Lower record-based concern — Population-weighted indicator 90/100
State Overview
Water quality across Massachusetts receives an record-only indicator of A (Lower record-based concern) with an average score of 90 out of 100, based on EPA compliance data from 545 ZIP codes statewide. A majority of ZIP codes (63%) earn an A grade, within this record-based model; this does not establish tap-water safety. The lowest-scoring area is ZIP code 01519 (Grafton) with a score of 46/100. Scores are calculated from EPA Safe Drinking Water Information System (SDWIS) violation records, lead and copper testing results, PFAS monitoring data from UCMR5, and enforcement actions over the past 5 years. Boston Water and Sewer Commission (MWRA): ZIP 02108 Utility reports corroborate system identity; the EPA crosswalk provides ZIP associations. These reports do not certify water at an individual tap.Reports with documented service-area checks
Choose a ZIP code below to review the public water systems associated with that area, five-year SDWIS violation history, available lead and copper results, UCMR5 PFAS occurrence records, enforcement actions and the limits of the geographic mapping. These reports describe public records, not the condition of water at an individual tap.
Lowest Scoring ZIP Codes