PFAS Contamination

PFAS in Connecticut Drinking Water

Ranked by number of PFAS compounds detected · Data from EPA SDWIS & UCMR

105

Cities Tested

Exceeds Limit

75%

% Exceeds Limit

4.7 compounds

State Avg

▲ 54% vs national

vs National

105

Health Violations

Analysis

PFAS in Connecticut: what the data shows

Connecticut has 105 cities with PFAS monitoring data from the EPA's UCMR 5 program. PFAS ("forever chemicals") were detected in 86 of those cities (82%), with many cities exceeding the EPA's 2024 maximum contaminant levels of 4 ppt. The state average is worse than the national average. 79 cities exceed the EPA MCL for at least one PFAS compound. PFAS are linked to cancer, immune system disruption, and developmental issues. The 2024 EPA rule requires water systems exceeding the MCL to notify customers and reduce levels by 2029. PFAS data comes from the EPA's Unregulated Contaminant Monitoring Rule 5 (UCMR 5), which required large water systems to test for 29 PFAS compounds between 2023–2025. Not all systems have completed testing — cities without data may still have PFAS present.

Comparison

Cities exceeding EPA MCL (4 ppt each)

Connecticut

75%

79 of 105 cities

→ ▲ 54% above national rate (worse)

National avg

21%

1636 of 7745 cities

City Map

PFAS data across Connecticut

Each dot is a city, colored by overall water quality grade. PFAS-tested cities are shown; those exceeding the 4 ppt EPA MCL appear in red. Size reflects population served.

Worst Offenders

Top 10 cities by pfas level in Connecticut

Highest PFAS levels (compounds)

All Cities

All Connecticut cities ranked by pfas level

#	City	Level	Exceeds?	Violations	Grade
1	Cheshire	9 compounds	Yes	28	F
2	South Windsor	9 compounds	Yes	5	C
3	Manchester	9 compounds	Yes	8	C
4	Southington	9 compounds	Yes	12	F
5	Farmington	8 compounds	Yes	3	D+
6	Windsor Locks	8 compounds	Yes	0	B-
7	New Canaan	8 compounds	Yes	7	F
8	Westport	8 compounds	Yes	2	C-
9	East Windsor	8 compounds	Yes	25	F
10	Ellington	8 compounds	Yes	0	B
11	Suffield	8 compounds	Yes	1	C+
12	Wilton	8 compounds	Yes	7	D
13	Norwalk	8 compounds	Yes	7	D
14	Mansfield	8 compounds	Yes	85	F
15	Enfield	8 compounds	Yes	9	D
16	Newtown	8 compounds	Yes	46	F
17	Wolcott	8 compounds	Yes	18	F
18	Tolland	8 compounds	Yes	24	F
19	Stafford	8 compounds	Yes	12	C
20	Seymour	7 compounds	Yes	2	D+
21	Glastonbury	7 compounds	Yes	4	B+
22	Beacon Falls	7 compounds	Yes	3	C-
23	Bridgeport	7 compounds	Yes	2	C-
24	Darien	7 compounds	Yes	7	F
25	Fairfield	7 compounds	Yes	2	C-
26	Redding	7 compounds	Yes	2	C-
27	Shelton	7 compounds	Yes	2	C-
28	Stamford	7 compounds	Yes	4	F
29	Stratford	7 compounds	Yes	2	C-
30	Plainville	7 compounds	Yes	4	C
31	Meriden	7 compounds	Yes	4	C+
32	Bristol	7 compounds	Yes	4	C+
33	Wallingford	7 compounds	Yes	4	D
34	Clinton	7 compounds	Yes	4	D+
35	Guilford	7 compounds	Yes	20	D
36	Madison	7 compounds	Yes	18	C+
37	Old Saybrook	7 compounds	Yes	0	B-
38	Westbrook	7 compounds	Yes	7	C+
39	Avon	7 compounds	Yes	3	C+
40	Berlin	7 compounds	Yes	6	F
41	Greenwich	7 compounds	Yes	5	F
42	Ansonia	6 compounds	Yes	0	B+
43	Bethany	6 compounds	Yes	4	C-
44	Woodbridge	6 compounds	Yes	0	B+
45	Lisbon	6 compounds	Yes	27	F
46	Hampton	6 compounds	Yes	1	B
47	Mashantucket	6 compounds	Yes	7	B
48	Somers	6 compounds	Yes	6	C+
49	East Lyme	6 compounds	Yes	6	C
50	Oxford	6 compounds	Yes	6	B
51	North Haven	5 compounds	Yes	0	C-
52	Bozrah	5 compounds	Yes	13	B
53	Franklin	5 compounds	Yes	13	B
54	Montville	5 compounds	Yes	143	F
55	Norwich	5 compounds	Yes	19	B-
56	Preston	5 compounds	Yes	23	D+
57	Putnam	5 compounds	Yes	19	D
58	Granby	5 compounds	Yes	3	C+
59	New Milford	5 compounds	Yes	85	F
60	Brookfield	5 compounds	Yes	135	F
61	Woodstock	5 compounds	Yes	120	F
62	Branford	4 compounds	Yes	0	A-
63	Derby	4 compounds	Yes	0	B+
64	East Haven	4 compounds	Yes	0	A-
65	Hamden	4 compounds	Yes	0	A-
66	Milford	4 compounds	Yes	0	B+
67	New Haven	4 compounds	Yes	0	A-
68	North Branford	4 compounds	Yes	25	F
69	Orange	4 compounds	Yes	0	B+
70	Prospect	4 compounds	Yes	1	C+
71	West Haven	4 compounds	Yes	0	B+
72	Danbury	4 compounds	Yes	59	F
73	Bethel	4 compounds	Yes	25	F
74	Brooklyn	4 compounds	Yes	14	C-
75	Killingly	4 compounds	Yes	32	F
76	Middletown	3 compounds	No	11	D
77	Plymouth	2 compounds	Yes	18	C
78	Cromwell	2 compounds	Yes	1	B
79	Portland	2 compounds	No	9	C
80	Colchester	2 compounds	Yes	34	D
81	Southbury	2 compounds	Yes	15	D
82	Newington	1 compounds	No	1	D
83	Groton	1 compounds	No	17	F
84	Stonington	1 compounds	No	6	B
85	Griswold	1 compounds	No	53	F
86	Ledyard	1 compounds	No	23	D+
87	East Hartford	0 compounds	No	0	A-
88	Hartford	0 compounds	No	0	A-
89	Rocky Hill	0 compounds	No	1	B
90	West Hartford	0 compounds	No	0	B+
91	Wethersfield	0 compounds	No	0	A-
92	Windsor	0 compounds	No	0	A-
93	Waterbury	0 compounds	No	14	C
94	New Britain	0 compounds	No	0	B-
95	Waterford	0 compounds	No	16	C-
96	Harwinton	0 compounds	No	5	D
97	Torrington	0 compounds	No	3	B+
98	Uncasville	0 compounds	No	1	A
99	New London	0 compounds	No	0	C+
100	Naugatuck	0 compounds	No	1	A
101	Barkhamsted	0 compounds	No	12	C
102	Winchester	0 compounds	No	7	A-
103	Watertown	0 compounds	No	11	D+
104	Deep River	0 compounds	No	5	C
105	Thomaston	0 compounds	No	0	A+

FAQ

Frequently asked questions about pfas in Connecticut

Does Connecticut tap water contain PFAS?

PFAS were detected in 86 of 105 Connecticut cities tested under EPA's UCMR 5 program. 79 cities exceed the 2024 EPA MCL of 4 ppt for individual PFAS compounds.

How can I remove PFAS from my drinking water in Connecticut?

Reverse osmosis (RO) systems are the most effective at removing PFAS, typically removing 90%+ of compounds. High-quality activated carbon block filters (NSF 58-certified for RO, or NSF 53 for solid carbon) also provide significant reduction. Standard pitcher filters vary widely in PFAS removal.

More contaminants