WaterQ

City Water Quality Rankings in California

599 cities ranked by drinking water quality.

Popular city water quality comparisons

Trending Cities

#505
Hydesville
County, CA
84 B
#506
Ivanhoe
County, CA
84 B
#507
Olympic Valley
County, CA
84 B
#508
Pomona
County, CA
84 B
#509
Sanger
County, CA
84 B
#510
South Lake Tahoe
County, CA
84 B
#511
St. Helena
County, CA
84 B
#512
Talmage
County, CA
84 B
#513
Calistoga
County, CA
83 B
#514
La Grange
County, CA
83 B
#515
Arvin
County, CA
82 B
#516
Los Angeles
County, CA
82 B
#517
Paso Robles
County, CA
82 B
#518
South Gate
County, CA
82 B
#519
Trabuco Canyon
County, CA
82 B
#520
Dunsmuir
County, CA
80 B
#521
Gustine
County, CA
80 B
#522
Ione
County, CA
80 B
#523
Monterey Park
County, CA
80 B
#524
Newport Beach
County, CA
80 B
#525
Three Rivers
County, CA
80 B
#526
Bakersfield
County, CA
79 B
#527
California City
County, CA
79 B
#528
Lakeside
County, CA
79 B

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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