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 |
| Almond Grove Mobile Park | Chico, CA | 253 | 20 | - |
| Nid Scotts Flat Lake Reservoir | Grass Valley, CA | 253 | 48 | - |
| Branch Elementary School | Arroyo Grande, CA | 253 | 3 | - |
| Houghton-Kearney School | Fresno, CA | 252 | 34 | - |
| Clear Water Mutual Water Company | Kelseyville, CA | 252 | 46 | - |
| Susan Hills Estates WC | Susanville, CA | 252 | 8 | - |
| 132 Investments Water System | Tracy, CA | 252 | 18 | - |
| Sonoma County Parks-Vet. Memorial Beach | Santa Rosa, CA | 252 | 4 | - |
| Ruth Lake Recreation Area | Mad River, CA | 252 | 6 | - |
| Pardee Recreation Area | Valley Springs, CA | 251 | 3 | - |
| Royal Oaks Park WS | Salinas, CA | 251 | 38 | - |
| Lassen Vnp - Summit Lake | Mineral, CA | 251 | 2 | - |
| Camp Ritchie | Lancaster, CA | 250 | 8 | - |
| Camp Wolfeboro | Pleasant Hill, CA | 250 | 36 | - |
| Colusa Co. Service Area #2-Stonyford | City of Colusa, CA | 250 | 15 | - |
| Northcrest Trailer City | Stockton, CA | 250 | 27 | - |
| American Union School | Fresno, CA | 250 | 76 | - |
| Wench Creek Campground | Hollister, CA | 250 | 18 | - |
| Camp Sacramento | Sacramento, CA | 250 | 28 | - |
| Camp Sierra | Kingsburg, CA | 250 | 69 | - |
| Wishon Village | Shaver Lake, CA | 250 | 15 | - |
| Fresno Valves & Castings | Selma, CA | 250 | 11 | - |
| Dollar General 19853 - Squaw Valley | Lenexa, CA | 250 | 0 | - |
| Dollar General Store #15320 | Goodlettsville, CA | 250 | 4 | - |
| Plaza Elementary School | Orland, CA | 250 | 3 | - |
| Green Diamond Resource Company - Korbel | Korbel, CA | 250 | 5 | - |
| Astorgas Water System | Bishop, CA | 250 | 29 | - |
| Pond School Water System | Wasco, CA | 250 | 71 | - |
| V Lions Ops Water System | Wasco, CA | 250 | 36 | - |
| Countryside Mkt & Restrn-119 | Bakersfield, CA | 250 | 9 | - |
| Wonderful Nurseries, LLC | Shafter, CA | 250 | 14 | - |
| Soledad Mountain Project Water System | Mojave, CA | 250 | 14 | - |
| Shaffer Elementary School | Litchfield, CA | 250 | 5 | - |
| Dollar General Janesville | Goodlettsville, CA | 250 | 0 | - |
| Bass Lake Heights Mutual Water | Oakhurst, CA | 250 | 117 | - |
| East Acres Mutual Water Company | Firebaugh, CA | 250 | 90 | - |
| Sierra View School | Madera, CA | 250 | 35 | - |
| Jackass Rock Camp | Clovis, CA | 250 | 12 | - |
| Skywalker Ranch | Nicasio, CA | 250 | 9 | - |
| McPr-Cathey S Valley Park | Mariposa, CA | 250 | 12 | - |
| River Estates Mutual Water Company | Ukiah, CA | 250 | 6 | - |
| Ocean's Edge Estates | Fort Bragg, CA | 250 | 10 | - |
| Firebaugh Travel Plaza (SW) | Concord, CA | 250 | 24 | - |
| Altman Plants WS #04 -Esp 420 (Prev Cs1) | Salinas, CA | 250 | 76 | - |
| Washington School WS | Salinas, CA | 250 | 310 | - |
| Meyers Water Co. | Napa, CA | 250 | 38 | - |
| Hess Winery | Napa, CA | 250 | 15 | - |
| Pleasant Ridge School | Grass Valley, CA | 250 | 28 | - |
| Heather Glen Community Service Dist | Applegate, CA | 250 | 32 | - |
| Alpine Meadows Property Owners Asso | Colfax, CA | 250 | 32 | - |