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Is there PFAS in Waterloo Water Works water?

Yes. EPA's final UCMR 5 results show Waterloo Water Works averaged 11.4 ppt of PFHxS at its worst sampling point, 1.1 times the EPA limit of 10 ppt.

Waterloo Water Works Serves 69,504 people · 18 PFOA samples from 9 sampling points · Feb 2023 to Sep 2024 Average above an EPA limit
PFOA Perfluorooctanoic acid not detected
EPA 4
PFOS Perfluorooctanesulfonic acid not detected
EPA 4
PFHxS Perfluorohexanesulfonic acid 11.4 ppt avg · max 13.0
EPA 10
Hazard index GenX, PFBS, PFNA, PFHxS combined 1.1 avg · max 1.3
EPA 1

Also detected, no federal limit: PFPeA, PFBS, PFHxA.

Averages are for the worst sampling point, with non-detects counted as zero. Source: EPA UCMR 5.

Waterloo Water Works is a public water system drawing on groundwater, based in Waterloo, Iowa, serving about 69,504 people, including Waterloo, Evansdale. Under EPA's Fifth Unregulated Contaminant Monitoring Rule it was tested for 29 PFAS and lithium 18 times across 9 sampling points between Feb 2023 and Sep 2024.

Every PFAS detected

PFAS Detected Highest Worst point avg EPA limit
PFHxS
Perfluorohexanesulfonic acid
4 of 18 13.0 ppt 11.4 ppt 10 ppt
PFPeA
Perfluoropentanoic acid
2 of 18 4.8 ppt 4.5 ppt none
PFBS
Perfluorobutanesulfonic acid
2 of 18 3.2 ppt 3.2 ppt none
PFHxA
Perfluorohexanoic acid
1 of 18 3.1 ppt 1.6 ppt none

Not detected: PFDA, PFOA, PFOS, PFNA, PFEESA, PFHpA, PFHpS, PFPeS, NFDHA, PFDoA, PFMBA, 11Cl-PF3OUdS, 9Cl-PF3ONS, ADONA, HFPO-DA, PFBA, PFUnA, 6:2 FTS, 4:2 FTS, 8:2 FTS, PFMPA, NMeFOSAA, NEtFOSAA, PFTA, PFTrDA.

Lithium, tested in the same program: highest 20 ppb, detected in 10 of 18 samples. EPA's health-based screening level is 10 ppb.

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 Iowa

All 152 tested systems in Iowa

ZIP codes served

50701 50702 50703 50704 50706 50707

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 Waterloo Water Works water: EPA UCMR 5 results." Data: U.S. EPA Fifth Unregulated Contaminant Monitoring Rule, final release August 2026, PWSID IA0790074. https://wellandtap.com/pfas/iowa/waterloo-water-works/

About this data

Source: U.S. EPA, UCMR 5 occurrence data, final release August 2026 (PWSID IA0790074). Population: EPA SDWIS. Averages count results below the reporting level as zero, the same convention EPA uses for running annual averages. Full method.