California Drinking Water Compliance Records
2,864 water systems serving 40,236,774 people. 21,013 historical EPA violation records in the Q2 2026 snapshot.
TapScore Compliance-History Grades
A
2,416
84%
B
209
7%
C
131
5%
D
64
2%
F
44
2%
2,864
Water Systems
40,236,774
Population Served
21,013
Historical Records
6,279
Health-Based (All Years)
Systems With the Most Recent EPA Records
CACHEVILLE SERVICE DIST
239 served157 historical records131 recent
D
LINDSAY, CITY OF
12,659 served142 historical records35 recent
F
NORCO, CITY OF
25,068 served54 historical records34 recent
D
OCOTILLO OASIS, LLC
96 served59 historical records33 recent
D
JOHN HOVANNISIAN WATER SYSTEM
80 served50 historical records32 recent
C
VALLEY FORD WATER ASSOCIATION
88 served79 historical records26 recent
F
RAINBIRD VALLEY MWC
238 served61 historical records25 recent
F
FOSTER ROAD MUTUAL WATER COMPANY
150 served27 historical records24 recent
C
RICHGROVE COMMUNITY SERVICES DISTRICT
1,617 served30 historical records24 recent
D
R.S. MUTUAL WATER COMPANY
67 served63 historical records24 recent
F
Large Systems With No Recent Records
LOS ANGELES-CITY, DEPT. OF WATER & POWER
3,875,566 served6 historical records
A
EAST BAY MUD
1,442,800 served4 historical records
A
SAN DIEGO, CITY OF
1,385,379 served6 historical records
A
SAN JOSE WATER
1,039,920 served1 historical record
A
SFPUC CITY DISTRIBUTION DIVISION
848,019 served0 historical records
A
EASTERN MUNICIPAL WD
666,581 served2 historical records
A
CITY OF FRESNO
545,716 served7 historical records
A
CITY OF SACRAMENTO MAIN
527,979 served0 historical records
A
LONG BEACH UTILITIES DEPARTMENT
466,772 served1 historical record
A
IRVINE RANCH WATER DISTRICT
444,800 served4 historical records
A
Largest Water Systems in California
| Water System | Grade | Population | Historical Records |
|---|---|---|---|
| LOS ANGELES-CITY, DEPT. OF WATER & POWER | A | 3,875,566 | 6 |
| EAST BAY MUD | A | 1,442,800 | 4 |
| SAN DIEGO, CITY OF | A | 1,385,379 | 6 |
| SAN JOSE WATER | A | 1,039,920 | 1 |
| SFPUC CITY DISTRIBUTION DIVISION | A | 848,019 | 0 |
| EASTERN MUNICIPAL WD | A | 666,581 | 2 |
| CITY OF FRESNO | A | 545,716 | 7 |
| CITY OF SACRAMENTO MAIN | A | 527,979 | 0 |
| LONG BEACH UTILITIES DEPARTMENT | A | 466,772 | 1 |
| IRVINE RANCH WATER DISTRICT | A | 444,800 | 4 |
| CITY OF ANAHEIM | A | 348,593 | 0 |
| ALAMEDA COUNTY WATER DISTRICT | A | 344,000 | 2 |
| CITY OF SANTA ANA | B | 310,539 | 6 |
| RIVERSIDE, CITY OF | A | 298,398 | 1 |
| SANTA CLARITA VALLEY WATER AGENCY | A | 294,090 | 1 |
| GSWC - SOUTHWEST | A | 277,740 | 4 |
| HELIX WATER DISTRICT | A | 277,668 | 0 |
| COACHELLA VWD: COVE COMMUNITY | A | 270,000 | 2 |
| CWS - BAKERSFIELD | A | 267,881 | 3 |
| SAN GABRIEL VALLEY WATER CO.-EL MONTE | A | 248,000 | 5 |
Contaminants in California
Lead in CaliforniaArsenic in CaliforniaNitrate in CaliforniaFluoride in CaliforniaPFOS in CaliforniaPFOA in CaliforniaTHMs in CaliforniaHAA5 in California
Cities in California
LOS ANGELES(12)SAN JOSE(65)OAKLAND(5)SAN DIEGO(7)SACRAMENTO(68)BURLINGAME(8)ANAHEIM(11)PERRIS(1)FRESNO(42)LONG BEACH(2)IRVINE(8)RIVERSIDE(6)SAN BERNARDINO(13)HAWTHORNE(6)ALHAMBRA(10)FREMONT(4)COVINA(7)DOWNEY(9)SANTA ANA(1)BAKERSFIELD(50)NEWHALL(1)EL MONTE(8)LA MESA(2)PALM DESERT(5)MODESTO(18)SPRING VALLEY(5)FONTANA(1)ROSEMEAD(15)STOCKTON(68)SAN BERNARDIN0(1)OXNARD(13)RANCHO CUCUAMONGA(1)RANCHO SANTA MARGARITA(3)HUNTINGTON BEACH(3)CONCORD(7)PASADENA(4)CHULA VISTA(1)GLENDALE(1)CORTE MADERA(1)SANTA ROSA(39)ONTARIO(3)POMONA(2)JURUPA VALLEY(3)PLEASANTON(4)CORONA(5)GARDEN GROVE(1)ESCONDIDO(6)OCEANSIDE(1)LAGUNA HILLS(4)LAKE ELSINORE(1)HAYWARD(2)RIALTO(2)SUNNYVALE(1)SAN DIMAS(5)ROSEVILLE(5)TEMECULA(3)PLACERVILLE(5)FULLERTON(2)VACAVILLE(13)VICTORVILLE(2)RANCHO CORDOVA(12)SANTA BARBARA(17)VISTA(1)CLOVIS(8)SANTA CLARA(3)PALMDALE(9)ENCINITAS(2)ORANGE(3)VALLEJO(3)AUBURN(10)FAIRFIELD(3)REDDING(17)DAVIS(3)ANTIOCH(1)VENTURA(4)SAN MARCOS(2)COSTA MESA(4)AZUSA(2)SANTA MARIA(7)HIGHLAND(1)SOUTH LAKE TAHOE(5)TORRANCE(1)IMPERIAL BEACH(1)BURBANK(1)DALY CITY(1)WALNUT(1)HESPERIA(2)ELMIRA(1)PACIFIC GROVE(8)TRACY(9)CHINO(2)MERCED(4)SANTA CRUZ(7)SIMI VALLEY(2)CARLSBAD(2)SANTEE(3)MADERA(32)REDWOOD CITY(3)WESTMINSTER(2)SANTA MONICA(1)