Combined Uranium violations in California
53 active public water systems in California had a Combined Uranium violation in the past three years, 9 of them in the latest quarter of EPA's data. What Combined Uranium is and why it matters.
Systems with a Combined Uranium violation
Latest quarter first, then largest first| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
San Pasqual District a County |
1,225 | 1 | 0 | |
|
Madison Service Dist Yolo County |
876 | 8 | 1 | |
|
Daggett Comm Svcs Dist San Bernardino County |
795 | 3 | 1 | |
|
Csa 70 W-3 Hacienda San Bernardino County |
611 | 1 | 0 | |
|
Knoll Enterprises San Bernardino County |
500 | 6 | 2 | |
|
Csa 70-F Morongo San Bernardino County |
300 | 1 | 0 | |
|
Waukena Elementary School Tulare County |
220 | 3 | 1 | |
|
Sierra Linda Mutual Water CO Madera County |
200 | 3 | 1 | |
|
Fcwwd 40 Shaver Springs Fresno County |
196 | 1 | 0 | |
|
Corona, City of Corona · Riverside County |
169,380 | 6 | 0 | |
|
Yocha Dehe Potable Water System County |
12,800 | 2 | 0 | |
|
Big River Development Big River · County |
3,550 | 9 | 4 | |
|
Green Valley Mwc San Bernardino County |
2,993 | 1 | 0 | |
|
Pine Valley Mutual WC San Diego County |
2,574 | 1 | 0 | |
|
Tule River Reservation Main Tule River Reservation · County |
2,560 | 9 | 2 | |
|
Chemehuevi Water County |
2,200 | 4 | 0 | |
|
Lebec County Water District Kern County |
1,379 | 1 | 0 | |
|
Del Oro River Island Serv Terr #1 Tulare County |
1,277 | 2 | 0 | |
|
Descanso Community Water District San Diego County |
870 | 3 | 1 | |
|
Grizzly Lake Csd-Delleker Plumas County |
657 | 2 | 0 | |
|
Tradewind Water Assoc. Kern County |
632 | 2 | 1 | |
|
Riverdale Park Tract Csd Stanislaus County |
610 | 1 | 0 | |
|
Riverview Mobile Home Estates Stanislaus County |
540 | 2 | 0 | |
|
Ceres Unified/westport School Stanislaus County |
450 | 2 | 0 | |
|
Big Sandy Rancheria Big Sandy Rancheria · County |
408 | 5 | 2 | |
|
Twin Lakes Resort San Diego County |
400 | 5 | 2 | |
|
Campo Elementary School San Diego County |
300 | 3 | 0 | |
|
Oakvale Park San Diego County |
260 | 3 | 0 | |
|
Ramona Oaks RV Resort San Diego County |
250 | 4 | 0 | |
|
Rainbird Valley Mwc Kern County |
238 | 2 | 0 | |
|
California Portland Cement Kern County |
200 | 1 | 0 | |
|
Old River Mutual Water Company Kern County |
130 | 3 | 0 | |
|
Lamanuzzi Pantaleo CS Dehy Madera County |
125 | 1 | 0 | |
|
Old Campo Campo Indian Reservation · County |
102 | 3 | 0 | |
|
Guatay Mutual Benefit Corporation San Diego County |
100 | 4 | 1 | |
|
MD 42 Still Meadow Madera County |
100 | 2 | 0 | |
|
Willowside Terrace Water Association San Diego County |
100 | 2 | 1 | |
|
Pit River Montgomery Creek Rancheria Montgomery Creek Rancheria · County |
90 | 11 | 0 | |
|
John Hovannisian Water System Madera County |
80 | 8 | 1 | |
|
Shackleford Creek Community Water System County |
80 | 5 | 0 | |
|
Pike Ranch Mutual Water CO Madera County |
74 | 4 | 1 | |
|
La Posta Upper County |
73 | 4 | 0 | |
|
Rancho Villanueva LLC County |
68 | 5 | 1 | |
|
South Campo County |
63 | 5 | 0 | |
|
Aguirre MHP County |
60 | 10 | 0 | |
|
Martin's Mobile Home Court Stanislaus County |
60 | 2 | 1 | |
|
Bass Lake Annex 3 Madera County |
42 | 1 | 0 | |
|
Pine Hill Egg Ranch San Diego County |
40 | 3 | 1 | |
|
Indian Hills Camp San Diego County |
36 | 2 | 0 | |
|
R.s. Mutual Water Company Kern County |
35 | 3 | 0 |
About this data
A system is counted once if any of its violations in the past three years involved Combined Uranium, including monitoring and reporting lapses. Rules violated and status in the table are for the whole system, not Combined Uranium 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.