Lake Oswego, Oregon Water Quality Report
Water quality data for 8 water systems serving 48,044 people.
Water Source
Detected Contaminants
| Contaminant | Detected Level | EPA Limit (MCL) | Health Guideline | % of Limit | Status |
|---|---|---|---|---|---|
| lithium | 12.0 | No federal limit | 10.0 ug/L(EPA/USGS HBSL) | 120% | Above guideline |
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Compliance & Violations
Resolved Violations (500)
71
Jul 1, 2025
71
Jul 1, 2025
71
Jul 1, 2025
72
Oct 1, 2024
52
Oct 1, 2024
+ 495 more resolved violations
Frequently Asked Questions
Is Lake Oswego tap water safe to drink?
Lake Oswego's water meets all EPA maximum contaminant levels. However, 1 contaminants were detected at various levels. Some residents may prefer additional filtration for peace of mind.
What contaminants are in Lake Oswego tap water?
1 contaminants have been detected in Lake Oswego's water supply across 8 water systems. See the full contaminant table above for details.
How can I improve my water quality in Lake Oswego?
Install a water filter rated for the specific contaminants found in Lake Oswego's water. See our filter recommendations above. You can also request your utility's Consumer Confidence Report for the most current test results.
Does Lake Oswego have any water quality violations?
Yes, Lake Oswego currently has 23 active violations. See the violations section above for details.