Tapcensus

Simazine violations in California

27 active public water systems in California had a Simazine violation in the past three years, 1 of them in the latest quarter of EPA's data. What Simazine is and why it matters.

Health effects: Chronic exposure to simazine is associated with potential cancer risk; EPA classifies it as a possible human carcinogen (Group C) based on animal studies. Blood and nervous system effects have also been observed in animal studies. Long-term exposure at levels above the MCL is the primary concern for public water system violations.

Systems with a Simazine violation

Latest quarter first, then largest first
SystemServesStatusRules violated, 3 yrUnresolved
South Campo
County
63 5 0
Corona, City of
Corona · Riverside County
169,380 6 0
City of Sunnyvale
Sunnyvale · Santa Clara County
157,566 5 0
Norco, City of
Norco · Riverside County
25,068 5 0
Quechan Casino Resort
County
2,950 6 0
Chemehuevi Water
County
2,200 4 0
Sierra Tahoe Main Lodge
El Dorado County
1,900 5 0
Richgrove Community Services District
Tulare County
1,617 8 3
Madison Service Dist
Yolo County
876 8 1
Madera MH & RV Park
Madera County
450 5 0
Havasu Water Company
County
361 11 4
Cacheville Service Dist
Yolo County
239 8 1
Foster Road Mutual Water Company
Santa Barbara County
150 4 0
Gold Beach Park
El Dorado County
134 2 0
Acton Conservation Camp #11
Los Angeles County
90 4 0
B K Lighting INC
Madera County
90 2 0
Pit River Montgomery Creek Rancheria
Montgomery Creek Rancheria · County
90 11 0
San Joaquin Wine Company
Madera County
90 2 0
Resource Center
Santa Barbara · Santa Barbara County
85 2 0
John Hovannisian Water System
Madera County
80 8 1
Rancho Villanueva LLC
County
68 5 1
Brookside MHP
San Bernardino County
65 7 3
Yosemite Lakes Community Church
Madera County
51 1 0
Madera Irrigation District
Madera County
50 4 2
Kyburz Mutual Water Company
El Dorado County
30 5 0
Moreton Bay Professional Plaza
Santa Barbara County
25 6 1
Silverfork School
El Dorado County
25 8 0
About this data

A system is counted once if any of its violations in the past three years involved Simazine, including monitoring and reporting lapses. Rules violated and status in the table are for the whole system, not Simazine 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.