Connecticut Water Quality Ratings

TapWaterSafety has rated 10 public water systems in Connecticut, serving a combined 1,736,668 residents. The statewide average grade is F.

Data sources: EPA SDWIS EPA ECHO EWG Tap Water Database Utility CCRs ⓘ How did we get these ratings?
State average grade
F
59/100
Total utilities rated 10
Population served 1,736,668
🇪🇺 Would fail EU standards 1 of 10

Top water quality concerns in Connecticut

  • Haloacetic acids (HAA9) significantly above health guideline
  • Total trihalomethanes (TTHMs) significantly above health guideline
  • Haloacetic acids (HAA5) significantly above health guideline
  • PFAS contamination
  • Arsenic significantly above health guideline

Cities in Connecticut

Browse tap water quality reports by city. Click any city to see its grade, what's in the water, and recommended filters.

ANSONIA
F 418,900
BEACON FALLS
F 351,756
BERLIN
D 522,862
BETHANY
F 418,900
BETHEL
D 62,055
BLOOMFIELD
D 390,887
BRANFORD
F 418,900
BRIDGEPORT
F 351,756
BROOKFIELD
D 62,055
CHESHIRE
F 477,341
CROMWELL
D 390,887
DANBURY
D 62,055
DARIEN
F 470,970
DERBY
F 418,900
EAST GRANBY
F 492,200
EAST HARTFORD
D 390,887
EAST HAVEN
F 418,900
EAST WINDSOR
F 101,313
EASTON
F 351,756
ELLINGTON
F 101,313
ENFIELD
F 101,313
FAIRFIELD
F 351,756
FARMINGTON
D 464,421
GLASTONBURY
D 390,887
GREENWICH
F 524,267
HAMDEN
F 418,900
HARTFORD
D 390,887
MANCHESTER
F 492,200
MANSFIELD
F 101,313
MERIDEN
F 477,341
MIDDLEBURY
F 107,271
MILFORD
F 418,900
MONROE
F 351,756
NEW BRITAIN
D 73,534
NEW CANAAN
F 351,756
NEW HAVEN
F 418,900
NEWINGTON
D 464,421
NEWTOWN
F 351,756
NORTH BRANFORD
F 418,900
NORTH HAVEN
F 418,900
NORWALK
F 351,756
ORANGE
F 418,900
PLAINVILLE
D 73,534
PORTLAND
D 390,887
PROSPECT
F 526,171
REDDING
F 351,756
RIDGEFIELD
F 413,811
ROCKY HILL
D 390,887
SEYMOUR
F 770,656
SHELTON
F 351,756
SOUTH WINDSOR
F 492,200
SOUTHINGTON
F 477,341
STAFFORD
F 101,313
STAMFORD
F 524,267
STRATFORD
F 351,756
SUFFIELD
F 101,313
TOLLAND
F 101,313
TRUMBULL
F 351,756
VERNON
F 101,313
WALLINGFORD
F 477,341
WATERBURY
F 107,271
WATERTOWN
F 107,271
WEST HARTFORD
D 464,421
WEST HAVEN
F 418,900
WESTON
F 351,756
WESTPORT
F 351,756
WETHERSFIELD
D 390,887
WILTON
F 351,756
WINDSOR
D 390,887
WINDSOR LOCKS
F 492,200
WOLCOTT
F 526,171
WOODBRIDGE
F 418,900

Grade distribution

A
0 (0%)
B
0 (0%)
C
3 (30%)
D
4 (40%)
F
3 (30%)

All rated utilities in Connecticut

Sorted by score, highest first. Click any utility to see the full grade card.

Rank Utility City Population Score Grade
#1 DANBURY WATER DEPARTMENT BETHEL 62,055 67 C
#2 NEW BRITAIN WATER DEPARTMENT BERLIN 73,534 67 C
#3 METROPOLITAN DISTRICT COMMISSION BERLIN 390,887 65 C
#4 AQUARION-GREENWICH GREENWICH 53,297 63 D
#5 AQUARION-STAMFORD DARIEN 119,214 63 D
#6 REGIONAL WATER AUTHORITY ANSONIA 418,900 55 D
#7 WATERBURY WATER DEPARTMENT MIDDLEBURY 107,271 55 D
#8 CTWC - NORTHERN REG-WESTERN SYSTEM EAST GRANBY 101,313 53 F
#9 MERIDEN WATER DIVISION BERLIN 58,441 53 F
#10 AQUARION-EASTERN FAIRFIELD COUNTY BEACON FALLS 351,756 51 F