Connecticut tap water, by utility.

63 utilities with a full report, serving 2.7 million people as they report it. Regulated PFAS turned up at 38 of them.

Connecticut utilities by population served
Utility	Based in	Serves	Regulated PFAS	Health-based violations since 2016
Regional Water Authority	Ansonia	418,900	PFOA, PFOS, PFBS	0
Metropolitan District Commission	South Windsor	390,887	None found	0
Aquarion - Eastern Fairfield County	Beacon Falls	351,756	PFOA, PFOS, PFBS	0
Aquarion - Stamford	Darien	119,214	PFOA	0
Waterbury Water Department	Middlebury	107,271	None found	0
Ctwc - Northern Reg - Western System	East Granby	101,313	PFOA, PFOS, PFHxS, PFBS	0
New Britain Water Department	Berlin	73,534	None found	0
Danbury Water Department	Bethel	62,055	PFOA, PFBS	1
Meriden Water Division	Berlin	58,441	PFOA, PFOS, PFHxS, PFBS	1
Aquarion - Greenwich	Greenwich	53,297	PFOA, PFOS	0
Bristol Water Department	Bristol	52,079	PFOA	0
Manchester Water Department	Glastonbury	51,198	PFOA, PFOS, PFHxS, PFBS	0
Southington Water Department	Cheshire	43,069	PFOA, PFOS, PFBS	0
South Norwalk Electric & Water	Darien	42,000	None found	3
Middletown Water Department	Cromwell	41,019	None found	0
Norwalk First Taxing District	New Canaan	40,256	PFOA, PFOS, PFHxS, PFBS	0
Torrington Water Company	Harwinton	37,915	None found	1
Wallingford Water Department	North Haven	37,267	PFOS, PFHxS, PFBS	0
Norwich Public Utilities	Franklin	36,163	PFOA, PFOS, PFHxS, PFBS	9
Ctwc - Shoreline Region - Guilford System	Clinton	33,975	PFOA, PFOS, PFHxS, PFBS	0
Mohegan Tribal Utility Authority	Uncasville	31,961	None found	1
Groton Utilities	Groton	30,200	None found	0
New London Dept. of Public Utilities	New London	27,620	None found	0
University of Connecticut - Main Campus	Mansfield	27,199	PFOS	0
Ctwc - Naugatuck Region - Central System	Beacon Falls	22,735	None found	0
Mashantucket Pequot Water System	Mashantucket	22,171	PFOA, PFBS	2
Windham Water Works	Mansfield	21,214	None found	0
Aquarion - Darien	Darien	18,737	PFOA	0
Hazardville Water Company	East Windsor	18,544	PFOA, PFOS, PFHxS, PFBS	0
Aquarion - Plainville Regional	Bristol	18,231	PFOA, PFOS	1
Waterford Wpca	Montville	16,578	None found	0
East Lyme Water & Sewer Commission	East Lyme	15,245	PFOA, PFOS, PFBS	0
Ctwc - Unionville System	Avon	14,693	PFOA, PFOS, PFHxS	2
Aquarion - Simsbury Regional	East Granby	14,691	PFOA, PFOS, PFHxS	0
Cromwell Fire District Water Department	Berlin	14,316	PFOS, PFHxS	0
Aquarion - New Milford Regional	Brookfield	13,331	PFOA, PFOS, PFBS	0
Aquarion - Valley	Ansonia	13,080	PFOA, PFOS, PFBS	0
Avon Water Co	Avon	11,590	PFOA, PFOS, PFBS	0
Aquarion - Mystic	Groton	10,788	PFBS	0
Aquarion - New Canaan	New Canaan	10,097	PFOA	0
Watertown Water & Sewer Authority	Middlebury	9,972	None found	0
Bethel Water Dept	Bethel	9,507	PFOA, PFBS	2
Winsted Water Works	Barkhamsted	7,784	None found	0
Kensington Fire District	Berlin	7,553	None found	0
Aquarion - Ridgefield	Ridgefield	7,476	PFOA, PFOS, PFBS	0
Putnam Water Pollution Control Authority	Putnam	7,300	PFOA, PFOS, PFHxS, PFBS	0
Heritage Water Company	Middlebury	7,300	PFOA, PFBS	0
Jewett City Water Company	Griswold	6,840	None found	1
Watertown Fire District	Watertown	6,718	None found	0
Ctwc - Crystal System	Brooklyn	6,378	PFOA, PFOS, PFHxS, PFBS	0
Ctwc - Naugatuck Reg - Collinsville Sys	Avon	6,324	PFOA, PFOS	0
Aquarion - Newtown Regional	Newtown	6,054	PFOA, PFOS, PFHxS, PFBS	0
Ctwc - Naugatuck Reg - Terryville System	Plymouth	5,607	None found	0
Berlin Water Control Commission	Berlin	5,128	PFHxS	1
Ctwc - Shoreline Region - Chester System	Chester	5,030	None found	0
Portland Water Department	Middletown	5,010	None found	0
Colchester Sewer & Water Commission	Colchester	4,020	PFOS, PFHxS	0
Ctwc - Naugatuck Reg - Thomaston System	Plymouth	3,789	None found	0
Ctwc - Shoreline Region - Sound View	Old Lyme	3,397	Not sampled	0
Aquarion - Litchfield Regional	Goshen	3,097	None found	0
Aquarion - New Hartford	New Hartford	1,872	None found	0
Ctwc - Coventry Hills Div	Coventry	700	None found	0
Aquarion - Woodrich Village	Wolcott	72	PFOA, PFOS, PFBS	0
Utilities EPA sampled under UCMR 5, plus any other community system serving 3,300 people or more. Smaller systems appear in ZIP code results. Data: EPA SDWIS 2026 Q2 and UCMR 5.