PFAS Testing Results

Connecticut

PFAS testing results for 63 water systems serving 2,595,014 residents.

35 systems exceed federal PFAS limits, affecting 1,703,168 residents.

Systems tested

63.5% had PFAS detections

Limits exceeded

55.6% of systems

Population affected

1.7M

served by systems over federal limits

Most common compound

11Cl-PF3OUdS

detected in 35 systems

Grade distribution

Every water system gets a letter grade based on how its worst detected PFAS compound compares to the federal Maximum Contaminant Level. Lower grades mean higher contamination.

A — 23 systems (36.5%)

B — 5 systems (7.9%)

C — 0 systems (0.0%)

D — 35 systems (55.6%)

F — 0 systems (0.0%)

How grades are calculated →

Communities exceeding federal limits

The water systems in Connecticut where at least one PFAS compound exceeds the EPA Maximum Contaminant Level, sorted worst first.

System name	City	Grade	Worst compound	Times over limit	Population
WALLINGFORD WATER DEPARTMENT	WALLINGFORD	D	PFOS	3.5x	37K
NORWICH PUBLIC UTILITIES	NORWICH	D	PFOS	3.0x	36K
NORWALK FIRST TAXING DISTRICT	NORWALK	D	PFOS	2.5x	40K
MANCHESTER WATER DEPARTMENT	MANCHESTER	D	PFOS	2.4x	51K
AQUARION WATER CO OF CT-NEWTOWN SYSTEM	SHELTON	D	PFOA	2.3x	6.1K
MERIDEN WATER DIVISION	MERIDEN	D	PFOS	2.1x	58K
COLCHESTER SEWER & WATER COMMISSION	COLCHESTER	D	PFOS	2.0x	4.0K
CTWC - SHORELINE REGION-GUILFORD SYSTEM	CLINTON	D	PFOS	2.0x	34K
AQUARION WATER CO OF CT-MAIN SYSTEM	SHELTON	D	PFOA	1.9x	352K
PUTNAM WATER POLLUTION CONTROL AUTHORITY	PUTNAM	D	PFOS	1.9x	7.3K

Resources for taking action are available in our community toolkit.

What Connecticut is doing about PFAS

Connecticut has taken an active role on PFAS since 2019, when the governor's interagency PFAS Task Force released the Connecticut PFAS Action Plan. The plan set up an AFFF take-back program that collected tens of thousands of gallons of fluorinated firefighting foam from municipal fire departments for safe disposal, one of the larger state-run collection efforts in the country.

The Connecticut Department of Energy and Environmental Protection has not adopted enforceable state MCLs for PFAS in drinking water, relying instead on the federal EPA limits finalized in April 2024. The state Department of Public Health has issued drinking water advisories near contaminated sites and required remedial actions, including at the former Loomis Chaffee School area in Windsor and the Kellogg-Deering well field in Norwalk.

State legislators passed SB 837 in 2021 banning PFAS in food packaging and firefighting foam, with product exemptions phased out through 2023. Water systems in Connecticut are subject to the federal compliance timeline requiring initial monitoring by 2027 and treatment installation by 2029.

Based on Connecticut PFAS Action Plan and Connecticut Department of Energy and Environmental Protection publications.

All 63 tested water systems in Connecticut

Sorted from lowest grade to highest. Click any system name for the full report. Filter by city or name with the search box below.

Showing 50 of 63 systems

Grade	System name	City	Worst compound	vs. EPA limit	Population
D	WALLINGFORD WATER DEPARTMENT	WALLINGFORD	PFOS	3.5× the federal limit	37K
D	NORWICH PUBLIC UTILITIES	NORWICH	PFOS	3.0× the federal limit	36K
D	NORWALK FIRST TAXING DISTRICT	NORWALK	PFOS	2.5× the federal limit	40K
D	MANCHESTER WATER DEPARTMENT	MANCHESTER	PFOS	2.4× the federal limit	51K
D	AQUARION WATER CO OF CT-NEWTOWN SYSTEM	SHELTON	PFOA	2.3× the federal limit	6.1K
D	MERIDEN WATER DIVISION	MERIDEN	PFOS	2.1× the federal limit	58K
D	COLCHESTER SEWER & WATER COMMISSION	COLCHESTER	PFOS	2.0× the federal limit	4.0K
D	CTWC - SHORELINE REGION-GUILFORD SYSTEM	CLINTON	PFOS	2.0× the federal limit	34K
D	AQUARION WATER CO OF CT-MAIN SYSTEM	SHELTON	PFOA	1.9× the federal limit	352K
D	PUTNAM WATER POLLUTION CONTROL AUTHORITY	PUTNAM	PFOS	1.9× the federal limit	7.3K
D	CTWC - CRYSTAL SYSTEM	CLINTON	PFOA	1.8× the federal limit	6.4K
D	EAST LYME WATER & SEWER COMMISSION	NIANTIC	PFOA	1.7× the federal limit	15K
D	VALLEY WATER SYSTEMS, INC.	SHELTON	PFOS	1.6× the federal limit	18K
D	Avon Water Co.	CLINTON	PFOS	1.6× the federal limit	12K
D	HAZARDVILLE WATER COMPANY	ENFIELD	PFOA	1.5× the federal limit	19K
D	AQUARION WATER CO OF CT-RIDGEFIELD SYS	SHELTON	PFOA	1.5× the federal limit	7.5K
D	REGIONAL WATER AUTHORITY	NEW HAVEN	PFOA	1.4× the federal limit	419K
D	BETHEL WATER DEPT	BETHEL	PFOA	1.4× the federal limit	9.5K
D	AQUARION WATER CO OF CT-TLWC WOODRICH	SHELTON	PFOA	1.4× the federal limit	72
D	AQUARION WATER CO OF CT-VALLEY SYSTEM	SHELTON	PFOA	1.4× the federal limit	13K
D	CTWC - UNIONVILLE SYSTEM	CLINTON	PFOS	1.4× the federal limit	15K
D	CTWC - NAUGATUCK REG-COLLINSVILLE SYS	CLINTON	PFOS	1.4× the federal limit	6.3K
D	CTWC - NORTHERN REG-WESTERN SYSTEM	CLINTON	PFOA	1.3× the federal limit	101K
D	AQUARION WATER CO OF CT-NEW MILFORD	SHELTON	PFOS	1.3× the federal limit	13K
D	SOUTHINGTON WATER DEPARTMENT	SOUTHINGTON	PFOA	1.3× the federal limit	43K
D	AQUARION WATER CO OF CT-NEW CANAAN SYS	SHELTON	PFOA	1.3× the federal limit	10K
D	AQUARION WATER CO OF CT-GREENWICH SYSTEM	SHELTON	PFOA	1.2× the federal limit	53K
D	AQUARION WATER CO OF CT-NOROTON SYSTEM	SHELTON	PFOA	1.2× the federal limit	19K
D	DANBURY WATER DEPARTMENT	DANBURY	PFOA	1.2× the federal limit	62K
D	CROMWELL FIRE DISTRICT WATER DEPARTMENT	CROMWELL	PFOS	1.1× the federal limit	14K
D	UNIVERSITY OF CONNECTICUT - MAIN CAMPUS	STORRS	PFOS	1.1× the federal limit	27K
D	AQUARION WATER CO OF CT-SIMSBURY SYSTEM	SHELTON	PFOS	1.1× the federal limit	15K
D	AQUARION WATER CO OF CT-STAMFORD	SHELTON	PFOA	1.1× the federal limit	119K
D	BRISTOL WATER DEPARTMENT	BRISTOL	PFOA	1.0× the federal limit	52K
D	HERITAGE WATER COMPANY	CLINTON	PFOA	1.0× the federal limit	7.3K
B	BERLIN WATER CONTROL COMMISSION	BERLIN	PFHxS	Below federal limit	5.1K
B	JEWETT CITY WATER COMPANY	ENFIELD	PFBA	Below detection	6.8K
B	PORTLAND WATER DEPARTMENT	PORTLAND	PFPeA	Below detection	5.0K
B	AQUARION WATER CO OF CT-MYSTIC	SHELTON	PFBS	Below detection	11K
B	WINDHAM WATER WORKS	MANSFIELD CENTER	PFHxA	Below detection	21K
A	STERLING ENGINEERING CORP.	BARKHAMSTED	-	Below detection	110
A	KENSINGTON FIRE DISTRICT	KENSINGTON	-	Below detection	7.6K
A	CTWC - SHORELINE REGION-CHESTER SYSTEM	CLINTON	-	Below detection	5.0K
A	CTWC - COVENTRY HILLS DIV	CLINTON	-	Below detection	700
A	GREENWICH AMERICAN CENTER	GREENWICH	-	Below detection	800
A	GROTON UTILITIES	GROTON	-	Below detection	30K
A	METROPOLITAN DISTRICT COMMISSION	HARTFORD	-	Below detection	391K
A	AQUARION WATER CO OF CT-LITCHFIELD SYS	SHELTON	-	Below detection	3.1K
A	MIDDLEBURY HAMLET	PROSPECT	-	Below detection	75
A	MIDDLETOWN WATER DEPARTMENT	MIDDLETOWN	-	Below detection	41K

Check your water system

Enter your zip code to see the PFAS results for the water system that serves your home.

Where this data comes from

EPA Unregulated Contaminant Monitoring Rule, 5th cycle (UCMR 5)
Testing period: 2023 to 2026
Federal limits: EPA Maximum Contaminant Levels finalized April 2024
Read the full methodology