Water Quality: San Diego, CA
5 water systems • 1,422,927 people served
Multiple Health ViolationsWater Quality Summary
San Diego is served by 5 public water systems with a combined service population of 1,422,927 people, and has 73 EPA Safe Drinking Water Act violations on record. Critically, 16 of those are health-based violations, meaning one or more contaminants were detected above EPA-established safe levels — a serious public health concern. San Diego's violation count is 52% above the national average for California. Contaminants associated with violations include E. coli, Fecal Coliform, Stage 2 DBP.
Contaminants Found
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)
Indicates direct fecal contamination; associated with diarrhea, cramps, nausea, and potential severe illness.
Common source: Human and animal fecal waste
EPA limit: Zero tolerance (any positive triggers violations)
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
Water Systems Serving San Diego
| System Name | PWSID | Source | Population | Violations |
|---|---|---|---|---|
| SAN DIEGO, CITY OF | CA3710020 | Surface Water | 1,385,379 | 36 |
| NAS NORTH ISLAND & NAB CORONADO | CA3710750 | Surface Water | 36,990 | 0 |
| BUTTERFIELD RANCH | CA3701184 | Groundwater | 353 | 34 |
| COTTONWOOD RIDGE MANUFACTURED HOUSING CO | CA4500107 | Groundwater | 205 | 2 |
| SAN DIEGO COUNTY WATER AUTHORITY | CA3710042 | Surface Water | 0 | 1 |
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.