2026 WATER QUALITY INTELLIGENCE
California Water Quality
Water quality across 342 cities in California, drawn from EPA drinking-water records. Each city page shows the measured contaminants and a reproducible Purity Score.
Review the state record Why no state score?
Explore the evidence geographically
California on the water intelligence map
Open the national map to locate published city reports and inspect the underlying place records. Map coverage is not a statewide safety assessment.
341
water systems in the record
342
published city reports
8
contaminant patterns reported
Not published
published monitoring coverage
UPDATED 2026-09-16
record last updated
How to read this report
PurityMap tracks 342 cities and 341 public water systems in California. Scores reflect only what has been measured; a contaminant that was never tested is shown as pending, never as a pass.
What is being reported in California?
ContaminantCity reports with a published record
Lead342Hard water342PFOA (forever chemical)338PFOS (forever chemical)338PFHxS (forever chemical)338Disinfectant type337Nitrate9Arsenic5Major water sources
Water-source summary not published
Source-water information varies by supplier and reporting period. Use a water-system record for the source description tied to a local utility.
Browse water systemsExplore California city reports
These reports are presented as a directory, not a ranking. Open a city to see its supplier, measurements, interpretation and source documents.
CityKey finding on recordReport
AdelantoPFOA (forever chemical)View report Alameda County DistrictPFOA (forever chemical)View report AlhambraPFOA (forever chemical)View report American CanyonPFOA (forever chemical)View report AnaheimPFOA (forever chemical)View report AndersonLeadView report AntiochPFOA (forever chemical)View report ArcadiaPFOA (forever chemical)View report ArcataPFOA (forever chemical)View report Arroyo GrandePFOA (forever chemical)View report Arvin Community DistPFOA (forever chemical)View report AtwaterPFOA (forever chemical)View report AvenalPFOA (forever chemical)View report Azusa LightPFOA (forever chemical)View report BakersfieldPFOA (forever chemical)View report BanningPFOA (forever chemical)View report Beaumont Cherry Valley WdPFOA (forever chemical)View report Bell GardensPFOA (forever chemical)View report Bella Vista DistrictPFOA (forever chemical)View report BeniciaPFOA (forever chemical)View report Beverly HillsPFOA (forever chemical)View report Big Bear City CsdPFOA (forever chemical)View report Big Bear Lake Dwp - Big BearPFOA (forever chemical)View report BrawleyPFOA (forever chemical)View report BreaPFOA (forever chemical)View report BrentwoodPFOA (forever chemical)View report Buena ParkPFOA (forever chemical)View report BurbankPFOA (forever chemical)View report BurlingamePFOA (forever chemical)View report CalexicoPFOA (forever chemical)View report California CityPFOA (forever chemical)View report CamarilloPFOA (forever chemical)View report Camrosa DistrictPFOA (forever chemical)View report Carlsbad MwdPFOA (forever chemical)View report Carmichael DistrictPFOA (forever chemical)View report Carpinteria Valley DistrictPFOA (forever chemical)View report Casitas DistPFOA (forever chemical)View report Ccwd - Ebbetts PassPFOA (forever chemical)View report CeresPFOA (forever chemical)View report CerritosPFOA (forever chemical)View report ChinoPFOA (forever chemical)View report Chino HillsPFOA (forever chemical)View report ChowchillaPFOA (forever chemical)View report Citrus Heights DistrictPFOA (forever chemical)View report CloverdalePFOA (forever chemical)View report ClovisPFOA (forever chemical)View report CoachellaPFOA (forever chemical)View report Coachella Vwd: Cove CommunityPFOA (forever chemical)View report CoalingaPFOA (forever chemical)View report Coastside County DistrictPFOA (forever chemical)View report ColtonPFOA (forever chemical)View report ComptonPFOA (forever chemical)View report Contra Costa DistrictPFOA (forever chemical)View report CorcoranPFOA (forever chemical)View report CoronaPFOA (forever chemical)View report CovinaPFOA (forever chemical)View report Crescent CityPFOA (forever chemical)View report Crescenta Valley CwdPFOA (forever chemical)View report Crestline Village CwdPFOA (forever chemical)View report Cucamonga Valley DistrictPFOA (forever chemical)View report CupertinoPFOA (forever chemical)View report Daly CityPFOA (forever chemical)View report DavisPFOA (forever chemical)View report DelanoPFOA (forever chemical)View report Desert AgencyPFOA (forever chemical)View report Diablo DistrictPFOA (forever chemical)View report DinubaPFOA (forever chemical)View report Discovery BayPFOA (forever chemical)View report DixonPFOA (forever chemical)View report DowneyPFOA (forever chemical)View report Dublin San Ramon DistrictPFOA (forever chemical)View report East Bay MudPFOA (forever chemical)View report East Niles CsdPFOA (forever chemical)View report East Palo AltoPFOA (forever chemical)View report East Valley DistrictPFOA (forever chemical)View report Eastern WdPFOA (forever chemical)View report El CentroPFOA (forever chemical)View report El Dorado Id -PFOA (forever chemical)View report El MontePFOA (forever chemical)View report El SegundoPFOA (forever chemical)View report El Toro DistrictPFOA (forever chemical)View report Elsinore Valley MwdPFOA (forever chemical)View report EscondidoPFOA (forever chemical)View report Estero Improvement DistrictPFOA (forever chemical)View report EurekaPFOA (forever chemical)View report ExeterLeadView report Fair Oaks DistrictPFOA (forever chemical)View report FairfieldPFOA (forever chemical)View report Fallbrook PudPFOA (forever chemical)View report FarmersvillePFOA (forever chemical)View report FillmorePFOA (forever chemical)View report FolsomPFOA (forever chemical)View report FontanaPFOA (forever chemical)View report FortunaPFOA (forever chemical)View report Fountain ValleyPFOA (forever chemical)View report FresnoPFOA (forever chemical)View report FullertonPFOA (forever chemical)View report GaltLeadView report Garden GrovePFOA (forever chemical)View report GilroyPFOA (forever chemical)View report GlendalePFOA (forever chemical)View report GlendoraPFOA (forever chemical)View report Goleta DistrictPFOA (forever chemical)View report GreenfieldPFOA (forever chemical)View report Greenfield County WdPFOA (forever chemical)View report Grover BeachPFOA (forever chemical)View report HanfordPFOA (forever chemical)View report HawthornePFOA (forever chemical)View report HaywardPFOA (forever chemical)View report HealdsburgPFOA (forever chemical)View report Helix DistrictPFOA (forever chemical)View report HemetPFOA (forever chemical)View report Hesperia WdPFOA (forever chemical)View report Hi Desert WdPFOA (forever chemical)View report HillsboroughPFOA (forever chemical)View report HollisterPFOA (forever chemical)View report Humboldt C S DPFOA (forever chemical)View report Huntington BeachPFOA (forever chemical)View report Huntington ParkPFOA (forever chemical)View report ImperialPFOA (forever chemical)View report Indian Wells Valley W DPFOA (forever chemical)View report IndioPFOA (forever chemical)View report InglewoodPFOA (forever chemical)View report Irvine Ranch DistrictPFOA (forever chemical)View report Jurupa Community SdPFOA (forever chemical)View report KermanPFOA (forever chemical)View report KingsburgPFOA (forever chemical)View report La HabraPFOA (forever chemical)View report La PalmaPFOA (forever chemical)View report La Verne City WdPFOA (forever chemical)View report Laguna Beach County WdPFOA (forever chemical)View report Lake Hemet MwdPFOA (forever chemical)View report LakewoodPFOA (forever chemical)View report Lamont DistPFOA (forever chemical)View report Las Virgenes MwdPFOA (forever chemical)View report LathropPFOA (forever chemical)View report LemoorePFOA (forever chemical)View report LincolnPFOA (forever chemical)View report Linda County DistrictPFOA (forever chemical)View report LindsayPFOA (forever chemical)View report LivermorePFOA (forever chemical)View report LivingstonPFOA (forever chemical)View report LodiPFOA (forever chemical)View report Loma LindaPFOA (forever chemical)View report LomitaPFOA (forever chemical)View report Lompoc-city DivPFOA (forever chemical)View report Long BeachPFOA (forever chemical)View report Los AngelesPFOA (forever chemical)View report Los Angeles Cwwd 29 80-malibuLeadView report Los Angeles Cwwd 40 R 24 27 33-pearblsmPFOA (forever chemical)View report Los Angeles Cwwd 40 Reg 38-lake LaPFOA (forever chemical)View report Los Angeles Cwwd 40 Reg 4 34 LancasterPFOA (forever chemical)View report Los Angeles-city PowerPFOA (forever chemical)View report Los BanosPFOA (forever chemical)View report LynwoodPFOA (forever chemical)View report MaderaPFOA (forever chemical)View report Manhattan BeachPFOA (forever chemical)View report MantecaPFOA (forever chemical)View report Marin DistrictPFOA (forever chemical)View report Marina Coast DistrictPFOA (forever chemical)View report MartinezPFOA (forever chemical)View report McFarlandPFOA (forever chemical)View report Mckinleyville C S DPFOA (forever chemical)View report MendotaPFOA (forever chemical)View report Menlo ParkPFOA (forever chemical)View report MercedPFOA (forever chemical)View report Mesa DistrictPFOA (forever chemical)View report Mid-peninsula DistrictPFOA (forever chemical)View report MillbraePFOA (forever chemical)View report MilpitasPFOA (forever chemical)View report Mission Springs WdPFOA (forever chemical)View report ModestoPFOA (forever chemical)View report Modesto - SalidaPFOA (forever chemical)View report MonroviaPFOA (forever chemical)View report Monte Vista WdPFOA (forever chemical)View report Montecito DistPFOA (forever chemical)View report Monterey ParkPFOA (forever chemical)View report Morgan HillPFOA (forever chemical)View report Morro Bay Pw -PFOA (forever chemical)View report Moulton Niguel DistrictPFOA (forever chemical)View report Mountain HousePFOA (forever chemical)View report Mountain ViewPFOA (forever chemical)View report NapaPFOA (forever chemical)View report Nevada Id - E George Banner MountainPFOA (forever chemical)View report Nevada Id - Loma RicaPFOA (forever chemical)View report NewmanPFOA (forever chemical)View report Newport BeachPFOA (forever chemical)View report Nipomo Comm DistPFOA (forever chemical)View report NorcoPFOA (forever chemical)View report North Coast County DistPFOA (forever chemical)View report North Marin DistrictPFOA (forever chemical)View report Northstar C S DPFOA (forever chemical)View report NorwalkPFOA (forever chemical)View report OakdalePFOA (forever chemical)View report OceansidePFOA (forever chemical)View report Olivehurst U DPFOA (forever chemical)View report Olivenhain MwdPFOA (forever chemical)View report OntarioPFOA (forever chemical)View report OrangePFOA (forever chemical)View report Orchard Dale DistrictPFOA (forever chemical)View report Otay DistrictPFOA (forever chemical)View report OxnardPFOA (forever chemical)View report Padre Dam MwdPFOA (forever chemical)View report Palmdale DistPFOA (forever chemical)View report Palo AltoPFOA (forever chemical)View report ParamountPFOA (forever chemical)View report ParlierPFOA (forever chemical)View report Pasadena PowerPFOA (forever chemical)View report Paso RoblesPFOA (forever chemical)View report PattersonPFOA (forever chemical)View report PetalumaPFOA (forever chemical)View report Phelan Pinon Hills CsdPFOA (forever chemical)View report Pico RiveraPFOA (forever chemical)View report Pico WdPFOA (forever chemical)View report Pinedale County DistrictPFOA (forever chemical)View report PittsburgPFOA (forever chemical)View report Placer Cwa - Auburn/bowmanPFOA (forever chemical)View report Placer Cwa - FoothillPFOA (forever chemical)View report PleasantonPFOA (forever chemical)View report Plumas LakePFOA (forever chemical)View report PomonaPFOA (forever chemical)View report Port HuenemePFOA (forever chemical)View report PortervillePFOA (forever chemical)View report PowayPFOA (forever chemical)View report Quartz Hill DistPFOA (forever chemical)View report Rainbow WdPFOA (forever chemical)View report Ramona WdPFOA (forever chemical)View report Rancho California DistrictPFOA (forever chemical)View report Red BluffPFOA (forever chemical)View report ReddingPFOA (forever chemical)View report Redlands City Mud-water DivPFOA (forever chemical)View report Redwood CityPFOA (forever chemical)View report ReedleyPFOA (forever chemical)View report RialtoPFOA (forever chemical)View report Rincon Del Diablo Mwd IdPFOA (forever chemical)View report Rio Linda/elverta Community DistPFOA (forever chemical)View report Rio VistaPFOA (forever chemical)View report RiponPFOA (forever chemical)View report RiverbankPFOA (forever chemical)View report RiversidePFOA (forever chemical)View report Rohnert ParkPFOA (forever chemical)View report Rosamond CsdPFOA (forever chemical)View report RosevillePFOA (forever chemical)View report Rowland DistrictPFOA (forever chemical)View report Rubidoux Community SdPFOA (forever chemical)View report SacramentoPFOA (forever chemical)View report Sacramento Suburban DistrictPFOA (forever chemical)View report San BernardinoPFOA (forever chemical)View report San BrunoPFOA (forever chemical)View report San ClementePFOA (forever chemical)View report San DiegoPFOA (forever chemical)View report San Dieguito WdPFOA (forever chemical)View report San FernandoPFOA (forever chemical)View report San Gabriel County WdPFOA (forever chemical)View report San JacintoPFOA (forever chemical)View report San Jose - Evg/edv/coyPFOA (forever chemical)View report San Jose - Nsj/alvisoPFOA (forever chemical)View report San Juan DistrictPFOA (forever chemical)View report San Lorenzo Valley DistPFOA (forever chemical)View report San Luis ObispoPFOA (forever chemical)View report SangerPFOA (forever chemical)View report Santa AnaPFOA (forever chemical)View report Santa BarbaraPFOA (forever chemical)View report Santa ClaraPFOA (forever chemical)View report Santa CruzPFOA (forever chemical)View report Santa Fe I DPFOA (forever chemical)View report Santa Fe SpringsPFOA (forever chemical)View report Santa Margarita DistrictPFOA (forever chemical)View report Santa Margarita District-id9PFOA (forever chemical)View report Santa MariaPFOA (forever chemical)View report Santa MonicaPFOA (forever chemical)View report Santa PaulaPFOA (forever chemical)View report Santa RosaPFOA (forever chemical)View report Sbdno County AreaPFOA (forever chemical)View report Sbdno County Area 70jPFOA (forever chemical)View report Scotts Valley DistrictPFOA (forever chemical)View report Scwa - Arden Park VistaPFOA (forever chemical)View report Scwa - Laguna/vineyardPFOA (forever chemical)View report Scwa Mather-sunrisePFOA (forever chemical)View report Seal BeachPFOA (forever chemical)View report Sfpuc City DistributionPFOA (forever chemical)View report ShafterPFOA (forever chemical)View report Shasta LakePFOA (forever chemical)View report Sierra MadrePFOA (forever chemical)View report Signal HillPFOA (forever chemical)View report SoledadPFOA (forever chemical)View report SonomaPFOA (forever chemical)View report Soquel Creek DistrictPFOA (forever chemical)View report South Coast DistrictPFOA (forever chemical)View report South Feather W P - Miners RanchPFOA (forever chemical)View report South GatePFOA (forever chemical)View report South Montebello Irrigation DistPFOA (forever chemical)View report South PasadenaPFOA (forever chemical)View report South Tahoe Pud -PFOA (forever chemical)View report StocktonPFOA (forever chemical)View report Suisun-solanoPFOA (forever chemical)View report SunnyvalePFOA (forever chemical)View report SweetPFOA (forever chemical)View report Tejon Castac Wd - I5 Laval RdPFOA (forever chemical)View report Temescal Valley DistrictPFOA (forever chemical)View report Thermalito DistPFOA (forever chemical)View report Thousand OaksPFOA (forever chemical)View report TorrancePFOA (forever chemical)View report Trabuco Canyon DistrictPFOA (forever chemical)View report TracyPFOA (forever chemical)View report Truckee-donner PudPFOA (forever chemical)View report Tud - Sonora/jamestownPFOA (forever chemical)View report Tud - Upper BasinPFOA (forever chemical)View report TularePFOA (forever chemical)View report TurlockPFOA (forever chemical)View report TustinPFOA (forever chemical)View report Twentynine Palms DistrictPFOA (forever chemical)View report UkiahPFOA (forever chemical)View report UplandPFOA (forever chemical)View report VacavillePFOA (forever chemical)View report Vallecitos WdPFOA (forever chemical)View report VallejoPFOA (forever chemical)View report Valley Center MwdPFOA (forever chemical)View report Valley County DistPFOA (forever chemical)View report Valley Moon DistrictPFOA (forever chemical)View report VenturaPFOA (forever chemical)View report Ventura Cwwd No 1 - MoorparkPFOA (forever chemical)View report Ventura Wwd No 8 - Simi ValleyPFOA (forever chemical)View report VernonPFOA (forever chemical)View report Victorville DistrictPFOA (forever chemical)View report Vista Irrigation DistrictPFOA (forever chemical)View report Walnut Valley DistrictPFOA (forever chemical)View report WascoPFOA (forever chemical)View report WatsonvillePFOA (forever chemical)View report West Kern DistrictPFOA (forever chemical)View report West SacramentoPFOA (forever chemical)View report West Valley DistrictPFOA (forever chemical)View report Westborough DistrictPFOA (forever chemical)View report Western MwdPFOA (forever chemical)View report Western Mwd - MurrietaPFOA (forever chemical)View report WestminsterPFOA (forever chemical)View report WhittierPFOA (forever chemical)View report WindsorPFOA (forever chemical)View report WoodlandPFOA (forever chemical)View report Yorba Linda DistrictPFOA (forever chemical)View report Yuba CityPFOA (forever chemical)View report Yucaipa Valley DistrictPFOA (forever chemical)View report Largest systems in California
System directory not published for this state
The state report does not yet include an authored population-ordered system list. Use the national directory to search available records.
Browse water systemsWhere the record is thin
Coverage-gap detail not published
This page does not quantify missing or stale records beyond the published indicators above. Treat an absent value as unknown, not as zero.
Read the data methodologyUnderstanding the limits
What this state view does not tell you
A statewide rollup cannot tell you what is delivered to a specific address. Water quality varies by supplier, sampling period and household plumbing. Use a city or water-system report for the evidence behind a local result.
Find the system behind your tapWhat you can do next
Start with your supplier
State patterns cannot identify what reaches a specific address. Resolve your public water system before choosing treatment.
Find the system behind your tapMatch treatment to evidence
A technology is useful only when its certified claim addresses the contaminant and concentration in the local record.
Compare treatment technologiesRead the published contaminant guides
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Filters for what’s on record in California
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How much of California does PurityMap cover?
PurityMap has published records for 342 cities across 341 public water systems in California. Each links back to its dated source record.
What are the most common water concerns in California?
Across published California city records, the contaminants that appear most are Lead (342 cities), Hard water (342 cities), PFOA (forever chemical) (338 cities), PFOS (forever chemical) (338 cities). This reflects what has been monitored and reported, not a ranking of risk.
Sources and methodology
PurityMap assembles this page from the published city and water-system records represented above. Every local report carries its own measurement dates and source documents.
About state sources
How PurityMap analyzes water data