Is there PFAS in Ctwc - Shoreline Region-guilford System water?

Some. At least one sample reached an EPA limit, but the average at every sampling point stayed below it.

Ctwc - Shoreline Region-guilford System is a public water system drawing on surface water, based in Clinton, Connecticut, serving about 33,975 people, including Clinton, Guilford, Madison, Old Saybrook, Westbrook. Under EPA's Fifth Unregulated Contaminant Monitoring Rule it was tested for 29 PFAS and lithium 22 times across 2 sampling points between Mar 2024 and Sep 2025.

Every PFAS detected

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

• Norwich Public Utilities 5 PFAS detected
• Wallingford Water Department 3 PFAS detected
• Groton Utilities none detected
• Torrington Water Company none detected
• Norwalk First Taxing District above an EPA limit
• New London Dept. of Public Utilities none detected

All 63 tested systems in Connecticut

ZIP codes served

06413 06437 06443 06475 06498

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 Ctwc - Shoreline Region-guilford System water: EPA UCMR 5 results." Data: U.S. EPA Fifth Unregulated Contaminant Monitoring Rule, final release August 2026, PWSID CT0608011. https://wellandtap.com/pfas/connecticut/ctwc-shoreline-region-guilford-system/

About this data

Source: U.S. EPA, UCMR 5 occurrence data, final release August 2026 (PWSID CT0608011). Population: EPA SDWIS. Averages count results below the reporting level as zero, the same convention EPA uses for running annual averages. Full method.