Is there PFAS in Cincinnati Public Water System water?
Yes. EPA's final UCMR 5 results show Cincinnati Public Water System averaged 5.2 ppt of PFOS at its worst sampling point, 1.3 times the EPA limit of 4 ppt.
Cincinnati Public Water System
Serves 750,200 people · 6 PFOA samples from 2 sampling points · May 2023 to Feb 2024
Average above an EPA limit
PFOA Perfluorooctanoic acid
not detected
PFOS Perfluorooctanesulfonic acid
5.2 ppt avg · max 6.1
Hazard index GenX, PFBS, PFNA, PFHxS combined
not detected
Also detected, no federal limit: PFBA, PFBS.
Cincinnati Public Water System is a public water system drawing on surface water, based in Cincinnati, Ohio, serving about 750,200 people, including Addyston, Cleves, Hamilton, Fairfield, Harrison, Mason. Under EPA's Fifth Unregulated Contaminant Monitoring Rule it was tested for 29 PFAS and lithium 6 times across 2 sampling points between May 2023 and Feb 2024.
Every PFAS detected
Not detected: PFHpA, 6:2 FTS, 4:2 FTS, 8:2 FTS, PFMPA, PFPeA, PFHpS, PFEESA, ADONA, NFDHA, NEtFOSAA, PFTrDA, NMeFOSAA, PFMBA, PFHxA, PFTA, PFNA, PFOA, PFDoA, HFPO-DA, PFUnA, PFHxS, 11Cl-PF3OUdS, 9Cl-PF3ONS, PFPeS, PFDA.
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
45001 45002 45013 45014 45030 45040 45041 45052 45069 45140 45174 45202 45203 45204 45205 45206 45207 45208 45209 45211 45212 45213 45214 45215 45216 45217 45218 45219 45220 45221 45223 45224 45225 45226 45227 45229 45230 45231 45232 45233 45236 45237 45238 45239 45240 45241 45242 45243 45244 45245 45246 45247 45248 45249 45251 45252 45255
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 Cincinnati Public Water System water: EPA UCMR 5 results." Data: U.S. EPA Fifth Unregulated Contaminant Monitoring Rule, final release August 2026, PWSID OH3102612. https://wellandtap.com/pfas/ohio/cincinnati-public-water-system/
About this data
Source: U.S. EPA, UCMR 5 occurrence data, final release August 2026 (PWSID OH3102612). Population: EPA SDWIS. Averages count results below the reporting level as zero, the same convention EPA uses for running annual averages. Full method.
