Códigos ZIP con más infracciones de la EPA en Montana

Out of 54 ZIP codes with data in Montana, these are the highest-ranked areas for recorded epa violations. See also: National ZIP Codes with Most EPA Water Violations | All Montana Rankings

Statistic	Value
ZIP codes ranked	54
Highest value	133
Median value	4
State	Montana

Top 54 Worst ZIP Codes

Rank	ZIP Code	City	State	Recorded EPA Violations	Safety Score
1	59602	Helena	MT	133	50/100
2	59404	Great Falls	MT	82	—
3	59019	Columbus	MT	80	—
4	59069	Reed Point	MT	80	—
5	59601	Helena	MT	41	51/100
6	59101	Billings	MT	38	72/100
7	59901	Kalispell	MT	38	35/100
8	59106	Billings	MT	34	73/100
9	59442	Fort Benton	MT	32	—
10	59416	Brady	MT	28	—
11	59425	Conrad	MT	28	—
12	59923	Libby	MT	25	57/100
13	59912	Columbia Falls	MT	23	59/100
14	59808	Missoula	MT	21	60/100
15	59714	Belgrade	MT	10	63/100
16	59864	Ronan	MT	10	—
17	59501	Havre	MT	9	65/100
18	59860	Polson	MT	9	63/100
19	59105	Billings	MT	8	80/100
20	59323	Colstrip	MT	8	—
21	59414	Black Eagle	MT	7	—
22	59635	East Helena	MT	7	—
23	59301	Miles City	MT	6	65/100
24	59932	Somers	MT	6	—
25	59405	Great Falls	MT	5	—
26	59102	Billings	MT	4	83/100
27	59711	Anaconda	MT	4	—
28	59804	Missoula	MT	4	—
29	59044	Laurel	MT	3	82/100
30	59440	Floweree	MT	3	—
31	59468	Power	MT	3	—
32	59625	Helena	MT	3	—
33	59701	Butte	MT	3	66/100
34	59715	Bozeman	MT	3	66/100
35	59727	Divide	MT	3	66/100
36	59748	Ramsay	MT	3	—
37	59750	Butte	MT	3	—
38	59824	Charlo	MT	3	—
39	59068	Red Lodge	MT	2	—
40	59230	Glasgow	MT	2	—
41	59330	Glendive	MT	2	66/100
42	59644	Townsend	MT	2	—
43	59802	Missoula	MT	2	66/100
44	59803	Missoula	MT	2	66/100
45	59833	Florence	MT	2	—
46	59847	Lolo	MT	2	—
47	59072	Roundup	MT	1	—
48	59457	Lewistown	MT	1	66/100
49	59634	Clancy	MT	1	—
50	59716	Big Sky	MT	1	66/100
51	59718	Bozeman	MT	1	66/100
52	59730	Gallatin Gateway	MT	1	—
53	59801	Missoula	MT	1	65/100
54	59937	Whitefish	MT	1	50/100

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: 2026-08-31.

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.

Códigos ZIP con más infracciones de la EPA en Montana — 2026