#25 of 51A
California Water Quality
California ranks #25 out of 51 states for tap water quality with a score of 83.7 out of 100.
Summary
Overall Score
83.7
out of 100
Cities Tested
765
cities
Cities w/ Violations
573
75% of cities
Avg Contaminants
2.6
above guidelines
Population
237.0M
people affected
Best Cities in California
Pop: 92,058Score: 100
2Weed
Pop: 5,324Score: 100
Pop: 9,500Score: 100
Pop: 1,313Score: 100
Pop: 4,720Score: 100
Cities Needing Improvement
Pop: 115,588Score: 65
Pop: 109,414Score: 65
Pop: 276,918Score: 70
Pop: 84,462Score: 70
Pop: 96,657Score: 70
Cities listed have the lowest water quality scores in California.
Get California Water Updates
We analyze new EPA data as it drops. Get the breakdown for California in your inbox.
Free forever. Unsubscribe anytime. We never share your email.
Frequently Asked Questions About California Water Quality
California ranks #25 out of 51 states and territories for water quality with a score of 83.7 out of 100 and a grade of A. A total of 765 cities were tested across the state.
Need contact data for California utilities?
Check Your City's Water Quality
See detailed water quality data and get personalized filter recommendations for your specific location.
Stay Informed About Your Water Quality
Get EPA reports, filter recommendations, and safety alerts for your area.
Join 10,000+ people protecting their families. Unsubscribe anytime.