WaterQ

City Water Quality Rankings in California

599 cities ranked by drinking water quality.

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Popular city water quality comparisons

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Trending Cities

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#73
Marina
County, CA
100 A
#74
Martinez
County, CA
100 A
#75
Marysville
County, CA
100 A
#76
Maywood
County, CA
100 A
#77
Mckittrick
County, CA
100 A
#78
Millbrae
County, CA
100 A
#79
Moffett Field
County, CA
100 A
#80
Mojave
County, CA
100 A
#81
Moorpark
County, CA
100 A
#82
Mountain House
County, CA
100 A
#83
Mountain View
County, CA
100 A
#84
Mt. Baldy
County, CA
100 A
#85
Nice
County, CA
100 A
#86
Nipomo
County, CA
100 A
#87
Norwalk
County, CA
100 A
#88
Nuevo
County, CA
100 A
#89
Oakley
County, CA
100 A
#90
Oregon House
County, CA
100 A
#91
Perris
County, CA
100 A
#92
Pixley
County, CA
100 A
#93
Poplar
County, CA
100 A
#94
Ramona
County, CA
100 A
#95
Rancho Santa Fe
County, CA
100 A
#96
Ranhco Mirage
County, CA
100 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.

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