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States with the Most Drinking Water Violations

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All states ranked by total Safe Drinking Water Act violations, where water systems most often fail federal standards.

What This Ranking Tells Us

Water violations occur when public water systems fail to meet EPA standards under the Safe Drinking Water Act. These include maximum contaminant level (MCL) violations for harmful substances, treatment technique violations, and monitoring/reporting failures. States with the most violations may have aging infrastructure, challenged rural systems, or naturally occurring contaminants like arsenic or radium. High violation counts do not always mean unsafe water, many are procedural rather than health-based.

This page ranks all 50 U.S. states and territories on a single indicator - violations - drawn directly from the EPA Safe Drinking Water Information System (SDWIS). The ranking draws on 51 state records in the current dataset, ordered descending (highest count at the top) by the underlying federal count.

The top of the table is led by Texas with a reported value of 33,822, followed by Oklahoma (28,341) and California (17,550). The bottom of the ranking ends with Northern Mariana Islands at 165, illustrating the spread across the federal record.

A state's position depends on underlying geography, industrial history, population, and the density of reporting entities, not on a simple "cleaner" or "dirtier" label. Use the links in the table to open each state's full environmental profile and view county-level breakdowns, individual facility records, and violation history. Data source: EPA Safe Drinking Water Information System (SDWIS). All figures are as-filed and not weighted for toxicity or exposure.

States with the Most Drinking Water Violations: top 15

Ranked by violations - full table below

violations

What this shows Rankings reflect reported federal totals, shaped by each state's geography, industrial history and population, not a direct measure of health risk or water safety.

Source EPA Safe Drinking Water Information System (SDWIS) As of most recent EPA release
#1 Texas 33,822 violations #2 Oklahoma 28,341 violations #3 California 17,550 violations
# State Violations
1 Texas TX 33,822
2 Oklahoma OK 28,341
3 California CA 17,550
4 Louisiana LA 13,618
5 New Mexico NM 7,529
6 Missouri MO 6,246
7 Arkansas AR 5,811
8 Colorado CO 5,332
9 New York NY 5,270
10 Pennsylvania PA 5,198
11 Arizona AZ 4,821
12 Alaska AK 4,613
13 Kansas KS 3,784
14 Puerto Rico PR 2,826
15 Illinois IL 2,825
16 North Carolina NC 2,788
17 Washington WA 2,705
18 Florida FL 2,676
19 Georgia GA 2,663
20 Oregon OR 2,578
21 West Virginia WV 2,371
22 Wisconsin WI 2,233
23 Idaho ID 2,204
24 Nebraska NE 2,160
25 Virginia VA 1,855
26 Mississippi MS 1,850
27 Kentucky KY 1,788
28 Indiana IN 1,467
29 Montana MT 1,430
30 New Hampshire NH 1,402
31 Ohio OH 1,386
32 Utah UT 1,200
33 South Dakota SD 1,192
34 New Jersey NJ 1,109
35 Massachusetts MA 1,106
36 Tennessee TN 1,091
37 Vermont VT 1,090
38 Michigan MI 1,000
39 Nevada NV 970
40 Minnesota MN 845
41 Maine ME 799
42 Connecticut CT 749
43 Iowa IA 729
44 Wyoming WY 713
45 South Carolina SC 647
46 Maryland MD 506
47 Alabama AL 485
48 American Samoa AS 278
49 Rhode Island RI 186
50 North Dakota ND 169
51 Northern Mariana Islands MP 165

Source: EPA Safe Drinking Water Information System (SDWIS).

Frequently Asked Questions

What is a drinking water violation?

Violations occur when a public water system fails to meet EPA requirements under the Safe Drinking Water Act. Health-based violations mean contaminants exceeded maximum allowed levels. Monitoring violations mean the system failed to test water as required. Treatment technique violations mean the system failed to properly treat water. All violations are reported to state primacy agencies and the EPA.

Are states with more violations more dangerous?

Not necessarily. States with many water systems naturally have more opportunities for violations. A state with 5,000 systems and 500 violations may have a lower violation rate than one with 100 systems and 50 violations. The violation type also matters, health-based violations are more concerning than paperwork lapses.

What happens when a water system has a violation?

Systems must notify consumers, often through public notices or boil-water advisories. The state enforces corrective actions, which can include fines, mandatory treatment upgrades, or operational changes. Persistent violators may face federal enforcement actions from the EPA.

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What to do with this ranking

Use the leaders here as a starting point, then check your own state's full record.

  • Texas tops this list at 33,822 violations - see its full environmental profile, not just this one metric. View Texas
  • This single indicator doesn't capture the full picture. Compare against most tri facilities for a different angle. Most TRI Facilities
  • Look up any state directly to see its complete facility, water, and Superfund record in one place. Browse all states

Rankings reflect reported federal data for a single indicator; a high or low rank does not by itself measure overall environmental quality or health risk.

Read our methodology - how this data is sourced, computed, and verified.

According to the U.S. Environmental Protection Agency, this ranking is drawn from PlainEnviro's database of more than 25,000 EPA-tracked facilities and thousands of Safe Drinking Water Information System and Superfund National Priorities List records compiled since federal reporting began under the Emergency Planning and Community Right-to-Know Act in October 1986; see our methodology for the full data-source citations and refresh cadence.

Related

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Data sourced from U.S. EPA environmental datasets. See our methodology for details. Retrieved and formatted by PlainEnviro Editorial

Every figure on PlainEnviro is rendered directly from EPA environmental compliance data, no number is typed in by an editor. Rankings are computed directly from EPA data. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.