Water Quality: Clovis, CA
8 water systems • 131,647 people served
Multiple Health ViolationsWater Quality Summary
Clovis is served by 8 public water systems with a combined service population of 131,647 people, and has 346 EPA Safe Drinking Water Act violations on record. Critically, 238 of those are health-based violations, meaning one or more contaminants were detected above EPA-established safe levels — a serious public health concern. Clovis's violation count is 621% above the national average for California. Contaminants associated with violations include Barium, Contaminant 4109, E. coli, Gross Alpha, Haloacetic Acids.
Contaminants Found
Increases blood pressure and causes cardiovascular effects with long-term exposure.
Common source: Natural rock deposits, oil drilling operations, coal power plant waste
EPA limit: 2 mg/L
Causes gastrointestinal illness; certain strains (e.g., O157:H7) can cause severe kidney failure and death.
Common source: Fecal contamination from humans or animals entering the water supply
EPA limit: Zero (no E. coli permitted in drinking water)
Alpha-emitting radioactive particles increase cancer risk, particularly from bone and other internal cancers.
Common source: Natural uranium and radium in geological formations
EPA limit: 15 pCi/L (excluding radon and uranium)
Linked to increased cancer risk and potential reproductive and developmental effects with long-term exposure.
Common source: Reaction of chlorine disinfectants with organic matter in treated water
EPA limit: 0.060 mg/L (60 ppb)
Hair loss, nail brittleness, and nervous system damage at elevated concentrations.
Common source: Natural geological deposits, mining discharges, oil refinery waste
EPA limit: 0.05 mg/L (50 ppb)
Trihalomethanes and haloacetic acids that increase cancer risk and may cause adverse reproductive outcomes.
Common source: Chlorine disinfection reacting with natural organic matter in source water
EPA limit: TTHM: 0.080 mg/L; HAA5: 0.060 mg/L
Total trihalomethanes are linked to increased risk of bladder cancer and adverse reproductive outcomes.
Common source: Reaction of chlorine disinfectants with naturally occurring organic matter in water
EPA limit: 0.080 mg/L (80 ppb)
Water Systems Serving Clovis
| System Name | PWSID | Source | Population | Violations |
|---|---|---|---|---|
| CITY OF CLOVIS | CA1010003 | Surface Water | 130,130 | 0 |
| SHAVER LAKE HEIGHTS MWC | CA1010053 | Groundwater | 836 | 43 |
| LAS DELTAS MUTUAL WATER COMPANY | CA1000054 | Groundwater | 375 | 18 |
| OLD RIVER MUTUAL WATER COMPANY | CA1500096 | Groundwater | 130 | 44 |
| KEELER COMMUNITY SERVICE DISTRICT | CA1400036 | Groundwater | 66 | 25 |
| SIERRA VISTA ASSOCIATION | CA5400964 | Groundwater | 43 | 90 |
| TWO TWENTY FOUR MOBILE HOME PK | CA2000592 | Groundwater | 35 | 87 |
| SOUTH KERN MUTUAL WATER COMPANY | CA1500344 | Groundwater | 32 | 39 |
Concerned About Your Water?
A home water filter can remove common contaminants. NSF-certified filters are tested against EPA standards.
Consider a reverse osmosis system for comprehensive filtration or a carbon filter for basic improvement.
Other Cities in California
Data Sources
Drinking water violation data from the EPA Safe Drinking Water Information System (SDWIS). Data includes all recorded violations for active community water systems.