WaterQ

City Water Quality Rankings in California

601 cities ranked by drinking water quality.

Popular city water quality comparisons

Trending Cities

#409
Compton
County, CA
91 A
#410
Forest Falls
County, CA
91 A
#411
Forestville
County, CA
91 A
#412
Grand Terrace
County, CA
91 A
#413
King George
County, CA
91 A
#414
Los Banos
County, CA
91 A
#415
Mcfarland
County, CA
91 A
#416
Orland
County, CA
91 A
#417
Oxnard
County, CA
91 A
#418
Riverdale
County, CA
91 A
#419
Sacramento
County, CA
91 A
#420
Simi Valley
County, CA
91 A
#421
Arbuckle
County, CA
90 A
#422
Beale Afb
County, CA
90 A
#423
Brawley
County, CA
90 A
#424
Brentwood
County, CA
90 A
#425
Cambria
County, CA
90 A
#426
Daly City
County, CA
90 A
#427
Fall River Mills
County, CA
90 A
#428
Fowler
County, CA
90 A
#429
Fresno
County, CA
90 A
#430
La Habra
County, CA
90 A
#431
Merced
County, CA
90 A
#432
Oceanside
County, CA
90 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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