States with the Most Drinking Water Violations

These states have the most EPA Safe Drinking Water Act violations on record. Higher numbers can reflect larger populations, more water systems, or systemic infrastructure challenges rather than worse water quality alone.

# ▴▾ State ▴▾ Total Violations ▴▾ Health Violations ▴▾ Water Systems ▴▾ Population ▴▾
1 Texas 263,180 39,140 4,713 32,406,355
2 Pennsylvania 199,265 6,042 1,855 11,468,960
3 Oklahoma 128,472 29,472 889 3,653,817
4 New York 93,834 5,682 2,245 18,268,008
5 West Virginia 81,622 2,703 412 1,546,947
6 Alaska 73,527 5,020 405 699,435
7 Utah 71,655 0 559 3,702,006
8 Ohio 61,604 0 1,094 10,443,946
9 Arizona 60,414 4,414 751 7,093,233
10 Washington 54,459 2,509 2,311 9,192,864
11 North Carolina 54,399 3,287 1,979 9,538,792
12 Colorado 42,596 5,256 1,048 7,175,420
13 California 39,276 18,881 2,819 40,093,669
14 New Mexico 37,115 7,761 555 1,923,604
15 Florida 36,335 3,132 1,593 21,963,405
16 Georgia 32,159 3,145 1,739 10,561,974
17 Louisiana 32,039 16,153 917 5,225,688
18 Illinois 30,544 3,286 1,782 12,123,082
19 Connecticut 28,800 729 475 2,726,278
20 Idaho 26,078 2,547 764 1,565,041
21 Missouri 25,377 3,923 1,431 5,651,462
22 Mississippi 25,296 2,328 1,012 3,200,594
23 Tennessee 20,607 0 453 7,862,060
24 Montana 20,202 1,220 792 789,179
25 South Dakota 19,565 0 512 927,151
26 Kansas 19,480 3,703 856 2,869,691
27 New Jersey 19,332 1,125 555 8,881,952
28 Wisconsin 18,533 2,518 1,021 4,230,296
29 Indiana 18,261 1,720 771 5,231,741
30 Arkansas 17,031 6,234 665 3,019,237
31 Michigan 15,820 1,211 1,381 7,509,650
32 Virginia 15,298 2,604 1,062 7,437,928
33 Alabama 13,972 471 501 6,168,671
34 Wyoming 13,783 742 323 536,350
35 South Carolina 13,045 0 557 4,631,800
36 Vermont 12,362 1,306 405 466,945
37 Massachusetts 10,561 937 525 10,050,324
38 Kentucky 9,427 1,801 374 4,556,638
39 Iowa 9,389 934 1,076 3,000,306
40 North Dakota 8,431 0 318 743,065
41 Nevada 8,167 1,162 192 3,119,117
42 New Hampshire 6,968 1,699 710 920,024
43 Maine 6,830 913 387 691,040
44 Maryland 5,321 594 461 5,523,173
45 Nebraska 5,134 2,253 585 1,706,785
46 Minnesota 3,784 733 965 4,670,079
47 Delaware 1,242 314 207 1,018,198
48 Hawaii 182 44 119 1,507,224
49 District of Columbia 115 23 4 667,325
50 Oregon 0 0 0 0
51 Rhode Island 0 0 0 0

Key Takeaways

  • States with larger populations and more water systems tend to have more total violations.
  • Total violations include both health-based violations (contaminant levels exceeded) and monitoring/reporting violations.
  • A high violation count does not necessarily mean worse water quality — it may reflect more thorough testing and enforcement.

Methodology

Data is sourced from the EPA Safe Drinking Water Information System (SDWIS) via the Envirofacts API. Rankings include community water systems serving 100 or more people. Violation counts reflect historical records in the SDWIS database and include both resolved and unresolved violations. Health-based violations include Maximum Contaminant Level (MCL) violations and Treatment Technique violations. Per-capita calculations use the total population served by tracked water systems in each state.

Verify data at epa.gov