Lead pipes by county in California
Lead, galvanized and unknown service lines reported by the water systems serving each California county.
| County | Lead | Galv. | Unknown | Systems |
|---|
| Alameda County | 0 | 3,935 | 14,546 | 7 |
| Alpine County | 0 | 0 | 215 | 3 |
| Amador County | 0 | 3 | 2,560 | 8 |
| Butte County | 0 | 0 | 26,352 | 11 |
| Calaveras County | 0 | 0 | 12 | 9 |
| Colusa County | 0 | 10 | 1,038 | 5 |
| Contra Costa County | 0 | 0 | 38 | 9 |
| Del Norte County | 0 | 0 | 186 | 6 |
| El Dorado County | 0 | 78 | 8,658 | 9 |
| Fresno County | 0 | 2 | 16,529 | 33 |
| Glenn County | 0 | 0 | 3,665 | 4 |
| Humboldt County | 0 | 9 | 5,056 | 22 |
| Imperial County | 0 | 0 | 13,721 | 13 |
| Inyo County | 0 | 1 | 2,332 | 9 |
| Kern County | 0 | 215 | 82,499 | 47 |
| Kings County | 0 | 42 | 1,244 | 9 |
| Lake County | 0 | 0 | 1,300 | 18 |
| Lassen County | 0 | 0 | 181 | 4 |
| Los Angeles County | 0 | 750 | 126,291 | 144 |
| Madera County | 0 | 1 | 138 | 20 |
| Marin County | 0 | 1 | 278 | 7 |
| Mariposa County | 0 | 0 | 274 | 3 |
| Mendocino County | 0 | 0 | 3,403 | 11 |
| Merced County | 0 | 3 | 4,292 | 13 |
| Modoc County | 0 | 0 | 1,500 | 2 |
| Mono County | 0 | 0 | 2,737 | 8 |
| Monterey County | 0 | 286 | 359 | 31 |
| Napa County | 0 | 63 | 634 | 8 |
| Nevada County | 0 | 154 | 13,850 | 9 |
| Orange County | 0 | 143 | 0 | 33 |
| Placer County | 0 | 0 | 16,615 | 31 |
| Plumas County | 0 | 201 | 438 | 8 |
| Riverside County | 0 | 128 | 10,890 | 40 |
| Sacramento County | 0 | 57 | 11,776 | 35 |
| San Benito County | 0 | 31 | 5 | 5 |
| San Bernardino County | 0 | 2,758 | 14,424 | 84 |
| San Diego County | 0 | 13 | 582 | 36 |
| San Francisco County | 0 | 653 | 450 | 3 |
| San Joaquin County | 0 | 0 | 0 | 18 |
| San Luis Obispo County | 0 | 1,035 | 25 | 31 |
| San Mateo County | 0 | 19 | 25,818 | 24 |
| Santa Barbara County | 0 | 125 | 19,969 | 21 |
| Santa Clara County | 0 | 24 | 60 | 22 |
| Santa Cruz County | 0 | 0 | 8,037 | 12 |
| Shasta County | 0 | 8 | 2,974 | 20 |
| Sierra County | 0 | 10 | 323 | 1 |
| Siskiyou County | 0 | 72 | 4,608 | 15 |
| Solano County | 0 | 101 | 41,131 | 13 |
| Sonoma County | 0 | 668 | 10,170 | 46 |
| Stanislaus County | 0 | 620 | 9,489 | 26 |
| Sutter County | 0 | 0 | 245 | 3 |
| Tehama County | 0 | 44 | 2,767 | 17 |
| Trinity County | 0 | 6 | 415 | 6 |
| Tulare County | 0 | 170 | 45,679 | 37 |
| Tuolumne County | 0 | 0 | 79 | 16 |
| Ventura County | 0 | 0 | 7,005 | 34 |
| Yolo County | 0 | 0 | 19,405 | 10 |
| Yuba County | 0 | 0 | 3,549 | 8 |
Systems serving several counties are counted in each. Source: EPA SDWIS service line inventory, 2026 Q3.