State Hub
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
Top 20 of 328 by populationMwra
MA6000000 · 2,660,000 served
Boston Water and Sewer Commission (mwra)
MA3035000 · 675,647 served
Worcester Dpwp, Water Supply Division
MA2348000 · 206,518 served
Springfield Water and Sewer Commission
MA1281000 · 167,954 served
Cambridge Water Department
MA3049000 · 118,214 served
Lowell Regional Water Utility
MA3160000 · 115,000 served
Quincy Water Dept. (mwra)
MA3243000 · 106,000 served
Brockton Water Department
MA4044000 · 105,643 served
Inima Usa / Aquaria Llc
MA4076004 · 105,643 served
Lynn Water and Sewer Comm
MA3163000 · 101,253 served
City of New Bedford Dpi
MA4201000 · 101,079 served
Falmouth Water Dept
MA4096000 · 97,551 served
Fall River Water Department
MA4095000 · 94,000 served
Salem and Beverly Water Supply Board
MA3030001 · 90,330 served
Lawrence Water Works
MA3149000 · 88,877 served
Newton Water Dept. (mwra)
MA3207000 · 88,415 served
Somerville Water Dept. (mwra)
MA3274000 · 81,045 served
Framingham Water Dept. (mwra)
MA3100000 · 72,362 served
Malden Water Division (mwra)
MA3165000 · 66,263 served
Waltham Water Department
MA3308000 · 65,218 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