Yes, at low levels. 1 PFAS was detected, all below EPA's 2024 limits.
Also detected, no federal limit: PFBA.
Rathbun Reg Water Assn (ft Madison) is a public water system drawing on surface water, based in Centerville, Iowa, serving about 11,840 people, including Burlington, Argyle, Bonaparte, Danville, Denmark, Donnellson. Under EPA's Fifth Unregulated Contaminant Monitoring Rule it was tested for 29 PFAS and lithium 5 times across 2 sampling points between Dec 2023 and Sep 2024.
| PFAS | Detected | Highest | Worst point avg | EPA limit |
|---|---|---|---|---|
| PFBA Perfluorobutanoic acid |
2 of 5 | 12.0 ppt | 7.7 ppt | none |
Not detected: PFOS, ADONA, 9Cl-PF3ONS, 11Cl-PF3OUdS, PFUnA, PFHxA, PFDoA, HFPO-DA, PFOA, 8:2 FTS, PFHxS, PFHpA, PFBS, PFNA, PFDA, 4:2 FTS, PFMPA, PFPeA, PFMBA, PFEESA, NFDHA, PFPeS, PFHpS, PFTrDA, NEtFOSAA, NMeFOSAA, PFTA, 6:2 FTS.
Lithium, tested in the same program: highest 16 ppb, detected in 2 of 6 samples. EPA's health-based screening level is 10 ppb.
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.
Levels here are under EPA's limits, so no treatment is required. If you want them lower anyway, a certified reverse osmosis system under the sink handles drinking water, and a whole-house carbon filter also takes out the chlorine or chloramine your utility adds.
All 152 tested systems in Iowa
52601 52619 52620 52623 52624 52625 52626 52627 52630 52631 52632 52639 52645 52649 52656 52657 52658 62341 62354 62358 62379 63430 63465
As reported by the utility to EPA. Neighbouring ZIPs are often split between systems; your water bill names yours.
Well & Tap. "PFAS in Rathbun Reg Water Assn (ft Madison) water: EPA UCMR 5 results." Data: U.S. EPA Fifth Unregulated Contaminant Monitoring Rule, final release August 2026, PWSID IA0400901. https://wellandtap.com/pfas/iowa/rathbun-reg-water-assn-ft-madison/
Source: U.S. EPA, UCMR 5 occurrence data, final release August 2026 (PWSID IA0400901). Population: EPA SDWIS. Averages count results below the reporting level as zero, the same convention EPA uses for running annual averages. Full method.
