Johnston, Iowa Water Quality Report
Water quality data for 2 water systems serving 25,233 people.
Water Source
Detected Contaminants
| Contaminant | Detected Level | EPA Limit (MCL) | Health Guideline | % of Limit | Status |
|---|---|---|---|---|---|
| lithium | 33.0 | No federal limit | 10.0 ug/L(EPA/USGS HBSL) | 330% | Above guideline |
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Compliance & Violations
Active Violations (15)
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Resolved Violations (85)
03
Oct 1, 2024 — Sep 30, 2025
03
Oct 1, 2022 — Sep 30, 2025
03
Oct 1, 2019 — Sep 30, 2025
03
Oct 1, 2019 — Sep 30, 2025
03
Oct 1, 2019 — Sep 30, 2025
+ 80 more resolved violations
Frequently Asked Questions
Is Johnston tap water safe to drink?
Johnston'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 Johnston tap water?
1 contaminants have been detected in Johnston's water supply across 2 water systems. See the full contaminant table above for details.
How can I improve my water quality in Johnston?
Install a water filter rated for the specific contaminants found in Johnston's water. See our filter recommendations above. You can also request your utility's Consumer Confidence Report for the most current test results.
Does Johnston have any water quality violations?
Yes, Johnston currently has 15 active violations. See the violations section above for details.