Water Quality: Palo Alto, CA
2 water systems • 70,020 people served
Multiple Health ViolationsWater Quality Summary
Palo Alto is served by 2 public water systems with a combined service population of 70,020 people, and has 4 EPA Safe Drinking Water Act violations on record. Critically, 4 of those are health-based violations, meaning one or more contaminants were detected above EPA-established safe levels — a serious public health concern. Palo Alto's violation count is 92% below the national average for California. Contaminants associated with violations include E. coli, Fecal Coliform.
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)
Water Systems Serving Palo Alto
| System Name | PWSID | Source | Population | Violations |
|---|---|---|---|---|
| CITY OF PALO ALTO | CA4310009 | Surface Water | 67,231 | 3 |
| O'CONNOR TRACT CO-OPERATIVE WATER CO. | CA4110019 | Groundwater | 2,789 | 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.