Napa, California Water Quality Report
Water quality data for 18 water systems serving 88,371 people.
Water Source
Detected Contaminants
No contaminant data available for this location.
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Compliance & Violations
Active Violations (30)
52
Jul 1, 2025
52
Jan 1, 2025
52
Jan 1, 2025
52
Jan 1, 2025
2E
Oct 17, 2024
4G
Oct 17, 2024
2E
Oct 17, 2024
4G
Oct 17, 2024
4G
Oct 17, 2024
4G
Oct 17, 2024
2E
Oct 17, 2024
2E
Oct 17, 2024
2E
Oct 17, 2024
2E
Oct 17, 2024
4G
Oct 17, 2024
4G
Oct 17, 2024
71
Jul 1, 2019
Violation
Unknown
Violation
Unknown
Violation
Unknown
Violation
Unknown
Violation
Unknown
Violation
Unknown
Violation
Unknown
Violation
Unknown
Violation
Unknown
Violation
Unknown
Violation
Unknown
Violation
Unknown
Violation
Unknown
Resolved Violations (397)
52
Oct 1, 2024
52
Oct 1, 2024
52
Oct 1, 2024
52
Oct 1, 2024
52
Oct 1, 2024
+ 392 more resolved violations
Frequently Asked Questions
Is Napa tap water safe to drink?
Napa's water meets all EPA maximum contaminant levels. However, 0 contaminants were detected at various levels. Some residents may prefer additional filtration for peace of mind.
What contaminants are in Napa tap water?
0 contaminants have been detected in Napa's water supply across 18 water systems. See the full contaminant table above for details.
How can I improve my water quality in Napa?
Install a water filter rated for the specific contaminants found in Napa's water. See our filter recommendations above. You can also request your utility's Consumer Confidence Report for the most current test results.
Does Napa have any water quality violations?
Yes, Napa currently has 30 active violations. See the violations section above for details.