| Abington/rockland Joint Water Works | Rockland, MA | 33,887 |
| Acton Water Supply District | Acton, MA | 20,890 |
| Agawam Water Department | Agawam, MA | 28,849 |
| Amesbury DPW Water Div. | Amesbury, MA | 16,283 |
| Amherst DPW Water Division | Amherst, MA | 37,819 |
| Andover Water Department | Andover, MA | 33,201 |
| Arlington Water Department (MWRA) | Arlington, MA | 42,844 |
| Ashland Water and Sewer Department | Ashland, MA | 16,593 |
| Athol DPW Water Division | Athol, MA | 10,172 |
| Attleboro Water Department | Attleboro, MA | 43,593 |
| Auburn Water District | Auburn, MA | 11,763 |
| Bedford Water Department (MWRA) | Bedford, MA | 13,691 |
| Bellingham Dpw Water Sewer Div. | Bellingham, MA | 15,390 |
| Belmont Water Department (MWRA) | Belmont, MA | 24,254 |
| Beverly Water Department | Beverly, MA | 43,316 |
| Billerica Water Works | Billerica, MA | 40,243 |
| Boston Water and Sewer Commission (MWRA) | Boston, MA | 617,594 |
| Bourne Water District | Pocasset, MA | 22,500 |
| Braintree Water and Sewer Department | Braintree, MA | 37,544 |
| Brewster Water Department | Brewster, MA | 35,000 |
| Bridgewater Water Department | Bridgewater, MA | 26,563 |
| Brockton Water Commission | Brockton, MA | 93,810 |
| Brookline Water And Sewer Div. (MWRA) | Brookline, MA | 58,732 |
| Burlington Water Department | Burlington, MA | 25,392 |
| Cambridge Water Department (MWRA) | Cambridge, MA | 105,162 |
| Canton Water Department (MWRA) | Canton, MA | 21,458 |
| Centerville Osterville Marstons Mills WD | Osterville, MA | 50,000 |
| Chatham Water Department | Chatham, MA | 30,000 |
| Chelmsford Water District | Chelmsford, MA | 28,079 |
| Chelsea Water Department (MWRA) | Chelsea, MA | 35,177 |
| Chicopee Water Department (MWRA) | Chicopee, MA | 55,144 |
| Clinton Water Department (MWRA) | Clinton, MA | 13,606 |
| Concord Water Department | Concord, MA | 16,402 |
| Danvers Water Department | Middleton, MA | 26,493 |
| Dartmouth Water Division | Dartmouth, MA | 24,272 |
| Dedham Westwood Water District | Dedham, MA | 42,581 |
| Dennis Water District | South Dennis, MA | 65,000 |
| Dracut Water Supply District | Dracut, MA | 25,741 |
| Duxbury Water Department | Duxbury, MA | 16,445 |
| East Bridgewater Water Department | East Bridgewater, MA | 13,794 |
| East Longmeadow DPW Water Department | East Longmeadow, MA | 16,162 |
| Easthampton Water Department | Easthampton, MA | 16,053 |
| Easton Water Div | Easton, MA | 23,112 |
| Everett Water Department (MWRA) | Everett, MA | 42,101 |
| Fairhaven Water Department | Fairhaven, MA | 15,792 |
| Fall River Water Department | Fall River, MA | 88,857 |
| Falmouth Water Department | Falmouth, MA | 77,500 |
| Fitchburg Dpw, Div. of Water Supply | Fitchburg, MA | 40,545 |
| Foxboro Water Department | Foxborough, MA | 16,924 |
| Framingham Water Department (MWRA) | Framingham, MA | 68,318 |
| Franklin Water Department | Franklin, MA | 32,445 |
| Gardner Water Department | Gardner, MA | 19,314 |
| Gloucester DPW Water Department | Gloucester, MA | 37,715 |
| Grafton Water District | Grafton, MA | 10,703 |
| Greenfield Water Department | Greenfield, MA | 17,645 |
| Hanover Water Department | Hanover, MA | 14,899 |
| Hanscom AFB | Hanscom Afb, MA | 11,799 |
| Harwich Water Department | East Harwich, MA | 38,643 |
| Haverhill Water Department | Haverhill, MA | 57,311 |
| Holbrook Public Works Department | Holbrook, MA | 10,791 |
| Holden Water Division, DPW | Holden, MA | 17,106 |
| Holliston Water Department | Holliston, MA | 14,946 |
| Holyoke Water Works | Holyoke, MA | 40,124 |
| Hudson Water Supply | Hudson, MA | 18,406 |
| Hyannis Water System | Hyannis, MA | 35,000 |
| Ipswich DPU Water Department | Ipswich, MA | 13,127 |
| Kingston Water Department | Kingston, MA | 13,720 |
| Lawrence Water Works | Lawrence, MA | 76,377 |
| Leominster Water Division (MWRA) | Leominster, MA | 40,490 |
| Lexington Water Department (MWRA) | Lexington, MA | 32,271 |
| Longmeadow Water Department | Longmeadow, MA | 15,701 |
| Lowell Regional Water Utility | Lowell, MA | 106,519 |
| Lynn Water and Sewer Commission (MWRA) | Lynn, MA | 90,329 |
| Malden Water Division (MWRA) | Malden, MA | 59,450 |
| Mansfield Water Division | Mansfield, MA | 23,380 |
| Marblehead Water Department (MWRA) | Marblehead, MA | 19,432 |
| Marlborough DPW Water Div. (MWRA) | Marlborough, MA | 38,499 |
| Marshfield Water Department | Marshfield, MA | 34,000 |
| Mashpee Water District | Mashpee, MA | 34,681 |
| Maynard DPW, Water Division | Maynard, MA | 10,665 |
| Medfield Water Department | Medfield, MA | 12,595 |
| Medford Water Department (MWRA) | Medford, MA | 57,000 |
| Melrose Water Department (MWRA) | Melrose, MA | 28,367 |
| Methuen Water Department | Methuen, MA | 50,259 |
| Middleborough Water Supply | Middleborough, MA | 16,470 |
| Milford Water Company | Milford, MA | 27,999 |
| Milton Water Department (MWRA) | Milton, MA | 27,003 |
| Natick Water Department | Natick, MA | 36,137 |
| Needham Water Department (MWRA) | Needham, MA | 32,485 |
| New Bedford Department of Public Infrastructure | New Bedford, MA | 95,072 |
| Newburyport Water Department | Newburyport, MA | 20,335 |
| Newton Water Department (MWRA) | Newton, MA | 89,045 |
| North Adams Water Department | North Adams, MA | 13,000 |
| North Andover Water Department | North Andover, MA | 27,500 |
| North Attleboro Water Department | North Attleborough, MA | 28,712 |
| North Reading Water Department | North Reading, MA | 15,500 |
| Northampton Water Department | Northampton, MA | 28,548 |
| Northborough Water Department (mwra) | Northborough, MA | 11,490 |
| Norton Water Department | Norton, MA | 19,031 |
| Norwell Water Department | Norwell, MA | 11,258 |
| Norwood Water Department (MWRA) | Norwood, MA | 26,789 |
| Oak Bluffs Water District | Oak Bluffs, MA | 22,452 |
| Orleans Water Department | Orleans, MA | 17,670 |
| Peabody Water Department (MWRA) | Peabody, MA | 52,474 |
| Pembroke Water Division Dpw | Pembroke, MA | 19,189 |
| Pittsfield DPU Water Department | Pittsfield, MA | 44,737 |
| Plymouth Water Department | Plymouth, MA | 41,499 |
| Provincetown Water Department | Provincetown, MA | 22,250 |
| Quincy Water Department (MWRA) | Quincy, MA | 96,329 |
| Randolph Water Department | Randolph, MA | 33,375 |
| Reading Water Department | Reading, MA | 27,045 |
| Revere Water Department (MWRA) | Revere, MA | 51,755 |
| Rockport Water Department | Rockport, MA | 10,000 |
| Salem Water Department | Salem, MA | 42,869 |
| Salisbury Water Department | Salisbury, MA | 20,000 |
| Sandwich Water District | Sandwich, MA | 23,000 |
| Saugus Water Department (MWRA) | Saugus, MA | 24,703 |
| Scituate Water Division | Scituate, MA | 19,688 |
| Seekonk Water District | Seekonk, MA | 13,627 |
| Sharon Water Department | Sharon, MA | 17,232 |
| Shrewsbury Water Department | Shrewsbury, MA | 35,608 |
| Somerset Water Department | Somerset, MA | 18,257 |
| Somerville Water Department (MWRA) | Somerville, MA | 81,322 |
| South Hadley FD #1 (MWRA) | South Hadley, MA | 14,000 |
| Southborough DPW Water Division (MWRA) | Southborough, MA | 10,401 |
| Southbridge Water Department | Southbridge, MA | 15,287 |
| Springfield Water and Sewer Commission | Springfield, MA | 230,331 |
| Stoneham Water Department (MWRA Supply) | Stoneham, MA | 21,437 |
| Stoughton Water Department (MWRA) | Stoughton, MA | 26,962 |
| Sudbury Water District | Sudbury, MA | 18,410 |
| Swampscott Water Department (MWRA) | Swampscott, MA | 13,787 |
| Swansea Water District | Swansea, MA | 17,358 |
| Taunton Water Division | Taunton, MA | 58,088 |
| Tewksbury Water Department | Tewksbury, MA | 30,435 |
| Uxbridge DPW Water Division | Uxbridge, MA | 10,715 |
| Wakefield Water Department (MWRA) | Wakefield, MA | 24,932 |
| Walpole Water Department | Walpole, MA | 23,989 |
| Waltham Water Department (MWRA) | Waltham, MA | 60,630 |
| Wannacomet Water Company | Nantucket, MA | 27,703 |
| Wareham Fire District | Wareham, MA | 20,830 |
| Watertown Water Department (MWRA) | Watertown, MA | 31,915 |
| Wayland Water Department | Wayland, MA | 14,430 |
| Webster Water Department | Webster, MA | 16,767 |
| Weir River Water System | Hingham, MA | 41,082 |
| Wellesley Water Division (MWRA) | Wellesley, MA | 29,100 |
| West Springfield Dpw Water Division | West Springfield, MA | 28,391 |
| Westborough Water Department | Westborough, MA | 18,272 |
| Westfield Water Department | Westfield, MA | 42,000 |
| Westford Water Department | Westford, MA | 18,000 |
| Weston Water Department (MWRA) | Weston, MA | 11,486 |
| Weymouth Water Department | Weymouth, MA | 53,925 |
| Whitman Water System | Whitman, MA | 14,574 |
| Wilmington Water Department | Wilmington, MA | 22,325 |
| Winchester Water Department (MWRA) | Winchester, MA | 22,800 |
| Winthrop Water Division, (MWRA) | Winthrop, MA | 17,497 |
| Woburn Water Department (MWRA) | Woburn, MA | 38,120 |
| Worcester Department of Public Works | Worcester, MA | 181,045 |
| Wrentham Water Division | Wrentham, MA | 11,686 |
| Yarmouth Water Department | West Yarmouth, MA | 39,635 |
