States / Drinking Water

Drinking Water Systems by State

48,502 community water systems nationwide; 15,916 have a health-based violation on record since 2015. Pick a state for the system-by-system list.

StateSystemsWith violation

Texas4,7491,886 (360 open)California2,8121,026 (434 open)Pennsylvania1,851821 (61 open)Oklahoma889678 (20 open)Louisiana908586 (183 open)North Carolina1,980497 (25 open)Missouri1,432466 (13 open)Illinois1,787446 (90 open)New Mexico558420 (120 open)Florida1,593419 (177 open)Wisconsin1,022411 (26 open)Colorado1,058407 (42 open)Arizona749406 (85 open)New York2,250372 (37 open)Michigan1,377364 (50 open)Oregon938361 (28 open)Kansas854332 (14 open)Mississippi1,011326 (13 open)Puerto Rico402324 (232 open)Ohio1,125314 (36 open)Arkansas659299 (34 open)Idaho765287 (23 open)West Virginia414261 (95 open)Alaska407259 (46 open)Indiana766244 (33 open)New Hampshire706239 (4 open)Nebraska583233 (1 open)Utah502232 (8 open)Washington2,311230 (4 open)Connecticut474208 (120 open)Georgia1,742200 (2 open)Kentucky373199 (8 open)Virginia1,056197 (4 open)South Dakota463191 (13 open)Montana803190 (11 open)New Jersey555183 (18 open)Maryland464165 (5 open)Massachusetts527161 (3 open)Iowa1,080132 (5 open)South Carolina562124 Minnesota968120 (8 open)Wyoming323117 (8 open)Tennessee446108 (4 open)Vermont405108 (2 open)Maine386102 (7 open)Alabama50083 (10 open)Nevada19576 (16 open)North Dakota30532 (1 open)Rhode Island8932 (6 open)Delaware20630 Hawaii11810 District of Columbia42

Source: U.S. EPA Safe Drinking Water Information System (SDWIS). Health-based = maximum contaminant level, treatment technique and maximum residual disinfectant level violations recorded since 2015. A record — especially a resolved one — is not a statement about water quality today.