Systems with a yearly average above an EPA comparison level
19.3%129 of 670 active community water systems
All 670 systems met the sampling requirement for a yearly average. Of those systems, 129 had at least one yearly average above an EPA comparison level and 541 did not.
EPA-based study benchmark: a fixed, unrounded research cutoff used to reproduce EPA’s final UCMR 5 technical-assistance classification based on the April 2024 federal levels. It is not a current federal or state standard. The label does not determine compliance, household exposure, or health risk.
State rules: The labels on this page use fixed research cutoffs based on the April 2024 federal levels. California may use different current standards or guidance. These UCMR 5 results do not determine current federal or state compliance. Find the official California drinking-water program →
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Find your water system
A ZIP code finds possible public water systems for an area; it cannot identify the supplier for a specific home. Confirm the provider using a water bill or utility record.
Compound summary
System counts in California
Each count shows how many included water systems had a yearly average above the named EPA comparison level.
| EPA rounding cutoff | Systems above comparison level | Water systems included | Percent |
|---|---|---|---|
| PFOA: 4 ppt level; unrounded average ≥4.05 ppt after applying EPA rounding | 84 | 670 | 12.5% |
| PFOS: 4 ppt level; unrounded average ≥4.05 ppt after applying EPA rounding | 114 | 670 | 17.0% |
| PFHxS: 10 ppt level; unrounded average ≥15 ppt after applying EPA rounding | 10 | 670 | 1.5% |
| PFNA: 10 ppt level; unrounded average ≥15 ppt after applying EPA rounding | 0 | 670 | 0.0% |
| HFPO-DA: 10 ppt level; unrounded average ≥15 ppt after applying EPA rounding | 0 | 670 | 0.0% |
| Hazard Index: 1 level; unrounded index ≥1.5 and at least two detected components | 10 | 670 | 1.5% |
System directory
Community water systems with complete monitoring
“Complete monitoring” means at least one sampling location had every required sample needed to calculate a yearly average. It does not mean every location or home was tested. Each PWSID appears once, preventing double counting across ZIP associations.
| Public water system | PWSID | Population served | Primary source | Sampling locations | EPA comparison result |
|---|---|---|---|---|---|
| ADELANTO, CITY OF | CA3610001 | 39,930 | Ground water | 2 | Above an EPA comparison level |
| ALAMEDA COUNTY WATER DISTRICT | CA0110001 | 344,000 | Surface water | 4 | No available average above comparison levels |
| ALCO WATER SERVICE | CA2710001 | 56,253 | Ground water | 6 | No available average above comparison levels |
| AMERICAN VALLEY CSD | CA3210004 | 3,778 | Ground water | 11 | No available average above comparison levels |
| AMERICAN WATER O&M, LLC - VAFB | CA4210700 | 14,971 | Surface water purchased | 2 | No available average above comparison levels |
| ANGELS, CITY OF | CA0510003 | 3,836 | Surface water | 1 | No available average above comparison levels |
| ARCATA, CITY OF | CA1210001 | 20,875 | Ground water purchased | 1 | No available average above comparison levels |
| ARMONA COMMUNITY SERVICES DIST | CA1610001 | 4,143 | Ground water | 1 | No available average above comparison levels |
| ARROWHEAD VILLAS MUTUAL SERVICE COMPANY | CA3610093 | 2,654 | Surface water purchased | 2 | No available average above comparison levels |
| ARROYO GRANDE, WATER DEPARTMENT | CA4010001 | 17,963 | Surface water purchased | 3 | Above an EPA comparison level |
| ARVIN COMMUNITY SERVICES DIST | CA1510001 | 19,669 | Ground water | 3 | No available average above comparison levels |
| ATASCADERO MUTUAL WATER CO | CA4010002 | 30,618 | Ground water | 4 | Above an EPA comparison level |
| ATASCADERO STATE HOSPITAL | CA4010832 | 4,100 | Ground water | 1 | Above an EPA comparison level |
| AVENAL, CITY OF | CA1610002 | 13,696 | Surface water | 2 | No available average above comparison levels |
| AVERYDALE MWC | CA1910023 | 1,023 | Ground water | 2 | No available average above comparison levels |
| AWA BUCKHORN PLANT | CA0310012 | 8,791 | Surface water | 1 | No available average above comparison levels |
| AWA, IONE | CA0310002 | 7,227 | Surface water | 1 | No available average above comparison levels |
| AWA, TANNER | CA0310003 | 4,940 | Surface water | 1 | No available average above comparison levels |
| AZUSA LIGHT AND WATER | CA1910007 | 110,044 | Surface water | 5 | No available average above comparison levels |
| BAKERSFIELD, CITY OF | CA1510031 | 160,144 | Surface water purchased | 43 | Above an EPA comparison level |
| BAKMAN WATER COMPANY | CA1010001 | 17,393 | Ground water | 7 | No available average above comparison levels |
| BAKMAN WATER-ROLLING HILLS | CA2010009 | 1,107 | Ground water | 3 | No available average above comparison levels |
| BANNING, CITY OF | CA3310006 | 31,680 | Ground water | 12 | No available average above comparison levels |
| BAR-LEN MWC | CA3600025 | 126 | Ground water | 1 | No available average above comparison levels |
| BASS LAKE WATER COMPANY | CA2010003 | 4,527 | Surface water | 4 | No available average above comparison levels |
| BEALE AIR FORCE BASE | CA5810700 | 6,785 | Ground water | 1 | No available average above comparison levels |
| BEAR VALLEY CSD | CA1510038 | 5,592 | Ground water | 6 | No available average above comparison levels |
| BEAUMONT CHERRY VALLEY WD | CA3310002 | 66,841 | Ground water | 10 | No available average above comparison levels |
| BELLA VISTA WATER DISTRICT | CA4510014 | 18,612 | Surface water | 6 | No available average above comparison levels |
| BELLFLOWER - SOMERSET MWC | CA1910013 | 46,300 | Surface water purchased | 6 | Above an EPA comparison level |
| BELLFLOWER MUNICIPAL WATER SYSTEM | CA1910018 | 5,999 | Surface water purchased | 2 | Above an EPA comparison level |
| BEVERLY HILLS-CITY, WATER DEPT. | CA1910156 | 40,121 | Surface water purchased | 2 | No available average above comparison levels |
| BIG BEAR CITY CSD | CA3610008 | 12,738 | Ground water | 5 | Above an EPA comparison level |
| BIG BEAR LAKE DWP - BIG BEAR SYSTEM | CA3610044 | 26,132 | Ground water | 22 | No available average above comparison levels |
| BISHOP, CITY OF | CA1410001 | 3,819 | Ground water | 2 | No available average above comparison levels |
| BLUE LAKE SPRINGS MUT WTR | CA0510009 | 4,841 | Surface water purchased | 2 | No available average above comparison levels |
| BLUE LAKE, CITY OF | CA1210002 | 1,172 | Ground water purchased | 1 | No available average above comparison levels |
| BLYTHE - CITY OF | CA3310003 | 9,798 | Ground water | 3 | No available average above comparison levels |
| BOLINAS COMMUNITY PUD | CA2110005 | 2,483 | Surface water | 1 | No available average above comparison levels |
| BORREGO WD | CA3710036 | 3,429 | Ground water | 9 | No available average above comparison levels |
| BRAWLEY, CITY OF | CA1310001 | 26,862 | Surface water purchased | 1 | No available average above comparison levels |
| BRENTWOOD | CA0710004 | 64,513 | Surface water purchased | 6 | No available average above comparison levels |
| BROOKTRAILS TOWNSHIP CSD | CA2310009 | 3,632 | Surface water | 1 | No available average above comparison levels |
| BUELLTON WATER DEPARTMENT | CA4210018 | 5,161 | Surface water purchased | 3 | No available average above comparison levels |
| BURBANK-CITY, WATER DEPT. | CA1910179 | 105,603 | Surface water purchased | 1 | No available average above comparison levels |
| CAL AM - MEADOWBROOK | CA2410008 | 5,656 | Ground water | 3 | Above an EPA comparison level |
| CAL AM - OAKHURST | CA2010007 | 3,693 | Ground water | 4 | No available average above comparison levels |
| CAL AM WATER COMPANY - MONTEREY | CA2710004 | 92,450 | Groundwater under influence of surface water | 12 | Above an EPA comparison level |
| CAL AMERICAN WATER CO | CA5610040 | 66,809 | Surface water purchased | 1 | No available average above comparison levels |
| CAL-AM WATER COMPANY - DUARTE | CA1910186 | 24,773 | Ground water | 8 | No available average above comparison levels |
| CAL-WATER SERVICE CO.-CHICO | CA0410002 | 114,925 | Ground water | 37 | Above an EPA comparison level |
| CAL-WATER SERVICE CO.-MARYSVILLE | CA5810001 | 12,419 | Ground water | 8 | No available average above comparison levels |
| CAL-WATER SERVICE CO.-OROVILLE | CA0410005 | 11,106 | Surface water | 2 | No available average above comparison levels |
| CAL-WATER SERVICE CO.-WILLOWS | CA1110003 | 7,240 | Ground water | 4 | No available average above comparison levels |
| CAL/AM WATER COMPANY - BALDWIN HILLS | CA1910052 | 20,724 | Surface water purchased | 5 | No available average above comparison levels |
| CAL/AM WATER COMPANY - SAN MARINO | CA1910139 | 47,995 | Surface water purchased | 7 | No available average above comparison levels |
| CALAM - ANTELOPE | CA3410031 | 35,534 | Surface water purchased | 15 | No available average above comparison levels |
| CALAM - ARDEN | CA3410045 | 4,191 | Surface water purchased | 6 | Above an EPA comparison level |
| CALAM - LINCOLN OAKS | CA3410013 | 48,094 | Surface water purchased | 20 | No available average above comparison levels |
| CALAM - PARKWAY | CA3410017 | 50,573 | Surface water purchased | 9 | Above an EPA comparison level |
| CALAM - WEST PLACER | CA3110150 | 8,861 | Surface water purchased | 1 | No available average above comparison levels |
| CALAVERAS PUD | CA0510002 | 6,286 | Surface water | 1 | No available average above comparison levels |
| CALEXICO, CITY OF | CA1310002 | 40,357 | Surface water purchased | 1 | No available average above comparison levels |
| CALIFORNIA CITY, CITY OF | CA1510032 | 14,198 | Surface water purchased | 5 | No available average above comparison levels |
| CALIFORNIA INSTITUTION FOR MEN | CA3610850 | 10,667 | Ground water | 1 | No available average above comparison levels |
| CALIFORNIA MENS COLONY | CA4010830 | 15,000 | Surface water | 1 | No available average above comparison levels |
| CALIFORNIA REHABILITATION CENTER - NORCO | CA3310800 | 4,300 | Surface water purchased | 1 | No available average above comparison levels |
| CALIFORNIA STATE FAIR | CA3410026 | 9,280 | Ground water | 4 | Above an EPA comparison level |
| CALIFORNIA STATE PRISON - SOLANO | CA4810800 | 5,100 | Surface water | 2 | No available average above comparison levels |
| CALIFORNIA STATE UNIVERSITY FRESNO | CA1010339 | 41,000 | Ground water | 3 | Above an EPA comparison level |
| CALIFORNIA WATER SERVICE - BEAR GULCH | CA4110006 | 61,431 | Surface water | 1 | No available average above comparison levels |
| CALIFORNIA WATER SERVICE - LIVERMORE | CA0110003 | 60,414 | Surface water purchased | 8 | Above an EPA comparison level |
| CALIFORNIA WATER SERVICE - SAN CARLOS | CA4110007 | 35,344 | Surface water purchased | 1 | No available average above comparison levels |
| CALIFORNIA WATER SERVICE - SAN MATEO | CA4110008 | 102,348 | Surface water purchased | 1 | No available average above comparison levels |
| CALIFORNIA WATER SERVICE - STOCKTON | CA3910001 | 176,266 | Surface water purchased | 12 | No available average above comparison levels |
| CALIFORNIA WATER SERVICE CO - WESTLAKE | CA5610016 | 19,533 | Surface water purchased | 1 | No available average above comparison levels |
| CALIFORNIA WATER SERVICE CO. - DIXON | CA4810002 | 10,623 | Ground water | 3 | No available average above comparison levels |
| CALIFORNIA WATER SERVICE CO. - DOMINGUEZ | CA1910033 | 143,996 | Surface water purchased | 9 | No available average above comparison levels |
| CALIFORNIA WATER SERVICE CO. - ELA | CA1910036 | 152,474 | Surface water purchased | 10 | Above an EPA comparison level |
| CALIFORNIA WATER SERVICE CO. - HERM/REDO | CA1910134 | 96,853 | Surface water purchased | 3 | No available average above comparison levels |
| CALIFORNIA WATER SERVICE CO. - PALOS VER | CA1910104 | 71,452 | Surface water purchased | 1 | No available average above comparison levels |
| CALIFORNIA WATER SERVICE CO.-LANCASTER | CA1910010 | 1,387 | Surface water purchased | 2 | No available average above comparison levels |
| CALIFORNIA WATER SERVICE CO.-TRAVIS AFB | CA4810701 | 18,111 | Surface water purchased | 1 | No available average above comparison levels |
| CALIFORNIA WATER SERVICE-S SAN FRANCISCO | CA4110009 | 64,146 | Surface water purchased | 2 | No available average above comparison levels |
| CALIFORNIA-AMERICAN GEYSERVILLE (PUC) | CA4910024 | 1,046 | Ground water | 2 | No available average above comparison levels |
| CALIFORNIA-AMERICAN LARKFIELD (PUC) | CA4910023 | 7,913 | Ground water | 2 | No available average above comparison levels |
| CALIPATRIA STATE PRISON | CA1310800 | 4,800 | Surface water purchased | 1 | No available average above comparison levels |
| CALISTOGA, CITY OF | CA2810002 | 5,610 | Surface water | 2 | No available average above comparison levels |
| CAMARILLO WATER DEPT | CA5610019 | 46,824 | Surface water purchased | 4 | No available average above comparison levels |
| CAMBRIA COMM SERVICES DIST | CA4010014 | 5,532 | Ground water | 1 | No available average above comparison levels |
| CAMP PENDLETON (NORTH) | CA3710700 | 12,651 | Ground water | 1 | No available average above comparison levels |
| CAMP PENDLETON (SOUTH) | CA3710702 | 42,219 | Ground water | 2 | No available average above comparison levels |
| CAMROSA WATER DISTRICT | CA5610063 | 32,700 | Surface water purchased | 5 | Above an EPA comparison level |
| CANADA WOODS WC | CA2702588 | 356 | Groundwater under influence of surface water | 1 | No available average above comparison levels |
| CARLSBAD MWD | CA3710005 | 95,158 | Surface water purchased | 4 | No available average above comparison levels |
| CARMICHAEL WATER DISTRICT | CA3410004 | 41,193 | Groundwater under influence of surface water | 6 | No available average above comparison levels |
| CARPINTERIA VALLEY WATER DISTRICT | CA4210001 | 15,996 | Surface water purchased | 4 | No available average above comparison levels |
| CASITAS MUNICIPAL WATER DIST | CA5610024 | 11,005 | Surface water | 2 | No available average above comparison levels |
| CASTROVILLE COMMUNITY SERVICES DISTRICT | CA2710005 | 7,515 | Ground water | 2 | No available average above comparison levels |
| CCI - TEHACHAPI | CA1510800 | 2,993 | Ground water | 1 | No available average above comparison levels |
| CCWD - COPPER COVE | CA0510017 | 5,187 | Surface water | 1 | No available average above comparison levels |
| CCWD - JENNY LIND | CA0510006 | 9,861 | Surface water | 1 | No available average above comparison levels |
| CDCR-HIGH DESERT STATE PRISON | CA1805004 | 3,857 | Ground water | 2 | No available average above comparison levels |
| CENTERVILLE C.S.D. | CA4510011 | 4,151 | Surface water purchased | 1 | No available average above comparison levels |
| CENTINELA STATE PRISON | CA1310801 | 4,100 | Surface water purchased | 1 | No available average above comparison levels |
| CERES, CITY OF | CA5010028 | 54,513 | Surface water purchased | 8 | Above an EPA comparison level |
| CERRITOS - CITY, WATER DEPT. | CA1910019 | 47,475 | Surface water purchased | 4 | No available average above comparison levels |
| CHANNEL ISLANDS BEACH CSD | CA5610039 | 4,560 | Surface water purchased | 1 | No available average above comparison levels |
| CHINA LAKE NAVAL AIR WEAPONS STATION | CA1510703 | 6,600 | Ground water | 6 | No available average above comparison levels |
| CHINO HILLS, CITY OF | CA3610036 | 76,414 | Surface water purchased | 2 | No available average above comparison levels |
| CHINO, CITY OF | CA3610012 | 86,435 | Surface water purchased | 8 | No available average above comparison levels |
| CHOWCHILLA CITY WATER DEPT | CA2010001 | 13,916 | Ground water | 6 | No available average above comparison levels |
| CHUCKAWALLA VALLEY STATE PRISON | CA3310802 | 4,090 | Ground water | 1 | No available average above comparison levels |
| CITRUS HEIGHTS WATER DISTRICT | CA3410006 | 67,818 | Surface water purchased | 5 | No available average above comparison levels |
| CITY OF ALHAMBRA | CA1910001 | 79,776 | Surface water purchased | 4 | No available average above comparison levels |
| CITY OF ALTURAS | CA2510001 | 2,715 | Ground water | 4 | No available average above comparison levels |
| CITY OF ANAHEIM | CA3010001 | 348,593 | Surface water | 17 | Above an EPA comparison level |
| CITY OF ANTIOCH | CA0710001 | 115,074 | Surface water | 1 | No available average above comparison levels |
| CITY OF ARCADIA | CA1910003 | 51,361 | Ground water | 9 | Above an EPA comparison level |
| CITY OF ATWATER | CA2410001 | 29,479 | Ground water | 8 | Above an EPA comparison level |
| CITY OF BELL GARDENS | CA1910108 | 11,437 | Surface water purchased | 2 | Above an EPA comparison level |
| CITY OF BENICIA | CA4810001 | 27,131 | Surface water | 1 | No available average above comparison levels |
| CITY OF BREA | CA3010002 | 48,479 | Surface water purchased | 3 | No available average above comparison levels |
| CITY OF BUENA PARK | CA3010003 | 81,998 | Surface water purchased | 9 | Above an EPA comparison level |
| CITY OF CLOVIS | CA1010003 | 130,130 | Surface water | 38 | Above an EPA comparison level |
| CITY OF COLUSA | CA0610002 | 6,447 | Ground water | 5 | No available average above comparison levels |
| CITY OF CORNING | CA5210001 | 8,244 | Ground water | 7 | No available average above comparison levels |
| CITY OF CRESCENT CITY | CA0810001 | 17,262 | Ground water | 1 | No available average above comparison levels |
| CITY OF CUPERTINO | CA4310018 | 16,336 | Surface water purchased | 2 | No available average above comparison levels |
| CITY OF DALY CITY | CA4110013 | 104,901 | Surface water purchased | 5 | No available average above comparison levels |
| CITY OF DAVIS | CA5710001 | 67,457 | Surface water purchased | 8 | No available average above comparison levels |
| CITY OF DIXON | CA4810009 | 12,540 | Ground water | 4 | No available average above comparison levels |
| CITY OF DOS PALOS | CA2410002 | 7,452 | Surface water | 1 | No available average above comparison levels |
| CITY OF FAIRFIELD | CA4810003 | 120,377 | Surface water | 2 | No available average above comparison levels |
| CITY OF FOUNTAIN VALLEY | CA3010069 | 56,747 | Surface water purchased | 7 | No available average above comparison levels |
| CITY OF FOWLER | CA1010006 | 7,448 | Ground water | 6 | No available average above comparison levels |
| CITY OF FRESNO | CA1010007 | 545,716 | Surface water | 174 | Above an EPA comparison level |
| CITY OF FULLERTON | CA3010010 | 139,461 | Surface water purchased | 7 | Above an EPA comparison level |
| CITY OF GARDEN GROVE | CA3010062 | 174,226 | Surface water purchased | 11 | Above an EPA comparison level |
| CITY OF GILROY | CA4310004 | 59,203 | Ground water | 7 | Above an EPA comparison level |
| CITY OF GRASS VALLEY | CA2910001 | 4,947 | Surface water | 1 | No available average above comparison levels |
| CITY OF GRIDLEY | CA0410004 | 7,269 | Ground water | 5 | Above an EPA comparison level |
| CITY OF GUSTINE | CA2410003 | 6,110 | Ground water | 4 | No available average above comparison levels |
| CITY OF HAYWARD | CA0110006 | 162,954 | Surface water purchased | 2 | No available average above comparison levels |
| CITY OF HUNTINGTON BEACH | CA3010053 | 201,000 | Surface water purchased | 10 | Above an EPA comparison level |
| CITY OF INDUSTRY WATERWORKS SYSTEMS | CA1910029 | 6,158 | Ground water | 1 | No available average above comparison levels |
| CITY OF JACKSON | CA0310001 | 5,019 | Surface water purchased | 1 | No available average above comparison levels |
| CITY OF LA HABRA | CA3010018 | 63,118 | Surface water purchased | 3 | No available average above comparison levels |
| CITY OF LA PALMA | CA3010100 | 15,948 | Surface water purchased | 3 | No available average above comparison levels |
| CITY OF LATHROP | CA3910015 | 35,080 | Surface water purchased | 2 | Above an EPA comparison level |
| CITY OF LINCOLN | CA3110004 | 54,538 | Surface water purchased | 3 | No available average above comparison levels |
| CITY OF LIVE OAK, CA | CA5110001 | 9,285 | Ground water | 4 | No available average above comparison levels |
| CITY OF LIVERMORE | CA0110011 | 38,892 | Surface water purchased | 1 | No available average above comparison levels |
| CITY OF LIVINGSTON | CA2410004 | 14,894 | Ground water | 8 | No available average above comparison levels |
| CITY OF LOS BANOS | CA2410005 | 47,419 | Ground water | 13 | No available average above comparison levels |
| CITY OF MADERA | CA2010002 | 66,560 | Ground water | 9 | No available average above comparison levels |
| CITY OF MARTINEZ | CA0710006 | 30,997 | Surface water purchased | 1 | No available average above comparison levels |
| CITY OF MERCED | CA2410009 | 93,692 | Ground water | 21 | Above an EPA comparison level |
| CITY OF MILLBRAE | CA4110018 | 22,795 | Surface water purchased | 1 | No available average above comparison levels |
| CITY OF MILPITAS | CA4310005 | 81,773 | Surface water purchased | 2 | No available average above comparison levels |
| CITY OF MODESTO - SALIDA | CA5010005 | 14,537 | Surface water purchased | 2 | No available average above comparison levels |
| CITY OF MORGAN HILL | CA4310006 | 47,374 | Ground water | 16 | No available average above comparison levels |
| CITY OF MOUNTAIN VIEW | CA4310007 | 81,501 | Surface water purchased | 6 | No available average above comparison levels |
| CITY OF NEWMAN-WATER DEPARTMENT | CA5010013 | 12,207 | Ground water | 5 | No available average above comparison levels |
| CITY OF NEWPORT BEACH | CA3010023 | 68,572 | Surface water purchased | 2 | No available average above comparison levels |
| CITY OF ORANGE | CA3010027 | 120,770 | Surface water purchased | 11 | Above an EPA comparison level |
| CITY OF ORANGE COVE | CA1010023 | 9,525 | Surface water | 1 | No available average above comparison levels |
| CITY OF ORLAND | CA1110001 | 8,298 | Ground water | 7 | No available average above comparison levels |
| CITY OF PALO ALTO | CA4310009 | 67,231 | Surface water purchased | 1 | No available average above comparison levels |
| CITY OF PARLIER | CA1010025 | 14,576 | Ground water | 4 | No available average above comparison levels |
| CITY OF PITTSBURG | CA0710008 | 62,500 | Surface water purchased | 1 | No available average above comparison levels |
| CITY OF PLEASANTON | CA0110008 | 76,689 | Surface water purchased | 3 | Above an EPA comparison level |
| CITY OF RED BLUFF | CA5210004 | 14,710 | Ground water | 11 | No available average above comparison levels |
| CITY OF REDDING | CA4510005 | 89,628 | Surface water | 11 | Above an EPA comparison level |
| CITY OF RIO VISTA | CA4810004 | 10,489 | Ground water | 7 | No available average above comparison levels |
| CITY OF ROSEVILLE | CA3110008 | 155,612 | Surface water | 8 | No available average above comparison levels |
| CITY OF SACRAMENTO MAIN | CA3410020 | 527,979 | Surface water | 13 | Above an EPA comparison level |
| CITY OF SAN BRUNO | CA4110023 | 42,631 | Surface water purchased | 5 | No available average above comparison levels |
| CITY OF SAN CLEMENTE | CA3010036 | 51,545 | Surface water purchased | 2 | No available average above comparison levels |
| CITY OF SAN JOSE - EVG/EDV/COY | CA4310020 | 101,265 | Surface water purchased | 4 | No available average above comparison levels |
| CITY OF SAN JOSE - NSJ/ALVISO | CA4310019 | 45,559 | Surface water purchased | 3 | No available average above comparison levels |
| CITY OF SAN JUAN CAPISTRANO | CA3010030 | 39,684 | Surface water purchased | 3 | No available average above comparison levels |
| CITY OF SANGER | CA1010029 | 26,357 | Ground water | 10 | Above an EPA comparison level |
| CITY OF SANTA ANA | CA3010038 | 310,539 | Surface water purchased | 12 | Above an EPA comparison level |
| CITY OF SANTA BARBARA WATER DEPARTMENT | CA4210010 | 99,323 | Surface water | 2 | No available average above comparison levels |
| CITY OF SANTA CLARA | CA4310012 | 130,746 | Surface water purchased | 20 | No available average above comparison levels |
| CITY OF SEAL BEACH | CA3010041 | 24,937 | Surface water purchased | 4 | No available average above comparison levels |
| CITY OF SHASTA LAKE | CA4510006 | 10,657 | Surface water | 1 | No available average above comparison levels |
| CITY OF SOUTH PASADENA | CA1910154 | 25,329 | Surface water purchased | 2 | No available average above comparison levels |
| CITY OF STOCKTON | CA3910012 | 191,302 | Surface water | 17 | Above an EPA comparison level |
| CITY OF SUNNYVALE | CA4310014 | 157,566 | Surface water purchased | 8 | No available average above comparison levels |
| CITY OF SUSANVILLE | CA1810001 | 7,811 | Ground water | 5 | No available average above comparison levels |
| CITY OF TUSTIN | CA3010046 | 66,600 | Surface water purchased | 5 | No available average above comparison levels |
| CITY OF VACAVILLE | CA4810008 | 99,650 | Surface water | 9 | Above an EPA comparison level |
| CITY OF VALLEJO | CA4810007 | 121,420 | Surface water | 1 | No available average above comparison levels |
| CITY OF VALLEJO-LAKES SYSTEM | CA4810021 | 2,800 | Surface water | 1 | No available average above comparison levels |
| CITY OF WATERFORD | CA5010006 | 8,788 | Ground water | 4 | No available average above comparison levels |
| CITY OF WESTMINSTER | CA3010064 | 90,911 | Surface water purchased | 10 | Above an EPA comparison level |
| CITY OF WHEATLAND | CA5810004 | 4,124 | Ground water | 6 | Above an EPA comparison level |
| CITY OF WILLIAMS | CA0610004 | 5,538 | Ground water | 2 | No available average above comparison levels |
| CITY OF WINTERS | CA5710005 | 7,115 | Ground water | 5 | No available average above comparison levels |
| CITY OF WOODLAND | CA5710006 | 61,462 | Surface water purchased | 8 | No available average above comparison levels |
| CITY OF YUBA CITY | CA5110002 | 70,256 | Surface water | 1 | No available average above comparison levels |
| CLEAR CREEK CSD-ANDERSON | CA4510016 | 8,900 | Surface water | 4 | No available average above comparison levels |
| CLOVERDALE, CITY OF | CA4910002 | 10,398 | Groundwater under influence of surface water | 1 | No available average above comparison levels |
| COACHELLA VWD: COVE COMMUNITY | CA3310001 | 270,000 | Ground water | 20 | No available average above comparison levels |
| COACHELLA VWD: I.D. NO. 8 | CA3310048 | 4,600 | Ground water | 4 | No available average above comparison levels |
| COACHELLA WATER AUTHORITY | CA3310007 | 43,590 | Ground water | 6 | No available average above comparison levels |
| COALINGA-CITY | CA1010004 | 17,277 | Surface water | 1 | No available average above comparison levels |
| COASTSIDE COUNTY WATER DISTRICT | CA4110011 | 18,940 | Surface water | 2 | No available average above comparison levels |
| COLTON, CITY OF | CA3610014 | 46,525 | Ground water | 8 | Above an EPA comparison level |
| COMMERCE-CITY, WATER DEPT. | CA1910050 | 4,205 | Surface water purchased | 3 | Above an EPA comparison level |
| COMPTON-CITY, WATER DEPT. | CA1910026 | 74,877 | Surface water purchased | 6 | Above an EPA comparison level |
| CONTRA COSTA WATER DISTRICT | CA0710003 | 198,000 | Surface water | 3 | No available average above comparison levels |
| CORCORAN, CITY OF | CA1610004 | 22,808 | Ground water | 1 | No available average above comparison levels |
| CORONA, CITY OF | CA3310037 | 168,575 | Surface water purchased | 15 | No available average above comparison levels |
| CORRECTIONAL TRAINING FACILITY - SOLEDAD | CA2710850 | 4,269 | Ground water | 1 | No available average above comparison levels |
| COTATI, CITY OF | CA4910016 | 7,303 | Ground water | 5 | No available average above comparison levels |
| COTTONWOOD COUNTY WATER DIST. | CA4510007 | 3,316 | Ground water | 5 | No available average above comparison levels |
| COVINA-CITY, WATER DEPT. | CA1910127 | 33,300 | Surface water purchased | 3 | No available average above comparison levels |
| CRESCENTA VALLEY CWD | CA1910028 | 35,841 | Surface water purchased | 7 | Above an EPA comparison level |
| CRESTLINE VILLAGE CWD - DIVISION 10 | CA3610015 | 11,650 | Surface water purchased | 16 | Above an EPA comparison level |
| CSA 70 W-3 HACIENDA | CA3600114 | 611 | Ground water | 2 | No available average above comparison levels |
| CUCAMONGA VALLEY WATER DISTRICT | CA3610018 | 211,069 | Surface water | 8 | No available average above comparison levels |
| CUTLER PUD | CA5410001 | 6,200 | Ground water | 2 | No available average above comparison levels |
| CWS - BAKERSFIELD | CA1510003 | 267,881 | Surface water | 47 | Above an EPA comparison level |
| CWS - NORTH GARDEN | CA1510055 | 22,762 | Surface water | 9 | Above an EPA comparison level |
| CWS - SELMA | CA1010024 | 26,517 | Ground water | 8 | No available average above comparison levels |
| CWS - VISALIA | CA5410016 | 148,496 | Ground water | 43 | Above an EPA comparison level |
| CWSC KING CITY | CA2710009 | 16,334 | Ground water | 6 | No available average above comparison levels |
| CWSC LAS LOMAS | CA2710013 | 2,084 | Ground water | 2 | No available average above comparison levels |
| CWSC LOS ALTOS SUBURBAN | CA4310001 | 69,973 | Surface water purchased | 16 | No available average above comparison levels |
| CWSC OAK HILLS | CA2710019 | 3,161 | Ground water | 2 | No available average above comparison levels |
| CWSC SALINAS | CA2710010 | 123,679 | Ground water | 20 | No available average above comparison levels |
| CWSC SALINAS HILLS | CA2710012 | 5,293 | Ground water | 6 | No available average above comparison levels |
| Cache Creek Casino Resort | 090605107 | 12,800 | Ground water | 2 | No available average above comparison levels |
| Cal Am - Fruitridge Vista | CA3410023 | 15,652 | Surface water purchased | 9 | No available average above comparison levels |
| Cal Am - Suburban Rosemont | CA3410010 | 54,793 | Surface water purchased | 20 | Above an EPA comparison level |
| California Village | 090600237 | 1,290 | Ground water purchased | 1 | No available average above comparison levels |
| Colusa Southern System | 090605047 | 3,474 | Ground water | 2 | No available average above comparison levels |
| DEL MAR, CITY OF | CA3710004 | 3,919 | Surface water purchased | 1 | No available average above comparison levels |
| DEL PASO MANOR COUNTY WATER DI | CA3410007 | 4,854 | Ground water | 4 | No available average above comparison levels |
| DELANO, CITY OF | CA1510005 | 51,428 | Ground water | 12 | No available average above comparison levels |
| DELHI CWD | CA2410006 | 7,784 | Ground water | 4 | No available average above comparison levels |
| DENAIR COMMUNITY SERVICES DISTRICT | CA5010021 | 5,090 | Ground water | 4 | No available average above comparison levels |
| DESERT WATER AGENCY | CA3310005 | 74,807 | Surface water | 9 | No available average above comparison levels |
| DINUBA, CITY OF | CA5410002 | 27,281 | Ground water | 7 | No available average above comparison levels |
| DOWNEY - CITY, WATER DEPT. | CA1910034 | 110,556 | Ground water | 5 | Above an EPA comparison level |
| DUBLIN SAN RAMON SERVICES DISTRICT | CA0110009 | 98,776 | Surface water purchased | 1 | No available average above comparison levels |
| EARLIMART PUD | CA5410021 | 7,679 | Ground water | 4 | No available average above comparison levels |
| EAST BAY MUD | CA0110005 | 1,442,800 | Surface water | 6 | No available average above comparison levels |
| EAST NILES CSD | CA1510006 | 32,517 | Surface water purchased | 3 | No available average above comparison levels |
| EAST PASADENA WATER CO. | CA1910020 | 9,949 | Ground water | 2 | No available average above comparison levels |
| EAST VALLEY WATER DISTRICT | CA3610064 | 108,629 | Surface water | 13 | Above an EPA comparison level |
| EASTERN MUNICIPAL WD | CA3310009 | 666,581 | Surface water purchased | 14 | No available average above comparison levels |
| EDWARDS AFB - MAIN BASE | CA1510701 | 11,316 | Surface water purchased | 2 | No available average above comparison levels |
| EL DORADO ID - MAIN | CA0910001 | 132,171 | Surface water | 3 | No available average above comparison levels |
| EL MONTE-CITY, WATER DEPT. | CA1910038 | 22,968 | Ground water | 4 | No available average above comparison levels |
| EL TORO WATER DISTRICT | CA3010079 | 51,800 | Surface water purchased | 4 | No available average above comparison levels |
| ELK GROVE WATER SERVICE | CA3410008 | 43,813 | Surface water purchased | 5 | No available average above comparison levels |
| ELSINORE VALLEY MWD | CA3310012 | 169,455 | Surface water | 8 | No available average above comparison levels |
| ESCALON, CITY OF | CA3910003 | 7,429 | Ground water | 3 | No available average above comparison levels |
| ESTERO MUNICIPAL IMPROVEMENT DISTRICT | CA4110021 | 36,556 | Surface water purchased | 1 | No available average above comparison levels |
| EUREKA, CITY OF | CA1210004 | 27,078 | Ground water purchased | 1 | No available average above comparison levels |
| FAIR OAKS WATER DISTRICT | CA3410009 | 36,226 | Surface water purchased | 5 | No available average above comparison levels |
| FALLBROOK PUD | CA3710008 | 35,237 | Surface water purchased | 3 | No available average above comparison levels |
| FARM MUTUAL W.C. (THE) | CA3310046 | 4,026 | Surface water purchased | 1 | No available average above comparison levels |
| FARMERSVILLE, CITY OF | CA5410004 | 10,243 | Ground water | 4 | No available average above comparison levels |
| FILLMORE WATER DEPT | CA5610002 | 16,419 | Ground water | 2 | No available average above comparison levels |
| FIREBAUGH CITY | CA1010005 | 8,096 | Ground water | 2 | No available average above comparison levels |
| FLORIN COUNTY WATER DISTRICT | CA3410033 | 7,831 | Ground water | 10 | Above an EPA comparison level |
| FOLSOM STATE PRISON | CA3410032 | 7,502 | Surface water | 1 | No available average above comparison levels |
| FOLSOM, CITY OF - ASHLAND | CA3410030 | 3,317 | Surface water purchased | 1 | No available average above comparison levels |
| FOLSOM, CITY OF - MAIN | CA3410014 | 80,969 | Surface water | 1 | No available average above comparison levels |
| FORESTHILL PUBLIC UTILITY DIST | CA3110003 | 6,782 | Surface water | 1 | No available average above comparison levels |
| FORT BRAGG, CITY OF | CA2310001 | 6,919 | Surface water | 1 | No available average above comparison levels |
| FORTUNA, CITY OF | CA1210006 | 12,133 | Ground water | 1 | No available average above comparison levels |
| GALT, CITY OF | CA3410011 | 26,536 | Ground water | 3 | No available average above comparison levels |
| GEORGETOWN DIVIDE PUD | CA0910013 | 9,434 | Surface water | 2 | No available average above comparison levels |
| GLEN HELEN WATER SYSTEM | CA3600108 | 5,900 | Ground water | 5 | No available average above comparison levels |
| GLENDALE-CITY, WATER DEPT. | CA1910043 | 188,784 | Surface water purchased | 5 | Above an EPA comparison level |
| GLENDORA-CITY, WATER DEPT. | CA1910044 | 49,934 | Surface water purchased | 3 | No available average above comparison levels |
| GOLDEN HILLS CSD | CA1510045 | 9,857 | Ground water | 8 | Above an EPA comparison level |
| GOLDEN STATE WATER CO - APPLE VLY SOUTH | CA3610107 | 6,208 | Ground water | 3 | No available average above comparison levels |
| GOLDEN STATE WATER CO - ARDEN WATER SERV | CA3410003 | 5,658 | Ground water | 6 | No available average above comparison levels |
| GOLDEN STATE WATER CO - BARSTOW | CA3610043 | 32,547 | Ground water | 4 | No available average above comparison levels |
| GOLDEN STATE WATER CO - WRIGHTWOOD | CA3610047 | 4,177 | Ground water | 8 | No available average above comparison levels |
| GOLDEN STATE WATER CO. - CORDOVA | CA3410015 | 47,161 | Surface water | 8 | No available average above comparison levels |
| GOLDEN STATE WATER CO.-CLEARLAKE SYSTEM | CA1710002 | 4,644 | Surface water | 1 | No available average above comparison levels |
| GOLDEN STATE WATER COMPANY - BAY POINT | CA0710002 | 23,731 | Surface water purchased | 1 | No available average above comparison levels |
| GOLDEN STATE WATER COMPANY - LOS OSOS | CA4010017 | 5,924 | Ground water | 4 | No available average above comparison levels |
| GOLDEN STATE WATER COMPANY - NIPOMO | CA4010018 | 4,506 | Surface water purchased | 3 | No available average above comparison levels |
| GOLDEN STATE WATER COMPANY - SIMI VALLEY | CA5610059 | 45,128 | Surface water purchased | 2 | No available average above comparison levels |
| GOLDEN STATE WC - COWAN HEIGHTS | CA3010047 | 6,997 | Surface water purchased | 2 | No available average above comparison levels |
| GOLDEN STATE WC - PLACENTIA/YORBA LINDA | CA3010035 | 50,381 | Surface water purchased | 4 | Above an EPA comparison level |
| GOLDEN STATE WC - WEST ORANGE COUNTY | CA3010022 | 114,379 | Surface water purchased | 12 | Above an EPA comparison level |
| GOLETA WATER DISTRICT | CA4210004 | 84,462 | Surface water | 10 | No available average above comparison levels |
| GONZALES, CITY OF | CA2710007 | 8,327 | Ground water | 4 | No available average above comparison levels |
| GREAT OAKS WC INC | CA4310022 | 110,088 | Ground water | 19 | No available average above comparison levels |
| GREENFIELD COUNTY WD | CA1510024 | 11,590 | Ground water | 6 | No available average above comparison levels |
| GREENFIELD, CITY OF | CA2710008 | 18,967 | Ground water | 2 | No available average above comparison levels |
| GROVELAND COMMUNITY SERV DIST | CA5510009 | 3,400 | Surface water | 3 | No available average above comparison levels |
| GROVER BEACH WATER DEPARTMENT | CA4010004 | 12,701 | Surface water | 2 | No available average above comparison levels |
| GSWC - ARTESIA | CA1910004 | 50,415 | Ground water | 5 | Above an EPA comparison level |
| GSWC - BELL, BELL GARDENS | CA1910011 | 55,050 | Surface water purchased | 5 | Above an EPA comparison level |
| GSWC - CLAREMONT | CA1910024 | 39,730 | Surface water purchased | 11 | Above an EPA comparison level |
| GSWC - CULVER CITY | CA1910030 | 38,233 | Surface water purchased | 1 | No available average above comparison levels |
| GSWC - FLORENCE/GRAHAM | CA1910077 | 63,472 | Surface water purchased | 3 | No available average above comparison levels |
| GSWC - HOLLYDALE | CA1910195 | 8,099 | Ground water | 2 | No available average above comparison levels |
| GSWC - NORWALK | CA1910098 | 43,167 | Surface water purchased | 6 | No available average above comparison levels |
| GSWC - SOUTHWEST | CA1910155 | 277,740 | Surface water purchased | 8 | No available average above comparison levels |
| GSWC - Willowbrook | CA1910072 | 10,793 | Surface water purchased | 2 | No available average above comparison levels |
| GSWC-CALIPATRIA | CA1310003 | 7,363 | Surface water purchased | 1 | No available average above comparison levels |
| GSWC-SAN DIMAS | CA1910142 | 56,538 | Surface water purchased | 6 | Above an EPA comparison level |
| GSWC-SOUTH ARCADIA | CA1910212 | 27,072 | Ground water | 5 | Above an EPA comparison level |
| GSWC-SOUTH SAN GABRIEL | CA1910223 | 26,240 | Surface water purchased | 3 | No available average above comparison levels |
| GUADALUPE VALLEY MID | CA4110005 | 1,472 | Surface water purchased | 1 | No available average above comparison levels |
| GUADALUPE WATER DEPARTMENT | CA4210003 | 8,897 | Surface water purchased | 1 | No available average above comparison levels |
| Golden State Water Co. - Orcutt | CA4210016 | 34,102 | Surface water purchased | 12 | No available average above comparison levels |
| HANFORD, CITY OF | CA1610003 | 62,127 | Ground water | 13 | No available average above comparison levels |
| HAWTHORNE-CITY WATER DEPT. | CA1910047 | 44,718 | Surface water purchased | 2 | No available average above comparison levels |
| HEALDSBURG, CITY OF | CA4910005 | 10,985 | Groundwater under influence of surface water | 3 | No available average above comparison levels |
| HEBER PUBLIC UTILITY DISTRICT | CA1310007 | 6,979 | Surface water purchased | 1 | No available average above comparison levels |
| HELENDALE COMMUNITY SERVICE DISTRICT | CA3610112 | 6,347 | Ground water | 2 | Above an EPA comparison level |
| HELIX WATER DISTRICT | CA3710010 | 277,668 | Surface water | 1 | No available average above comparison levels |
| HEMET, CITY OF | CA3310016 | 33,828 | Surface water purchased | 3 | No available average above comparison levels |
| HERITAGE RANCH CSD | CA4010012 | 2,956 | Surface water | 1 | No available average above comparison levels |
| HESPERIA WD | CA3610024 | 100,744 | Ground water | 15 | Above an EPA comparison level |
| HI DESERT WD | CA3610073 | 26,411 | Ground water | 7 | No available average above comparison levels |
| HIDDEN VALLEY LAKE CSD | CA1710015 | 6,235 | Ground water | 1 | No available average above comparison levels |
| HIGHLANDS MUTUAL WATER COMPANY | CA1710003 | 7,772 | Surface water | 1 | No available average above comparison levels |
| HILMAR COUNTY WATER DISTRICT | CA2410012 | 5,504 | Ground water | 1 | No available average above comparison levels |
| HOLLISTER, CITY OF | CA3510001 | 26,017 | Surface water purchased | 6 | No available average above comparison levels |
| HOLTVILLE, CITY OF | CA1310005 | 6,355 | Surface water purchased | 1 | No available average above comparison levels |
| HUGHSON, CITY OF | CA5010008 | 7,481 | Ground water | 3 | No available average above comparison levels |
| HUMBOLDT C.S.D. | CA1210009 | 19,807 | Ground water | 4 | No available average above comparison levels |
| HUNTINGTON PARK-CITY, WATER DEPT. | CA1910049 | 15,437 | Surface water purchased | 6 | Above an EPA comparison level |
| HURON, CITY OF | CA1010044 | 9,306 | Surface water | 1 | No available average above comparison levels |
| Hoopa Valley-Wide System | 090605126 | 3,500 | Surface water | 1 | No available average above comparison levels |
| INDIAN WELLS VALLEY W.D. | CA1510017 | 41,580 | Ground water | 9 | No available average above comparison levels |
| INDIO WATER AUTHORITY | CA3310020 | 84,757 | Ground water | 13 | No available average above comparison levels |
| INGLEWOOD- CITY, WATER DEPT. | CA1910051 | 80,824 | Surface water purchased | 2 | No available average above comparison levels |
| IRVINE RANCH WATER DISTRICT | CA3010092 | 444,800 | Surface water | 8 | No available average above comparison levels |
| IVANHOE PUBLIC UTILITY DIST | CA5410019 | 4,580 | Ground water | 4 | No available average above comparison levels |
| JACKSON VALLEY IRRIGATION DISTRICT | CA0300037 | 3,553 | Surface water | 1 | No available average above comparison levels |
| JOSHUA BASIN WATER DISTRICT | CA3610025 | 6,640 | Ground water | 5 | No available average above comparison levels |
| JURUPA COMMUNITY SD | CA3310021 | 135,093 | Surface water purchased | 8 | No available average above comparison levels |
| KELSEYVILLE CO WATERWORKS DISTRICT 3 | CA1710007 | 4,102 | Ground water | 4 | No available average above comparison levels |
| KERMAN, CITY OF | CA1010018 | 17,256 | Ground water | 5 | No available average above comparison levels |
| KERN VALLEY STATE PRISON | CA1510802 | 5,000 | Ground water | 1 | No available average above comparison levels |
| KEYES COMMUNITY SERVICES DIST. | CA5010009 | 5,672 | Ground water | 1 | No available average above comparison levels |
| KINGSBURG, CITY OF | CA1010019 | 13,540 | Ground water | 7 | No available average above comparison levels |
| KIRKWOOD MEADOWS PUBLIC UTILITY DISTRICT | CA0210002 | 7,851 | Ground water | 4 | No available average above comparison levels |
| KONOCTI COUNTY WATER DISTRICT | CA1710006 | 5,928 | Surface water | 1 | No available average above comparison levels |
| LA CANADA IRRIGATION DIST. | CA1910054 | 9,300 | Surface water purchased | 1 | No available average above comparison levels |
| LA CUMBRE MUTUAL WATER CO | CA4210024 | 4,861 | Surface water purchased | 3 | No available average above comparison levels |
| LA HABRA HEIGHTS CWD | CA1910218 | 5,325 | Surface water purchased | 2 | Above an EPA comparison level |
| LA PUENTE VALLEY CWD | CA1910060 | 8,243 | Ground water | 1 | No available average above comparison levels |
| LA VERNE, CITY WD | CA1910062 | 31,334 | Surface water purchased | 4 | No available average above comparison levels |
| LAGUNA BEACH COUNTY WD | CA3010017 | 18,404 | Surface water purchased | 2 | No available average above comparison levels |
| LAKE ALMANOR COUNTRY CLUB MWC | CA3210006 | 6,000 | Ground water | 5 | No available average above comparison levels |
| LAKE ARROWHEAD CSD | CA3610005 | 7,038 | Surface water | 2 | Above an EPA comparison level |
| LAKE HEMET MWD | CA3310022 | 52,913 | Ground water | 10 | No available average above comparison levels |
| LAKEPORT, CITY OF | CA1710004 | 4,762 | Surface water | 2 | No available average above comparison levels |
| LAKESIDE WD | CA3710013 | 35,500 | Surface water purchased | 2 | Above an EPA comparison level |
| LAKESIDE WOODS MUTUAL WATER CO | CA4500013 | 310 | Ground water | 1 | No available average above comparison levels |
| LAKEWOOD - CITY, WATER DEPT. | CA1910239 | 66,135 | Ground water | 3 | Above an EPA comparison level |
| LAMONT PUBLIC UTILITY DIST | CA1510012 | 19,057 | Ground water | 6 | No available average above comparison levels |
| LAS FLORES WATER CO. | CA1910061 | 4,847 | Surface water purchased | 1 | No available average above comparison levels |
| LAS VIRGENES MWD | CA1910225 | 72,602 | Surface water | 4 | No available average above comparison levels |
| LATON COMMUNITY SERVICES DISTRICT | CA1010020 | 1,151 | Ground water | 3 | No available average above comparison levels |
| LEMOORE NAVAL AIR STATION | CA1610700 | 15,000 | Surface water | 1 | No available average above comparison levels |
| LEMOORE, CITY OF | CA1610005 | 27,185 | Ground water | 4 | No available average above comparison levels |
| LIBERTY UTILITIES (AV RANCHOS) CORP. | CA3610003 | 64,469 | Ground water | 10 | No available average above comparison levels |
| LIBERTY UTILITIES - BELLFLOWER-NORWALK | CA1910211 | 72,624 | Surface water purchased | 7 | Above an EPA comparison level |
| LIBERTY UTILITIES - COMPTON | CA1910021 | 26,371 | Surface water purchased | 4 | No available average above comparison levels |
| LIBERTY UTILITIES - LYNWOOD | CA1910161 | 24,701 | Surface water purchased | 3 | Above an EPA comparison level |
| LINDA COUNTY WATER DISTRICT | CA5810002 | 21,654 | Ground water | 4 | No available average above comparison levels |
| LINDSAY, CITY OF | CA5410006 | 12,659 | Surface water | 3 | Above an EPA comparison level |
| LITTLEROCK CREEK IRRIGATION DIST. | CA1910064 | 3,040 | Ground water | 5 | No available average above comparison levels |
| LODI, CITY OF | CA3910004 | 68,272 | Surface water | 25 | Above an EPA comparison level |
| LOMA LINDA UNIVERSITY | CA3600152 | 15,368 | Ground water | 3 | No available average above comparison levels |
| LOMA LINDA, CITY OF | CA3610013 | 25,129 | Ground water | 5 | No available average above comparison levels |
| LOMITA-CITY, WATER DEPT. | CA1910073 | 20,256 | Surface water purchased | 2 | No available average above comparison levels |
| LOMPOC-CITY WATER UTILITY DIV | CA4210006 | 40,473 | Surface water | 2 | No available average above comparison levels |
| LONG BEACH-CITY, WATER DEPT. | CA1910065 | 466,772 | Surface water purchased | 2 | No available average above comparison levels |
| LOS ANGELES CWWD 36-VAL VERDE | CA1910185 | 6,376 | Surface water purchased | 1 | No available average above comparison levels |
| LOS ANGELES CWWD 37-ACTON | CA1910248 | 4,805 | Surface water purchased | 1 | No available average above comparison levels |
| LOS ANGELES CWWD 40, REG. 38-LAKE LA | CA1910005 | 12,568 | Surface water purchased | 2 | No available average above comparison levels |
| LOS ANGELES CWWD 40,REG 4 & 34-LANCASTER | CA1910070 | 208,129 | Surface water purchased | 10 | No available average above comparison levels |
| LOS ANGELES-CITY, DEPT. OF WATER & POWER | CA1910067 | 3,875,566 | Surface water | 4 | No available average above comparison levels |
| LOS OSOS COMMUNITY SERVICES DISTRICT | CA4010016 | 7,086 | Ground water | 7 | Above an EPA comparison level |
| LUCERNE WATER CO. - CAL WATER SERVICE | CA1710005 | 2,129 | Surface water | 1 | No available average above comparison levels |
| LYNWOOD-CITY, WATER DEPT. | CA1910079 | 66,967 | Surface water purchased | 6 | Above an EPA comparison level |
| MADERA VALLEY WATER COMPANY | CA2010010 | 6,494 | Ground water | 5 | No available average above comparison levels |
| MALAGA COUNTY WATER DISTRICT | CA1010042 | 5,979 | Ground water | 3 | No available average above comparison levels |
| MAMMOTH CWD | CA2610001 | 8,234 | Surface water | 4 | No available average above comparison levels |
| MANHATTAN BEACH-CITY, WATER DEPT. | CA1910083 | 32,697 | Surface water purchased | 2 | No available average above comparison levels |
| MANTECA, CITY OF | CA3910005 | 84,928 | Surface water purchased | 11 | Above an EPA comparison level |
| MARIN MUNICIPAL WATER DISTRICT | CA2110002 | 186,895 | Surface water | 3 | No available average above comparison levels |
| MARINA COAST WATER DISTRICT | CA2710017 | 38,377 | Ground water | 3 | No available average above comparison levels |
| MAYWOOD MUTUAL WATER CO. #1 | CA1910084 | 5,500 | Surface water purchased | 2 | Above an EPA comparison level |
| MAYWOOD MUTUAL WATER CO. #2 | CA1910085 | 6,349 | Surface water purchased | 2 | No available average above comparison levels |
| MAYWOOD MUTUAL WATER CO. #3 | CA1910086 | 6,059 | Surface water purchased | 3 | Above an EPA comparison level |
| MCFARLAND, CITY OF | CA1510013 | 14,161 | Ground water | 3 | No available average above comparison levels |
| MCKINLEYVILLE C.S.D. | CA1210016 | 16,900 | Ground water purchased | 1 | No available average above comparison levels |
| MEADOW VISTA CWD | CA3110009 | 4,183 | Surface water | 1 | No available average above comparison levels |
| MEINERS OAKS CWD | CA5610005 | 4,200 | Surface water purchased | 4 | No available average above comparison levels |
| MENDOTA, CITY OF | CA1010021 | 11,404 | Ground water | 1 | No available average above comparison levels |
| MENLO PARK MUNICIPAL WATER | CA4110017 | 22,362 | Surface water purchased | 1 | No available average above comparison levels |
| MESA WATER DISTRICT | CA3010004 | 110,000 | Surface water purchased | 9 | No available average above comparison levels |
| MID-PENINSULA WATER DISTRICT | CA4110001 | 30,609 | Surface water purchased | 1 | No available average above comparison levels |
| MILLVIEW COUNTY WATER DISTRICT | CA2310006 | 5,500 | Surface water | 3 | No available average above comparison levels |
| MISSION HILLS CSD | CA4210019 | 3,600 | Ground water | 1 | No available average above comparison levels |
| MISSION SPRINGS WD | CA3310008 | 43,484 | Ground water | 7 | No available average above comparison levels |
| MODESTO, CITY OF | CA5010010 | 218,771 | Surface water purchased | 42 | Above an EPA comparison level |
| MOJAVE PUD | CA1510014 | 4,699 | Surface water purchased | 5 | No available average above comparison levels |
| MONROVIA-CITY, WATER DEPT. | CA1910090 | 37,931 | Ground water | 1 | Above an EPA comparison level |
| MONTARA WATER AND SANITARY DISTRICT | CA4110010 | 6,078 | Surface water | 3 | No available average above comparison levels |
| MONTE VISTA CWD | CA3610029 | 56,017 | Surface water purchased | 9 | Above an EPA comparison level |
| MONTEBELLO LAND & WATER CO. | CA1910091 | 26,554 | Ground water | 3 | Above an EPA comparison level |
| MONTEBELLO-CITY, WATER DEPT. | CA1910117 | 7,330 | Surface water purchased | 2 | No available average above comparison levels |
| MONTECITO WATER DIST | CA4210007 | 11,962 | Surface water | 7 | No available average above comparison levels |
| MONTEREY PARK-CITY, WATER DEPT. | CA1910092 | 62,183 | Ground water | 1 | No available average above comparison levels |
| MORRO BAY PW DEPT - WATER DIVISION | CA4010011 | 13,757 | Surface water purchased | 1 | No available average above comparison levels |
| MOULTON NIGUEL WATER DISTRICT | CA3010073 | 170,236 | Surface water purchased | 2 | No available average above comparison levels |
| MOUNTAIN HOUSE COMMUNITY SERVICES DIST. | CA3910027 | 24,948 | Surface water | 1 | No available average above comparison levels |
| MT. KONOCTI MUTUAL WATER COMPANY | CA1710014 | 4,360 | Surface water | 1 | No available average above comparison levels |
| MT. SHASTA, CITY OF | CA4710008 | 3,642 | Ground water | 3 | No available average above comparison levels |
| MUSCOY MWC NO. 1 | CA3610031 | 13,000 | Ground water | 1 | No available average above comparison levels |
| MYOMA DUNES MUTUAL WATER COMPANY | CA3310051 | 9,445 | Ground water | 5 | No available average above comparison levels |
| Morongo | 090600142 | 16,000 | Ground water | 5 | No available average above comparison levels |
| NAS NORTH ISLAND & NAB CORONADO | CA3710750 | 36,990 | Surface water purchased | 1 | No available average above comparison levels |
| NASA AMES RESEARCH CENTER | CA4300997 | 16,273 | Surface water purchased | 1 | No available average above comparison levels |
| NEEDLES, CITY OF | CA3610032 | 8,766 | Ground water | 3 | No available average above comparison levels |
| NEVADA ID - E. GEORGE, BANNER MOUNTAIN | CA2910004 | 17,154 | Surface water | 1 | No available average above comparison levels |
| NEVADA ID - LAKE OF PINES | CA2910014 | 6,870 | Surface water | 1 | No available average above comparison levels |
| NEVADA ID - LAKE WILDWOOD | CA2910023 | 9,108 | Surface water | 1 | No available average above comparison levels |
| NEVADA ID - LOMA RICA | CA2910006 | 14,072 | Surface water | 1 | No available average above comparison levels |
| NEVADA ID - NORTH AUBURN | CA3110026 | 6,870 | Surface water | 1 | No available average above comparison levels |
| NIPOMO COMM SERVICES DIST | CA4010026 | 13,771 | Surface water purchased | 5 | No available average above comparison levels |
| NORCO, CITY OF | CA3310025 | 25,068 | Surface water purchased | 6 | Above an EPA comparison level |
| NORTH COAST COUNTY WATER DIST | CA4110025 | 38,546 | Surface water purchased | 1 | No available average above comparison levels |
| NORTH MARIN WATER DISTRICT | CA2110003 | 61,691 | Surface water | 2 | No available average above comparison levels |
| NORTH TAHOE PUD - MAIN | CA3110001 | 6,321 | Surface water | 2 | No available average above comparison levels |
| NORTHSTAR C.S.D. | CA3110028 | 15,452 | Surface water | 1 | No available average above comparison levels |
| NORWALK - CITY, WATER DEPT. | CA1910191 | 20,283 | Surface water purchased | 6 | Above an EPA comparison level |
| NPS GGNRA | CA2110350 | 18,447 | Surface water purchased | 1 | No available average above comparison levels |
| NUEVO WATER COMPANY | CA3310026 | 6,733 | Surface water purchased | 1 | Above an EPA comparison level |
| OAK PARK WATER SERVICE | CA5610043 | 13,898 | Surface water purchased | 1 | No available average above comparison levels |
| OAKDALE, CITY OF | CA5010014 | 23,235 | Ground water | 7 | No available average above comparison levels |
| OCEANO COMM SERVICES DIST. | CA4010005 | 7,601 | Surface water purchased | 3 | No available average above comparison levels |
| OCEANSIDE, CITY OF | CA3710014 | 171,483 | Surface water purchased | 2 | No available average above comparison levels |
| OILDALE MWC | CA1510015 | 44,899 | Surface water purchased | 3 | No available average above comparison levels |
| OJAI WATER SYSTEM | CA5610014 | 6,801 | Surface water purchased | 1 | No available average above comparison levels |
| OLIVEHURST PUBLIC U.D. | CA5810003 | 16,595 | Ground water | 3 | No available average above comparison levels |
| OLIVENHAIN MWD | CA3710029 | 86,458 | Surface water purchased | 1 | No available average above comparison levels |
| OLYMPIA MOBILODGE | CA3410022 | 450 | Ground water | 1 | No available average above comparison levels |
| ONTARIO MUNICIPAL UTILITIES COMPANY | CA3610034 | 185,010 | Surface water purchased | 17 | Above an EPA comparison level |
| ORANGE VALE WATER COMPANY | CA3410016 | 16,861 | Surface water purchased | 1 | No available average above comparison levels |
| ORCHARD DALE WATER DISTRICT | CA1910101 | 25,000 | Ground water purchased | 1 | Above an EPA comparison level |
| OROSI PUBLIC UTILITY DISTRICT | CA5410008 | 8,300 | Ground water | 4 | No available average above comparison levels |
| OTAY WATER DISTRICT | CA3710034 | 238,008 | Surface water purchased | 2 | No available average above comparison levels |
| OXNARD WATER DEPT | CA5610007 | 200,232 | Surface water purchased | 3 | No available average above comparison levels |
| PADRE DAM MWD | CA3710037 | 93,980 | Surface water purchased | 2 | No available average above comparison levels |
| PAJARO COMMUNITY SERVICES DISTRICT | CA2710020 | 6,500 | Ground water | 1 | No available average above comparison levels |
| PALM RANCH IRRIGATION DIST. | CA1910103 | 5,507 | Surface water purchased | 1 | No available average above comparison levels |
| PALMDALE WATER DIST. | CA1910102 | 126,804 | Surface water | 5 | No available average above comparison levels |
| PARADISE IRRIGATION DISTRICT | CA0410007 | 9,142 | Surface water | 2 | No available average above comparison levels |
| PARAMOUNT - CITY, WATER DEPT. | CA1910105 | 55,200 | Surface water purchased | 2 | No available average above comparison levels |
| PASADENA-CITY, WATER DEPT. | CA1910124 | 164,344 | Surface water purchased | 4 | No available average above comparison levels |
| PASO ROBLES WATER DEPARTMENT | CA4010007 | 31,176 | Surface water | 12 | Above an EPA comparison level |
| PATTERSON TRACT CSD | CA5402038 | 550 | Ground water | 1 | No available average above comparison levels |
| PATTERSON, CITY OF | CA5010017 | 24,977 | Ground water | 6 | No available average above comparison levels |
| PETALUMA, CITY OF | CA4910006 | 60,781 | Ground water | 1 | No available average above comparison levels |
| PETER PITCHESS HONOR RANCHO DETN. CTR | CA1900046 | 7,000 | Ground water | 1 | Above an EPA comparison level |
| PHELAN PINON HILLS CSD | CA3610120 | 24,285 | Ground water | 7 | No available average above comparison levels |
| PICO RIVERA - CITY, WATER DEPT. | CA1910042 | 40,600 | Ground water | 8 | Above an EPA comparison level |
| PICO WD | CA1910125 | 22,051 | Ground water | 4 | Above an EPA comparison level |
| PINEDALE COUNTY WATER DISTRICT | CA1010026 | 16,736 | Ground water | 5 | Above an EPA comparison level |
| PISMO BEACH WATER DEPARTMENT | CA4010008 | 8,036 | Surface water purchased | 3 | No available average above comparison levels |
| PLACER CWA - AUBURN/BOWMAN | CA3110005 | 27,294 | Surface water | 2 | No available average above comparison levels |
| PLACER CWA - FOOTHILL | CA3110025 | 89,544 | Surface water | 2 | No available average above comparison levels |
| PLACERVILLE, CITY OF - MAIN | CA0910003 | 9,224 | Surface water purchased | 1 | No available average above comparison levels |
| PLANADA CSD | CA2410007 | 4,164 | Ground water | 6 | Above an EPA comparison level |
| PLEASANT VALLEY MUTUAL WATER CO | CA5610008 | 5,000 | Surface water purchased | 2 | Above an EPA comparison level |
| PLUMAS LAKE | CA5805001 | 10,464 | Ground water | 2 | No available average above comparison levels |
| POMONA - CITY, WATER DEPT. | CA1910126 | 151,713 | Surface water | 10 | Above an EPA comparison level |
| PONDEROSA BASIN MUTUAL WTR CO | CA2210002 | 798 | Ground water | 4 | No available average above comparison levels |
| PORT HUENEME WATER DEPT | CA5610009 | 21,407 | Surface water purchased | 1 | No available average above comparison levels |
| PORTERVILLE, CITY OF | CA5410010 | 63,487 | Ground water | 30 | Above an EPA comparison level |
| PORTERVILLE-JONES CORNER | CA5410048 | 339 | Ground water | 2 | No available average above comparison levels |
| POWAY, CITY OF | CA3710015 | 49,888 | Surface water | 1 | No available average above comparison levels |
| PRESIDIO OF SAN FRANCISCO | CA3810700 | 3,500 | Surface water | 1 | No available average above comparison levels |
| PURISSIMA HILLS WATER DISTRICT | CA4310021 | 6,245 | Surface water purchased | 1 | No available average above comparison levels |
| Pala North | 090605153 | 14,280 | Ground water | 4 | Above an EPA comparison level |
| Pauma | 090605012 | 5,700 | Ground water | 2 | No available average above comparison levels |
| Pechanga | 090605013 | 29,100 | Surface water purchased | 5 | No available average above comparison levels |
| QUARTZ HILL WATER DIST. | CA1910130 | 19,100 | Surface water purchased | 4 | No available average above comparison levels |
| RAMONA MUNICIPAL WD | CA3710019 | 37,047 | Surface water purchased | 1 | No available average above comparison levels |
| RANCHERITOS MWC | CA3600200 | 487 | Ground water | 3 | No available average above comparison levels |
| RANCHO CALIFORNIA WATER DISTRICT | CA3310038 | 146,147 | Surface water purchased | 38 | Above an EPA comparison level |
| RANCHO MURIETA COMMUNITY SERVI | CA3410005 | 5,728 | Surface water | 2 | No available average above comparison levels |
| REDLANDS CITY MUD-WATER DIV | CA3610037 | 78,025 | Surface water | 18 | Above an EPA comparison level |
| REDWOOD VALLEY COUNTY WATER DISTRICT | CA2310008 | 5,200 | Surface water | 1 | No available average above comparison levels |
| REEDLEY, CITY OF | CA1010027 | 26,076 | Ground water | 7 | No available average above comparison levels |
| RIALTO, CITY OF | CA3610038 | 54,453 | Surface water purchased | 9 | No available average above comparison levels |
| RINCON DEL DIABLO MWD (ID-1) | CA3710018 | 30,757 | Surface water purchased | 1 | No available average above comparison levels |
| RIO DELL, CITY OF | CA1210012 | 3,300 | Surface water | 2 | No available average above comparison levels |
| RIO LINDA/ELVERTA COMMUNITY WATER DIST | CA3410018 | 15,460 | Ground water | 12 | No available average above comparison levels |
| RIPON, CITY OF | CA3910007 | 15,741 | Ground water | 5 | Above an EPA comparison level |
| RIVERBANK, CITY OF | CA5010018 | 24,834 | Ground water | 9 | No available average above comparison levels |
| RIVERSIDE CSA #122-MESA VERDE | CA3310028 | 766 | Ground water | 1 | No available average above comparison levels |
| RIVERSIDE HIGHLAND WATER COMPANY | CA3610057 | 20,188 | Ground water | 3 | Above an EPA comparison level |
| RIVERSIDE, CITY OF | CA3310031 | 298,398 | Groundwater under influence of surface water | 1 | No available average above comparison levels |
| ROHNERT PARK, CITY OF | CA4910014 | 43,821 | Ground water | 8 | No available average above comparison levels |
| ROSAMOND CSD | CA1510018 | 17,711 | Surface water purchased | 2 | No available average above comparison levels |
| ROWLAND WATER DISTRICT | CA1910194 | 56,100 | Surface water purchased | 4 | No available average above comparison levels |
| RUBIDOUX COMMUNITY SD | CA3310044 | 36,827 | Ground water | 2 | No available average above comparison levels |
| RUBIO CANON LAND & WATER ASSOCIATION | CA1910140 | 9,215 | Surface water | 5 | Above an EPA comparison level |
| RUNNING SPRINGS WATER DISTRICT | CA3610062 | 5,268 | Surface water purchased | 10 | Above an EPA comparison level |
| RUSSIAN RIVER COUNTY WATER DISTRICT | CA4910008 | 4,150 | Ground water | 1 | No available average above comparison levels |
| Red Hawk Casino - Shingle Springs | 090600058 | 11,268 | Surface water purchased | 1 | No available average above comparison levels |
| Rincon Northern | 090600147 | 7,003 | Ground water | 3 | Above an EPA comparison level |
| SACRAMENTO SUBURBAN WATER DISTRICT | CA3410001 | 194,444 | Surface water purchased | 58 | No available average above comparison levels |
| SALINAS VALLEY STATE PRISON | CA2710851 | 2,930 | Ground water | 2 | No available average above comparison levels |
| SAN ANTONIO WATER COMPANY | CA3610085 | 3,441 | Ground water | 4 | No available average above comparison levels |
| SAN BERNARDINO CITY | CA3610039 | 214,665 | Ground water | 22 | No available average above comparison levels |
| SAN DIEGO, CITY OF | CA3710020 | 1,385,379 | Surface water | 4 | No available average above comparison levels |
| SAN DIEGUITO WD | CA3710021 | 40,405 | Surface water purchased | 1 | No available average above comparison levels |
| SAN FERNANDO-CITY, WATER DEPT. | CA1910143 | 23,946 | Ground water | 4 | No available average above comparison levels |
| SAN FRANCISCO REGIONAL WATER SYSTEM | CA3810001 | 600 | Surface water | 3 | No available average above comparison levels |
| SAN GABRIEL COUNTY WD | CA1910144 | 39,345 | Ground water | 5 | No available average above comparison levels |
| SAN GABRIEL VALLEY WATER CO.-EL MONTE | CA1910039 | 248,000 | Ground water | 9 | No available average above comparison levels |
| SAN GABRIEL VALLEY WATER CO.-MONTEBELLO | CA1910189 | 9,630 | Ground water purchased | 1 | No available average above comparison levels |
| SAN GABRIEL VALLEY WC - FONTANA | CA3610041 | 237,700 | Surface water | 11 | No available average above comparison levels |
| SAN JACINTO, CITY OF | CA3310032 | 18,950 | Ground water | 3 | No available average above comparison levels |
| SAN JOAQUIN COUNTY - LINCOLN VILLAGE | CA3910010 | 5,841 | Surface water purchased | 1 | No available average above comparison levels |
| SAN JOAQUIN COUNTY-MOKELUMNE ACRES | CA3910017 | 3,802 | Ground water | 5 | Above an EPA comparison level |
| SAN JOAQUIN RIVER CLUB INC | CA3910018 | 600 | Ground water | 1 | No available average above comparison levels |
| SAN JOAQUIN, CITY OF | CA1010034 | 4,060 | Ground water | 3 | No available average above comparison levels |
| SAN JOSE WATER | CA4310011 | 1,039,920 | Surface water | 19 | No available average above comparison levels |
| SAN JUAN WATER DISTRICT | CA3410021 | 29,598 | Surface water | 1 | No available average above comparison levels |
| SAN LORENZO VALLEY WATER DIST | CA4410014 | 21,145 | Surface water | 8 | No available average above comparison levels |
| SAN LUIS OBISPO WATER DEPARTMENT | CA4010009 | 47,788 | Surface water | 1 | No available average above comparison levels |
| SANTA ANA RIVER WATER COMPANY | CA3310033 | 5,848 | Ground water | 1 | No available average above comparison levels |
| SANTA CLARITA VALLEY W.A.-VALENCIA DIVIS | CA1910240 | 294,090 | Surface water | 9 | Above an EPA comparison level |
| SANTA CRUZ WATER DEPARTMENT | CA4410010 | 94,626 | Surface water | 3 | No available average above comparison levels |
| SANTA FE I.D. | CA3710023 | 21,578 | Surface water | 1 | No available average above comparison levels |
| SANTA FE SPRINGS - CITY, WATER DEPT. | CA1910245 | 19,219 | Surface water purchased | 2 | Above an EPA comparison level |
| SANTA MARGARITA WATER DISTRICT | CA3010101 | 168,289 | Surface water purchased | 2 | No available average above comparison levels |
| SANTA MARIA WATER DEPARTMENT | CA4210011 | 109,477 | Surface water purchased | 1 | No available average above comparison levels |
| SANTA MONICA-CITY, WATER DIVISION | CA1910146 | 89,947 | Surface water purchased | 3 | No available average above comparison levels |
| SANTA PAULA WATER SYSTEM | CA5610011 | 31,018 | Ground water | 3 | No available average above comparison levels |
| SANTA ROSA, CITY OF | CA4910009 | 175,396 | Ground water | 2 | No available average above comparison levels |
| SANTA YNEZ RIVER WATER CONS. DIST. ID#1 | CA4210020 | 7,022 | Surface water purchased | 10 | No available average above comparison levels |
| SATIVA-L.A. CWD | CA1910147 | 4,363 | Surface water purchased | 1 | Above an EPA comparison level |
| SBDNO COUNTY SERVICE AREA 64 | CA3610121 | 14,911 | Ground water | 2 | No available average above comparison levels |
| SBNDO COUNTY SERVICE AREA 70J | CA3610125 | 12,843 | Ground water | 2 | No available average above comparison levels |
| SCOTTS VALLEY WATER DISTRICT | CA4410013 | 11,197 | Ground water | 3 | No available average above comparison levels |
| SCWA - ARDEN PARK VISTA | CA3410002 | 10,101 | Ground water | 10 | Above an EPA comparison level |
| SCWA - LAGUNA/VINEYARD | CA3410029 | 184,896 | Surface water | 19 | Above an EPA comparison level |
| SCWA MATHER-SUNRISE | CA3410704 | 30,825 | Surface water purchased | 3 | No available average above comparison levels |
| SEA RANCH WATER COMPANY,THE (PUC) | CA4910007 | 1,160 | Surface water | 2 | No available average above comparison levels |
| SEBASTOPOL, CITY OF | CA4910011 | 7,522 | Ground water | 4 | No available average above comparison levels |
| SERRANO WATER DISTRICT | CA3010082 | 5,659 | Surface water purchased | 2 | No available average above comparison levels |
| SFPUC CITY DISTRIBUTION DIVISION | CA3810011 | 848,019 | Surface water purchased | 6 | No available average above comparison levels |
| SFWP-MINERS RANCH | CA0410006 | 22,664 | Surface water | 1 | No available average above comparison levels |
| SHAFTER, CITY OF | CA1510019 | 21,915 | Ground water | 6 | No available average above comparison levels |
| SHEEP CREEK WATER COMPANY | CA3610109 | 4,002 | Ground water | 1 | No available average above comparison levels |
| SIERRA MADRE-CITY, WATER DEPT. | CA1910148 | 11,000 | Surface water purchased | 2 | No available average above comparison levels |
| SIGNAL HILL - CITY, WATER DEPT. | CA1910149 | 11,848 | Surface water purchased | 3 | No available average above comparison levels |
| SLVWD - FELTON WATER SYSTEM | CA4410002 | 4,340 | Surface water | 2 | No available average above comparison levels |
| SO. CAL. EDISON CO.-SANTA CATALINA | CA1910006 | 3,822 | Surface water | 8 | No available average above comparison levels |
| SOLEDAD, CITY OF | CA2710011 | 19,455 | Ground water | 5 | No available average above comparison levels |
| SOLVANG WATER DIVISION | CA4210013 | 6,126 | Surface water purchased | 9 | No available average above comparison levels |
| SONOMA STATE UNIVERSITY | CA4910027 | 10,986 | Ground water | 1 | No available average above comparison levels |
| SONOMA, CITY OF | CA4910012 | 11,725 | Ground water | 6 | Above an EPA comparison level |
| SOQUEL CREEK WATER DISTRICT | CA4410017 | 40,809 | Surface water purchased | 14 | No available average above comparison levels |
| SOUTH COAST WATER DISTRICT | CA3010042 | 41,118 | Surface water purchased | 3 | No available average above comparison levels |
| SOUTH GATE-CITY, WATER DEPT. | CA1910152 | 76,443 | Surface water purchased | 5 | Above an EPA comparison level |
| SOUTH MESA WC | CA3310017 | 10,108 | Ground water | 8 | No available average above comparison levels |
| SOUTH MONTEBELLO IRRIGATION DIST. | CA1910153 | 15,021 | Ground water | 2 | Above an EPA comparison level |
| SOUTH TAHOE PUD - MAIN | CA0910002 | 100,000 | Ground water | 14 | Above an EPA comparison level |
| ST. HELENA, CITY OF | CA2810004 | 5,386 | Surface water | 3 | No available average above comparison levels |
| STALLION SPRINGS CSD | CA1510025 | 4,910 | Ground water | 4 | No available average above comparison levels |
| STANFORD UNIVERSITY | CA4310013 | 35,853 | Surface water purchased | 1 | No available average above comparison levels |
| SUBURBAN WATER SYSTEMS-GLENDORA | CA1910046 | 5,249 | Surface water purchased | 1 | No available average above comparison levels |
| SUBURBAN WATER SYSTEMS-LA MIRADA | CA1910059 | 56,793 | Surface water purchased | 3 | Above an EPA comparison level |
| SUBURBAN WATER SYSTEMS-SAN JOSE | CA1910205 | 168,843 | Surface water purchased | 7 | No available average above comparison levels |
| SUISUN-SOLANO WATER AUTHORITY | CA4810005 | 29,105 | Surface water | 1 | No available average above comparison levels |
| SUNNY SLOPE WATER CO. | CA1910157 | 25,252 | Ground water | 2 | No available average above comparison levels |
| SUNNYSLOPE COUNTY WATER DIST | CA3510003 | 24,954 | Surface water purchased | 7 | Above an EPA comparison level |
| SWEETWATER AUTHORITY | CA3710025 | 191,282 | Surface water | 3 | Above an EPA comparison level |
| SWEETWATER SPRINGS CWD - GUERNEVILLE | CA4910004 | 6,000 | Ground water | 1 | No available average above comparison levels |
| Suburban Water Systems - Whittier | CA1910174 | 66,045 | Ground water | 1 | Above an EPA comparison level |
| Sycuan | 090605024 | 12,350 | Surface water purchased | 1 | No available average above comparison levels |
| TAHOE CITY PUD - MAIN | CA3110010 | 5,661 | Ground water | 5 | No available average above comparison levels |
| TEHACHAPI, CITY OF | CA1510020 | 9,094 | Ground water | 1 | No available average above comparison levels |
| TEJON CASTAC WD - I5 & LAVAL RD | CA1503341 | 38,125 | Surface water | 1 | No available average above comparison levels |
| TEMESCAL VALLEY WATER DISTRICT | CA3310074 | 21,971 | Surface water purchased | 1 | No available average above comparison levels |
| TEMPLETON CSD | CA4010019 | 8,011 | Ground water | 5 | No available average above comparison levels |
| TERRA BELLA IRRIGATION DISTRICT - TBT | CA5410038 | 2,656 | Surface water | 1 | No available average above comparison levels |
| THERMALITO WATER & SEWER DIST | CA0410008 | 12,136 | Surface water | 5 | No available average above comparison levels |
| THOUSAND OAKS WATER DEPT | CA5610020 | 53,157 | Surface water purchased | 1 | No available average above comparison levels |
| THOUSAND TRAILS SAN BENITO PRESERVE | CA3500505 | 1,017 | Ground water | 2 | No available average above comparison levels |
| TIPTON COMMUNITY SERVICES DIST | CA5410014 | 2,543 | Ground water | 3 | No available average above comparison levels |
| TORRANCE-CITY, WATER DEPT. | CA1910213 | 106,183 | Surface water purchased | 3 | No available average above comparison levels |
| TOWN OF DISCOVERY BAY | CA0710009 | 16,790 | Ground water | 2 | No available average above comparison levels |
| TOWN OF HILLSBOROUGH | CA4110016 | 11,766 | Surface water purchased | 1 | No available average above comparison levels |
| TOWN OF YOUNTVILLE | CA2810007 | 2,787 | Surface water purchased | 1 | No available average above comparison levels |
| TRACT 180 MUTUAL WATER CO. | CA1910159 | 14,000 | Ground water | 2 | Above an EPA comparison level |
| TRACT 349 MUTUAL WATER CO. | CA1910160 | 8,700 | Ground water | 2 | Above an EPA comparison level |
| TRACY, CITY OF | CA3910011 | 96,609 | Surface water | 6 | No available average above comparison levels |
| TROUT GULCH MUTUAL WATER COMPANY | CA4400502 | 614 | Ground water | 1 | No available average above comparison levels |
| TRUCKEE-DONNER PUD, MAIN | CA2910003 | 36,730 | Ground water | 10 | No available average above comparison levels |
| TUD - COLUMBIA WATER SYSTEM | CA5510013 | 5,463 | Surface water | 2 | No available average above comparison levels |
| TUD - SONORA/JAMESTOWN WATER SYSTEM | CA5510001 | 11,054 | Surface water | 1 | No available average above comparison levels |
| TUD - UPPER BASIN WATER SYSTEM | CA5510012 | 13,280 | Surface water | 3 | No available average above comparison levels |
| TUD-WARDS FERRY RANCHES | CA5500363 | 62 | Ground water | 1 | No available average above comparison levels |
| TULARE, CITY OF | CA5410015 | 72,241 | Ground water | 22 | No available average above comparison levels |
| TURLOCK, CITY OF | CA5010019 | 72,682 | Surface water purchased | 5 | No available average above comparison levels |
| TWENTYNINE PALMS WATER DISTRICT | CA3610049 | 18,795 | Ground water | 7 | No available average above comparison levels |
| Table Mountain Rancheria | 090600154 | 10,675 | Surface water | 1 | No available average above comparison levels |
| UC Davis | CA5710009 | 49,616 | Surface water purchased | 7 | No available average above comparison levels |
| UKIAH, CITY OF | CA2310003 | 16,607 | Surface water | 6 | Above an EPA comparison level |
| UNION PUBLIC UTILITY DISTRICT | CA0510001 | 4,774 | Surface water | 1 | No available average above comparison levels |
| UPLAND, CITY OF | CA3610050 | 78,376 | Surface water | 10 | No available average above comparison levels |
| US ARMY FORT IRWIN | CA3610705 | 15,701 | Ground water | 1 | No available average above comparison levels |
| USMC - 29 PALMS | CA3610703 | 16,067 | Ground water | 1 | No available average above comparison levels |
| VALENCIA HEIGHTS WATER CO. | CA1910163 | 7,775 | Surface water purchased | 2 | No available average above comparison levels |
| VALLECITOS WD | CA3710002 | 113,500 | Surface water purchased | 2 | No available average above comparison levels |
| VALLEY CENTER MWD | CA3710026 | 29,938 | Surface water purchased | 1 | No available average above comparison levels |
| VALLEY COUNTY WATER DIST. | CA1910009 | 68,871 | Ground water | 3 | No available average above comparison levels |
| VALLEY OF THE MOON WATER DISTRICT | CA4910013 | 23,107 | Ground water | 7 | Above an EPA comparison level |
| VALLEY VIEW MUTUAL WATER CO. | CA1910165 | 4,613 | Ground water | 1 | No available average above comparison levels |
| VALLEY WATER CO. | CA1910166 | 10,070 | Surface water purchased | 1 | No available average above comparison levels |
| VANDENBERG VILLAGE COMM. SERV. DIST. | CA4210017 | 7,308 | Ground water | 1 | No available average above comparison levels |
| VAUGHN WC INC | CA1510029 | 37,189 | Ground water | 13 | No available average above comparison levels |
| VENTURA CWWD NO. 1 - MOORPARK | CA5610018 | 35,514 | Surface water purchased | 4 | No available average above comparison levels |
| VENTURA RIVER WATER DISTRICT | CA5610022 | 6,100 | Surface water purchased | 3 | No available average above comparison levels |
| VENTURA WATER DEPARTMENT | CA5610017 | 113,500 | Surface water | 4 | No available average above comparison levels |
| VENTURA WWD NO. 8 - SIMI VALLEY | CA5610023 | 94,738 | Surface water purchased | 2 | No available average above comparison levels |
| VERNON-CITY, WATER DEPT. | CA1910167 | 28,112 | Surface water purchased | 8 | No available average above comparison levels |
| VICTORVILLE WATER DISTRICT | CA3610052 | 135,983 | Surface water purchased | 15 | No available average above comparison levels |
| VISTA IRRIGATION DISTRICT | CA3710027 | 132,430 | Surface water | 2 | No available average above comparison levels |
| Viejas Community System | 090600158 | 9,600 | Ground water | 2 | No available average above comparison levels |
| WALNUT PARK MUTUAL WATER CO. | CA1910169 | 16,180 | Ground water | 1 | No available average above comparison levels |
| WALNUT VALLEY WATER DISTRICT | CA1910234 | 100,941 | Surface water purchased | 2 | No available average above comparison levels |
| WASCO ST. PRISON RECEPTION CTR | CA1510801 | 5,124 | Ground water | 1 | No available average above comparison levels |
| WASCO, CITY OF | CA1510021 | 22,757 | Ground water | 6 | No available average above comparison levels |
| WATSONVILLE, CITY OF | CA4410011 | 65,231 | Surface water | 14 | Above an EPA comparison level |
| WEAVERVILLE C.S.D. | CA5310001 | 3,975 | Surface water | 3 | Above an EPA comparison level |
| WEST KERN WATER DISTRICT | CA1510022 | 20,500 | Ground water | 1 | No available average above comparison levels |
| WEST VALLEY WATER DISTRICT | CA3610004 | 104,498 | Surface water | 9 | No available average above comparison levels |
| WESTBOROUGH COUNTY WATER DIST | CA4110027 | 13,486 | Surface water purchased | 1 | No available average above comparison levels |
| WESTERN HEIGHTS WATER COMPANY | CA3610053 | 7,705 | Surface water purchased | 1 | No available average above comparison levels |
| WESTERN MWD | CA3310049 | 86,062 | Surface water purchased | 3 | No available average above comparison levels |
| WESTERN MWD - MURRIETA DIVISION | CA3310036 | 17,453 | Surface water purchased | 3 | Above an EPA comparison level |
| WHITTIER-CITY, WATER DEPT. | CA1910173 | 49,954 | Ground water | 1 | Above an EPA comparison level |
| WILLITS, CITY OF | CA2310004 | 6,175 | Surface water | 1 | No available average above comparison levels |
| WILLOW COUNTY WATER DISTRICT | CA2310005 | 3,797 | Surface water purchased | 1 | No available average above comparison levels |
| WINDSOR, TOWN OF | CA4910017 | 25,561 | Ground water | 2 | No available average above comparison levels |
| WINE COUNTRY APARTMENTS | CA3900559 | 40 | Ground water | 1 | No available average above comparison levels |
| WINTON WATER & SANITARY DIST | CA2410010 | 9,745 | Ground water | 3 | No available average above comparison levels |
| WOODLAKE, CITY OF | CA5410020 | 7,846 | Ground water | 7 | No available average above comparison levels |
| YORBA LINDA WATER DISTRICT | CA3010037 | 84,292 | Surface water purchased | 3 | No available average above comparison levels |
| YOSEMITE SPRING PARK UTIL CO | CA2010005 | 5,300 | Ground water | 9 | Above an EPA comparison level |
| YREKA, CITY OF | CA4710011 | 7,825 | Surface water | 1 | No available average above comparison levels |
| YUCAIPA VALLEY WATER DISTRICT | CA3610055 | 52,010 | Surface water | 16 | No available average above comparison levels |
How the count works
What is included
Each active community water system with enough required samples for a yearly average is counted once, even if it is linked with several ZIP codes. Private wells are excluded, and UCMR 5 did not comprehensively monitor every small system.