Tapcensus

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.

Health effects: Uranium poses both radiological and chemical health risks. Chronic exposure is primarily associated with kidney damage due to its chemical toxicity as a heavy metal. The radiological risk — increased cancer probability — is also present but secondary to the nephrotoxic concern at drinking water concentrations. There is no safe threshold for radiation exposure.

Systems with a Combined Uranium violation

Latest quarter first, then largest first
SystemServesStatusRules violated, 3 yrUnresolved
Two Twenty Four Mobile Home PK
Madera County 		35 3 2
South Kern Mutual Water Company
Kern County 		32 4 1
Shady Oaks Mobile Home Park LLC
Madera County 		23 2 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.