ZIP Codes with Most EPA Violations in Massachusetts ...

Out of 311 ZIP codes with data in Massachusetts, these are the highest-ranked areas for violations. See also: National ZIP Codes with Most EPA Water Violations | All Massachusetts Rankings

Statistic	Value
ZIP codes ranked	311
Highest value	37
Median value	2
State	Massachusetts

Top 100 Worst ZIP Codes

Rank	ZIP Code	City	State	Violations	Safety Score
1	01921	Boxford	MA	37	49/100
2	01719	Boxborough	MA	23	65/100
3	02703	Attleboro	MA	23	59/100
4	02093	Wrentham	MA	21	58/100
5	01005	Barre	MA	18	56/100
6	01519	Grafton	MA	10	53/100
7	02330	Carver	MA	10	78/100
8	01230	Great Barrington	MA	9	74/100
9	01540	Oxford	MA	9	68/100
10	01749	Hudson	MA	9	56/100
11	02324	Bridgewater	MA	9	70/100
12	02325	Bridgewater	MA	9	73/100
13	01505	Boylston	MA	8	59/100
14	01524	Leicester	MA	8	54/100
15	01611	Cherry Valley	MA	8	55/100
16	02347	Lakeville	MA	8	67/100
17	02348	Lakeville	MA	8	72/100
18	01469	Townsend	MA	7	59/100
19	01501	Auburn	MA	7	64/100
20	01746	Holliston	MA	7	59/100
21	02667	Wellfleet	MA	7	69/100
22	01527	Millbury	MA	6	53/100
23	01560	South Grafton	MA	6	64/100
24	02019	Bellingham	MA	6	74/100
25	02056	Norfolk	MA	6	74/100
26	02338	Halifax	MA	6	72/100
27	02554	Nantucket	MA	6	59/100
28	02584	Nantucket	MA	6	74/100
29	02714	Dartmouth	MA	6	62/100
30	02725	Somerset	MA	6	42/100
31	02726	Somerset	MA	6	37/100
32	02766	Norton	MA	6	53/100
33	01106	Longmeadow	MA	5	78/100
34	01116	Longmeadow	MA	5	77/100
35	01432	Ayer	MA	5	68/100
36	01515	East Brookfield	MA	5	68/100
37	01543	Rutland	MA	5	61/100
38	01568	Upton	MA	5	50/100
39	01580	Westborough	MA	5	62/100
40	01581	Westborough	MA	5	61/100
41	01582	Westborough	MA	5	62/100
42	01810	Andover	MA	5	47/100
43	01812	Andover	MA	5	56/100
44	01876	Tewksbury	MA	5	58/100
45	01899	Andover	MA	5	56/100
46	02030	Dover	MA	5	68/100
47	02050	Marshfield	MA	5	58/100
48	02066	Scituate	MA	5	51/100
49	02343	Holbrook	MA	5	68/100
50	05501	Andover	MA	5	56/100
51	05544	Andover	MA	5	56/100
52	01085	Westfield	MA	4	72/100
53	01086	Westfield	MA	4	82/100
54	02360	Plymouth	MA	4	62/100
55	02361	Plymouth	MA	4	72/100
56	02362	Plymouth	MA	4	77/100
57	02364	Kingston	MA	4	77/100
58	02368	Randolph	MA	4	70/100
59	02571	Wareham	MA	4	63/100
60	02715	Dighton	MA	4	65/100
61	02743	Acushnet	MA	4	78/100
62	02764	North Dighton	MA	4	70/100
63	01011	Chester	MA	3	74/100
64	01235	Hinsdale	MA	3	58/100
65	01330	Ashfield	MA	3	80/100
66	01441	Westminster	MA	3	62/100
67	01451	Harvard	MA	3	63/100
68	01473	Westminster	MA	3	67/100
69	01503	Berlin	MA	3	63/100
70	01748	Hopkinton	MA	3	61/100
71	01757	Milford	MA	3	57/100
72	01821	Billerica	MA	3	43/100
73	01822	Billerica	MA	3	51/100
74	01940	Lynnfield	MA	3	59/100
75	01949	Middleton	MA	3	59/100
76	02025	Cohasset	MA	3	69/100
77	02043	Hingham	MA	3	70/100
78	02044	Hingham	MA	3	80/100
79	02108	Boston	MA	3	84/100
80	02109	Boston	MA	3	79/100
81	02110	Boston	MA	3	84/100
82	02111	Boston	MA	3	89/100
83	02112	Boston	MA	3	92/100
84	02113	Boston	MA	3	89/100
85	02114	Boston	MA	3	84/100
86	02115	Boston	MA	3	84/100
87	02116	Boston	MA	3	84/100
88	02117	Boston	MA	3	92/100
89	02118	Boston	MA	3	84/100
90	02123	Boston	MA	3	92/100
91	02127	Boston	MA	3	84/100
92	02128	Boston	MA	3	84/100
93	02133	Boston	MA	3	92/100
94	02163	Boston	MA	3	89/100
95	02196	Boston	MA	3	92/100
96	02199	Boston	MA	3	89/100
97	02201	Boston	MA	3	92/100
98	02203	Boston	MA	3	92/100
99	02204	Boston	MA	3	92/100
100	02205	Boston	MA	3	92/100

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: 2026-06-04.

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.