Ontario, Oregon Water Quality Report
Water quality data for 2 water systems serving 14,555 people.
Water Source
Detected Contaminants
| Contaminant | Detected Level | EPA Limit (MCL) | Health Guideline | % of Limit | Status |
|---|---|---|---|---|---|
| lithium | 38.4 | No federal limit | 10.0 ug/L(EPA/USGS HBSL) | 384% | Above guideline |
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Compliance & Violations
Active Violations (12)
71
Jul 1, 2025
Violation
Unknown
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Unknown
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Unknown
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Unknown
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Unknown
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Unknown
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Unknown
Resolved Violations (199)
71
Jul 1, 2024
36
Mar 1, 2023 — Mar 31, 2023
38
Mar 1, 2023 — Mar 31, 2023
36
Mar 1, 2023 — Mar 31, 2023
36
Mar 1, 2023 — Mar 31, 2023
+ 194 more resolved violations
Frequently Asked Questions
Is Ontario tap water safe to drink?
Ontario'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 Ontario tap water?
1 contaminants have been detected in Ontario's water supply across 2 water systems. See the full contaminant table above for details.
How can I improve my water quality in Ontario?
Install a water filter rated for the specific contaminants found in Ontario's water. See our filter recommendations above. You can also request your utility's Consumer Confidence Report for the most current test results.
Does Ontario have any water quality violations?
Yes, Ontario currently has 12 active violations. See the violations section above for details.