Is there PFAS in Dayton Public Water System water?
Some. At least one sample reached an EPA limit, but the average at every sampling point stayed below it.
Dayton Public Water System
Serves 141,407 people · 8 PFOA samples from 1 sampling point · Mar 2023 to Dec 2023
One or more samples at an EPA limit
PFOA Perfluorooctanoic acid
not detected
PFOS Perfluorooctanesulfonic acid
3.8 ppt avg · max 10.0
PFHxS Perfluorohexanesulfonic acid
4.2 ppt avg · max 9.8
Hazard index GenX, PFBS, PFNA, PFHxS combined
0.4 avg · max 1.0
Also detected, no federal limit: PFPeA, PFHxA, PFBS.
Dayton Public Water System is a public water system drawing on surface water, based in Dayton, Ohio, serving about 141,407 people, including Clayton, Englewood, Vandalia, Dayton. Under EPA's Fifth Unregulated Contaminant Monitoring Rule it was tested for 29 PFAS and lithium 8 times across 1 sampling point between Mar 2023 and Dec 2023.
Every PFAS detected
Not detected: PFTA, PFOA, PFMPA, PFMBA, PFHpS, PFUnA, NEtFOSAA, PFPeS, PFTrDA, PFNA, ADONA, PFHpA, NFDHA, 8:2 FTS, 6:2 FTS, NMeFOSAA, HFPO-DA, PFEESA, 9Cl-PF3ONS, 11Cl-PF3OUdS, PFDoA, PFDA, PFBA, 4:2 FTS.
Lithium, tested in the same program: not detected.
What the EPA limits mean here
In April 2024 EPA set enforceable limits of 4 ppt for PFOA and PFOS, 10 ppt each for PFHxS, PFNA and GenX, and a hazard index of 1 for mixtures. Utilities were given until 2029 to comply. In May 2026 EPA proposed keeping only the PFOA and PFOS limits and moving that deadline to 2031. Until that proposal is final, the 2024 limits stand.
Compliance is judged on a running annual average at each entry point, so we show the average at this system's worst sampling point next to its single highest result. UCMR 5 results do not by themselves put a utility in or out of compliance.
What you can do at home
Two routes work for PFAS. For drinking and cooking water only, a reverse osmosis system certified to NSF/ANSI 58 with a PFOA/PFOS reduction claim is the cheapest proven option. To treat every tap and shower, a whole-house carbon system with enough contact time works, but check that the maker has PFAS test data, not just a marketing claim. See the best filters for PFAS and how PFAS removal works.
Other systems in Ohio
All 347 tested systems in Ohio
ZIP codes served
45315 45322 45377 45402 45403 45404 45405 45406 45408 45409 45410 45414 45415 45416 45417 45419 45420 45424 45426 45427 45428 45431 45432 45439
As reported by the utility to EPA. Neighbouring ZIPs are often split between systems; your water bill names yours.
Cite this page
Well & Tap. "PFAS in Dayton Public Water System water: EPA UCMR 5 results." Data: U.S. EPA Fifth Unregulated Contaminant Monitoring Rule, final release August 2026, PWSID OH5703512. https://wellandtap.com/pfas/ohio/dayton-public-water-system/
About this data
Source: U.S. EPA, UCMR 5 occurrence data, final release August 2026 (PWSID OH5703512). Population: EPA SDWIS. Averages count results below the reporting level as zero, the same convention EPA uses for running annual averages. Full method.
