Lewiston, Idaho Water Quality Report
Water quality data for 9 water systems serving 36,074 people.
Water Source
Detected Contaminants
| Contaminant | Detected Level | EPA Limit (MCL) | Health Guideline | % of Limit | Status |
|---|---|---|---|---|---|
| lithium | 43.8 | No federal limit | 10.0 ug/L(EPA/USGS HBSL) | 438% | Above guideline |
| PFBS | 0.006 | No federal limit | 2000.0 ug/L(EPA Health Advisory) | 0% | Below guideline |
| PFHxA | 0.004 | No federal limit | 1000.0 ug/L(EWG) | 0% | Below guideline |
| PFPeA | 0.005 | No federal limit | 1000.0 ug/L(EWG) | 0% | Below guideline |
Recommended Water Filters
Based on the contaminants detected in your water supply, these filtration systems are recommended:
Reverse Osmosis (RO)
Reverse osmosis systems remove up to 99% of PFAS compounds. Recommended for homes with detected PFAS.
Up to 99% PFAS removal
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Compliance & Violations
Active Violations (34)
20
Jul 19, 2025
20
Jul 19, 2025
75
Jan 3, 2025
75
Jan 3, 2025
75
Jan 3, 2025
75
Jan 3, 2025
66
Dec 30, 2024
66
Dec 30, 2024
66
Dec 30, 2023
66
Dec 30, 2023
66
Dec 30, 2022
66
Dec 30, 2022
66
Dec 30, 2022
66
Dec 30, 2022
66
Dec 30, 2021
66
Dec 30, 2021
66
Dec 30, 2020
66
Dec 30, 2020
75
Dec 28, 2018
75
Dec 28, 2018
75
Dec 28, 2018
75
Dec 28, 2018
75
Dec 28, 2018
75
Dec 28, 2018
75
Dec 28, 2018
75
Dec 28, 2018
75
Dec 28, 2018
75
Dec 28, 2018
75
Dec 28, 2018
75
Dec 28, 2018
75
Dec 28, 2018
75
Dec 28, 2018
75
Dec 28, 2018
75
Dec 28, 2018
Resolved Violations (466)
2E
Oct 17, 2024
2E
Oct 17, 2024
4G
Oct 17, 2024
4G
Oct 17, 2024
4G
Oct 17, 2024
+ 461 more resolved violations
Frequently Asked Questions
Is Lewiston tap water safe to drink?
Lewiston's water meets all EPA maximum contaminant levels. However, 4 contaminants were detected at various levels. Some residents may prefer additional filtration for peace of mind.
What contaminants are in Lewiston tap water?
4 contaminants have been detected in Lewiston's water supply across 9 water systems. See the full contaminant table above for details.
How can I improve my water quality in Lewiston?
Install a water filter rated for the specific contaminants found in Lewiston's water. See our filter recommendations above. You can also request your utility's Consumer Confidence Report for the most current test results.
Does Lewiston have any water quality violations?
Yes, Lewiston currently has 64 active violations. See the violations section above for details.