WaterQ

City Water Quality Rankings in California

601 cities ranked by drinking water quality.

Popular city water quality comparisons

Trending Cities

#217
Vandenberg Sfb
County, CA
98 A
#218
Visalia
County, CA
98 A
#219
Wasco
County, CA
98 A
#220
Westlake Village
County, CA
98 A
#221
Wildomar
County, CA
98 A
#222
Woodland
County, CA
98 A
#223
Yucca Valley
County, CA
98 A
#224
Adelanto
County, CA
97 A
#225
Angwin
County, CA
97 A
#226
Apple Valley
County, CA
97 A
#227
Camarillo
County, CA
97 A
#228
Crescent City
County, CA
97 A
#229
Delano
County, CA
97 A
#230
Downey
County, CA
97 A
#231
Guerneville
County, CA
97 A
#232
Lakeport
County, CA
97 A
#233
Madera
County, CA
97 A
#234
Pacific Grove
County, CA
97 A
#235
Pasadena
County, CA
97 A
#236
Quartz Hill
County, CA
97 A
#237
Quincy
County, CA
97 A
#238
San Luis Obispo
County, CA
97 A
#239
Sonoma
County, CA
97 A
#240
29 Palms
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.

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