County · California
Ventura County, California: drinking water records
This overview covers 29 ZIP codes and 68 community water systems in Ventura County. It also stands in for 1 ZIP codes whose utility has too little EPA data for a page of its own.
System population figures are summed from EPA registry records and can overlap where wholesalers and retail systems serve the same people. They are not a Census county-population estimate.
Water systems with the most complete records
| Water system | People served | PFAS survey results | PFAS found | Health-based violations | Lead, 9 in 10 homes at or below |
|---|---|---|---|---|---|
| Ventura Water Department CA5610017 | 113,500 | 360 | 2 | 1 | 0 ppb |
| Casitas Municipal Water Dist CA5610024 | 11,005 | 240 | 0 | 1 | 0 ppb |
| Ventura River Water District CA5610022 | 6,100 | 240 | 0 | 3 | 0 ppb |
| Oxnard Water Dept CA5610007 | 200,232 | 360 | 0 | 0 | 2.2 ppb |
| Ventura Wwd No. 8 - Simi Valley CA5610023 | 94,738 | 180 | 0 | 0 | 0 ppb |
| Cal American Water Co CA5610040 | 66,809 | 120 | 0 | 0 | 3 ppb |
| City of Thousand Oaks Water Department CA5610020 | 53,157 | 120 | 0 | 0 | 0 ppb |
| Camarillo Water Dept CA5610019 | 46,824 | 310 | 0 | 0 | 0 ppb |
| Golden State Water Company - Simi Valley CA5610059 | 45,128 | 180 | 0 | 0 | 0 ppb |
| Ventura Cwwd No. 1 - Moorpark CA5610018 | 35,514 | 270 | 0 | 0 | 0 ppb |
| Camrosa Water District CA5610063 | 32,700 | 360 | 2 | 0 | 0 ppb |
| City of Santa Paula CA5610011 | 31,018 | 180 | 0 | 0 | 0 ppb |
| Port Hueneme City Water Dept CA5610009 | 21,407 | 120 | 0 | 0 | 0 ppb |
| California Water Service Co - Westlake CA5610016 | 19,533 | 120 | 0 | 0 | 3 ppb |
| Fillmore Water Dept CA5610002 | 16,419 | 120 | 0 | 0 | 0 ppb |
| Triunfo Water & Sanitation District CA5610043 | 13,898 | 120 | 0 | 0 | 0 ppb |
| Ojai Water System CA5610014 | 6,801 | 120 | 0 | 0 | 0 ppb |
| Naval Base Ventura County, Point Mugu CA5610700 | 5,700 | 0 | 0 | 1 | 0 ppb |
| Pleasant Valley Mutual Water Co CA5610008 | 5,000 | 240 | 5 | 0 | 0 ppb |
| Channel Islands Beach CSD CA5610039 | 4,560 | 120 | 0 | 0 | 0 ppb |
| Meiners Oaks Cwd CA5610005 | 4,200 | 360 | 0 | 0 | 0 ppb |
| Vineyard Avenue Acres Mwc CA5610029 | 1,820 | 0 | 0 | 2 | 0 ppb |
| Vineyard Ave Estates Mwc CA5610056 | 1,200 | 0 | 0 | 1 | 0 ppb |
| Senior Canyon Mutual Water Co CA5601117 | 800 | 0 | 0 | 2 | 0 ppb |
| Siete Robles Mutual Water Co CA5601119 | 323 | 0 | 0 | 1 | 0 ppb |
ZIP reports in Ventura County
No ZIP report in this county is published yet.
These ZIP codes are covered by this overview because their utility has too little EPA data for a separate page: 93040.
Sources and scope
EPA UCMR 5 occurrence data, samples collected 2023-01-03 – 2026-06-17, final release, August 2026 (file dated Aug 28, 2026); EPA SDWIS via ECHO, 2026Q2 extract (file dated Jul 9, 2026); EPA service-area boundaries v3.0; Census 2020 ZCTAs. Page generated 2026-09-03.
Counts cover the systems that report this county to EPA. A water system may cross county lines. "Found" means at least one result at or above the laboratory reporting level; it is not a compliance finding.