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Massachusetts Water Quality
328
Utilities in database
10.0M
Residents served
18%
On private wells
3
Key contaminants tracked
Drinking Water in Massachusetts
Massachusetts has 328 community water systems serving approximately 10.0 million residents. Primary water sources include surface water. The most commonly reported contaminants include lead, disinfection byproducts, nitrates. 18% of Massachusetts residents rely on private wells. DEP holds primary enforcement authority under the Safe Drinking Water Act.
Utilities in Massachusetts
151–175 of 328Medway Water Department
MA2177000 · 13,115 served
Ipswich Dpu Water Dept
MA3144000 · 13,090 served
North Adams Water Dept
MA1209000 · 13,000 served
Medfield Water Dept.
MA2175000 · 12,894 served
Hopkinton Water Department
MA2139000 · 12,586 served
Auburn Water District
MA2017000 · 12,255 served
Wrentham Water Division
MA4350000 · 12,190 served
Weston Water Dept.
MA3333000 · 11,941 served
Hanscom Afb
MA3023002 · 11,789 served
Uxbridge Dpw, Water Division
MA2304000 · 11,525 served
Norwell Water Department
MA4219000 · 11,495 served
Holbrook Public Works Dept
MA4133000 · 11,405 served
Ash/win Joint Water Authority
MA2011004 · 11,394 served
Aquarion Water Company, Millbury
MA2186000 · 11,326 served
Grafton Water District
MA2110000 · 10,925 served
Raynham Center Water District
MA4245000 · 10,824 served
Athol Dpw Water Division
MA1015000 · 10,587 served
Southborough Dpw Water Division (mwra)
MA2277000 · 10,514 served
Maynard Dpw, Water Division
MA2174000 · 10,401 served
Ware Water Dept
MA1309000 · 10,066 served
Rockport Water Dept
MA3252000 · 10,000 served
Blackstone Water Department
MA2032000 · 9,868 served
Lenox Dpw Water Division
MA1152000 · 9,800 served
Kenwood Water District
MA3079001 · 9,620 served
Littleton Water Department
MA2158000 · 9,611 served
Key Contaminant Concerns in Massachusetts
Lead
Lead is a naturally occurring heavy metal that was widely used in plumbing infrastructure until it was banned for new installations in 1986. An estimated 9.2 million lead service lines still connect homes to public water mains across the United States, along with millions of homes with lead solder in their internal plumbing.
Nitrates
Nitrate (NO₃⁻) is a nitrogen-containing compound that forms naturally through the decomposition of organic matter. At elevated concentrations — almost always from human activity — nitrate interferes with the blood's ability to carry oxygen. The United States produces over 23 million tons of nitrogen fertilizer annually, making agricultural runoff the dominant source of nitrate contamination.
DBPs
When utilities add chlorine to water to kill pathogens, it reacts with dissolved organic matter — leaves, algae, soil — to produce disinfection byproducts (DBPs). Over 600 DBPs have been identified. The EPA regulates two groups: total trihalomethanes (TTHMs, including chloroform) and haloacetic acids (HAA5). DBP levels tend to be highest in surface water systems and in warm months when organic matter is elevated.
Massachusetts Water FAQs
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Data source: Utility data from EPA SDWIS. 328 active community water systems ingested. CCR contaminant data ingestion in progress.
Last updated: 2026-04-19