Is JOHNSTON MUNICIPAL WATER SUPPLY's water safe to drink?
JOHNSTON MUNICIPAL WATER SUPPLY has a health-based violation on record, but none in the last five years - an older issue, not necessarily a current one. It serves 24,897 people through 7,657 service connections.
How this compares nationally
5 total violations and 1 health-based ones put JOHNSTON MUNICIPAL WATER SUPPLY at the 33th percentile nationally for violation burden, rank 8,678 of 12,903.
How JOHNSTON MUNICIPAL WATER SUPPLY compares within IA
JOHNSTON MUNICIPAL WATER SUPPLY's 1 health-based violations sit within the IA average of 3.5, across 203 systems statewide. The filter guide explains what a violation like this actually calls for.
Most recent violation on record
The last violation EPA has on record for JOHNSTON MUNICIPAL WATER SUPPLY is from 2013-01-05 (health-based: 2013-01-05). Last reported to EPA: 06/17/2026.
What kind of problem, specifically
JOHNSTON MUNICIPAL WATER SUPPLY's flagged contaminants and rule violations, grouped by what they actually mean for a filter choice rather than left as EPA's raw code list:
- Microbial contamination / treatment technique - flagged from: Coliform (TCR)
The most severe category on record is microbial contamination / treatment technique, which points toward a microbial-class filter if you want to address it directly.
What this data is and is not
This is what JOHNSTON MUNICIPAL WATER SUPPLY reported to its state primacy agency and EPA under the Safe Drinking Water Act - real regulatory record, not a lab test of your specific tap. Between the utility's meter and JOHNSTON MUNICIPAL WATER SUPPLY's customers' taps is household plumbing, invisible to a system-level record ranked 8,678th of 12,903 by violation count. The guide to what this data misses covers that gap.