Nitrate violations in California
524 active public water systems in California had a Nitrate violation in the past three years, 41 of them in the latest quarter of EPA's data. What Nitrate is and why it matters.
Systems with a Nitrate violation
Latest quarter first, then largest first| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
Quiet Oaks Mobile Home Park San Diego County |
120 | 1 | 0 | |
|
Ripperdan Community Day School Madera County |
120 | 2 | 0 | |
|
Ventura Coastal, LLC Visalia Division Tulare County |
120 | 2 | 1 | |
|
Round Valley Health Clinic County |
119 | 7 | 3 | |
|
Grimmway Farms David Road Kern County |
114 | 2 | 0 | |
|
Foster Farms Chicken Livehaul (sycamore Merced County |
110 | 1 | 0 | |
|
Halcyon Water System San Luis Obispo County |
110 | 3 | 1 | |
|
Torres-Martinez Avenue 64 County |
110 | 1 | 0 | |
|
Oak Grove Mobile Home Park Los Angeles County |
109 | 1 | 0 | |
|
Usfs Hull Creek Campgd Tuolumne County |
108 | 1 | 0 | |
|
Valley Oaks MHP WS Monterey County |
108 | 1 | 0 | |
|
Jameson Ranch Camp Kern County |
106 | 3 | 0 | |
|
Laird Wine Studio Napa County |
106 | 1 | 0 | |
|
Handistop Market Fresno County |
105 | 1 | 0 | |
|
Mono Vista Ranch MHP Tuolumne County |
105 | 2 | 0 | |
|
Oak Heights W & R CO INC Monterey County |
105 | 1 | 0 | |
|
Palm Gas Mart Riverside County |
105 | 1 | 0 | |
|
Paso Robles RV Ranch San Luis Obispo County |
105 | 1 | 0 | |
|
Shiloh School District Stanislaus County |
105 | 1 | 0 | |
|
Zaca Lake Retreat Santa Barbara County |
105 | 1 | 0 | |
|
Eastern Sierra Tri County Fair Inyo County |
104 | 1 | 0 | |
|
Nps Hole in the Wall Campground San Bernardino County |
104 | 1 | 0 | |
|
Ice House Resort El Dorado County |
103 | 2 | 0 | |
|
Rj's Travel Center Tulare County |
103 | 1 | 0 | |
|
Rancho Santa Teresa MW Co. San Diego County |
102 | 2 | 0 | |
|
Alamo Discount Store Riverside County |
100 | 1 | 0 | |
|
Camp Nauvoo Water System El Dorado County |
100 | 1 | 0 | |
|
Descanso Junction San Diego County |
100 | 1 | 0 | |
|
Econo Lodge Inn and Suites El Dorado County |
100 | 1 | 0 | |
|
Fll Mutual El Dorado County |
100 | 1 | 0 | |
|
Fox Sparrow RV Park El Dorado County |
100 | 2 | 0 | |
|
Gar, Llc. Reedley · County |
100 | 1 | 0 | |
|
Gray's Mart and Gas El Dorado County |
100 | 2 | 0 | |
|
Guatay Mutual Benefit Corporation San Diego County |
100 | 4 | 1 | |
|
Kit Carson Lodge Amador County |
100 | 2 | 0 | |
|
North Trails Mutual Water Company Los Angeles County |
100 | 3 | 1 | |
|
People's Market & Deli Tulare County |
100 | 2 | 0 | |
|
Pioneer Market Madera County |
100 | 1 | 0 | |
|
Pioneer Park Water System El Dorado County |
100 | 2 | 0 | |
|
Pleasant Valley Campground Inyo County |
100 | 1 | 0 | |
|
Round Valley Admin. Complex County |
100 | 6 | 1 | |
|
Stockton Silver Lake Family Camp Amador County |
100 | 1 | 0 | |
|
Stumpy Meadows Campground El Dorado County |
100 | 1 | 0 | |
|
Table MT Chevron Madera County |
100 | 1 | 0 | |
|
Temalpakh Farm County |
100 | 1 | 0 | |
|
Yellow Jacket Campground El Dorado County |
100 | 1 | 0 | |
|
Villa Robles Water System San Benito County |
98 | 3 | 2 | |
|
Ocotillo Oasis, LLC San Diego County |
96 | 3 | 1 | |
|
Vierra Canyon WS #29 Monterey County |
96 | 1 | 0 | |
|
Yokohl Mutual Water CO Tulare County |
95 | 5 | 2 |
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.