ZIP Codes with Most EPA Water Violations

Out of 23,254 ZIP codes with data across all 50 states, these are the highest-ranked areas for violations. Each ZIP links to a full safety report with water quality, lead, radon, and flood data.

Statistic	Value
ZIP codes ranked	23,254
Highest value	292
Median value	5

Top 100 Worst ZIP Codes

Rank	ZIP Code	City	State	Violations	Safety Score
1	99501	Anchorage	AK	292	70/100
2	99502	Anchorage	AK	292	70/100
3	99503	Anchorage	AK	292	70/100
4	99504	Anchorage	AK	292	65/100
5	99507	Anchorage	AK	292	65/100
6	99508	Anchorage	AK	292	65/100
7	99509	Anchorage	AK	292	66/100
8	99510	Anchorage	AK	292	70/100
9	99511	Anchorage	AK	292	66/100
10	99513	Anchorage	AK	292	66/100
11	99514	Anchorage	AK	292	66/100
12	99515	Anchorage	AK	292	70/100
13	99516	Anchorage	AK	292	70/100
14	99517	Anchorage	AK	292	70/100
15	99518	Anchorage	AK	292	70/100
16	99519	Anchorage	AK	292	70/100
17	99520	Anchorage	AK	292	66/100
18	99521	Anchorage	AK	292	66/100
19	99522	Anchorage	AK	292	66/100
20	99523	Anchorage	AK	292	66/100
21	99524	Anchorage	AK	292	66/100
22	99529	Anchorage	AK	292	66/100
23	99530	Anchorage	AK	292	66/100
24	99599	Anchorage	AK	292	66/100
25	99695	Anchorage	AK	292	66/100
26	25685	Naugatuck	WV	233	56/100
27	87101	Albuquerque	NM	220	50/100
28	87102	Albuquerque	NM	220	45/100
29	87103	Albuquerque	NM	220	33/100
30	87104	Albuquerque	NM	220	45/100
31	87105	Albuquerque	NM	220	40/100
32	87106	Albuquerque	NM	220	45/100
33	87107	Albuquerque	NM	220	40/100
34	87108	Albuquerque	NM	220	45/100
35	87109	Albuquerque	NM	220	40/100
36	87110	Albuquerque	NM	220	45/100
37	87111	Albuquerque	NM	220	45/100
38	87112	Albuquerque	NM	220	40/100
39	87113	Albuquerque	NM	220	45/100
40	87114	Albuquerque	NM	220	40/100
41	87115	Albuquerque	NM	220	33/100
42	87116	Albuquerque	NM	220	33/100
43	87119	Albuquerque	NM	220	33/100
44	87120	Albuquerque	NM	220	45/100
45	87121	Albuquerque	NM	220	40/100
46	87122	Albuquerque	NM	220	40/100
47	87123	Albuquerque	NM	220	45/100
48	87125	Albuquerque	NM	220	33/100
49	87131	Albuquerque	NM	220	33/100
50	87151	Albuquerque	NM	220	33/100
51	87153	Albuquerque	NM	220	33/100
52	87154	Albuquerque	NM	220	33/100
53	87158	Albuquerque	NM	220	33/100
54	87165	Albuquerque	NM	220	33/100
55	87176	Albuquerque	NM	220	33/100
56	87181	Albuquerque	NM	220	33/100
57	87184	Albuquerque	NM	220	33/100
58	87185	Albuquerque	NM	220	33/100
59	87187	Albuquerque	NM	220	33/100
60	87190	Albuquerque	NM	220	45/100
61	87191	Albuquerque	NM	220	33/100
62	87192	Albuquerque	NM	220	33/100
63	87193	Albuquerque	NM	220	33/100
64	87194	Albuquerque	NM	220	33/100
65	87195	Albuquerque	NM	220	33/100
66	87196	Albuquerque	NM	220	45/100
67	87197	Albuquerque	NM	220	33/100
68	87198	Albuquerque	NM	220	33/100
69	87199	Albuquerque	NM	220	33/100
70	85701	Tucson	AZ	218	58/100
71	85702	Tucson	AZ	218	50/100
72	85703	Tucson	AZ	218	50/100
73	85704	Tucson	AZ	218	58/100
74	85705	Tucson	AZ	218	53/100
75	85706	Tucson	AZ	218	58/100
76	85707	Tucson	AZ	218	50/100
77	85708	Tucson	AZ	218	50/100
78	85709	Tucson	AZ	218	50/100
79	85710	Tucson	AZ	218	53/100
80	85711	Tucson	AZ	218	58/100
81	85712	Tucson	AZ	218	53/100
82	85713	Tucson	AZ	218	58/100
83	85714	Tucson	AZ	218	58/100
84	85715	Tucson	AZ	218	53/100
85	85716	Tucson	AZ	218	53/100
86	85717	Tucson	AZ	218	50/100
87	85718	Tucson	AZ	218	53/100
88	85719	Tucson	AZ	218	53/100
89	85720	Tucson	AZ	218	50/100
90	85721	Tucson	AZ	218	50/100
91	85722	Tucson	AZ	218	50/100
92	85723	Tucson	AZ	218	50/100
93	85724	Tucson	AZ	218	50/100
94	85725	Tucson	AZ	218	50/100
95	85726	Tucson	AZ	218	50/100
96	85728	Tucson	AZ	218	50/100
97	85730	Tucson	AZ	218	58/100
98	85731	Tucson	AZ	218	50/100
99	85732	Tucson	AZ	218	50/100
100	85733	Tucson	AZ	218	50/100

Rankings by State

State	ZIP Codes Ranked
Texas	2,089
California	1,452
Florida	1,246
New York	1,162
Illinois	1,089
Pennsylvania	1,043
Ohio	762
North Carolina	710
Oklahoma	633
Missouri	630
Indiana	629
Michigan	624
Georgia	619
Wisconsin	575
Kansas	500
Colorado	484
Iowa	479
Arizona	461
Washington	436
Alabama	436
Mississippi	419
Louisiana	405
Virginia	394
West Virginia	357
Minnesota	351
Oregon	349
Tennessee	337
Massachusetts	311
New Mexico	308
New Jersey	289
Nebraska	286
District of Columbia	274
Arkansas	257
Connecticut	254
Idaho	222
South Carolina	220
Montana	212
Maine	210
Alaska	207
Maryland	196
Nevada	190
Utah	190
Kentucky	159
Vermont	157
New Hampshire	146
South Dakota	136
North Dakota	119
Wyoming	113
Delaware	66
Rhode Island	52
Hawaii	9

Methodology

Violation counts include all types recorded in the EPA SDWIS database: Maximum Contaminant Level (MCL) violations, treatment technique violations, and monitoring/reporting violations. Both resolved and unresolved violations are counted. Higher counts may reflect longer system histories or larger service areas.

Data sources: EPA Safe Drinking Water Information System (SDWIS), FEMA National Flood Insurance Program, EPA radon zone maps, EIA electricity rates, and Consumer Confidence Reports. Last updated: 2026-06-03.

Frequently Asked Questions

What counts as an EPA water violation?

EPA violations include exceeding Maximum Contaminant Levels (MCLs), failing to treat water properly (treatment technique violations), and not testing or reporting on schedule (monitoring violations). Health-based violations are the most serious.

Does a high violation count mean the water is unsafe now?

Not necessarily. Many violations are historical or monitoring-related. However, a pattern of repeated violations indicates systemic issues with water system management or infrastructure.

ZIP Codes with Most EPA Water Violations — 2026 Rank...