Connecticut Water Quality Report
Tap water quality data for 68 cities in Connecticut, updated 2026.
US average: 100 ppm
29 of 68 cities violation-free
68 cities tested
68 water systems tracked
Cleanest Tap Water in Connecticut
Cities with the fewest water quality issues
Farmington
509K served
East Granby
508K served
Windsor Locks
492K served
Meriden
477K served
West Hartford
464K served
Bethany
432K served
Ansonia
432K served
Woodbridge
432K served
Derby
420K served
Orange
420K served
Most Water Quality Issues in Connecticut
Cities with the most violations and concerns
Berlin
553K served
Newtown
361K served
Newington
477K served
Ridgefield
423K served
Stamford
553K served
Greenwich
525K served
Seymour
784K served
Darien
532K served
New Canaan
463K served
Norwalk
453K served
Water Hardness Across Connecticut
Not sure what your hardness means? Use our Water Hardness Calculator or find the best hardness test kits.
Connecticut Tap Water: What You Need to Know
Connecticut has 68 tracked water utilities serving approximately 26.5M residents. The average water hardness is 72 ppm (4.2 GPG), classified as Moderately Hard — below the national average of 100 ppm. Hardness ranges from 22.4 ppm in Cromwell to 113.5 ppm in Stratford.
In the past 3 years, 39 of 68 cities in Connecticut have recorded water quality violations, totaling 1998 violations (20 health-based). All 68 tested cities have lead levels below the EPA action level of 15 ppb.
Frequently Asked Questions About Connecticut Water
Is tap water safe to drink in Connecticut?
Most tap water in Connecticut meets EPA standards, but 39 cities have recorded violations in the past 3 years (20 health-based). We recommend checking your specific city's report on TapWater.org and considering a home water test.
How hard is the water in Connecticut?
Connecticut's average water hardness is 72 ppm (4.2 GPG), classified as Moderately Hard. This is below the national average of 100 ppm. Hardness varies significantly by city — use our Water Hardness Calculator to check your specific area.
Which city in Connecticut has the cleanest tap water?
Based on EPA violation data, lead testing, and water quality metrics, Farmington ranks as having the cleanest tap water in Connecticut. It has zero violations in the past 3 years and lead levels well below the EPA action level.
Which city in Connecticut has the most water quality issues?
Berlin currently has the most water quality concerns in Connecticut, with 109 violations in the past 3 years. Residents should check their city's detailed water quality report and consider using a certified water filter.
Where does Connecticut get its water from?
The majority of Connecticut's water systems (69%) use surface water as their primary source. Surface water comes from rivers, lakes, and reservoirs. Each city's specific source can vary — check individual city reports for details.
Largest Cities in Connecticut
The 16 biggest utilities by population served — hardness, lead status, and violations at a glance
Seymour
Utility serves 784K
Southington
Utility serves 591K
Wolcott
Utility serves 573K
Stamford
Utility serves 553K
Berlin
Utility serves 553K
Prospect
Utility serves 549K
South Windsor
Utility serves 544K
Manchester
Utility serves 544K
Darien
Utility serves 532K
Greenwich
Utility serves 525K
Cheshire
Utility serves 520K
Wallingford
Utility serves 515K
Farmington
Utility serves 509K
East Granby
Utility serves 508K
Windsor Locks
Utility serves 492K
Meriden
Utility serves 477K
More Cities in Connecticut
All 68 covered cities, A–Z
- Ansonia
- Beacon Falls
- Bethany
- Bloomfield
- Branford
- Bridgeport
- Cromwell
- Derby
- East Hartford
- East Haven
- East Windsor
- Easton
- Ellington
- Enfield
- Fairfield
- Glastonbury
- Hamden
- Hartford
- Mansfield
- Middlebury
- Milford
- Monroe
- New Canaan
- New Haven
- Newington
- Newtown
- North Branford
- North Haven
- Norwalk
- Orange
- Plainville
- Portland
- Redding
- Ridgefield
- Rocky Hill
- Shelton
- Stafford
- Stratford
- Suffield
- Tolland
- Trumbull
- Vernon
- Waterbury
- Watertown
- West Hartford
- West Haven
- Weston
- Westport
- Wethersfield
- Wilton
- Windsor
- Woodbridge