Public Water Systems
7,249 active public water systems in CA, tracked from EPA's Safe Drinking Water Information System (SDWIS) across all 50 states. See our methodology.
| System Name | Location | Population | Violations | PFAS |
| Western Acres Mutual Water Company | Hanford, CA | 380 | 21 | - |
| Elk County Water District | Elk, CA | 380 | 10 | - |
| Bellevue Union Sch Dist-Bellevue School | Santa Rosa, CA | 380 | 11 | - |
| Berkeley Tuolumne Camp | Berkeley, CA | 380 | 30 | - |
| San Andreas Mutual Water Co | La Selva Beach, CA | 378 | 4 | - |
| Wp&a - King Water System | Lost Hills, CA | 376 | 8 | - |
| Las Deltas Mutual Water Company | Clovis, CA | 375 | 35 | - |
| Usda-Forest Service Hume Lake Campground | Overland Park, CA | 375 | 9 | - |
| Usfs - Hungry & Boulder Gulch Campground | Overland Park, CA | 375 | 22 | - |
| Nichols Farms | Hanford, CA | 375 | 6 | - |
| MD 73 Quartz Mountain | Madera, CA | 375 | 9 | - |
| Bates Elementary School | Rio Vista, CA | 375 | 14 | - |
| Prairie Elementary School | Redding, CA | 375 | 14 | - |
| Anderson Springs Csd | Middletown, CA | 373 | 31 | - |
| Golden State Water Morongo Delnorte | San Dimas, CA | 373 | 2 | - |
| Californian Mobile Home Park | Rancho Cucamonga, CA | 372 | 20 | - |
| True Leaf Farms, LLC. | San Juan Bautista, CA | 372 | 5 | - |
| Benbow-Del Oro W.C. | Chico, CA | 370 | 42 | - |
| Huttopia Six Sigma Campground | Lower Lake, CA | 370 | 0 | - |
| Oak Creek Mobile Home Park | Coarsegold, CA | 370 | 3 | - |
| Csp-Westport State Beach | Duncans Mills, CA | 370 | 6 | - |
| Smiley Park Country Club | Running Springs, CA | 370 | 10 | - |
| Westport County Water District | Westport, CA | 369 | 55 | - |
| Calvary Chapel Christian Camp | Green Valley Lake, CA | 369 | 7 | - |
| Burlington Cg-State Parks | Eureka, CA | 368 | 2 | - |
| Saviers Road Mutual Water Co | Port Hueneme, CA | 368 | 17 | - |
| Black Rascal Water Company | Merced, CA | 367 | 15 | - |
| Wildhorse Cafe WS | King City, CA | 367 | 1 | - |
| Usfs Baker/Deadman Cgd | Sonora, CA | 366 | 2 | - |
| Enos Lane Public Utility District | Bakersfield, CA | 365 | 63 | - |
| Nps Prns - Five Brooks | Point Reyes Station, CA | 365 | 6 | - |
| Usfs/Lassen Hat Creek Campgrnd | Susanville, CA | 365 | 10 | - |
| Mount Diablo State Park | Clayton, CA | 364 | 24 | - |
| Cdpr Four Rivers District-Basalt | Columbia, CA | 363 | 10 | - |
| Heights Mutual Water Company | Forestville, CA | 363 | 9 | - |
| Hidden Pines Campground | Fort Bragg, CA | 362 | 8 | - |
| Santa Margarita Ranch Headquarters | San Luis Obispo, CA | 362 | 0 | - |
| Yosemite RV Resort | Coarsegold, CA | 361 | 31 | - |
| Monterey Mushrooms | Morgan Hill, CA | 361 | 21 | - |
| Sierra Village Mutual Water Co | Twain Harte, CA | 361 | 12 | - |
| Klamath C.s.d. | Klamath, CA | 360 | 29 | - |
| Paradise Ranch MHP | Beverly Hills, CA | 360 | 34 | - |
| Hitchcock RD WS #01 | Salinas, CA | 360 | 3 | - |
| Grimmway Enterprises - Cal Organic Therm | Bakersfield, CA | 360 | 0 | - |
| Lake Morena Views MWC | Pasadena, CA | 360 | 54 | - |
| Yuima Municipal Water District | Pauma Valley, CA | 360 | 18 | - |
| Fowlers Campground-Stnf | Mt. Shasta, CA | 360 | 26 | - |
| Camp Jones Gulch | La Honda, CA | 357 | 8 | - |
| Canada Woods WC | Carmel, CA | 356 | 8 | Clean |
| Verde Vale Water Company | Anderson, CA | 356 | 14 | - |