Also detected, no federal limit: PFBS, PFHxA, PFPeA.
Is there PFAS in Foxboro Water Department water?
Yes. EPA's final UCMR 5 results show Foxboro Water Department averaged 6.4 ppt of PFOS at its worst sampling point, 1.6 times the EPA limit of 4 ppt.
Foxboro Water Department is a public water system drawing on groundwater, based in Foxborough, Massachusetts, serving about 18,721 people. Under EPA's Fifth Unregulated Contaminant Monitoring Rule it was tested for 29 PFAS and lithium 6 times across 3 sampling points between Feb 2025 and Sep 2025.
Every PFAS detected
| PFAS | Detected | Highest | Worst point avg | EPA limit |
|---|---|---|---|---|
| PFOS Perfluorooctanesulfonic acid |
6 of 6 | 6.7 ppt | 6.4 ppt | 4 ppt |
| PFOA Perfluorooctanoic acid |
5 of 6 | 6.3 ppt | 5.8 ppt | 4 ppt |
| PFBS Perfluorobutanesulfonic acid |
4 of 6 | 4.6 ppt | 4.3 ppt | none |
| PFHxA Perfluorohexanoic acid |
1 of 6 | 4.0 ppt | 2.0 ppt | none |
| PFPeA Perfluoropentanoic acid |
1 of 6 | 3.7 ppt | 1.9 ppt | none |
Not detected: PFDA, 11Cl-PF3OUdS, PFUnA, PFDoA, 9Cl-PF3ONS, ADONA, PFHxS, PFMPA, PFHpA, PFNA, PFMBA, NMeFOSAA, NEtFOSAA, PFTrDA, PFTA, PFHpS, PFPeS, 4:2 FTS, PFEESA, HFPO-DA, 8:2 FTS, 6:2 FTS, PFBA, NFDHA.
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 Massachusetts
- Concord Water Dept above an EPA limit
- Ashland Water & Sewer Dept. 1 PFAS detected
- Westford Water Department above an EPA limit
- Sudbury Water District above an EPA limit
- Somerset Water Department none detected
- Norton Water Department above an EPA limit
All 263 tested systems in Massachusetts
ZIP codes served
02035
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 Foxboro Water Department water: EPA UCMR 5 results." Data: U.S. EPA Fifth Unregulated Contaminant Monitoring Rule, final release August 2026, PWSID MA4099000. https://wellandtap.com/pfas/massachusetts/foxboro-water-department/
About this data
Source: U.S. EPA, UCMR 5 occurrence data, final release August 2026 (PWSID MA4099000). Population: EPA SDWIS. Averages count results below the reporting level as zero, the same convention EPA uses for running annual averages. Full method.