Is there PFAS in North Wales Water Authority water?
Yes. EPA's final UCMR 5 results show North Wales Water Authority averaged 12.2 ppt of PFOA at its worst sampling point, 3.0 times the EPA limit of 4 ppt.
North Wales Water Authority
Serves 72,496 people · 16 PFOA samples from 7 sampling points · Aug 2024 to May 2025
Average above an EPA limit
PFOA Perfluorooctanoic acid
12.2 ppt avg · max 13.0
PFOS Perfluorooctanesulfonic acid
10.9 ppt avg · max 11.1
PFHxS Perfluorohexanesulfonic acid
3.7 ppt avg
PFNA Perfluorononanoic acid
2.8 ppt avg · max 5.6
Hazard index GenX, PFBS, PFNA, PFHxS combined
0.7 avg
Also detected, no federal limit: PFPeA, PFHxA, PFBA, PFBS, PFHpA.
North Wales Water Authority is a public water system drawing on surface water, based in North Wales, Pennsylvania, serving about 72,496 people, including Chalfont, Colmar, Montgomeryville, Warrington, Ambler, Fort Washington. Under EPA's Fifth Unregulated Contaminant Monitoring Rule it was tested for 29 PFAS and lithium 16 times across 7 sampling points between Aug 2024 and May 2025.
Every PFAS detected
Not detected: PFDA, PFEESA, PFMBA, PFMPA, 8:2 FTS, 4:2 FTS, 6:2 FTS, HFPO-DA, 9Cl-PF3ONS, PFUnA, NFDHA, PFDoA, ADONA, NMeFOSAA, NEtFOSAA, PFTrDA, PFTA, PFHpS, PFPeS, 11Cl-PF3OUdS.
Lithium, tested in the same program: highest 9.7 ppb, detected in 2 of 16 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 Pennsylvania
All 390 tested systems in Pennsylvania
ZIP codes served
18914 18915 18936 18976 19002 19034 19422 19436 19437 19440 19446 19454 19477 19486 19490
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 North Wales Water Authority water: EPA UCMR 5 results." Data: U.S. EPA Fifth Unregulated Contaminant Monitoring Rule, final release August 2026, PWSID PA1460048. https://wellandtap.com/pfas/pennsylvania/north-wales-water-authority/
About this data
Source: U.S. EPA, UCMR 5 occurrence data, final release August 2026 (PWSID PA1460048). Population: EPA SDWIS. Averages count results below the reporting level as zero, the same convention EPA uses for running annual averages. Full method.
