WaterQ

City Water Quality Rankings in California

601 cities ranked by drinking water quality.

Popular city water quality comparisons

Trending Cities

#553
Bradley
County, CA
70 C
#554
Calexico
County, CA
70 C
#555
Huron
County, CA
70 C
#556
Mccloud
County, CA
70 C
#557
Paradise
County, CA
70 C
#558
Groveland
County, CA
69 C
#559
Avenal
County, CA
68 C
#560
Vista
County, CA
68 C
#561
Chico
County, CA
67 C
#562
Tuolumne
County, CA
67 C
#563
Lebec
County, CA
66 C
#564
Tipton
County, CA
66 C
#565
Kettleman City
County, CA
65 C
#566
Lancaster
County, CA
64 C
#567
Banning
County, CA
62 C
#568
Portola
County, CA
62 C
#569
Salinas
County, CA
62 C
#570
Porterville
County, CA
61 C
#571
Signal Hill
County, CA
60 C
#572
Pine Valley
County, CA
57 D
#573
Norco
County, CA
54 D
#574
Pala
County, CA
54 D
#575
Chino
County, CA
53 D
#576
Colusa
County, CA
50 D

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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