaliforniaToxicsRuleestablishestwotypesofaquaticlifecriteria:

Acutecriteriarepresentthehighestconcentrationofapollutanttowhichaquaticlifecanbeexposedforashortperiodoftime8withoutharmfuleffects,and

Chroniccriteriaequalthehighestconcentrationtowhichaquaticlifecanbeexposedforanextendedperiodoftime(fourdays)withoutdeleteriouseffects.

Duetotheintermittentnatureofstormwaterrunoff(especiallyinsouthernCalifornia),theacutecriteriaareconsideredtobemoreapplicabletostormwaterconditionsthanchroniccriteria.

(c) State Antidegradation Policy

Under the State’s Antidegradation Policy (as set forth in SWRCB Resolution No. 68‐16), whenever theexistingqualityofwaters isbetterthanwhat isneededtoprotectpresentandfuturebeneficialuses,suchexistingqualitymustbemaintained.ThisStatepolicyhasbeenadoptedasawaterqualityobjectiveinalltheState’s Basin Plans. The State policy establishes a two‐step process to determine if discharges with thepotentialtodegradethewaterqualityofsurfaceorgroundwaterwillbeallowed.

The first step requires that, where a discharge would degrade high‐quality water, the discharge may beallowedonlyifanychangeinwaterqualitywould:

BeconsistentwiththemaximumbenefittothepeopleoftheState;

Notreasonablyaffectpresentandanticipatedbeneficialusesofsuchwater;

Result in water quality that is not less than that which is prescribed in State policies (i.e., BasinPlans).

Thesecondstep(assetforthinSWRCBResolutionNo.68‐16)statesthatanyactivityresultingindischargetohigh‐qualitywatersisrequiredtousethebestpracticabletreatmentorcontrolofthedischargenecessaryin order to avoid the occurrence of pollution or nuisance and to maintain the “highest water qualityconsistentwiththemaximumbenefittothepeopleofthestate”.TheStatepolicyappliestobothsurfaceandgroundwater,aswellastobothexistingandpotentialbeneficialusesoftheapplicablewaters.

In1999,theSWRCBissuedandsubsequentlyamendedtheGeneralConstructionStormWaterPermit(WaterQualityOrder99‐08‐DWQ),whichgovernsdischargesfromconstructionsitesthatdisturboneacreormoreofsurfacearea. Again,onSeptember2,2009,theSWRCBadoptedanewGeneralConstructionPermitthatsubstantially alters the approach taken to regulate construction discharges through (1) requiring the

8 Theruledoesnotspecifytimeframefor“acute”.Standardpracticewouldlikelyimplythatanyconditionthatispermanentorsemi‐

permanentischronic;allelsewouldbeshort‐term.



determination of risk levels posed by a project’s construction discharges to water quality and (2)establishingnumericalwaterqualitythresholdsthattriggerpermitviolations.ThesenewpermitregulationstookeffectonJuly1,2010.

(3) Local

(a) Water Quality Control Plan, Los Angeles Region

AsrequiredbytheCaliforniaWaterCode,theLARWQCBhasadoptedthe“WaterQualityControlPlan,LosAngelesRegion:BasinPlanfortheCoastalWatershedsofLosAngelesandVenturaCounties”(LABasinPlan).Specifically,theLABasinPlandesignatesbeneficialusesforsurfacewaterandgroundwater,setsnarrativeandnumericalobjectivesthatmustbeattainedormaintainedtoprotectthedesignatedbeneficialusesandconformtotheState'sAntidegradationppolicy,anddescribesimplementationprogramstoprotectallwatersintheLosAngelesregion.Inaddition,theLABasinPlanincorporates(byreference)allapplicableStateandRegionalBoardplansandpoliciesandotherpertinentwaterqualitypoliciesandregulations.ThoseofotheragenciesarereferencedinappropriatesectionsthroughouttheLABasinPlan.9

(b) Municipal Storm Water Permitting

As part of its NPDES Program, the Los Angeles RWQCB adopted a newMunicipal Separate Storm SewerPermit(MS4Permit,sometimesreferredtoasaStormwaterPermit)in2012. MS4Permitswereissuedintwophases.PhaseIwasinitiatedin1990,underwhichtheRWQCBsadoptedNPDESstormwaterpermitsformedium(between100,000and250,000people)and large(morethan250,000people)municipalities. Aspart of Phase II, the SWRCB adopted a General Permit for small MS4s (than 100,000 people) and non‐traditionalsmallMS4sincludinggovernmentalfacilitiessuchasmilitarybases,publiccampuses,andprisonandhospitalcomplexes(WQOrderNo.2003‐0005‐DWQ).

TheLosAngelesRWQCB’s2012MS4Permitnamed84incorporatedcities,theCounty,andtheLosAngelesCountyFloodControlDistrict aspermittees.TheMS4Permit imposesanumberofbasicprograms, calledMinimumControlMeasures,onallpermittees inorder tomaintaina levelof acceptable runoff conditionsthrough the implementation of practices, devices, or designs generally referred to as BMPs, thatmitigatestormwater quality problems. As an example, the development construction program requires theimplementation of temporary BMPs during a project’s construction phase to protect water resources bypreventingerosion,controllingrunoff,protectingnaturalslopesandchannels,storingfluidssafely,managingspillsquickly,andconservingnaturalareas.

(c) Los Angeles County Low‐Impact Development Ordinance

In December 2012, the Los Angeles County Board of Supervisors updated the County Low ImpactDevelopment (LID) Ordinance (Chapter 12.84 of the County Code [LACC]) for compliancewith the 2012LARWQCBMS4Permit.TheupdatedLIDOrdinancerequirestheintegrationintoprojectdesignanarrayoffeasible design features and operational practices for the retention, detention, storage, and filtration ofstormwater andurban runoff, prior to discharge off‐site. LID generally relies on an integrated systemof

9 California RegionalWater Quality Control Board,Water Quality Control Plan: Los Angeles Region Basin Plan for the Coastal

Watersheds of Los Angeles and Ventura Counties, adopted June 13, 1994 http://www.waterboards.ca.gov/losangeles/water_issues/programs/basin_plan/.AccessedJune16,2015.



decentralized, small‐scale control measures that can be implemented at a project site, using structuraldevices, engineered systems, vegetated natural designs, and other techniques to control stormwater andurbanrunoffon‐siteandnotsolelythroughoff‐siteconveyanceoratanoff‐sitecollectionpoint.

(d) Los Angeles County General Plan Update (2035)

TheCaliforniaGovernmentCodeSection65300requiresgeneralplansto include“aconservationelement,which includes evaluation of water resources for supply and demand. As such, the Los Angeles CountyGeneralPlanUpdate(2035)ConservationandNaturalResourceElement(Chapter9,SectionIV,LocalWaterResources) addresses water management as an invaluable resource and effective management andpreservation of local water resources are vital to preserving a high quality of life for residents andbusinesses,aswellasforsustainingthefunctioningofwatershedsandthenaturalenvironment.ApplicablegoalsandpolicesfromtheSafetyElementareidentifiedbelow:

GoalC/NR5:Protectedanduseablelocalsurfacewaterresources.

PolicyC/NR5.1:SupporttheLowImpactDevelopment(LID)philosophy,whichseekstoplan and design public and private development with hydrologic sensitivity, includinglimitstostraighteningandchannelizingnaturalflowpaths,removalofvegetativecover,compactionofsoils,anddistributionofnaturalisticBMPsatregional,neighborhood,andparcel‐levelscales.

Policy C/NR 5.3: Actively engage with stakeholders in the formulation andimplementationof surfacewaterpreservationand restorationplans, includingplans toimprove impaired surface water bodies by retrofitting tributary watersheds with LIDtypesofBMPs.

PolicyC/NR5.4: Support the retrofitting of unreinforcedmasonry structures to helpreducetheriskofstructuralandhumanlossduetoseismichazards.

GoalC/NR6:Protectedandusablelocalgroundwaterresources.

Policy C/NR 6.1: Support the LID philosophy, which incorporates distributed, post‐constructionparcel‐levelstormwaterinfiltrationaspartofnewdevelopment.

PolicyC/NR6.2: Protect natural groundwater recharge areas and regional spreadinggrounds.

Policy C/NR 6.3: Actively engage in stakeholder efforts to disperse rainwater andstormwater infiltrationBMPsatregional,neighborhood, infrastructure,andparcel‐levelscales.

PolicyC/NR6.5:Preventstormwaterinfiltrationwhereinappropriateandunsafe,suchas in areas with high seasonal groundwater, on hazardous slopes, within 100 feet ofdrinkingwaterwells,andincontaminatedsoils.

GoalC/NR7:Protectedandusablelocalgroundwaterresources.



PolicyC/NR7.1:SupporttheLIDphilosophy,whichmimicsthenaturalhydrologiccycleusing undeveloped conditions as a base, in public and private land use planning anddevelopmentdesign.

PolicyC/NR7.3:ActivelyengagewithstakeholderstoincorporatetheLIDphilosophyinthe preparation and implementation of watershed and river master plans, ecosystemrestorationprojects,andotherrelatednaturalresourceconservationaims,andsupportthe implementationofexistingefforts, includingWatershedManagementProgramsandEnhancedWatershedManagementPrograms.

3. ENVIRONMENTAL IMPACTS

a. Methodology

(1) Surface Hydrology and Drainage

Theanalysisofhydrology impacts isbasedonpostprojectrunoffratesduringstormeventscalculatedfortheHarbor‐UCLAMasterPlan.Potentialimpactstothestormdrainsystemwereanalyzedbycomparingthecalculatedpre‐projectrunoffratestothecalculatedpost‐projectrunoffrates, takingintoconsiderationthecapacityoftheexistingstormdrainsystemsservingthesite.

(2) Water Quality

Waterqualityimpactswereassessedbyconsideringthetypesofpollutantsand/oreffectsonwaterqualitylikely to be associated with construction and operation of the project, project design features to treatcontaminants, and expected contaminant flows with project implementation. Project consistency withrelevantregulatorypermits/requirements,includingBMPsandapplicableplans,isevaluatedtodemonstratehowcompliancewouldensurethattheprojectwouldnotsignificantlydegradeexistingwaterquality.

(3) Flooding

FloodingimpactswereaddressedinconsiderationofapplicablesafetypoliciesoftheCounty’sGeneralPlanSafetyElementandthedesignrequirementswithintheCounty’sMunicipalCode.Adeterminationwasmadeas towhether suchpolicies,procedures, and regulatory requirementswouldadequatelyaddresspotentialfloodinghazardsonthesite.

(4) Groundwater

Groundwaterimpactswereevaluatedbyestimatingthedomesticwaterdemandsoftheproposedproject,aportionofwhichisprovidedbylocalgroundwaterbasins,relativetothesafeyieldofaffectedaquifers.

b. Thresholds of Significance

The potential for hydrology andwater quality impacts is based on thresholds derived from the County’sInitialStudyChecklistquestions,whichareinpartbasedonAppendixGoftheStateCEQAGuidelines.Thesequestionsareasfollows:



(IX) Hydrology and Water Quality. Would the project:

a) Violateanywaterqualitystandardsorwastedischargerequirements?

b) Substantially deplete groundwater supplies or interfere substantially with groundwater rechargesuchthattherewouldbeanetdeficitinaquifervolumeoraloweringofthelocalgroundwatertablelevel (e.g., theproductionrateofpreexistingnearbywellswoulddrop toa levelwhichwouldnotsupportexistinglandusesorplannedusesforwhichpermitshavebeengranted)?

c) Substantiallyaltertheexistingdrainagepatternofthesiteorarea,includingthroughthealterationofthecourseofastreamorriver,inamannerwhichwouldresultinsubstantialerosionorsiltationonoroffsite?

d) Substantiallyaltertheexistingdrainagepatternofthesiteorarea,includingthroughthealternationofthecourseofastreamorriver,orsubstantiallyincreasetherateoramountofsurfacerunoffinamannerwhichwouldresultinfloodingon‐oroff‐site?

e) Create or contribute runoff water which would exceed the capacity of existing or plannedstormwaterdrainagesystemsorprovidesubstantialadditionalsourcesofpollutedrunoff?

f) Otherwisesubstantiallydegradewaterquality?

g) Placehousingwithina100‐yearfloodhazardareaasmappedonafederalFloodHazardBoundaryorFloodInsuranceRateMaporotherfloodhazarddelineationmap?

h) Placewithina100yearfloodhazardareastructureswhichwouldimpedeorredirectfloodflows?

i) Exposepeopleorstructurestoasignificantriskofloss,injuryordeathinvolvingflooding,includingfloodingasaresultofthefailureofaleveeordam?

j) Inundationbyseiche,tsunami,ormudflow?

The Initial Study determined that the Project would have less than significant impacts with respect toChecklistquestionsIX.g),h),i),andj.Accordingly,theseenvironmentaltopicsarenotevaluatedinthisEIR.

Basedontheabovefactors,theProjectwouldhaveapotentiallysignificantimpactonHydrologyandWaterQualityifitwould:

HWQ‐1: Violateanywaterqualitystandardsorwastedischargerequirements.

HWQ‐2: Substantially deplete groundwater supplies or interfere substantially with groundwaterrechargesuchthattherewouldbeanetdeficit inaquifervolumeora loweringof the localgroundwatertablelevel(e.g.,theproductionrateofpre‐existingnearbywellswoulddropto



a levelwhichwouldnotsupportexistinglandusesorplannedusesforwhichpermitshavebeengranted)

HWQ‐3: Substantially alter the existing drainage pattern of the site or area, including throughalterationof thecourseofastreamorriver, inamannerwhichwouldresult insubstantialerosionorsiltationon‐oroff‐site.

HWQ‐4: Substantially alter the existing drainage pattern of the site or area, including through thealterationofthecourseofastreamorriver,orsubstantially increasetherateoramountofsurfacerunoffinamannerthatwouldresultinfloodingon‐oroff‐site.

HWQ‐5: Create or contribute runoffwaterwhichwould exceed the capacity of existing or plannedstormwaterdrainagesystemsorprovidesubstantialadditionalsourcesofpollutedrunoff.

HWQ‐6: Otherwisesubstantiallydegradewaterquality.

c. Project Characteristics or Design Features

TheProjectwouldcomplywithallapplicablerequirementsandpermitsrelatedtostormwatermanagementandwaterquality.Aspartofthis,constructionplansforindividualcomponentsoftheHarbor‐UCLAMedicalCenterMasterPlanProjectwouldbereviewedbytheCountytoconfirmimplementationoftheappropriatetemporary construction and permanent operational BMPs for compliancewith the SWRCB’s ConstructionGeneralPermit,theCounty‐administeredMS4permit,andtheCounty’sLIDordinance.

d. Project Impacts

Threshold HWQ‐1: Would the Project violate any water quality standards or waste dischargerequirements?

ImpactStatementHWQ‐1:With compliance with regulatory requirements governing stormwatermanagement andwater quality during construction and following buildout ofmaster Plan Projectcomponents, impacts onwater quality or related towaste discharge (i.e., construction dewatering)wouldbelessthansignificant.

(1) Construction

Constructionactivitieswouldincludetheuseofheavyequipmentandconstruction‐relatedchemicals,suchasfuels,oils,grease,solvents,andpaintsthatwouldbestoredinlimitedquantitieson‐site.Intheabsenceofproper controls, these construction activities could result in accidental spills or disposal of potentiallyharmfulmaterials that couldwash into and pollute surfacewaters or groundwater. During construction,portionsoftheHarbor‐UCLACampuswouldbesubjecttoground‐disturbingactivities(e.g.,removaloftheexistingstructuresandpavement,excavationandgrading, foundationandinfrastructureconstruction,andthe installation of utilities). These activities would expose soils for a limited time, allowing for possibleerosion and sediments to enter into sheet flow runoff,which couldenter the existing stormdrain systemuntreated.Therefore,surfacewaterqualitycouldbetemporarilyaffectedbyconstructionactivities.



However,theProjectwouldbesubjecttoexistingregulationsgoverningwaterquality.ConstructionGeneralPermitswould be required from the SWRCB for individual Project components of the. The ConstructionGeneralPermitandassociatedNPDESrequirements includedevelopmentandimplementationofaSWPPPwithappropriateNMPs,aswellasassociatedmonitoringandreporting.StormwaterBMPsareintendedtolimit erosion, minimize sedimentation, and control stormwater runoff water quality during constructionactivities.BMPscouldinclude,butarenotlimitedto,theuseoforimplementationofwaterbars,siltfences,staked straw bales, and avoidance of water bodies during construction. Additional source‐control BMPsmight also be required to prevent runoff contamination bypotentially hazardousmaterials and eliminatenon‐stormwaterdischarges.

Compliance with the Construction General Permit, SWPPP, and NPDES requirements that requireconstruction phase BMPs are considered protective of water quality during construction and would,therefore, prevent a substantial violation of water quality standards and minimize the potential forcontributing additional sources of polluted runoff during construction of the project. These existingregulations,programs,andpolicieswouldensurethatwater‐andwind‐relatederosionwouldbeconfinedtothe construction area andnot transportedoff‐site, and therefore ensure construction activitieswouldnotdegradethesurfacewaterqualityofreceivingwaterstolevelsbelowstandardsconsideredacceptablebytheLos Angeles RWQCB and/or other regulatory agencies or affect the beneficial uses of receiving waters.Compliance with regulatory requirements would ensure that construction of Master Plan Projectcomponentswouldnot result in the exceedanceofwaterquality standardsduring construction, includingTMDL limits applicable to theDominguezChannel. In addition, the topographic gradientson theHarbor‐UCLACampusarerelativelygentle.

ThepotentialforanyspillorreleaseofconstructionrelatedchemicalsduringProjectconstructionwouldbegenerally small because of the localized, short‐term nature of the releases. Furthermore, the NPDESConstruction General Permit and SWPPP require measures regarding the handling of these types ofmaterials and action protocols if a spill or release does occur. Therefore, potential soil erosion andsedimentationimpactsduringconstructionwouldbelessthansignificantandnomitigationisrequired.

AccordingtothePreliminaryGeotechnicalReportpreparedfortheProject(AppendixC),groundwaterlevelshave ranged from approximately 48 to 60 feet below ground surface (bgs). Based on the depths togroundwaterwithin theproject site, constructiondewatering isnot anticipated tobe required. However,shouldgroundwaterbeencounteredthatwouldrequiredewatering,theCountywouldrequirecontractorsfor individual Project components to apply for coverage and adhere to the monitoring and reportingprogramunderRWQCBOrderNo.R8‐2009‐0003. Compliancewith these regulatory requirementswouldensure that dewatering activities would not result in the exceedance of water quality standards duringconstruction, includingTMDL limits applicable toDominguezChannel. Basedon the above, construction‐relateddewateringimpactswouldbelessthansignificant.

(2) Operations

Stormwaterdischargeisgeneratedbyrainfallthatrunsoffthelandandimpervioussurfacessuchaspavedstreets,parkinglots,androoftops.Stormwaterdischargemayincludepollutantsofconcern,whicharethosethatareexpectedtobegeneratedbytheprojectandthatcouldimpactstormwater.DuringoperationoftheProject,pollutantsofconcernwithinrunoffmayinclude,butarenotlimitedto,pollutantssuchassediment,hydrocarbons,oil,grease,heavymetals,nutrients,herbicides,pesticides, fecalcoliformbacteria,andtrash.



Thisrunoffcanflowdirectlyintostormdrainsandcontinuethroughpipesuntilitisreleased,untreated,intothe Dominguez Channel. Untreated stormwater runoff degrades water quality in surface waters andgroundwaterandcanaffectdrinkingwater,humanhealth,andplantandanimalhabitats.

Reducing natural resource demands is a key goal of the Master Plan Project. By utilizing landscape instrategic ways it can perform a variety of tasks beyond aesthetics including lowering potable waterdemands,reducingheatislandeffects,andmitigatingbuildingcoolingdemands.Landscapeplanscallfortheuse of native or culturally native (adaptive) low‐maintenance species, which would be maintained byworkerswhoaretrainedtoworkwithnativeCalifornialandscapes.Inaddition,theProjectwouldrelyonitslandscapetoreducedependencyonnaturalresourcesbyreducingwaterdemands,capturingandcleaningstormwaterrunoff,andshadingbuildingstohelpreducecoolingdemands.TheProjectwouldconvertmorethan threeacresof existing turf area to lowwateruseplants, saving an estimate sevenmilliongallonsofwaterperyearovercurrentusage.TheProjectwouldintroducenewtreesinsurfaceparkingareastocreatea dense canopy of shade which will reduce the asphalt’s solar absorption rate, allowing surroundingbuildingstocooldownearlierintheevening,reducingtheurbanheatislandeffect.Furthermore,theProjectproposestoincorporategreenroofs,whichwillhelpreducebuildings’solarabsorptionandcoolingdemandsduringwarmerdaytimehours.TheProjectwouldavoidtheuseofpollutants,chemicals,orsoilamendmentsthat could harm the human or ecological health. Organic maintenance methods or Integrated PestManagementmaybeused.

AnyproposednewstormdrainconnectionstotheRCBoropenchannelownedbytheFloodControlDistrictwill require a connection permit. This permit will in turn require a proposed hydrology analysis and acomparison with the design peak flow rate of the facility. If the calculated peak flow rate exceeds thefacility’sdesignpeakflowrate,theDistrictwillgenerallyrequiredetentiontomitigatetheincreaseinpeakflowrates.

Asdiscussed,theHarbor‐UCLACampusiscurrentlyfullydevelopedandwouldberequiredtocaptureandinfiltrateorreusethedifferenceinvolumeduringthe0.75‐inchstormeventbetweenadevelopedsiteandthe site in an undeveloped condition (0 percent impervious,)where feasible based on the LID Standards.TheCountyalsorequiresthatthe0.75‐inchrainfalleventbetreatedtoremoveurbanstormwaterpollution.Based on information provided in the Harbor‐UCLA Master Plan, the required treatment flow rate isapproximately 0.17 cubic feet per second (cfs) per acre based on a flow rate design and the requiredtreatmentvolumeisapproximately2,200cubicfeetperacrebasedonavolumedesign.Theexcessvolumetobeinfiltrated,reused,orstoredisapproximately1,940cubicfeetperacre.Previouslyapprovedgradingplans fortheemergency/surgeryreplacementbuilding indicatethatseveraldrywellswereconstructed intheareaofnewconstructiontomeetthisrequirement;thisapproachislikelytobeimplementedforfutureareastoberedevelopedontheCampus.10

Additionally, the incorporation of LID requirements is a significant element of the proposed sitesustainability approach andLID featureswouldmeet the requirements found in theCounty’sLow‐ImpactDevelopment Standards Manual. The LID features would provide treatment control through physical,biological, and chemical processes to remove pollutants from stormwater runoff. Potential LID features

10 CampusMaster PlanAddendum, CountyOf LosAngelesHarbor‐UCLAMedical Center, Phase 04‐F, Civil – Facilities andUtilities

Assessment,pageF‐10.



include: bioretention/rain gardens, strategic grading, resource conservation, flatter wider swales, flatterslopes, long flow paths, tree/shrub depression, turf depression, landscape island storage, rooftopdetention/retention, roof leader disconnection, parking lot/street storage, smaller culverts/pipes/inlets,amended soils, alternative materials, tree box filters, alternative impervious surfaces, reduce impervioussurface, rain barrels/cisterns/water use, catch basins/seepage pits, sidewalk storage, vegetativeswales/buffers and strips, infiltration swales and trenches, eliminate curb and gutter, drywell,maximizesheetflow,maintaindrainagepatterns,greenroofs,andpermeablepavement.Anillustrationofthetypeandlocationof theProject’sproposedBMPs isprovided inFigure4.G‐2,PotentialLIDStrategies. TheProjectwillalsoincreasetheamountofperviousareaontheHarbor‐UCLACampus,whichwillreducethecalculatedpeakflowofstormwaterrunoff.

Provided that LID features (especially the design of any bioretention features) include modifications toaddress thepotential leachingof nutrients, compliancewithCountyLID criteria andother state and localregulationsthatrequirepost‐constructionBMPswouldensurethatoperationsontheHarbor‐UCLACampuswould not degrade the surface water quality of receiving waters to levels below standards consideredacceptable by the Los Angles RWQCB or other regulatory agencies or impair the beneficial uses of thereceivingwaters.

FollowingbuildoutofProjectcomponents,materialssuchasfuelsorsolventsmaybestoredon‐site,similartoexistingconditions. Thisisnotanticipatedtobeasourceofpollutedstormwaterrunoffordry‐weatherrunoff.Asunderexistingconditions,Harbor‐UCLAwouldcontinuetoadheretoallapplicableregulations.

Accordingly, operationswouldnot result in a violationof anywaterquality standardsorwastedischargerequirements, would not create substantial additional sources of polluted runoff, and would notsubstantiallydegradewaterquality,andwouldthereforebelessthansignificant.

ThresholdHWQ‐2:WouldtheProjectsubstantiallydepletegroundwatersuppliesorinterferesubstantiallywithgroundwaterrecharge?

ImpactStatementHWQ‐2: Project‐related excavation is not expected to extend to the depth ofgroundwaterbeneath theHarbor‐UCLACampus,withonly temporarydewateringanticipated in theevent seepage is encountered at shallower depths than anticipated. Project implementation wouldincrease pervious area on the Campus over existing conditions through the introduction of morelandscapedareaanddoesnotproposewithdrawalofgroundwatertomeetwaterdemand.TheProject’sindirect employment‐related population growth would not substantially increase demand ongroundwatersuppliesservingtheProjectSite,thus impactsregardinggroundwatersupplieswouldbelessthansignificant.

(1) Construction

Construction activities are not expected to require excavation below the normal or seasonally highgroundwaterlevels.However,ifseepageisencounteredduringconstruction,dewateringmaybenecessary.Anyseepageencounteredduringconstructionwouldbemitigated,asneeded,byconstructingsmalldrainageswalesfromthebaseoftheexcavationstotemporarysumppitsorexistingLIDfeatureson‐site.

FIGUREStormwater Spreading Grounds

Harbor-UCLA Medical Center Master Plan 4.G-2Source: County of Los Angeles, Harbor-UCLA Medical Center Campus Master Plan, June 2012.

P C R

FUTURE BIOSCIENCEDEVELOPMENT AREA

FUTUREBIOSCIENCE

DEV’T

BIOSCIENCEPARKING

FUTURE BIOSCIENCE

DEV’T

FUTURE BIOSCIENCEDEVELOPMENT AREA



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Any discharge of groundwater during constructionwould be implemented in compliancewith applicableNPDES permit requirements. The Project would also comply with all applicable federal, state, and localrequirementsconcerningthehandling,storage,anddisposalofhazardousmaterialstoreducethepotentialforareleaseofcontaminants into thegroundwaterasaresultofprojectconstruction. Thus,constructionactivitieswouldnotdegradegroundwaterqualityorinterferewithrechargeandimpactswouldbelessthansignificant.

(2) Operation

Under theMaster Plan Project, water demand is projected to increase as the result of intensified use offacilitiesandagreateramountof landscapingon theCampus. Waterusage is likely to increase followingProjectbuildoutbecauseoftheincreasednumberofemployeesand,potentially,patientsusingHarbor‐UCLAMedicalCenter facilities.However, increased regionalwaterdemand isprimarily a functionofpopulationgrowth, and as the Projectwould not directly or indirectly result in substantial population growth in thearea, it would not significantly increase demand for water supplies, including groundwater serving theProject area. Additionally, indoor fixtures would comply with applicable Municipal Codes requirementsrelatedtoreducingindoorwaterconsumptionthroughmaximumflowratesforindoorwaterfixtures.Theserequirements would limit potential increases in indoor water usage on the Campus. See Section 4.M.1,WaterSupply,ofthisDraftEIRforfurtherdiscussionofProject‐relatedwaterdemandandsupply.

Aspreviouslystated,Harbor‐UCLAreceivesitswatersuppliesfromCWS,whichdrawsonacombinationoflocalgroundwater(i.e.,theCentralBasin)andwaterpurchasedfromMWD.AtProjectbuildout,theamountofperviousareaontheCampuswillbe increased,whichmayincrementally increaserechargeof theWestBasinthroughinfiltrationbasedontheLIDfeaturesimplementedtoreduceoff‐sitedischargeofstormwateranddryweatherrunoff.However,theincreaseinlandscapedareaontheCampusisexpectedtoincreasetheneedforirrigationoverexistingconditions.Currentlawnareaswillbereducedandplantedwithdrought‐tolerant plants reducing water usage. The proposed plant palette would include drought‐tolerant andCalifornianativeplantsincompliancewiththeCounty’slandscapeordinance,andthereforetheuseofplantspecieswithhightomoderatewaterneedswouldbelimited.

Reclaimedwater is currentlynotprovided to theProjectSiteand the irrigation system is suppliedby theCWSmunicipaldomesticwatersystem.Futureopportunitiesforpotentialwatersourcesforirrigationuseinclude continuingwith themunicipalwater supply, a futuremunicipal recycledwater supply, an on‐siteintegrated stormwater management system, and/or an on‐site recycled water system. Any of proposedrecycledwatersystemsortheon‐siteintegratedstormwatermanagementsystemwouldreducetheuseofpotablewater.

TheMasterPlanProjectwouldnotinvolveanygroundwaterextractionorotheractivitiesthatcouldresultindirectwithdrawalordepletionofgroundwatersupplies. Asnotedabove,aportionoftheMedicalCenter’swater supply is provided by groundwater from local aquifers, and as such the implementation of theproposed Project would indirectly increase demands on the groundwater basins. However, the Projectwouldnot result in any adverse impacts to the localwater supplies, including groundwater resources, asalthoughtheproposeddevelopmentwasnotspecificallyaccountedforinthemostrecentlyadoptedUrbanWaterManagementPlan(UWMP)fortheMedicalCenterCampusservicearea,theWaterSupplyAssessmentpreparedfortheMasterPlanProject(includedinAppendixIofthisDraftEIR)demonstratesthatadequatewater supplies are available to meet projected demands. As the Project would not directly affect



groundwater resources, and indirect demands on local groundwater supplieswould not exceed availablesupplies,impactsongroundwaterresourceswouldbelessthansignificant.

ThresholdHWQ‐3: WouldtheProjectsubstantiallyaltertheexistingdrainagepatternofthesiteorarea,including through the alteration of the course of a stream or river, in a manner that would result insubstantialerosionorsiltationon‐oroff‐site?

ImpactStatementHWQ‐3: The Project would redevelop the already fully developed Harbor‐UCLACampus, and, with compliance with NPDES regulations and County LID requirements governingconstruction and post‐project stormwatermanagement andwater quality, would not substantiallyalterexistingdrainagepatternsinamannerthatwouldresultinsubstantialerosionorsiltation.

(1) Construction

Gradingandexcavationwouldberequiredforbuildingfoundations,whichcouldaffectdrainageonthesitesofspecificMasterPlanProjectcomponents.However,asthesiteiscurrentlyfullydeveloped,theproposedProjectwouldnotsubstantiallyaltertheexistingdrainagepatternofthesiteorresultinsubstantialerosionorsiltation. StandardconstructionphaseBMPsrequired forcompliancewithNPDESrequirementswoulddecrease the potential for any significant erosion or sedimentation from soil disturbance associatedwithconstruction.TherearenostreamsorriversnearbywhosecoursewouldbealteredbytheproposedProject.

Anypotentialimpactsonwaterqualityarisingfromerosionandsedimentationareexpectedtobelocalizedand temporary (i.e. during construction). NPDES compliance would require contractors to implementmeasurestominimizeandcontainerosionandsedimentationandberequiredtosubmitagradingplantothe County for approval prior to the commencement of any construction activities. In addition, whereproposedconstructionforaspecificMasterPlanProjectcomponentwoulddisturbmorethanoneacre,theprojectproponentwouldbe required toobtainand complywith theNPDESConstructionGeneralPermit.ThepermitwouldrequireaSWPPPandcompliancewithCountyrequirementstomeetstatewaterqualityobjectives. Pending possible revisions as of thiswriting, theNPDESpermitting processmay also requiredevelopment of a rain‐event action plan prior to permit approval. Construction‐related erosion andsedimentationimpactsresultingfromsoildisturbancewouldbelessthansignificantafterimplementationoftheSWPPP(seeMM‐HWQ‐1)andtheBMPsrequiredtocontrolerosionandsedimentation.

(2) Operation

Aspreviouslystated,theamountoflandscapedareawouldincreasefollowingProjectbuildoutoverexistingconditions. Moreover, for each Project component, Harbor‐UCLA would be required to identify andimplement appropriate LID compliance features and practices include structural BMPS such as filtration,runoff‐minimizinglandscapingforcommonareas,andenergydissipaters,whichwouldreducepeakrunoffvolumesaswellastheoverallamountofrunoffdischargedcomparedtoexistingconditions.Therefore,overtime, Project implementation is expected to improve stormwatermanagement conditions on theHarbor‐UCLACampusandreducethepotentialforerosionandsedimentation.



ThresholdHWQ‐4: WouldtheProjectsubstantiallyaltertheexistingdrainagepatternofthesiteorarea,including through the alteration of the course of a stream or river, or substantially increase the rate oramountofsurfacerunoffinamannerthatwouldresultinfloodingon‐oroff‐site?

ImpactStatementHWQ‐4: The Project would redevelop the already fully developed Harbor‐UCLACampusandwouldnot substantiallyalterexisting topographyoraffect thecourseofany streamsorrivers.Neitherconstructionnoroperationswouldincreasesurfacerunoffinamannerthatwouldresultin flooding. Therefore, impacts on existing drainage patterns of the Project sitewould be less thansignificant.

(1) Construction

The Harbor‐UCLA Campus is already developed and proposed grading and excavation would notsubstantiallyalteritsoveralltopography.Waterusedduringconstruction(e.g.fordustcompression)wouldbemechanicallyandpreciselyappliedandwould infiltrateorevaporate. Project‐relatedexcavation isnotexpected to intercept groundwater, and in the event of possible seepage within excavations, temporarydewateringwouldbeconductedinaccordancewithNPDESrequirementsgoverningsuchdischarges.

(2) Operation

As previously stated, Project buildoutwould not substantially alter the existing drainage patterns on theHarbor‐UCLACampus,Projectarea,orreceivingwaters,orresult insubstantialerosionorsiltationon‐oroff‐site. FutureProject hydrologic boundaries andoff‐site stormdrain infrastructure serving theCampuswill closelymatchexistingconditions. With the increase inperviousarea, thecalculatedpeak flowof thefuture development will generally be less than under existing conditions; in addition, any future sitedevelopment will require compliance with County of Los Angeles and LID standards for stormwatermanagement.Assuch,theprojectwouldnotresultinasubstantialincreaseintherateoramountofsurfacerunofforresultinfloodingon‐or‐off‐site.Impactswouldbelessthansignificant.

ThresholdHWQ‐5:WouldtheProjectcreateorcontributerunoffwaterthatwouldexceedthecapacityofexisting or planned stormwater drainage systems or provide substantial additional sources of pollutedrunoff?

ImpactStatementHWQ‐5:WithadherencetoCountyconnectionpermitrequirementsandcompliancewithCountyLIDrequirements,thevolumesofrunoffdischargedtotheCounty’sstormdrainsystemfollowingProjectbuildoutwouldbe similarorreducedcompared toexistingconditionsandwouldnotprovideadditionalsourcesofpollutedrunoff;impactswouldbelessthansignificant.

(1) Construction and Operation

Aspreviouslystated, futureCampushydrologicboundariesandoff‐sitestormdrain infrastructureservingtheCampuswillcloselymatchexistingconditions.ThebackboneofthedrainsystemwillcontinuetobetheCounty‐ownedandoperated208thStreetStormDrain,an8‐footby4‐footRCBculvertwhichrunsbeneaththeMedicalCenter inanorth‐south15‐footwideeasement,daylighting intoanopenculvert thatparallels220thStreetanddischargestotheundergroundnetworkatNormandieAvenuetothewest.Sincethedesignof future Project facilities is presently conceptual, it is unknown whether new connections to the 228th



StreetStormDrainmayberequiredaspartoftheProject,butitisconsideredlikelyduetotheageandbrittleconditionofthesystem. However,futureconnectionswouldrequireaconnectionpermitfromtheCountyFloodControlDistrict,whichwillinturnrequireahydrologyanalysisandcomparisonwiththedesignpeakflow rate of the facility. As previously discussed, the County will require stormwater detention if thecalculated peak flow rate exceeds the facility’s design peak flow rate. Stormwater managementinfrastructure constructed for individual Project components would be constructed in compliance withpermitandLIDrequirementsandincludeupgradedinfrastructuresizedforfuturestormwatervolumes.

TheCountyofLosAngelesdetermines theallowable amountof runoff that canenter its systembasedonhistoricalrecords. It is likelythattheflowrateallowedatconnectionstotheCountyStormDrainswillberequired to match the original system design flow rate. As previously stated, new development in LosAngelesCountyisrequiredtocaptureandinfiltrateorreusethedifferenceinvolumeduringthe0.75‐inchstormeventbetweenadevelopedsiteandthesiteinanundevelopedcondition(i.e.0percentimpervious)wheretechnicallyfeasible. Inaddition,adevelopedsiteisrequiredtotreattheentire0.75‐inchrainfalltoremoveurbanstormwaterpollution.InadditiontotheLIDrequirementssetfortheLIDmanual,theCountyalsoestablisheshydromodificationrequirementsthatrequirethedifferenceinpeakflowrate,flowvelocity,totalvolume,anddepth/widthofflowforthe2‐,5‐,10‐,25‐,and50‐yearstormwithseveralexceptions.Oneexceptionisforproposedprojectsthatdonotaddnetnewimperviousarea.SincetheHarbor‐UCLACampusis fully developed and highly impervious, the hydromodification requirement will likely not apply to theProject.

With the increase in pervious area, an integrated stormwater management approach and theimplementationoftheCountyLIDStandards,therequirementstodetainflowstomeetexistingdesignflowrateswillbeminimized.PeakflowratesandrunoffvolumesfromtheCampuswouldbethesameorlowercomparedtoexistingrates/volumesandwouldnotaffectthecapacityorhydraulicintegrityoftheexistingCountystormdrainsystem.ImpactsrelatedtothevolumeofrunofffromtheHarbor‐UCLACampusonthecapacityoftheCounty’sstormdraininfrastructure,andrelatedtothepotentialforadditionalpollutedrunoffcomparedtoexistingconditions,wouldbelessthansignificant.

ThresholdHWQ‐6:WouldtheProjectotherwisesubstantiallydegradewaterquality?

Impact StatementHWQ‐6:With compliancewith CountyNPDES and LID requirements, the Project is notanticipatedtosubstantiallydegradewaterquality.

(1) Construction

ImpactsHWQ‐1thoughHWQ‐5discusspotential impactsassociatedwiththedegradationofwaterqualityduring construction. During construction, the Project would be required to adhere to the NPDESConstructionGeneralPermittocontrolerosionandprotectwaterquality.Therefore,theProjectwouldnotcreate or contribute runoff that would exceed the capacity of drainage systems or provide substantialsourcesofpollutedrunoff.TherearenoothermethodsbywhichwaterqualitycouldbedegradedasaresultofconstructionontheProjectsite,andimpactswouldbelessthansignificant.



(2) Operation

Impacts HWQ‐1 through HWQ‐5 discuss potential impacts associated with degradation of water qualityduringProjectoperations.PriortothestartofindividualProjectcomponentconstructionactivities,Harbor‐UCLAwouldberequired toprepareandsubmitdrainageplans forCountyapproval,whichwould includepost‐ProjectstructuralandnonstructuralBMPs.TherearenoothermethodsbywhichwaterqualitycouldbedegradedasaresultofoperationsontheProjectsite. ImpactsassociatedwithpotentialdegradationofwaterqualityduringProjectoperationswouldbelessthansignificant.

e. Cumulative Impacts

The geographic scope for cumulative impacts related to water quality and hydrology encompasses theprojectsiteandthelanduseswithina1‐mileradiusoftheProjectsite.OtherprojectsinthegeneralvicinityoftheproposedProject includeavarietyofhousing,(apartments,condos,single‐family),mixed‐use,retail,andofficeandmedicalspaces.Alloftheseprojectshavethepotentialtoresultinconstruction‐periodwaterquality impacts, which could result in cumulatively significant impacts. However, compliance with theConstruction General Permit, SWPPP, and NPDES requirements, and local regulations that requireconstruction phase BMPswould ensure that construction activitieswould not degrade the surfacewaterqualityofreceivingwatersto levelsbelowstandardsconsideredacceptablebytheLosAngelesRWQCBorother regulatory agencies or impair the beneficial uses of the receiving waters. Construction would notresult in a violation of anywater quality standards orwaste discharge requirements, would not providesubstantial additional sources of polluted runoff, and would not substantially degrade water quality.Compliance with construction phase permits and standard construction phase BMPswould decrease thepotentialforanysignificanterosionorsedimentationfromsoildisturbanceassociatedwithconstructionofthe projects. During construction the amount of stormwater runoff is also anticipated to be less than orequal to the amount under existing conditions. Therefore, the cumulative effects would be less thansignificant.

Compliancewith County LID criteria aswell as state and local regulations that require post constructionBMPswouldensure that theoperationof relatedprojectswouldnotdegrade the surfacewaterqualityofreceiving waters to levels below standards considered acceptable by the Los Angeles RWQCB or otherregulatoryagenciesorimpairthebeneficialusesofthereceivingwaters.TheProjectwouldalsoberequiredto comply with all applicable federal, state, and local requirements concerning handling, storage, anddisposalofhazardousmaterialstoreducethepotentialforthereleaseofcontaminantsintogroundwaterasa result of project construction or operation. Therefore, construction and operation activitieswould notdegrade groundwater quality or interfere with recharge and the cumulative effects would be less thansignificant.

4. MITIGATION MEASURES

Potentialimpactsrelatedtohydrologyandwaterqualitywouldbelessthansignificantwithcompliancewithapplicableregulatoryrequirements.Therefore,nomitigationmeasuresarerequired.



5. LEVEL OF SIGNIFICANCE AFTER MITIGATION

Potentialimpactsrelatedtohydrologyandwaterqualitywouldbelessthansignificantwithcompliancewithapplicableregulatoryrequirements.

Documents

Department of Public Works, Los Angeles County - …...August 2016 4.G. Hydrology and Water Quality Los Angeles County Department of Public Works Harbor‐UCLA Medical Center Campus