Los Altos, California Water Quality Report
Water quality data for 6 water systems serving 685 people.
Water Source
Detected Contaminants
No contaminant data available for this location.
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Compliance & Violations
Active Violations (20)
51
Jul 1, 1998
51
Jan 1, 1998
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
Violation
Unknown
Violation
Unknown
Violation
Unknown
Violation
Unknown
Violation
Unknown
Resolved Violations (233)
71
Jul 1, 2025
03
Jan 1, 2023 — Mar 31, 2023
03
Jan 1, 2023 — Mar 31, 2023
03
Jan 1, 2023 — Mar 31, 2023
03
Jan 1, 2023 — Mar 31, 2023
+ 228 more resolved violations
Frequently Asked Questions
Is Los Altos tap water safe to drink?
Los Altos'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 Los Altos tap water?
0 contaminants have been detected in Los Altos's water supply across 6 water systems. See the full contaminant table above for details.
How can I improve my water quality in Los Altos?
Install a water filter rated for the specific contaminants found in Los Altos's water. See our filter recommendations above. You can also request your utility's Consumer Confidence Report for the most current test results.
Does Los Altos have any water quality violations?
Yes, Los Altos currently has 20 active violations. See the violations section above for details.