Nitrate violations in California
524 active public water systems in California had a Nitrate violation in the past three years, 41 of them still unresolved. What Nitrate is and why it matters.
Systems with a Nitrate violation
Unresolved first, then largest first| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
Tule River Reservation Main Tule River Reservation · County |
2,560 | 9 | 2 | |
|
Rancho Pauma Mutual WC San Diego County |
899 | 1 | 0 | |
|
Musd-New Haven School San Joaquin County |
626 | 1 | 0 | |
|
Woodland Park Mutual Water CO San Luis Obispo County |
538 | 2 | 0 | |
|
Sky Forest Mwc San Bernardino County |
492 | 2 | 1 | |
|
East Orosi Community Services District Tulare County |
423 | 3 | 2 | |
|
Campo Church Road System (hud Homes) County |
400 | 3 | 0 | |
|
Denny Boys Water System San Joaquin County |
300 | 1 | 0 | |
|
Hope Elementary School District Tulare County |
264 | 1 | 0 | |
|
Jehovah's Witnesses Kingdom Hall Yolo County |
245 | 3 | 0 | |
|
Department of Water and Power San Bernardino County |
239 | 1 | 0 | |
|
Pleasant View West School Tulare County |
220 | 2 | 0 | |
|
Waukena Elementary School Tulare County |
220 | 3 | 1 | |
|
Gordon Acres Water CO San Bernardino County |
200 | 6 | 4 | |
|
Lemon Cove Water Company Tulare County |
168 | 2 | 1 | |
|
Bar H Mwc San Bernardino County |
155 | 5 | 4 | |
|
East Valley Farms Mutual Water Company Santa Barbara County |
142 | 1 | 0 | |
|
Institute of Mental Physics San Bernardino County |
120 | 3 | 1 | |
|
West Kingdom Hall of Jehovah's Witnesses San Joaquin County |
100 | 1 | 0 | |
|
McCoy RD WS #05 Monterey County |
92 | 1 | 0 | |
|
Encinal RD WS #01 Monterey County |
91 | 3 | 1 | |
|
Shackleford Creek Community Water System County |
80 | 5 | 0 | |
|
Harris Woolf Almonds-Ballico Merced County |
65 | 1 | 0 | |
|
Casa Ruiz Yolo County |
60 | 1 | 0 | |
|
Star Motel San Joaquin County |
53 | 1 | 0 | |
|
Davis Jusd Fairfield School Yolo County |
46 | 1 | 0 | |
|
Sierra Vista Association Tulare County |
43 | 3 | 1 | |
|
Delano Growers Grape Products Kern County |
41 | 1 | 0 | |
|
Carrisa Plains Elementary San Luis Obispo County |
40 | 1 | 0 | |
|
Fremont One San Joaquin County |
39 | 1 | 0 | |
|
Higuera Apartments San Luis Obispo County |
30 | 3 | 2 | |
|
Martinez Apartments San Joaquin County |
26 | 2 | 0 | |
|
Bonfire Village Hotel Yolo County |
25 | 1 | 0 | |
|
Bravo Farms Traver Tulare County |
25 | 3 | 0 | |
|
Creston Country Store San Luis Obispo County |
25 | 1 | 0 | |
|
Cuyama Lane Water Company San Luis Obispo County |
25 | 3 | 1 | |
|
Olde Towne San Joaquin County |
25 | 2 | 0 | |
|
OP Murphy & Sons WS Monterey County |
25 | 2 | 1 | |
|
Park Green Houses Water System San Joaquin County |
25 | 1 | 0 | |
|
San-I-Pak INC San Joaquin County |
25 | 1 | 0 | |
|
Spence RD WS #05 Monterey County |
25 | 1 | 0 | |
|
City of Stockton Stockton · San Joaquin County |
192,702 | 2 | 0 | |
|
Jalama Beach Park Santa Barbara County |
120,017 | 1 | 0 | |
|
Indio Water Authority Riverside County |
89,137 | 1 | 0 | |
|
Manteca, City of Manteca · San Joaquin County |
84,928 | 1 | 0 | |
|
Adelanto, City of Adelanto · San Bernardino County |
39,930 | 1 | 0 | |
|
Golden State Water Company Orcutt Santa Barbara County |
34,267 | 1 | 0 | |
|
San Diego Mountain Lodge San Diego County |
26,641 | 3 | 0 | |
|
South Bay Rod & Gun Club Inc. San Diego County |
18,900 | 1 | 0 | |
|
Pala North County |
14,280 | 3 | 1 |
About this data
A system is counted once if any of its violations in the past three years involved Nitrate, including monitoring and reporting lapses. Rules violated and status in the table are for the whole system, not Nitrate alone.
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. Retrieved from ECHO on Oct 11, 2026.