The map shows the 56 cities and towns that contain one or more public water systems that the state has officially declared exceed the standard for PFAS. The state currently regulates six long-chain chemicals:
- Perfluorooctane sulfonic acid (PFOS)
- Perfluorooctanoic acid (PFOA)
- Perfluorohexane sulfonic acid (PFHxS)
- Perfluorononanoic acid (PFNA)
- Perfluoroheptanoic acid (PFHpA)
- Perfluorodecanoic acid (PFDA)
Below is the distribution of the 75 public water systems that exceed the Maximum Contamination Level (MCL) by city and town as of Oct. 17, 2021.
While these comminities are the focus of DEP efforts to provide safe drinking water, the impact of these six PFAS chemicals is much greater as shown in the next map.
| Community | Water Systems |
| Acton | 2 |
| Attleboro | 1 |
| Ayer | 3 |
| Barnstable | 3 |
| Bedford | 1 |
| Bellingham | 1 |
| Bolton | 1 |
| Boxborough | 3 |
| Braintree | 1 |
| Brockton | 1 |
| Burlington | 1 |
| Carlisle | 2 |
| Chatham | 1 |
| Cohasset | 1 |
| Danvers | 1 |
| Dudley | 1 |
| Duxbury | 1 |
| Eastham | 1 |
| Easton | 1 |
| Foxboro | 1 |
| Grafton | 1 |
| Granby | 1 |
| Hanover | 1 |
| Harvard | 2 |
| Hudson | 1 |
| Lakeville | 1 |
| Lanesborough | 1 |
| Littleton | 1 |
| Mansfield | 1 |
| Mashpee | 2 |
| Mendon | 1 |
| Millbury | 1 |
| Millis | 1 |
| Monson | 1 |
| Natick | 1 |
| New Salem | 1 |
| Newbury | 1 |
| North Attleboro | 1 |
| North Reading | 1 |
| Norwell | 1 |
| Pepperell | 1 |
| Princeton | 2 |
| Randolph | 1 |
| Raynham | 1 |
| Rehobeth | 2 |
| Rockland | 1 |
| Sharon | 1 |
| Shirley | 1 |
| Stow | 5 |
| Sutton | 1 |
| Topsfield | 1 |
| Townsend | 1 |
| Tyngsborough | 1 |
| Wayland | 1 |
| Wellesley | 3 |
| Westport | 2 |
| Total | 75 |
(note this page has been updated with newer information here.)