EPA UCMR 5 · 2023–2025 monitoring
PFAS in Ohio drinking water
EPA tested 316 public water systems in Ohio for PFAS under UCMR 5. 130 of them had at least one detection, a rate of 41.1%, which is 12th highest of the 51 states and territories with comparable testing. Systems with a detection serve roughly 5,418,692 people in Ohio.
Ohio systems with the highest PFAS results
Highest single compound result recorded at each system during UCMR 5 monitoring.
| Water system | Population served | Highest result |
|---|---|---|
| Newton Falls City | 6,109 | 220 ppt |
| Ottawa Village | 4,393 | 90.4 ppt |
| Bluffton Village | 4,125 | 42 ppt |
| Sanitary District #4 | 8,575 | 22 ppt |
| Mcdonald Village Pws | 4,236 | 21.2 ppt |
Which PFAS compounds were found in Ohio?
The compounds detected most often across Ohio systems were: PFBA (58 systems), PFPeA (47 systems), PFBS (46 systems), PFHxA (34 systems). Only five PFAS currently carry enforceable federal limits, phased in through 2029 (EPA on PFAS risk). Several of the most commonly detected compounds, including PFPeA and PFBA, have no federal limit at all, which is why a system can be fully compliant and still show detections.
What about lead in Ohio?
Across the 148 Ohio systems serving 10,000 people or more, the median lead 90th-percentile result is 0.7 ppb. The federal action level is 15 ppb, but that is a trigger for utility action rather than a health threshold: no level of lead exposure is considered safe. Lead almost always enters through service lines and household plumbing rather than the treatment plant, so a low statewide median tells you about the systems, not about your building.
How often do Ohio systems break drinking water law?
Across 1,048 active community water systems in Ohio, 215 have recorded at least one health-based Safe Drinking Water Act violation since 2020, a rate of 20.5 percent. Those systems serve about 1,450,851 people. Nationally the equivalent figure is 58.8 million.
A health-based violation means a contaminant exceeded a legal limit or required treatment was not delivered, as distinct from a missed sampling deadline. Small rural systems dominate these counts everywhere: one operator, no treatment budget, and a few hundred customers. Read it as a picture of a state's smallest utilities more than of its cities. Full national analysis.
Is Ohio tap water safe to drink?
On the PFAS measure specifically, 41.1 percent of tested Ohio systems recorded a detection, against a national picture where about a third of tested systems did. That is a statement about the state, not about your tap: within any state, results vary enormously between systems drawing from different sources. The only figure that describes your water is your own utility's, which is why we would rather send you to look it up than have you act on a state average.
For what these compounds are understood to do in the body, see ATSDR on PFAS health effects. One rule worth carrying: a system with no UCMR 5 record has not been shown to be clean. It has not been tested. We never label an untested system as PFAS-free, and neither should anyone else.
Ohio cities we score in detail
Full contaminant breakdowns, with every figure cited:
How does your own system compare?
Fifty of the largest US water systems, scored against health guidance, every figure linked to its source.