Massachusetts water quality
Massachusetts has 1,849 active public water systems (3,797 on file total), 563 of them graded by TapGraded.
Grade distribution
Biggest water systems
MWRA
CHELSEA, MA · 2,580,000 served
BOSTON WATER AND SEWER COMMISSION (MWRA)
BOSTON, MA · 675,647 served
WORCESTER DPWP, WATER SUPPLY DIVISION
WORCESTER, MA · 206,518 served
SPRINGFIELD WATER AND SEWER COMMISSION
SPRINGFIELD, MA · 169,170 served
LOWELL REGIONAL WATER UTILITY
LOWELL, MA · 120,418 served
CAMBRIDGE WATER DEPARTMENT
CAMBRIDGE, MA · 118,214 served
QUINCY WATER DEPT. (MWRA)
QUINCY, MA · 106,000 served
BROCKTON WATER DEPARTMENT
BROCKTON, MA · 105,788 served
INIMA USA / AQUARIA LLC
NORTH DIGHTON, MA · 105,643 served
LYNN WATER AND SEWER COMM
LYNN, MA · 101,253 served
Lowest-graded systems
Active, graded systems serving at least 10,000 people, ordered by lowest Tap Grade first.
DARTMOUTH WATER DIVISION
DARTMOUTH, MA · 24,696 served
BILLERICA WATER WORKS
BILLERICA, MA · 42,119 served
IPSWICH DPU WATER DEPT
IPSWICH, MA · 13,138 served
TEWKSBURY WATER DEPARTMENT
TEWKSBURY, MA · 31,342 served
WESTBOROUGH WATER DEPARTMENT
WESTBOROUGH, MA · 21,567 served
SCITUATE WATER DIVISION
SCITUATE, MA · 19,297 served
BELLINGHAM DPW WATER SEWER DIVISION
BELLINGHAM, MA · 16,556 served
GRAFTON WATER DISTRICT
GRAFTON, MA · 10,925 served
SUDBURY WATER DISTRICT
SUDBURY, MA · 18,416 served
CONCORD WATER DEPT
CONCORD, MA · 18,788 served
Cities in Massachusetts
Source: EPA SDWIS/ECHO · Data as of 2026Q2