Question 1

Which county in Massachusetts has the best water quality?

Accepted Answer

Barnstable County has the highest water quality score in Massachusetts at 100.0/100 (Grade: A), based on EPA SDWIS data.

Question 2

Which county in Massachusetts has the most water violations?

Accepted Answer

Franklin County has among the lowest water quality scores in Massachusetts at 99.9/100. See the individual county page for detailed violation history.

Question 3

Is the tap water safe to drink in Massachusetts?

Accepted Answer

Massachusetts has an average water quality score of 100.0/100 based on EPA Safe Drinking Water Act compliance data. Individual county scores vary — check your specific county's page for detailed information.

Question 4

What contaminants are found in Massachusetts water supplies?

Accepted Answer

Drinking water quality varies by county and water system. The EPA Safe Drinking Water Information System (SDWIS) tracks violations for contaminants like lead, nitrates, bacteria, and disinfection byproducts. See individual county pages for specific contaminant and violation history.

County	Water Score	Grade	Violations	Violation Rate
Barnstable County	100.0	A	2	0.3%
Berkshire County	100.0	C	7	6.1%
Bristol County	100.0	C	39	6.2%
Dukes County	100.0	A	0	0.0%
Essex County	100.0	A	7	0.8%
Hampden County	100.0	B	12	2.8%
Hampshire County	100.0	B	3	2.2%
Middlesex County	100.0	B	30	1.9%
Nantucket County	100.0	A	0	0.0%
Norfolk County	100.0	B	33	4.3%
Plymouth County	100.0	B	21	3.8%
Suffolk County	100.0	A	0	0.0%
Worcester County	100.0	B	32	4.4%
Franklin County	99.9	C	6	12.0%

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