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STATE

California

CONTAMINANTS

175

serves

68,077,000

data

2013-2024

UTILITIES

2,843

Overview

EWG's drinking water quality report for California shows results of tests conducted by the water utilities in California and provided to EWG by the California State Water Resources Control Board.

LARGE UTILITIES
ALL UTILITIES WITH VIOLATIONS
LARGE UTILITIES WITH VIOLATIONS

Large utilities in California

Below are utilities in California serving over 10,000 people, listed alphabetically.

UtilityLocationPeople Served
Alameda County Water DistrictFremont, CA344,855
Alco Water ServiceSalinas, CA30,103
American Water O&m, Llc - VsfbVandenberg Afb, CA14,971
Antelope Valley - East Kern Water AgencyPalmdale, CA286,142
Apple Valley Ranchos Water CompanyDowney, CA62,890
Arroyo Grande,Water DepartmentArroyo Grande, CA17,963
Arvin Community Services DistrictArvin, CA19,669
Atascadero Mutual Water CompanyAtascadero, CA30,457
Azusa Light and WaterAzusa, CA110,044
Bakman Water CompanyFresno, CA17,393
Beaumont Cherry Valley WDBeaumont, CA49,241
Bella Vista Water DistrictRedding, CA18,612
Bellflower - Somerset MWCBellflower, CA46,300
Beverly Hills Water DepartmentBeverly Hills, CA40,856
Big Bear City CSDBig Bear City, CA12,738
Big Bear Lake Dwp - Big Bear SystemBig Bear Lake, CA12,609
Burbank Water DepartmentBurbank, CA105,451
Cachuma VillageSanta Barbara, CA45,146
Cal American Water CompanyRosemead, CA66,809
Cal-am Water Company - DuarteRosemead, CA24,703
Cal-water Service Company - ChicoSan Jose, CA110,512
Cal-water Service Company - MarysvilleSan Jose, CA12,266
Cal-water Service Company-orovilleSan Jose, CA11,056
Cal/am Water Company - Baldwin HillsRosemead, CA20,859
Cal/Am Water Company - San MarinoRosemead, CA47,731
California American Water Company - AntelopeSacramento, CA35,204
California American Water Company - CoronadoImperial Beach, CA106,000
California American Water Company - Lincoln OaksSacramento, CA47,546
California American Water Company - MontereyPacific Grove, CA92,450
California American Water Company - ParkwaySacramento, CA49,150
California American Water Company - SuburbanSacramento, CA53,757
California Domestic Water CompanyWhittier, CA290,814
California Water Service (CWS) - BakersfieldSan Jose, CA266,213
California Water Service (CWS) - King CitySan Jose, CA16,044
California Water Service (CWS) - Los Altos SuburbanSan Jose, CA70,175
California Water Service (CWS) - North GardenSan Jose, CA22,620
California Water Service (CWS) - SalinasSan Jose, CA113,086
California Water Service (CWS) - SelmaSan Jose, CA26,360
California Water Service (CWS) - VisaliaSan Jose, CA145,793
California Water Service - Bear GulchSan Jose, CA60,903
California Water Service - LivermoreSan Jose, CA60,215
California Water Service - San CarlosSan Jose, CA35,453
California Water Service - San MateoSan Jose, CA102,663
California Water Service - South San FranciscoSan Jose, CA63,439
California Water Service - StocktonSan Jose, CA175,026
California Water Service Co.-travis AFBSan Jose, CA15,971
California Water Service Company - DixonSan Jose, CA10,616
California Water Service Company - DominguezSan Jose, CA143,464
California Water Service Company - East Los AngelesSan Jose, CA151,902
California Water Service Company - Hermosa / Redondo BeachSan Jose, CA96,657
California Water Service Company - Palos VerdeSan Jose, CA70,819
California Water Service Company - WestlakeSan Jose, CA19,512
Calleguas Municipal Water DistrictThousand Oaks, CA640,000
Camarillo Water DepartmentCamarillo, CA46,848
Camp Pendleton (North)Camp Pendleton, CA15,000
Camp Pendleton (South)Camp Pendleton, CA45,000
Camrosa Water DistrictCamarillo, CA32,700
Carlsbad Municipa Water DistrictCarlsbad, CA92,865
Carmichael Water DistrictCarmichael, CA41,193
Carpinteria Valley Water DistrictCarpinteria, CA15,996
Casitas Municipal Water DistrictOak View, CA11,005
CCWD Ebbetts Pass Improvement DistrictSan Andreas, CA11,545
Central Coast Water AuthorityBuellton, CA646,441
Cerritos - City, Water DepartmentCerritos, CA49,578
Chino Basin Desalter Authority - Desalter 2Ontario, CA376,341
Chorro Valley Pipeline - Slo CountySan Luis Obispo, CA30,000
Chowchilla City Water DepartmentChowchilla, CA13,576
Citrus Heights Water DistrictCitrus Heights, CA66,815
City of AdelantoAdelanto, CA39,930
City of AlhambraAlhambra, CA83,750
City of American CanyonAmerican Canyon, CA20,990
City of AnaheimAnaheim, CA341,245
City of AndersonAnderson, CA11,147
City of AntiochAntioch, CA115,074
City of ArcadiaArcadia, CA44,738
City of ArcataArcata, CA20,359
City of AtwaterAtwater, CA29,479
City of AvenalAvenal, CA13,819
City of BakersfieldSan Jose, CA156,770
City of BanningBanning, CA31,179
City of BeniciaBenicia, CA28,000
City of BrawleyBrawley, CA26,928
City Of BreaBrea, CA47,589
City of BrentwoodBrentwood, CA64,342
City of Buena ParkBuena Park, CA81,998
City of BurlingameBurlingame, CA31,919
City of CalexicoCalexico, CA40,357
City of California CityCalifornia City, CA14,198
City of CeresCeres, CA48,706
City of ChinoChino, CA84,560
City of Chino HillsChino Hills, CA77,964
City of ClovisClovis, CA125,722
City of ColtonColton, CA46,525
City of CorcoranCorcoran, CA21,835
City of CoronaCorona, CA168,751
City of Crescent CityCrescent City, CA16,711
City of CupertinoSan Jose, CA16,530
City of Daly CityDaly City, CA108,599
City of DavisDavis, CA67,217
City of DelanoDelano, CA51,428
City of DinubaDinuba, CA26,913
City Of DixonDixon, CA11,784
City of East Palo AltoEast Palo Alto, CA29,519
City of El CentroEl Centro, CA44,158
City of EscondidoEscondido, CA137,941
City of EurekaEureka, CA27,078
City of ExeterExeter, CA11,169
City of FairfieldFairfield, CA119,897
City of FarmersvilleFarmersville, CA10,397
City of FolsomFolsom, CA75,728
City of FortunaWhitethorn, CA12,133
City of Fountain ValleyFountain Valley, CA56,747
City of FresnoFresno, CA545,466
City of FullertonFullerton, CA141,874
City of GaltGalt, CA26,536
City of Garden GroveGarden Grove, CA174,226
City of GilroyGilroy, CA58,108
City of GreenfieldGreenfield, CA18,967
City of HanfordHanford, CA62,127
City of HaywardHayward, CA159,293
City of HealdsburgHealdsburg, CA11,174
City of HemetHemet, CA33,828
City of HollisterHollister, CA23,358
City of Huntington BeachHuntington Beach, CA201,000
City of ImperialImperial, CA21,347
City of InglewoodInglewood, CA82,041
City of KermanKerman, CA16,995
City of KingsburgKingsburg, CA12,380
City of La HabraLa Habra, CA63,118
City of La PalmaLa Palma, CA15,948
City of LathropLathrop, CA35,080
City of LemooreLemoore, CA27,038
City of LincolnLincoln, CA51,252
City of LindsayLindsay, CA12,659
City of LivermoreLivermore, CA35,672
City of LivingstonLivingston, CA14,894
City of LodiLodi, CA68,272
City of Loma LindaLoma Linda, CA24,791
City of Los BanosLos Banos, CA46,639
City of MaderaMadera, CA66,172
City of MantecaManteca, CA84,625
City of MartinezMartinez, CA28,518
City of McFarlandMcfarland, CA15,506
City of MendotaMendota, CA11,404
City of Menlo ParkMenlo Park, CA19,297
City of MercedMerced, CA92,058
City of MillbraeMillbrae, CA22,795
City of MilpitasMilpitas, CA77,961
City of ModestoModesto, CA218,771
City of Modesto, SalidaModesto, CA14,537
City of Morgan HillMorgann Hill, CA47,374
City of Mountain ViewMountain View, CA81,756
City of NapaNapa, CA85,005
City of Newman Water DepartmentNewman, CA12,351
City of Newport BeachNewport Beach, CA68,572
City of NorcoNorco, CA24,909
City of OakdaleOakdale, CA23,235
City of OceansideOceanside, CA173,048
City of OrangeOrange, CA117,150
City of Palo AltoPalo Alto, CA67,973
City of ParlierParlier, CA14,576
City of PattersonPatterson, CA23,304
City of PetalumaPetaluma, CA61,304
City of PittsburgPittsburg, CA62,500
City of PleasantonPleasanton, CA79,871
City of PortervillePorterville, CA62,988
City of PowayPoway, CA49,779
City of Red BluffRed Bluff, CA14,076
City of ReddingRedding, CA87,741
City of Redwood CityRedwood City, CA89,037
City of ReedleyReedley, CA25,227
City of RialtoRialto, CA54,453
City Of Rio VistaRio Vista, CA10,489
City of RiponRipon, CA15,979
City of RiverbankRiverbank, CA24,834
City of RiversideRiverside, CA300,488
City of Rohnert ParkRohnert Park, CA42,484
City of RosevilleRoseville, CA149,859
City of Sacramento MainSacramento, CA520,746
City of San BrunoSan Bruno, CA46,085
City of San ClementeSan Clemente, CA51,545
City of San DiegoSan Diego, CA1,374,790
City of San JacintoSan Jacinto, CA18,950
City of San Jose - EVG/EDV/COYSan Jose, CA98,198
City of San Jose - NSJ/AlvisoSan Jose, CA37,991
City of San Juan CapistranoLas Flores, CA38,958
City of SangerSanger, CA26,241
City of Santa AnaSanta Ana, CA337,716
City of Santa Barbara Water DepartmentSanta Barbara, CA98,420
City of Santa ClaraSanta Clara, CA130,746
City of Santa PaulaSanta Paula, CA30,759
City of Santa RosaSanta Rosa, CA175,775
City of Seal BeachSeal Beach, CA24,937
City of ShafterShafter, CA21,036
City of Shasta LakeShasta Lake, CA10,657
City of SoledadSoledad, CA17,073
City of SonomaSonoma, CA11,725
City of South PasadenaSouth Pasadena, CA25,329
City of StocktonStockton, CA183,046
City of SunnyvaleSunnyvale, CA155,567
City of Torrance Water DepartmentTorrance, CA106,183
City of TracyTracy, CA94,538
City of TulareTulare, CA70,733
City of TurlockTurlock, CA72,682
City of TustinTustin, CA66,600
City of UkiahUkiah, CA16,607
City of UplandUpland, CA78,376
City of VacavilleElmira, CA97,155
City of VallejoVallejo, CA126,090
City of WascoWasco, CA22,608
City of WatsonvilleWatsonville, CA65,231
City of West SacramentoWest Sacramento, CA53,355
City of WestminsterWestminster, CA95,256
City of WoodlandWoodland, CA61,032
City of Yuba CityYuba City, CA75,322
Coachella Valley Water District: Cove CommunityPalm Desert, CA270,000
Coachella Water AuthorityCoachella, CA42,554
CoalingaCoalinga, CA17,277
Coastside County Water DistrictHalf Moon Bay, CA18,789
Compton Water DepartmentCompton, CA74,877
Contra Costa Water DistrictConcord, CA198,000
Covina Irrigating CompanyCovina, CA369,059
Covina Water DepartmentCovina, CA33,300
Crescenta Valley CWDLa Crescenta, CA32,665
Crestline Village County Water District - Division 10Crestline, CA10,030
Cucamonga Valley Water DistrictRancho Cucamonga, CA202,248
Del Oro Water Company - Paradise PinesChico, CA10,900
Desert Water AgencyPalm Springs, CA57,507
Diablo Water DistrictOakley, CA43,357
Downey Water DepartmentDowney, CA109,946
Dublin San Ramon Services DistrictDublin, CA98,776
East Bay Municipal Utility DistrictOakland, CA1,430,200
East Niles CSDBakersfield, CA32,517
East Orange County Water District - WzOrange, CA75,236
East Valley Water DistrictHighland, CA103,758
Eastern Municipal Water DistrictPerris, CA637,387
El Dorado ID - MainPlacerville, CA131,527
El Monte Water DepartmentEl Monte, CA22,968
El Segundo Water DepartmentEl Segundo, CA16,898
El Toro Water DistrictLake Forest, CA47,911
Elk Grove Water ServiceElk Grove, CA42,556
Elsinore Valley Municipal Water DistrictLake Elsinore, CA165,586
Estero Municipal Improvement DistrictFoster City, CA36,556
Fair Oaks Water DistrictFair Oaks, CA35,377
Fallbrook PUDFallbrook, CA35,237
Fillmore Water DepartmentFillmore, CA16,419
Fruitridge Vista Water CompanySacramento, CA15,167
Glendale Water DepartmentGlendale, CA201,334
Glendora Water DepartmentGlendora, CA52,558
Golden State Water Company (GSWC) - ArtesiaSanta Fe Springs, CA50,230
Golden State Water Company (GSWC) - Bell, Bell GardensSanta Fe Springs, CA54,309
Golden State Water Company (GSWC) - ClaremontSan Dimas, CA39,279
Golden State Water Company (GSWC) - Culver CitySanta Fe Springs, CA38,029
Golden State Water Company (GSWC) - Florence/GrahamSanta Fe Springs, CA62,970
Golden State Water Company (GSWC) - NorwalkSanta Fe Springs, CA42,997
Golden State Water Company (GSWC) - San DimasSan Dimas, CA56,426
Golden State Water Company (GSWC) - South ArcadiaSan Dimas, CA26,688
Golden State Water Company (GSWC) - South San GabrielSan Dimas, CA25,907
Golden State Water Company (GSWC) - SouthwestHawthorne, CA275,369
Golden State Water Company (GSWC) -WillowbrookSanta Fe Springs, CA10,615
Golden State Water Company - BarstowApple Valley, CA32,328
Golden State Water Company - Bay PointRancho Cordova, CA23,693
Golden State Water Company - CordovaRancho Cordova, CA47,060
Golden State Water Company - OrcuttRancho Cordova, CA33,364
Golden State Water Company - SimiRancho Cordova, CA44,640
Golden State Water Company - West OrangeAnaheim, CA113,106
Golden State WC - PlacentiaAnaheim, CA49,808
Goleta Water DistrictGoleta, CA84,462
Great Oaks Water Company Inc.San Jose, CA108,902
Greenfield County Water DistrictBakersfield, CA11,411
Grover Beach Water DepartmentGrover Beach, CA12,701
Hawthorne Water DepartmentSan Jose, CA44,729
Helix Water DistrictLakeside, CA277,418
Hesperia Water DistrictHesperia, CA100,324
Hi Desert WDYucca Valley, CA26,032
Hillsborough Water DepartmentHillsborough, CA11,387
Humboldt CSDCutten, CA19,726
Huntington Park Water DepartmentHuntington Park, CA15,275
Indian Wells Valley WDRidgecrest, CA39,478
Indio Water AuthorityIndio, CA82,668
Irvine Ranch Water DistrictIrvine, CA468,941
Jurupa Community Services DistrictJurupa Valley, CA133,292
Kern County Water AgencyBakersfield, CA185,000
La Verne WDLa Verne, CA32,206
Laguna Beach County WDLaguna Beach, CA18,401
Lake Hemet Municipal Water DistrictHemet, CA52,913
Lakeside WDLakeside, CA35,500
Lakewood Water DepartmentLakewood, CA63,066
Lamont Public Utility DistrictLamont, CA19,057
Las Virgenes Municipal Water DistrictCalabasas, CA72,602
Liberty Utilities - Bellflower - NorwalkDowney, CA72,964
Lincoln Avenue Water CompanyAltadena, CA16,126
Linda County Water DistrictMarysville, CA21,654
Lomita Water DepartmentLomita, CA20,256
Lompoc City Water Utility DivisionLompoc, CA41,079
Long Beach UtilitiesDepartmentLong Beach, CA460,682
Lopez ProjectSan Luis Obispo, CA47,708
Los Angeles County WW District 29 & 80-MalibAlhambra, CA32,719
Los Angeles County WW District 4 & 34-LancasterAlhambra, CA204,393
Los Angeles County WW District 40 Reg 38 Lake Los AngelesAlhambra, CA12,620
Los Angeles CWWD 40, R24, 27,33-PearblsmAlhambra, CA11,183
Los Angeles Department of Water and PowerLos Angeles, CA3,868,811
Lynwood Water DepartmentLynwood, CA66,967
Manhattan Beach Water DepartmentManhattan Beach, CA34,668
Marin Municipal Water DistrictCorte Madera, CA193,937
Marina Coast Water DistrictMarina, CA36,214
McKinleyville CSDMckinleyville, CA16,900
Mesa Water DistrictCosta Mesa, CA110,000
Metropolitan Water District of So. Cal.La Verne, CA18,606,473
Mid-Peninsula Water DistrictBelmont, CA28,050
Mission Springs WDDesert Hot Springs, CA43,223
Modesto Irrigation DistrictModesto, CA218,790
Mojave Water AgencyApple Valley, CA316,866
Monrovia Water DepartmentMonrovia, CA37,787
Monte Vista Water DistrictMontclair, CA56,422
Montebello Land & Water CompanyMontebello, CA26,554
Montecito Water DistrictSanta Barbara, CA11,881
Monterey Park Water DepartmentMonterey Park, CA62,183
Morro Bay PW Department - Water DivisionMorro Bay, CA10,581
Moulton Niguel Water DistrictLaguna Hills, CA170,236
Mountain House Community Services DistrictMountain House, CA24,040
Muscoy Mutual Water Company No. 1San Bernardino, CA13,000
Nevada ID - E. George, Banner MountainGrass Valley, CA17,154
Nevada ID - Loma RicaGrass Valley, CA14,072
Newhall CWD-NewhallSanta Clarita, CA17,154
Nipomo Comm. Services DistrictNipomo, CA13,771
North Coast County Water DistrictPacifica, CA38,546
North Marin Water DistrictNovato, CA61,683
Norwalk Water DepartmentNorwalk, CA17,790
Oak Park Water ServiceWestlake Village, CA13,898
Oildale MWCBakersfield, CA39,756
Olivehurst Public UDOlivehurst, CA16,595
Olivenhain Municipal Water DistrictEncinitas, CA86,614
Ontario Municipal Utilities CompanyOntario, CA185,010
Orange Vale Water CompanyOrangevale, CA16,861
Orchard Dale Water DistrictWhittier, CA25,000
Otay Water DistrictSpring Valley, CA227,957
Oxnard Water DepartmentOxnard, CA200,232
Padre Dam Municipal Water DistrictSantee, CA88,963
Palmdale Water DistrictPalmdale, CA126,994
Paramount Water DepartmentParamount, CA55,200
Park Water Company - Bell GardensDowney, CA11,292
Park WC - ComptonDowney, CA23,802
Park WC - LynwoodDowney, CA24,171
Pasadena Water and PowerPasadena, CA170,950
Paso Robles Water DepartmentPaso Robles, CA31,221
Phelan Pinon Hills CSDPhelan, CA23,585
Pico Rivera Water DepartmentPico Rivera, CA40,600
Pico WDPico Rivera, CA22,051
Pinedale County Water DistrictPinedale, CA16,735
Placer County Water Agency - FoothillAuburn, CA89,008
Placer CWA - Auburn/BowmanAuburn, CA26,267
Plumas LakeOlivehurst, CA10,464
Pomona Water DepartmentPomona, CA151,713
Port Hueneme Water AgencyPort Hueneme, CA41,679
Port Hueneme Water DepartmentPort Hueneme, CA21,954
Quartz Hill Water DistrictQuartz Hill, CA19,100
Rainbow Municipal WDFallbrook, CA23,536
Ramona Municipal WDRamona, CA35,135
Rancho California Water DistrictTemecula, CA144,088
Randall-bold Water Treatment PlantOakley, Ca, CA30,000
Redlands CityRedlands, CA78,025
Rincon Del Diablo MWD(ID-1)Escondido, CA29,206
Rio Linda/Alverta Community Water DistrictRio Linda, CA15,404
Riverside Highland Water CompanyGrand Terrace, CA19,503
Rosamond CSDRosamond, CA17,516
Rowland Water DistrictRowland Heights, CA54,660
Rubidoux Community SDJurupa Valley, CA36,827
Sacramento County Water Agency - Arden Park VistaSacramento, CA10,035
Sacramento County Water Authority - Laguna/VineyardSacramento, CA176,926
Sacramento Suburban Water DistrictSacramento, CA194,444
San Bernardino CitySan Bernardino, CA204,870
San Bernardino Valley Water DistrictSan Bernardino, CA109,608
San Diego County Water AuthoritySan Diego, CA3,276,208
San Dieguito WDEncinitas, CA40,103
San Fernando Water DepartmentSan Fernando, CA23,946
San Francisco City Water SystemBurlingame, CA800,000
San Gabriel County WDRosemead, CA45,000
San Gabriel Valley Water Company - FontanaEl Monte, CA237,300
San Gabriel Valley Water Company- El MonteEl Monte, CA254,300
San Jose State UniversitySan Jose, CA30,000
San Jose Water CompanySan Jose, CA1,007,514
San Juan Basin AuthorityLas Flores, CA38,958
San Juan Water DistrictGranite Bay, CA28,971
San Lorenzo Valley Water DistrictBoulder Creek, CA21,145
San Luis Obispo Water DepartmentSan Luis Obispo, CA47,653
Santa Clara Valley Water DistrictSan Jose, CA1,934,171
Santa Clarita Valley W.a.-imported DivisNewhall, CA294,639
Santa Clarita Valley W.a.-pinetree Div.Santa Clarita, CA15,713
Santa Clarita Valley Water Authority - Valencia Water DivisionNewhall, CA110,329
Santa Clarita Water DivisionNewhall, CA135,022
Santa Cruz Water DepartmentSanta Cruz, CA95,939
Santa Fe IDRancho Santa Fe, CA21,539
Santa Fe Springs Water DepartmentSanta Fe Springs, CA19,219
Santa Margarita Water DistrictLas Flores, CA164,604
Santa Maria Water DepartmentSanta Maria, CA109,910
Santa MonicaSanta Monica, CA93,076
SBDNO County Service Area 64San Bernardino, CA14,863
SBNDO County Service Area 70JSan Bernardino, CA12,721
Scotts Valley Water DistrictScotts Valley, CA10,709
SCWA Mather-SunriseSacramento, CA25,988
SFWP - Miners RanchOroville, CA22,727
Sierra Madre Water DepartmentSierra Madre, CA11,000
Signal Hill - City, Water DepartmentSignal Hill, CA11,795
Sonoma State UniversityRohnert Park, CA10,986
Soquel Creek Water DistrictSoquel, CA40,644
South Coast Water District - South CoastLaguna Beach, CA34,724
South Gate Water DepartmentSouth Gate, CA76,443
South Mesa Water CompanyCalimesa, CA10,061
South Montebello Irrigation DistrictMontebello, CA15,021
South San Joaquin Irrigation DistrictRipon, CA212,000
South Tahoe PUD - MainSouth Lake Tahoe, CA21,414
Stanford UniversityStanford, CA32,235
Stockton East Water DistrictStockton, CA364,624
Suburban Water Systems - La MiradaCovina, CA56,793
Suburban Water Systems - San Jose HillsCovina, CA168,843
Suburban Water Systems - WhittierCovina, CA66,045
Suisun-Solano Water AuthorityVacaville, CA29,530
Sunny Slope Water CompanyPasadena, CA25,252
Sunnyslope County Water DistrictHollister, CA23,499
Sweetwater AuthorityChula Vista, CA189,371
Temescal Valley Water DistrictTemescal Valley, CA20,526
Thermalito Water & Sewer DistrictOroville, CA12,136
Thousand Oaks Water DepartmentThousand Oaks, CA53,157
Three Valleys Municipal Water DistrictClaremont, CA67,018
Town of Discovery BayDiscovery Bay, CA16,790
Trabuco Canyon Water DistrictTrabuco Canyon, CA13,659
Tract 180 Mutual Water CompanyCudahy, CA14,000
Truckee-Donner PUD, MainTruckee, CA36,730
TUD - Sonora/Jamestown Water SystemSonora, CA10,814
Tud - Upper Basin Water SystemSonora, CA10,702
Twentynine Palms Water DistrictTwentynine Palms, CA18,795
UC - DavisDavis, CA48,828
United Water Cons DistrictOxnard, CA240,000
US Army Fort IrwinFort Irwin, CA16,000
USMC - 29 Palms29 Palms, CA17,033
Vallecitos Water DistrictSan Marcos, CA111,000
Valley Center MWDValley Center, CA29,708
Valley County Water DistrictBaldwin Park, CA68,714
Valley of The Moon Water DistrictEl Verano, CA23,077
Valley Water CompanyLa Canada Flintridge, CA10,070
Vaughn WC IncBakersfield, CA36,644
Ventura CWWD No. 1 - MoorparkMoorpark, CA36,625
Ventura Water DepartmentVentura, CA110,763
Ventura Waterworks District No. 8 - Simi ValleySimi Valley, CA94,738
Vernon Water DepartmentVernon, CA28,000
Victorville Water DistrictVictorville, CA124,653
Vista Irrigation DistrictVista, CA132,838
Walnut Park Mutual Water CompanyHuntington Park, CA16,180
Walnut Valley Water DistrictWalnut, CA100,449
West End Consolidated Water CompanyUpland, CA78,891
West Kern Water DistrictTaft, CA19,832
West Valley Water DistrictRialto, CA98,055
Westborough County Water DistrictSouth San Francisco, CA13,486
Western Municipal Water DistrictRiverside, CA82,560
Western Municipal Water District - Murrieta DivisionRiverside, CA16,373
Western MWD (Arlington)Riverside, CA27,840
Whittier Water DepartmentWhittier, CA49,954
WindsorWindsor, CA28,397
Woodland-davis Clean Water AgencyWoodland, CA129,820
Yorba Linda Water DistrictPlacentia, CA84,054
Yucaipa Valley Water DistrictYucaipa, CA51,900

Utilities that accumulated/accrued the most violation points as of July 2021 to June 2024 in California

The Environmental Protection Agency's Enforcement and Compliance History Online (ECHO) database collects compliance and enforcement-related information for drinking water utilities nationwide. ECHO water quality violation scores take into account federal health-based water quality standards, as well as monitoring, reporting and other drinking water quality requirements. Points are accrued based on specific problems at the utility - violations of health-based drinking water standards receive more points than monitoring and reporting violations - and the length of time until the violations were corrected.

UtilityLocationPeople ServedViolation Points
Twin Valley Inc.San Jose, CA317350
Rainbird Valley Mutual Water CompanyWeldon, CA238260
Pauma Valley Water CompanyPauma Valley, CA193235
Encinal Rd. Ws #01Salinas, CA41210
R.s. Mutual Water CompanyWofford Heights, CA67200
Lemon Cove Water CompanyLemon Cove, CA109200
Springfield Water CompanyRoyal Oaks, CA200190
River Rd. Ws #25Gonzales, CA65190
Sierra Vista AssociationClovis, CA44181
Valley Ford Water AssociationValley Ford, CA61175
Knoll EnterprisesLudlow, CA500171
Hillcrest Mobile EstatesLos Angeles, CA493170
Quiet Oaks Mobile Home ParkStockton, CA120161
North Davis MeadowsWoodland, CA314160
Lake Morena Views Mw CompanyCampo, CA360160
Ramona Water CompanyAnza, CA250150
Brock Mutual Water CompanyBakersfield, CA462150
Son Shine PropertiesEdison, CA438150
Wilson Road Water CommunityBakersfield, CA66140
Higuera ApartmentsSan Luis Obispo, CA30140
Md 42 Still MeadowMadera, CA100135
Del Oro River Island Serv Terr #1Chico, CA1,205135
San Joaquin Estates Mutual Water CompanyBakersfield, CA165130
Oak Heights W & R Co. Inc.Salinas, CA105130
Del Oro Grandview Gardens DistrictChico, CA320120
Mccoy Rd. Ws #05Salinas, CA72120
Tipton Community Services DistrictTipton, CA2,543120
Mettler County Water DistrictBakersfield, CA157110
Sierra Linda Mutual Water CompanyNorth Fork, CA200105
East Orosi Community Services DistrictVisalia, CA423102

Large utilities that accumulated/accrued the most violation points as of July 2021 to June 2024 in California

The Environmental Protection Agency's Enforcement and Compliance History Online (ECHO) database collects compliance and enforcement-related information for drinking water utilities nationwide. ECHO water quality violation scores take into account federal health-based water quality standards, as well as monitoring, reporting and other drinking water quality requirements. Points are accrued based on specific problems at the utility - violations of health-based drinking water standards receive more points than monitoring and reporting violations - and the length of time until the violations were corrected.

UtilityLocationPeople ServedViolation Points
City of LemooreLemoore, CA27,038100
City of LindsayLindsay, CA12,65990
Suisun-Solano Water AuthorityVacaville, CA29,53025
CCWD Ebbetts Pass Improvement DistrictSan Andreas, CA11,54520
City of AvenalAvenal, CA13,81920
City of McFarlandMcfarland, CA15,50611
Casitas Municipal Water DistrictOak View, CA11,0055
City of KingsburgKingsburg, CA12,3805
Ventura Waterworks District No. 8 - Simi ValleySimi Valley, CA94,7385
Signal Hill - City, Water DepartmentSignal Hill, CA11,7952
City of StocktonStockton, CA183,0461
City of HanfordHanford, CA62,1271
Montebello Land & Water CompanyMontebello, CA26,5541
City of HollisterHollister, CA23,3581
City of American CanyonAmerican Canyon, CA20,9901
Temescal Valley Water DistrictTemescal Valley, CA20,5261
Pinedale County Water DistrictPinedale, CA16,7351
City of UkiahUkiah, CA16,6071
Fillmore Water DepartmentFillmore, CA16,4191
City of California CityCalifornia City, CA14,1981
Montecito Water DistrictSanta Barbara, CA11,8811

Contaminants found in California above health guidelines

Found above health guidelines Found
Contaminant # of Utilities People Served # of Utilities People Served
Arsenic1,48254,538,9331,48254,538,933
Nitrate1,71752,699,3822,10059,491,982
Uranium, combined (pCi/L)90746,836,8371,07256,026,073
Nitrate & nitrite98246,513,7921,14253,159,592
Haloacetic acids (HAA5)1,88244,274,1631,88244,274,163
Total trihalomethanes (TTHMs)1,53543,658,7431,56144,501,980
Chromium (hexavalent)68938,615,40276745,095,892
Haloacetic acids (HAA9)50636,298,14451036,456,033
Bromodichloromethane1,33435,188,7171,35735,924,337
Dibromochloromethane1,30233,874,4941,37635,977,838
Dichloroacetic acid98730,669,2981,09333,555,836
Chloroform1,01730,360,2901,23134,977,868
Dibromoacetic acid1,12330,283,5011,15332,817,310
Trichloroacetic acid93429,526,77998731,704,177
Bromoform93126,574,6111,23833,644,235
Perfluorohexane sulfonate (PFHXS)27317,935,02527317,935,025
Bromate9117,325,0319717,334,573
Perfluorooctanoic acid (PFOA)23114,478,43427118,395,374
Perfluorooctane sulfonate (PFOS)22714,391,18128822,697,091
Perfluorononanoic acid (PFNA)724,880,471755,189,120
Radium, combined (-226 & -228)3024,680,06945530,046,189
Tetrachloroethylene (perchloroethylene)803,157,02412110,416,014
1,2-Dibromo-3-chloropropane (DBCP)772,307,4951033,484,599
Perfluorodecanoic acid (PFDA)311,938,972311,938,972
Bromochloroacetic acid521,880,641521,880,641
1,4-Dioxane341,712,80519819,194,328
Chlorite81,694,11881,694,118
1,2,3-Trichloropropane1131,598,8492166,218,615
Radon391,566,568391,566,568
Bromochloromethane251,326,97712413,639,300
Trichloroethylene21730,540858,958,848
Perfluoropentane sulfonic acid (PFPeS)13557,939372,821,662
Perfluoroheptane sulfonic acid (PFHpS)8481,5008481,500
Carbon tetrachloride6316,28912395,289
Perchlorate31260,63119610,914,164
Vanadium15257,8961,02664,263,185
Manganese168207,5271,61064,294,912
Chlorate14186,92852442,386,792
Cadmium3150,5833452,447
Benzene229,5855113,905
Molybdenum318,14546435,711,069
6:2 Fluorotelomer Sulfonic Acid (6:2 FTSA)215,27010821,556
Perfluorododecanoic acid (PFDoA)412,814412,814
Hexachlorobenzene (HCB)112,738112,738
N-Nitrosodimethylamine (NDMA)12,640183,677,851
Thallium51,92112313,223
Selenium61,0515119,559,009
Perfluorotetradecanoic acid (PFTA)25252525
Perfluorotridecanoic acid (PFTrDA)25252525
Perfluoroundecanoic acid (PFUnA)25252525
Antimony44804068,569
Strontium-90245311203,868
Aluminum130072443,987,079
Ethylene dibromide1290698,366
Mercury (inorganic)15042267,502
Simazine146429,545

Contaminants found in California above legal limits

Contaminant # of Utilities People Served

Arsenic		94207,431

Total trihalomethanes (TTHMs)		2353,827

Nitrate		4050,658

Nitrate and nitrite		2843,249

Uranium		2726,606

Tetrachloroethylene (perchloroethylene)		310,093

Selenium		71,238

Antimony		1297

Ethylene dibromide		1290

Fluoride		2270

Chromium (total)		1108

1,2-Dibromo-3-chloropropane (DBCP)		294

Mercury (inorganic)		150

What filter type is right for you?

Water
Contaminants

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Carbon Filters

Can reduce the levels of many common contaminants.

pros

  • Lower upfront cost
  • Reduced maintenance

cons

  • Does not remove all contaminants

Reverse Osmosis

Most effective at reducing contaminants.

pros

  • Most effective

cons

  • Higher upfront cost
  • Requires more maintenance
  • Wastes water

Other Considerations

Ion Exchange

Pros: Softens hard water, Reduces some contaminants

Cons: Doesn't remove all contaminants

Whole-House Filters

Pros: Useful for reducing radiologicals and TCE

Cons: Expensive to install and maintain, Risk of bacterial contamination

Distillation

Pros: Removes heavy metals and harmful microbes

Cons: Does not reduce most contaminants

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