Total Haloacetic Acids (HAA5) violations in California
120 active public water systems in California had a Total Haloacetic Acids (HAA5) violation in the past three years, 6 of them in the latest quarter of EPA's data. What Total Haloacetic Acids (HAA5) is and why it matters.
Systems with a Total Haloacetic Acids (HAA5) violation
Latest quarter first, then largest first| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
City of Millbrae Millbrae · San Mateo County |
22,795 | 1 | 0 | |
|
Lindsay, City of Lindsay · Tulare County |
12,659 | 1 | 0 | |
|
Cal AM Bass Lake Madera County |
3,066 | 1 | 0 | |
|
Chemeketa Park Mutual Water Company Santa Clara County |
346 | 1 | 0 | |
|
Peppermint Creek MHP Tuolumne County |
280 | 2 | 0 | |
|
Beach Creek Mobile Home Park Humboldt County |
67 | 1 | 1 | |
|
City of Anaheim Anaheim · Orange County |
350,254 | 1 | 0 | |
|
Oildale Mwc Kern County |
45,315 | 2 | 1 | |
|
Lakeside WD San Diego County |
35,500 | 1 | 0 | |
|
East Niles Csd Kern County |
32,517 | 2 | 1 | |
|
Hollister, City of Hollister · San Benito County |
26,598 | 1 | 0 | |
|
Exeter, City of Exeter · Tulare County |
11,169 | 1 | 0 | |
|
Casitas Municipal Water Dist Ventura County |
11,005 | 2 | 0 | |
|
Mammoth Cwd Mono County |
8,234 | 1 | 0 | |
|
Pismo Beach Water Department San Luis Obispo County |
7,944 | 2 | 0 | |
|
Ventura River Water District Ventura County |
6,100 | 1 | 0 | |
|
Northrop Grumman Corp. Los Angeles County |
5,764 | 1 | 0 | |
|
Calistoga, City of Calistoga · Napa County |
5,610 | 2 | 1 | |
|
St. Helena, City of St. Helena · Napa County |
5,386 | 2 | 1 | |
|
Running Springs Water District San Bernardino County |
5,268 | 1 | 0 | |
|
Stallion Springs Csd Kern County |
4,910 | 2 | 1 | |
|
Forestville Water District Sonoma County |
3,717 | 1 | 0 | |
|
Big River Development Big River · County |
3,550 | 9 | 4 | |
|
Groveland Community Serv Dist Tuolumne County |
3,400 | 2 | 1 | |
|
Heritage Ranch Csd San Luis Obispo County |
2,956 | 1 | 0 | |
|
Quechan Casino Resort County |
2,950 | 6 | 0 | |
|
Pixley Public Util Dist Tulare County |
2,772 | 1 | 0 | |
|
Tule River Reservation Main Tule River Reservation · County |
2,560 | 9 | 2 | |
|
Nacimiento Water Company San Luis Obispo County |
2,191 | 3 | 2 | |
|
Redding Rancheria County |
2,015 | 7 | 2 | |
|
Cabazon Water District Riverside County |
1,900 | 2 | 0 | |
|
Inyo County Pwd Lone Pine Inyo County |
1,835 | 4 | 1 | |
|
Bear River/singley Hill County |
1,530 | 4 | 0 | |
|
Hydesville Co. W.d. Humboldt County |
1,389 | 3 | 1 | |
|
Sbdno County Service Area 70 Cedar Glen San Bernardino County |
1,240 | 1 | 0 | |
|
Inyo County Pwd Independence Inyo County |
1,108 | 3 | 2 | |
|
Santa Rosa Rancheria Santa Rosa Rancheria · County |
1,000 | 5 | 1 | |
|
Hillsview Homes Stanislaus County |
887 | 1 | 0 | |
|
Bear River Tish Non Village Bear River - Tish Non Village · County |
650 | 2 | 0 | |
|
Mesquite Creek County |
650 | 5 | 1 | |
|
Jacumba Community SD San Diego County |
561 | 1 | 0 | |
|
Chiriaco Summit Water Dist. Riverside County |
544 | 1 | 0 | |
|
Cazadero Water Company, Inc. (puc) Sonoma County |
525 | 3 | 2 | |
|
Alturas Desert Rose Casino Alturas · County |
464 | 2 | 1 | |
|
Usmc Housing Coleville Mono County |
424 | 3 | 0 | |
|
Hhw&p Moccasin Compound-Sfpuc San Francisco County |
410 | 1 | 0 | |
|
Big Sandy Rancheria Big Sandy Rancheria · County |
408 | 5 | 2 | |
|
Forest Park Mwc San Bernardino County |
406 | 3 | 1 | |
|
Butte Creek Estates Mutual Water CO Butte County |
399 | 3 | 0 | |
|
South Kaweah Mutual Water Company Tulare County |
384 | 3 | 1 |
About this data
A system is counted once if any of its violations in the past three years involved Total Haloacetic Acids (HAA5), including monitoring and reporting lapses. Rules violated and status in the table are for the whole system, not Total Haloacetic Acids (HAA5) 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.