California
Ventura County drinking water quality
95 active public water systems serve 875,995 people in Ventura County. 58 are compliant, 37 had at least one EPA violation in the past three years, 0 are designated serious violators, and 17 carry a health flag.
Needs attention
7 more systems with a serious violator or health flag designation are in the lists below.
Community water systems
68 systems, largest first| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
U.s.n., San Nicolas Island |
187 | 0 | 0 | |
|
Navalair Mobile Home Park |
160 | 1 | 1 | |
|
Siesta Mobile Home Park |
160 | 2 | 1 | |
|
Elkins Ranch |
150 | 2 | 1 | |
|
Middle Road Mutual Water CO |
134 | 0 | 0 | |
|
San Cayetano Mutual Water CO |
109 | 0 | 0 | |
|
Solano Verde Mutual Water CO |
100 | 0 | 0 | |
|
Alturas Fillmore MHP |
99 | 0 | 0 | |
|
Tico Mutual Water CO |
72 | 0 | 0 | |
|
Community Mutual Water CO |
65 | 1 | 0 | |
|
South Mountain Mutual Water CO |
58 | 0 | 0 | |
|
Esterina Properties |
50 | 1 | 1 | |
|
Krotona Institute |
30 | 2 | 1 | |
|
Rincon Water & Road Works |
25 | 1 | 0 | |
|
Waters Road Domestic Users Group |
25 | 0 | 0 | |
|
Calleguas Municipal Water Dist |
0 | 0 | 0 | |
|
Port Hueneme Water Agency |
0 | 0 | 0 | |
|
United Wtr Cons Dist |
0 | 0 | 0 |
Non-community systems (27: schools, campgrounds, workplaces, restaurants)
These systems serve places people visit rather than homes.
| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
Smith Forks Water System |
3,000 | 1 | 0 | |
|
Rio Mesa High School/oxnard Uhs |
2,600 | 1 | 1 | |
|
Lake Piru Park Uwcd |
960 | 0 | 0 | |
|
Rio School Dist/rio del Valle School |
820 | 0 | 0 | |
|
Rio School Dist/ Rio Real School |
550 | 0 | 0 | |
|
Usfs Wheeler Gorge Campground |
500 | 0 | 0 | |
|
Glass House Camarillo Cultivation, LLC |
450 | 0 | 0 | |
|
Thomas Aquinas College |
382 | 1 | 0 | |
|
Laguna Vista School/oceanview School Dis |
377 | 0 | 0 | |
|
Vineyard Mutual Water Company/industrial |
259 | 0 | 0 | |
|
Foxfield Riding School |
120 | 0 | 0 | |
|
Dennison Park |
102 | 1 | 0 | |
|
Bouquet Multimedia |
100 | 0 | 0 | |
|
Ventura Farms |
100 | 0 | 0 | |
|
Nishi Quality Flowers, Inc. |
92 | 1 | 1 | |
|
The Ranch at Live Oak |
82 | 1 | 1 | |
|
GP Anacapa Foods, Llc. |
50 | 0 | 0 | |
|
Santa Clara School |
39 | 0 | 0 | |
|
Oxnard Pallet Company |
38 | 1 | 0 | |
|
Beedy Water Company, LLC |
35 | 0 | 0 | |
|
Camp Scheideck |
33 | 1 | 1 | |
|
Channel Islands National Park |
30 | 0 | 0 | |
|
Pyramid Flowers |
30 | 1 | 0 | |
|
Santa Clara Resources |
30 | 1 | 0 | |
|
Vulcan Materials Company Cal Mat |
30 | 1 | 1 | |
|
Usfs Chuchupate Ranger Station |
26 | 1 | 1 | |
|
State Ready Mix, Inc. Ventura |
25 | 1 | 1 |
Inactive systems (83, no longer operating or reporting)
Kept for the record and excluded from the county totals above. Browse inactive systems.
About this data
Totals cover active systems. Systems serving more than one county are counted in each county. EPA counts the rules a system was in violation of, not the individual violations; one rule can carry several.
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.