City Water Quality Rankings in California
601 cities ranked by drinking water quality.
Popular city water quality comparisons
Trending Cities
#265
Mi Wuk Village
County, CA
96 A
#266 Monrovia
County, CA
96 A
#267 Morgann Hill
County, CA
96 A
#268 Nevada City
County, CA
96 A
#269 Oakland
County, CA
96 A
#270 Orangevale
County, CA
96 A
#271 Palo Alto
County, CA
96 A
#272 Patterson
County, CA
96 A
#273 Phelan
County, CA
96 A
#274 Pine Grove
County, CA
96 A
#275 Pine Mountain Club
County, CA
96 A
#276 Pleasanton
County, CA
96 A
#277 Point Mugu
County, CA
96 A
#278 Point Reyes Station
County, CA
96 A
#279 Redwood City
County, CA
96 A
#280 Rio Linda
County, CA
96 A
#281 Rohnert Park
County, CA
96 A
#282 San Jose
County, CA
96 A
#283 Santa Ynez
County, CA
96 A
#284 Strathmore
County, CA
96 A
#285 Tracy
County, CA
96 A
#286 Trinidad
County, CA
96 A
#287 Twin Bridges
County, CA
96 A
#288 Twin Peaks
County, CA
96 A
Frequently Asked Questions
How are city water quality rankings calculated in California?
WaterQ city rankings are based on EPA SDWIS data across local public water systems, including contaminant detections, compliance violations, and recency-weighted score signals.
Can I compare two cities in California?
Yes. Use the city comparison links on this page or open the Compare tool to evaluate two cities side by side on score, grade, and water system coverage.
How often does WaterQ refresh city data?
City-level metrics refresh when new EPA data is processed. Check city pages for latest score and violation context.