All water systems in California
7,380 systems
| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
City of Nevada City Nevada City · Nevada County |
3,148 | 0 | 0 | |
|
Amarillo Mutual Water Company Los Angeles County |
3,134 | 0 | 0 | |
|
Home Gardens County WD Riverside County |
3,095 | 0 | 0 | |
|
Placer Cwa Colfax Placer County |
3,073 | 0 | 0 | |
|
Madera CO Md10a-Madera Ranchos Madera County |
3,072 | 0 | 0 | |
|
Shasta C.s.d. Shasta County |
3,069 | 0 | 0 | |
|
Cal AM Bass Lake Madera County |
3,066 | 1 | 0 | |
|
Littlerock Creek Irrigation Dist. Los Angeles County |
3,066 | 1 | 0 | |
|
Madera CO Csa 22c Gunner Ranch Madera · Madera County |
3,050 | 0 | 0 | |
|
Green Valley Campground San Bernardino County |
3,029 | 0 | 0 | |
|
San Miguel Community Services District San Luis Obispo County |
3,019 | 0 | 0 | |
|
Petite Pantry Inyo County |
3,012 | 0 | 0 | |
|
Victory Ranch Riverside County |
3,008 | 0 | 0 | |
|
Burney Water District Shasta County |
3,000 | 1 | 1 | |
|
Caltrans-Boron Rest Stop Water System Kern County |
3,000 | 0 | 0 | |
|
Knott's Berry Farm Orange County |
3,000 | 0 | 0 | |
|
Santa Clara Valley Medical Center Santa Clara County |
3,000 | 3 | 2 | |
|
Smith Forks Water System Ventura County |
3,000 | 1 | 0 | |
|
Soboba County |
3,000 | 2 | 0 | |
|
Wild Water Adventures Fresno County |
3,000 | 1 | 0 | |
|
Cci Tehachapi Kern County |
2,993 | 0 | 0 | |
|
Green Valley Mwc San Bernardino County |
2,993 | 1 | 0 | |
|
Aromas Water District San Benito County |
2,988 | 0 | 0 | |
|
Naval Medical Center San Diego San Diego County |
2,981 | 0 | 0 | |
|
Heritage Ranch Csd San Luis Obispo County |
2,956 | 1 | 0 | |
|
Nps-Grant Grove Fresno County |
2,950 | 1 | 1 | |
|
Quechan Casino Resort County |
2,950 | 6 | 0 | |
|
Nps-Ash Mountain Tulare County |
2,930 | 2 | 1 | |
|
Salinas Valley State Prison Monterey County |
2,930 | 0 | 0 | |
|
Nice Mutual Water Company Lake County |
2,929 | 0 | 0 | |
|
Northgate 880 [sws] Sacramento County |
2,926 | 1 | 1 | |
|
Sutter Community S.d. Sutter County |
2,904 | 0 | 0 | |
|
Nps-Pinewood Water System Tulare County |
2,900 | 0 | 0 | |
|
Nps-Sheep Creek Fresno County |
2,900 | 0 | 0 | |
|
Palo Alto Park Mutual Water Company San Mateo County |
2,900 | 0 | 0 | |
|
Fcwwd 41/shaver Lake Fresno County |
2,859 | 0 | 0 | |
|
City of Vallejo-Lakes System Vallejo · Solano County |
2,800 | 0 | 0 | |
|
Land Projects Mutual Water Co. Los Angeles County |
2,800 | 1 | 0 | |
|
Lerdo Sheriff S Facility Kern County |
2,800 | 0 | 0 | |
|
Rio Cosumnes Correctional Center [sws] Sacramento County |
2,800 | 1 | 1 | |
|
Seaside Municipal Water System Monterey County |
2,800 | 0 | 0 | |
|
Lake Shastina C.s.d Siskiyou County |
2,790 | 1 | 1 | |
|
O'connor Tract Co-Operative Water Co. San Mateo County |
2,789 | 0 | 0 | |
|
Town of Yountville Napa County |
2,785 | 0 | 0 | |
|
North Yuba Water District Yuba County |
2,772 | 0 | 0 | |
|
Pixley Public Util Dist Tulare County |
2,772 | 1 | 0 | |
|
Riverdale Public Utility District Fresno County |
2,756 | 0 | 0 | |
|
Fort Hunter Liggett Monterey County |
2,753 | 0 | 0 | |
|
Tahoe City Pud Tahoe Cedars Placer County |
2,745 | 0 | 0 | |
|
Bishop Paiute-Shoshone Tribe Bishop Paiute-shoshone Reservation · County |
2,735 | 3 | 1 |
About this data
Rules violated counts the rules a system was in violation of in the past three years, including monitoring and reporting lapses; one rule can carry several violations. Unresolved is the number of those rules currently in violation at EPA's latest data refresh.
Source: the U.S. EPA's Enforcement and Compliance History Online system (ECHO), which publishes the federal Safe Drinking Water Information System. EPA's terms and values are shown as published. The California records are from EPA's data refresh of Oct 7, 2026; EPA refreshes this data quarterly, and states report to EPA with a lag of three to six months, so the newest violations may not appear yet.