California Water Quality Reports 2026
Is your California tap water safe to drink? Check water quality for 75 cities and find the best water filtration companies near you.
Common Water Quality Concerns in California
Water Quality Reports by City
Select your city to see EPA water data and find local filtration services.
Los Angeles
Pop: 3,979,576
San Diego
Pop: 1,423,851
San Jose
Pop: 1,021,795
San Francisco
Pop: 883,305
Fresno
Pop: 542,107
Sacramento
Pop: 524,943
Long Beach
Pop: 466,742
Oakland
Pop: 433,031
Bakersfield
Pop: 403,455
Anaheim
Pop: 350,365
Santa Ana
Pop: 310,227
Riverside
Pop: 314,998
Stockton
Pop: 320,804
Irvine
Pop: 307,670
Chula Vista
Pop: 275,487
Fremont
Pop: 230,504
Santa Clarita
Pop: 228,673
San Bernardino
Pop: 222,101
Modesto
Pop: 218,464
Moreno Valley
Pop: 212,751
Fontana
Pop: 214,547
Glendale
Pop: 196,543
Huntington Beach
Pop: 198,711
Santa Rosa
Pop: 178,127
Oceanside
Pop: 176,193
Rancho Cucamonga
Pop: 177,603
Ontario
Pop: 175,265
Santa Clara
Pop: 127,647
Garden Grove
Pop: 172,646
Elk Grove
Pop: 176,124
Corona
Pop: 157,136
Lancaster
Pop: 173,516
Palmdale
Pop: 169,450
Salinas
Pop: 163,542
Pomona
Pop: 151,348
Hayward
Pop: 162,954
Escondido
Pop: 151,038
Sunnyvale
Pop: 155,805
Torrance
Pop: 144,430
Pasadena
Pop: 138,699
Orange
Pop: 139,911
Fullerton
Pop: 139,132
Thousand Oaks
Pop: 126,966
Roseville
Pop: 147,773
Concord
Pop: 129,295
Simi Valley
Pop: 126,788
Santa Maria
Pop: 109,988
Victorville
Pop: 134,810
Visalia
Pop: 141,384
Berkeley
Pop: 124,321
El Monte
Pop: 113,748
Downey
Pop: 111,263
Costa Mesa
Pop: 112,174
Inglewood
Pop: 107,762
Carlsbad
Pop: 114,746
Ventura
Pop: 109,106
Fairfield
Pop: 119,881
West Covina
Pop: 106,098
Murrieta
Pop: 113,326
Richmond
Pop: 116,448
Norwalk
Pop: 105,549
Antioch
Pop: 115,291
Temecula
Pop: 110,003
Burbank
Pop: 107,337
Daly City
Pop: 104,901
El Cajon
Pop: 106,215
San Mateo
Pop: 105,661
Clovis
Pop: 120,124
Compton
Pop: 97,877
Rialto
Pop: 104,437
Vista
Pop: 101,638
South Gate
Pop: 94,396
Mission Viejo
Pop: 95,202
Vacaville
Pop: 103,078
Carson
Pop: 95,617
About California Drinking Water
Is California tap water safe? While California water utilities must meet EPA minimum standards, many contaminants are legally allowed at levels that health experts consider concerning. Each city's water quality varies based on source, treatment, and infrastructure age.
How to Find the Best Water Filtration in California
When choosing a water filtration company in California, consider:
- Free water testing — Reputable companies offer professional in-home testing
- Customized solutions — Your system should address your specific contaminants
- Whole-home vs. point-of-use — Whole-home systems protect every tap and shower
- Certification — Look for NSF-certified systems
- Warranty and service — Quality companies stand behind their work
Why California Residents Need Water Filtration
California's water infrastructure faces challenges from aging pipes, agricultural runoff, industrial contamination, and emerging pollutants like PFAS. Even when water leaves the treatment plant safely, it can pick up contaminants traveling through miles of pipes to your home.
A whole-home water filtration system ensures that every tap in your California home delivers clean, safe water — for drinking, cooking, bathing, and more.
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