All water systems in California
7,380 systems
| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
Nojoqui Falls County Park Santa Barbara County |
1,502 | 1 | 0 | |
|
Antlers Shell / Subway Shasta County |
1,500 | 0 | 0 | |
|
Cal Trans Buttonwillow Sfty Rsra Kern County |
1,500 | 0 | 0 | |
|
California State University Fresno Fresno County |
1,500 | 0 | 0 | |
|
Camp Verdugo Oaks Boyscouts Los Angeles County |
1,500 | 0 | 0 | |
|
Hard Rock Casino Tejon County |
1,500 | 2 | 0 | |
|
Sonoma State University Sonoma County |
1,500 | 0 | 0 | |
|
Springville Pud Tulare County |
1,500 | 1 | 0 | |
|
U.s. Army Corps-Lake Mendo (kyen Cmpgrd) Mendocino County |
1,500 | 0 | 0 | |
|
Golden State Water Company Edna San Luis Obispo County |
1,495 | 0 | 0 | |
|
Del Rey Community Serv Dist Fresno County |
1,491 | 0 | 0 | |
|
Midway Heights C. W. D. Placer County |
1,491 | 0 | 0 | |
|
West Almanor M.w.c. Plumas County |
1,464 | 0 | 0 | |
|
Joshua Tree Lake Rv/camp San Bernardino County |
1,458 | 0 | 0 | |
|
Guadalupe Valley Mid San Mateo County |
1,455 | 0 | 0 | |
|
Suburban Water Systems-Covina Knolls Los Angeles County |
1,451 | 0 | 0 | |
|
Los Molinos Comm. Services Dist. Tehama County |
1,450 | 1 | 1 | |
|
Inverness Public Utility Dist Marin County |
1,445 | 1 | 1 | |
|
Cal AM Water Company Toro Monterey County |
1,442 | 0 | 0 | |
|
Ventura Cwwd No. 19 Somis Ventura County |
1,429 | 0 | 0 | |
|
Biola Community Services Dist Fresno County |
1,427 | 0 | 0 | |
|
Tahoe Keys Water Company El Dorado County |
1,420 | 0 | 0 | |
|
California Water Service Co.-Lancaster Los Angeles County |
1,416 | 0 | 0 | |
|
Csp-Mackerricher State Park Mendocino County |
1,416 | 0 | 0 | |
|
Big Bend Campground Mono County |
1,406 | 0 | 0 | |
|
Caltrans-Collier Rest Stop Siskiyou County |
1,400 | 0 | 0 | |
|
High Desert Detention Center San Bernardino County |
1,400 | 0 | 0 | |
|
Usfs/dinkey Creek Campground Fresno County |
1,400 | 0 | 0 | |
|
Arrowbear Park Cwd San Bernardino County |
1,396 | 0 | 0 | |
|
Hydesville Co. W.d. Humboldt County |
1,389 | 3 | 1 | |
|
Saddlebag Lake Campground Mono County |
1,384 | 0 | 0 | |
|
Tahoe City Pud Rubicon Tahoe City · El Dorado County |
1,384 | 0 | 0 | |
|
Lebec County Water District Kern County |
1,379 | 1 | 0 | |
|
Lassen Community College Dist. Lassen County |
1,375 | 0 | 0 | |
|
Cal AM Water Company Ambler Park Monterey County |
1,370 | 0 | 0 | |
|
East Fork Campground Mono County |
1,365 | 0 | 0 | |
|
French Camp Campground Mono County |
1,365 | 0 | 0 | |
|
Crystal Springs CG Alpine County |
1,364 | 0 | 0 | |
|
Mojave River Forks Regional Park San Bernardino County |
1,356 | 1 | 0 | |
|
Aptos High School Santa Cruz County |
1,348 | 1 | 1 | |
|
City of Modesto del Rio Modesto · Stanislaus County |
1,346 | 0 | 0 | |
|
Buttonwillow Cwd Kern County |
1,337 | 0 | 0 | |
|
Garden Acres Mutual Water CO Ventura County |
1,335 | 0 | 0 | |
|
Rusack Vineyards Santa Barbara County |
1,327 | 1 | 0 | |
|
Lower Lake County Water District Lake County |
1,326 | 2 | 0 | |
|
Usfs Old Isabella Auxiliary Dam WS Kern County |
1,320 | 0 | 0 | |
|
McCloud C.s.d. Siskiyou County |
1,317 | 3 | 2 | |
|
Rural North Vacaville Water District Solano County |
1,313 | 0 | 0 | |
|
Mission Springs Conference Center Santa Cruz County |
1,310 | 0 | 0 | |
|
Midway City Mutual WC Midway City · Orange County |
1,305 | 0 | 0 |
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.