Is there PFAS in Suffolk County Water Authority water?
Yes. EPA's final UCMR 5 results show Suffolk County Water Authority averaged 12.1 ppt of PFOS at its worst sampling point, 3.0 times the EPA limit of 4 ppt.
Suffolk County Water Authority
Serves 1.1 million people · 480 PFOA samples from 242 sampling points · Jan 2023 to Sep 2025
Average above an EPA limit
PFOA Perfluorooctanoic acid
6.0 ppt avg · max 6.5
PFOS Perfluorooctanesulfonic acid
12.1 ppt avg · max 17.4
PFHxS Perfluorohexanesulfonic acid
6.8 ppt avg · max 10.8
PFNA Perfluorononanoic acid
5.0 ppt avg · max 5.7
Hazard index GenX, PFBS, PFNA, PFHxS combined
1.2 avg
Also detected, no federal limit: PFHxA, PFPeA, 6:2 FTS, PFBA, PFHpA, PFBS.
Suffolk County Water Authority is a public water system drawing on groundwater, based in Hauppauge, New York, serving about 1.1 million people, including Amityville, Babylon, North Babylon, West Babylon, Bayport, Bay Shore. Under EPA's Fifth Unregulated Contaminant Monitoring Rule it was tested for 29 PFAS and lithium 480 times across 242 sampling points between Jan 2023 and Sep 2025.
Every PFAS detected
Not detected: PFMBA, ADONA, HFPO-DA, 4:2 FTS, 8:2 FTS, PFTrDA, NMeFOSAA, PFMPA, NEtFOSAA, PFDA, PFTA, PFHpS, PFPeS, NFDHA, PFEESA, 9Cl-PF3ONS, 11Cl-PF3OUdS, PFUnA, PFDoA.
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 New York
All 334 tested systems in New York
ZIP codes served
11701 11702 11703 11704 11705 11706 11713 11716 11717 11719 11720 11721 11722 11724 11725 11726 11727 11729 11730 11731 11733 11735 11738 11741 11742 11743 11746 11749 11751 11752 11754 11755 11757 11763 11764 11766 11767 11768 11769 11770 11772 11776 11777 11778 11779 11780 11782 11784 11786 11787 11788 11790 11795 11798 11901 11934 11935 11937 11939 11941 11942 11944 11949 11950 11952 11953 11954 11957 11958 11961 11963 11964 11965 11967 11968 11971 11976 11978 11980
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 Suffolk County Water Authority water: EPA UCMR 5 results." Data: U.S. EPA Fifth Unregulated Contaminant Monitoring Rule, final release August 2026, PWSID NY5110526. https://wellandtap.com/pfas/new-york/suffolk-county-water-authority/
About this data
Source: U.S. EPA, UCMR 5 occurrence data, final release August 2026 (PWSID NY5110526). Population: EPA SDWIS. Averages count results below the reporting level as zero, the same convention EPA uses for running annual averages. Full method.
