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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
226–250 of 328Groton Water Department
MA2115000 · 5,456 served
Topsfield Water Department
MA3298000 · 5,435 served
Lee Water Dept
MA1150000 · 5,420 served
Barnstable Fire District
MA4020000 · 5,400 served
Onset Fire Districtwater Dept.
MA4310003 · 5,392 served
Dighton Water District
MA4076000 · 5,264 served
Manchester by the Sea Dpw
MA3166000 · 5,170 served
Cotuit Fire District Water Department
MA4020003 · 4,938 served
Southampton Water Dept
MA1276000 · 4,853 served
Lynnfield Water Dist. (mwra)
MA3164001 · 4,820 served
Hadley Dpw Water Division
MA1117002 · 4,819 served
Palmer Water District No.1
MA1227000 · 4,789 served
Town of Avon
MA4018000 · 4,777 served
North Sagamore Water District
MA4036002 · 4,668 served
Sturbridge Water Department
MA2287000 · 4,567 served
Upton Dpw Water/wastewater Division
MA2303000 · 4,420 served
Tyngsborough Water District
MA3301000 · 4,416 served
Douglas Water Department
MA2077000 · 4,400 served
Great Barrington Fire Dist
MA1113000 · 4,375 served
Paxton Water Department
MA2228000 · 4,300 served
Monson Water and Sewer Dept
MA1191000 · 4,212 served
Shirley Water District
MA2270000 · 4,121 served
Barre Water Department
MA2021000 · 4,098 served
Wenham Water Dept.
MA3320000 · 3,942 served
North Brookfield Water Department
MA2212000 · 3,903 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