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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
76–100 of 328Wellesley Water Division
MA3317000 · 29,550 served
Melrose Water Division (mwra)
MA3178000 · 29,357 served
Stoughton Water Department
MA4285000 · 29,281 served
North Attleboro Water Dept
MA4211000 · 28,863 served
West Springfield Dpw Water Division
MA1325000 · 28,835 served
Chelmsford Water District
MA3056000 · 28,750 served
Agawam Water Department
MA1005000 · 28,692 served
Bridgewater Water Department
MA4042000 · 28,633 served
Milton Water Dept. (mwra)
MA3189000 · 28,630 served
Danvers Water Dept.
MA3071000 · 28,087 served
Wannacomet Water Company
MA4197000 · 27,703 served
Belmont Water Dept. (mwra)
MA3026000 · 27,442 served
Reading Water Department (mwra)
MA3246000 · 27,358 served
Wakefield Water Dept
MA3305000 · 27,090 served
Saugus Water Dept. (mwra)
MA3262000 · 27,082 served
Burlington Water Dept
MA3048000 · 26,680 served
Dracut Water Supply District
MA3079000 · 25,808 served
Dartmouth Water Division
MA4072000 · 24,630 served
Walpole Water Dept
MA4307000 · 24,070 served
Oak Bluffs Water District
MA4221000 · 24,000 served
Mansfield Water Division
MA4167000 · 23,289 served
Stoneham Water Dept (mwra Supply)
MA3284000 · 23,244 served
Easton Water Div
MA4088000 · 23,112 served
Sandwich Water District
MA4261000 · 23,000 served
Winchester Water Dept
MA3344000 · 22,970 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
Quick Links
Data source: Utility data from EPA SDWIS. 328 active community water systems ingested. CCR contaminant data ingestion in progress.
Last updated: 2026-04-19