Systems reaching a study comparison level
26.9%67 of 249 active community water systems with complete monitoring
All 249 systems had complete monitoring. 67 reached at least one study comparison level; 182 did not. “Study comparison level” means the dated EPA technical cutoff used in this January 2026 research release. It does not determine household exposure, health risk, or current legal compliance.
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ZIP codes are used only to route visitors to public water systems that reported serving them. Confirm the actual provider using a water bill or utility record.
Compound summary
System counts in Massachusetts
Each count shows how many included water systems reached the named study level.
| Study comparison | Systems reaching level | Water systems included | Percent |
|---|---|---|---|
| PFOA: study level 4.05 ppt (April 2024 EPA level: 4 ppt) | 61 | 249 | 24.5% |
| PFOS: study level 4.05 ppt (April 2024 EPA level: 4 ppt) | 39 | 249 | 15.7% |
| PFHxS: study level 15 ppt (April 2024 EPA level: 10 ppt) | 2 | 249 | 0.8% |
| PFNA: study level 15 ppt (April 2024 EPA level: 10 ppt) | 0 | 249 | 0.0% |
| HFPO-DA: study level 15 ppt (April 2024 EPA level: 10 ppt) | 0 | 249 | 0.0% |
| Hazard Index: study level 1.5 with at least two detected components (April 2024 EPA level: 1) | 2 | 249 | 0.8% |
System directory
Community water systems with complete monitoring
Each PWSID appears once, preventing double counting across ZIP associations.
| Public water system | PWSID | Population served | Primary source | Sampling locations | Study comparison |
|---|---|---|---|---|---|
| ABINGTON/ROCKLAND JOINT WTR. WORKS | MA4001000 | 33,387 | Surface water | 3 | Reached a study level |
| ACTON WATER SUPPLY DISTRICT | MA2002000 | 21,285 | Groundwater under influence of surface water | 3 | Reached a study level |
| ACUSHNET WATER DEPARTMENT | MA4003000 | 8,430 | Surface water purchased | 1 | Below the study levels |
| ADAMS FIRE DISTRICT | MA1004000 | 7,945 | Ground water | 1 | Below the study levels |
| AGAWAM WATER DEPARTMENT | MA1005000 | 28,692 | Surface water purchased | 1 | Below the study levels |
| AMHERST DPW WATER DIVISION | MA1008000 | 39,263 | Surface water | 5 | Below the study levels |
| ANDOVER WATER DEPT | MA3009000 | 36,569 | Surface water | 1 | Below the study levels |
| AQUARION WATER COMPANY OXFORD | MA2226000 | 7,384 | Ground water | 3 | Below the study levels |
| AQUARION WATER COMPANY, MILLBURY | MA2186000 | 11,368 | Surface water purchased | 3 | Reached a study level |
| ARLINGTON WATER DEPT. (MWRA) | MA3010000 | 46,308 | Surface water purchased | 1 | Below the study levels |
| ASH/WIN JOINT WATER AUTHORITY | MA2011004 | 11,394 | Surface water | 1 | Below the study levels |
| ASHBURNHAM WATER DEPARTMENT | MA2011000 | 3,680 | Surface water purchased | 1 | Below the study levels |
| ATHOL DPW WATER DIVISION | MA1015000 | 10,587 | Ground water | 2 | Below the study levels |
| ATTLEBORO WATER DEPT | MA4016000 | 46,461 | Surface water | 2 | Below the study levels |
| AUBURN WATER DISTRICT, MA | MA2017000 | 12,255 | Surface water purchased | 6 | Reached a study level |
| AYER DPW WATER DIVISION | MA2019000 | 8,479 | Ground water | 2 | Below the study levels |
| Ashland Water & Sewer Dept. | MA3014000 | 18,832 | Ground water | 1 | Below the study levels |
| BARNSTABLE FIRE DISTRICT | MA4020000 | 5,400 | Ground water | 3 | Reached a study level |
| BARRE WATER DEPARTMENT | MA2021000 | 2,610 | Ground water | 3 | Below the study levels |
| BEDFORD WATER DEPT. | MA3023000 | 14,955 | Surface water purchased | 1 | Below the study levels |
| BELCHERTOWN WATER DISTRICT | MA1024000 | 3,253 | Ground water | 2 | Below the study levels |
| BELLINGHAM DPW WATER SEWER DIV. | MA2025000 | 16,556 | Ground water | 2 | Below the study levels |
| BELMONT WATER DEPT. (MWRA) | MA3026000 | 27,442 | Surface water purchased | 1 | Below the study levels |
| BEVERLY WATER DEPT | MA3030000 | 47,461 | Surface water purchased | 1 | Below the study levels |
| BILLERICA WATER WORKS | MA3031000 | 42,119 | Surface water | 1 | Below the study levels |
| BLACKSTONE WATER DEPARTMENT | MA2032000 | 9,463 | Ground water | 1 | Below the study levels |
| BOSTON WATER AND SEWER COMMISSION (MWRA) | MA3035000 | 675,647 | Surface water purchased | 1 | Below the study levels |
| BOURNE WATER DISTRICT | MA4036000 | 22,500 | Ground water | 7 | Below the study levels |
| BRAINTREE WATER AND SEWER DEPT. | MA4040000 | 39,143 | Surface water | 1 | Reached a study level |
| BREWSTER WATER DEPARTMENT | MA4041000 | 35,000 | Ground water | 5 | Below the study levels |
| BRIDGEWATER WATER DEPARTMENT | MA4042000 | 28,633 | Ground water | 3 | Reached a study level |
| BROCKTON WATER DEPARTMENT | MA4044000 | 105,788 | Surface water | 1 | Below the study levels |
| BROOKLINE WATER AND SEWER DIVISION | MA3046000 | 63,191 | Surface water purchased | 1 | Below the study levels |
| BURLINGTON WATER DEPT | MA3048000 | 25,864 | Surface water | 2 | Below the study levels |
| BUZZARDS BAY WATER DISTRICT | MA4036001 | 7,700 | Ground water | 5 | Below the study levels |
| CAMBRIDGE WATER DEPARTMENT | MA3049000 | 118,214 | Surface water | 1 | Below the study levels |
| CANTON WATER DEPT | MA4050000 | 22,766 | Surface water purchased | 3 | Reached a study level |
| CENTERVILLE OSTERVILLE MARSTONS MILLS WD | MA4020002 | 50,000 | Ground water | 15 | Reached a study level |
| CHATHAM WATER DEPARTMENT | MA4055000 | 30,000 | Ground water | 5 | Below the study levels |
| CHELMSFORD WATER DISTRICT | MA3056000 | 28,750 | Ground water | 4 | Reached a study level |
| CHELSEA WATER DEPT. (MWRA) | MA3057000 | 40,787 | Surface water purchased | 1 | Below the study levels |
| CHERRY VALLEY/ ROCHDALE WATER DISTRICT | MA2151001 | 3,696 | Surface water purchased | 2 | Below the study levels |
| CHICOPEE WATER DEPT (MWRA) | MA1061000 | 55,560 | Surface water purchased | 1 | Below the study levels |
| CITY OF NEW BEDFORD DPI | MA4201000 | 101,079 | Surface water | 1 | Below the study levels |
| CLINTON WATER DEPT | MA2064000 | 15,428 | Surface water | 1 | Below the study levels |
| CONCORD WATER DEPT, MA | MA3067000 | 18,788 | Surface water | 6 | Reached a study level |
| COTUIT FIRE DISTRICT WATER DEPARTMENT | MA4020003 | 4,938 | Ground water | 5 | Below the study levels |
| DANVERS WATER DEPT. | MA3071000 | 28,087 | Surface water | 2 | Below the study levels |
| DARTMOUTH WATER DIVISION | MA4072000 | 24,696 | Surface water purchased | 4 | Reached a study level |
| DEDHAM WESTWOOD WATER DIST. | MA3073000 | 41,630 | Surface water purchased | 3 | Reached a study level |
| DENNIS WATER DISTRICT | MA4075000 | 65,000 | Ground water | 9 | Below the study levels |
| DEVENS MASSDEVELOPMENT | MA2019001 | 6,500 | Ground water | 3 | Below the study levels |
| DIGHTON WATER DISTRICT | MA4076000 | 5,280 | Surface water purchased | 1 | Below the study levels |
| DRACUT WATER SUPPLY DISTRICT | MA3079000 | 25,808 | Surface water purchased | 3 | Reached a study level |
| DUDLEY WATER DEPARTMENT | MA2080000 | 5,515 | Ground water | 1 | Below the study levels |
| DUXBURY WATER DEPARTMENT | MA4082000 | 16,387 | Ground water | 8 | Reached a study level |
| EAST LONGMEADOW DPW WATER DEPT | MA1085000 | 16,358 | Surface water purchased | 1 | Below the study levels |
| EASTHAMPTON WATER DEPT | MA1087000 | 16,211 | Ground water | 4 | Below the study levels |
| EASTON WATER DIV | MA4088000 | 25,058 | Ground water | 4 | Reached a study level |
| EDGARTOWN WATER DEPARTMENT | MA4089000 | 8,027 | Ground water | 5 | Below the study levels |
| EVERETT WATER DEPT. (MWRA) | MA3093000 | 49,075 | Surface water purchased | 1 | Below the study levels |
| East Bridgewater Water Dept. | MA4083000 | 14,526 | Ground water | 2 | Reached a study level |
| FALL RIVER WATER DEPARTMENT | MA4095000 | 94,000 | Surface water | 1 | Below the study levels |
| FALMOUTH WATER DEPT | MA4096000 | 97,551 | Surface water | 4 | Below the study levels |
| FITCHBURG DPW, DIV. OF WATER SUPPLY | MA2097000 | 41,946 | Surface water | 2 | Below the study levels |
| FOXBORO WATER DEPARTMENT | MA4099000 | 18,721 | Ground water | 3 | Reached a study level |
| FRAMINGHAM WATER DEPT. (MWRA) | MA3100000 | 72,362 | Surface water purchased | 1 | Below the study levels |
| FRANKLIN WATER DEPARTMENT, MA | MA2101000 | 33,706 | Ground water | 7 | Reached a study level |
| GARDNER WATER DEPARTMENT | MA2103000 | 21,381 | Surface water | 2 | Below the study levels |
| GEORGETOWN WATER DEPARTMENT | MA3105000 | 8,766 | Ground water | 1 | Below the study levels |
| GLOUCESTER PUBLIC UTILITY DIVISION | MA3107000 | 37,440 | Surface water | 2 | Below the study levels |
| GRAFTON WATER DISTRICT | MA2110000 | 10,925 | Ground water | 4 | Reached a study level |
| GREAT BARRINGTON FIRE DIST | MA1113000 | 4,380 | Ground water | 1 | Below the study levels |
| GREENFIELD WATER DEPARTMENT | MA1114000 | 17,768 | Surface water | 2 | Below the study levels |
| GROTON WATER DEPARTMENT | MA2115000 | 5,456 | Ground water | 2 | Below the study levels |
| GROVELAND WATER DEPARTMENT | MA3116000 | 6,508 | Ground water | 2 | Reached a study level |
| HADLEY DPW WATER DIVISION | MA1117002 | 4,819 | Ground water | 2 | Below the study levels |
| HALIFAX WATER DEPARTMENT | MA4118000 | 7,575 | Surface water purchased | 4 | Below the study levels |
| HAMILTON WATER DEPT | MA3119000 | 7,674 | Ground water | 2 | Reached a study level |
| HANOVER WATER DEPT, MA | MA4122000 | 14,984 | Groundwater under influence of surface water | 3 | Reached a study level |
| HANSCOM AFB | MA3023002 | 11,789 | Surface water purchased | 2 | Below the study levels |
| HANSON WATER DEPARTMENT | MA4123000 | 9,612 | Surface water purchased | 1 | Reached a study level |
| HARWICH WATER DEPARTMENT | MA4126000 | 39,144 | Ground water | 5 | Below the study levels |
| HATFIELD WATER DEPT | MA1127000 | 3,164 | Surface water | 3 | Below the study levels |
| HAVERHILL WATER DEPT | MA3128000 | 61,277 | Surface water | 1 | Below the study levels |
| HAYSTACK ESTATES | MA3330019 | 60 | Ground water | 1 | Reached a study level |
| HOLBROOK PUBLIC WORKS DEPT | MA4133000 | 11,405 | Surface water purchased | 1 | Reached a study level |
| HOLDEN WATER DIVISION, DPW | MA2134000 | 18,016 | Surface water purchased | 4 | Reached a study level |
| HOLLISTON WATER DEPARTMENT | MA2136000 | 15,139 | Ground water | 3 | Reached a study level |
| HOLYOKE WATER WORKS | MA1137000 | 37,838 | Surface water | 2 | Below the study levels |
| HOPEDALE WATER DEPARTMENT | MA2138000 | 6,017 | Surface water purchased | 1 | Reached a study level |
| HOPKINTON WATER DEPARTMENT | MA2139000 | 12,680 | Ground water | 4 | Reached a study level |
| HUDSON WATER SUPPLY | MA2141000 | 20,032 | Surface water | 2 | Below the study levels |
| HYANNIS WATER SYSTEM, TOWN OF BARNSTABLE | MA4020004 | 35,000 | Ground water | 3 | Below the study levels |
| INIMA USA / AQUARIA LLC | MA4076004 | 105,643 | Surface water | 1 | Below the study levels |
| IPSWICH DPU WATER DEPT | MA3144000 | 13,138 | Surface water | 5 | Reached a study level |
| KENWOOD WATER DISTRICT | MA3079001 | 9,620 | Surface water purchased | 2 | Below the study levels |
| LANCASTER WATER DEPARTMENT | MA2147000 | 6,000 | Ground water | 2 | Below the study levels |
| LAWRENCE WATER WORKS | MA3149000 | 89,143 | Surface water | 1 | Below the study levels |
| LEE WATER DEPT | MA1150000 | 5,686 | Surface water | 1 | Below the study levels |
| LENOX DPW WATER DIVISION | MA1152000 | 9,800 | Surface water | 1 | Below the study levels |
| LEOMINSTER WATER DIVISION | MA2153000 | 41,683 | Surface water | 4 | Below the study levels |
| LEXINGTON WATER DEPT. (MWRA) | MA3155000 | 34,074 | Surface water purchased | 1 | Below the study levels |
| LINCOLN WATER DEPT | MA3157000 | 5,593 | Surface water | 2 | Reached a study level |
| LITTLETON WATER DEPARTMENT | MA2158000 | 9,307 | Ground water | 1 | Below the study levels |
| LONGMEADOW WATER DEPT | MA1159000 | 15,853 | Surface water purchased | 1 | Below the study levels |
| LOWELL REGIONAL WATER UTILITY | MA3160000 | 120,418 | Surface water | 1 | Below the study levels |
| LUNENBURG WATER DISTRICT | MA2162000 | 7,219 | Ground water | 2 | Below the study levels |
| LYNN WATER AND SEWER COMM | MA3163000 | 101,253 | Surface water | 1 | Below the study levels |
| LYNNFIELD CENTER WATER DISTRICT | MA3164000 | 8,525 | Surface water purchased | 3 | Reached a study level |
| MALDEN WATER DIVISION (MWRA) | MA3165000 | 66,263 | Surface water purchased | 1 | Below the study levels |
| MANCHESTER BY THE SEA DPW | MA3166000 | 5,201 | Surface water | 2 | Reached a study level |
| MANSFIELD WATER DIVISION | MA4167000 | 21,797 | Ground water | 3 | Below the study levels |
| MARBLEHEAD WATER DEPT. (MWRA) | MA3168000 | 20,441 | Surface water purchased | 1 | Below the study levels |
| MARION WATER DIVISION | MA4169000 | 6,119 | Ground water | 1 | Below the study levels |
| MARLBOROUGH DPW WATER DIV. (MWRA) | MA2170000 | 41,799 | Surface water purchased | 1 | Below the study levels |
| MARSHFIELD WATER DEPARTMENT | MA4171000 | 34,000 | Ground water | 16 | Reached a study level |
| MASHPEE WATER DISTRICT | MA4172039 | 36,922 | Ground water | 6 | Below the study levels |
| MATTAPOISETT RIVER VALLEY W.D. | MA4173001 | 29,600 | Ground water purchased | 2 | Below the study levels |
| MATTAPOISETT WATER DEPARTMENT | MA4173000 | 7,685 | Ground water | 1 | Below the study levels |
| MAYNARD DPW, WATER DIVISION | MA2174000 | 10,616 | Ground water | 3 | Reached a study level |
| MCI NORFOLK/CEDAR JUNCTION/WALPOLE | MA2208001 | 2,200 | Ground water | 1 | Below the study levels |
| MCI SHIRLEY | MA2270001 | 3,500 | Ground water | 1 | Below the study levels |
| MEDFIELD WATER DEPT. | MA2175000 | 12,713 | Ground water | 3 | Reached a study level |
| MEDFORD WATER DEPT. (MWRA) | MA3176000 | 61,700 | Surface water purchased | 1 | Below the study levels |
| MEDWAY WATER DEPARTMENT | MA2177000 | 14,176 | Ground water | 2 | Reached a study level |
| MELROSE WATER DIVISION (MWRA) | MA3178000 | 29,938 | Surface water purchased | 1 | Below the study levels |
| MERRIMAC WATER DEPARTMENT | MA3180000 | 6,988 | Ground water | 2 | Reached a study level |
| METHUEN WATER DEPT | MA3181000 | 53,059 | Surface water | 1 | Below the study levels |
| MIDDLEBOROUGH WATER SUPPLY | MA4182000 | 15,350 | Ground water | 10 | Reached a study level |
| MIDDLETON WATER DEPT. | MA3184000 | 7,291 | Surface water purchased | 1 | Below the study levels |
| MILFORD WATER COMPANY | MA2185000 | 30,379 | Surface water | 2 | Reached a study level |
| MILLIS WATER DEPT | MA2187000 | 9,055 | Ground water | 4 | Reached a study level |
| MILTON WATER DEPT. (MWRA) | MA3189000 | 28,630 | Surface water purchased | 1 | Below the study levels |
| MONSON WATER AND SEWER DEPT | MA1191000 | 4,222 | Ground water | 3 | Below the study levels |
| NAHANT WATER DEPT. (MWRA) | MA3196000 | 3,334 | Surface water purchased | 1 | Below the study levels |
| NATICK WATER DEPARTMENT | MA3198000 | 37,006 | Ground water | 4 | Reached a study level |
| NEEDHAM WATER DEPT | MA3199000 | 31,664 | Surface water purchased | 2 | Reached a study level |
| NEWBURYPORT WATER DEPARTMENT | MA3206000 | 20,335 | Surface water | 2 | Below the study levels |
| NEWTON WATER DEPT. (MWRA) | MA3207000 | 88,931 | Surface water purchased | 1 | Below the study levels |
| NORFOLK WATER DIVISION | MA2208000 | 7,602 | Ground water | 4 | Reached a study level |
| NORTH ADAMS WATER DEPT | MA1209000 | 13,000 | Surface water | 1 | Below the study levels |
| NORTH ANDOVER WATER DEPT | MA3210000 | 30,915 | Surface water | 1 | Below the study levels |
| NORTH ATTLEBORO WATER DEPT | MA4211000 | 31,410 | Ground water | 4 | Reached a study level |
| NORTH BROOKFIELD WATER DEPARTMENT | MA2212000 | 3,863 | Surface water | 1 | Below the study levels |
| NORTH CHELMSFORD WATER DIST | MA3056002 | 7,660 | Ground water | 1 | Below the study levels |
| NORTH RAYNHAM WATER DISTRICT | MA4245002 | 3,902 | Ground water | 2 | Below the study levels |
| NORTH READING WATER DEPT. | MA3213000 | 16,379 | Surface water purchased | 1 | Below the study levels |
| NORTH SAGAMORE WATER DISTRICT | MA4036002 | 4,668 | Ground water | 2 | Below the study levels |
| NORTHAMPTON WATER DEPT | MA1214000 | 29,571 | Surface water | 3 | Below the study levels |
| NORTHBOROUGH WATER DEPARTMENT (MWRA) | MA2215000 | 13,551 | Surface water purchased | 1 | Below the study levels |
| NORTHBRIDGE WATER DIVISION | MA2216006 | 8,127 | Purchased ground water under influence of surface water source | 1 | Below the study levels |
| NORTON WATER DEPARTMENT | MA4218000 | 19,161 | Ground water | 3 | Reached a study level |
| NORWELL WATER DEPARTMENT | MA4219000 | 11,495 | Ground water | 3 | Reached a study level |
| NORWOOD WATER DEPT. (MWRA) | MA4220000 | 29,909 | Surface water purchased | 1 | Below the study levels |
| OAK BLUFFS WATER DISTRICT | MA4221000 | 24,000 | Ground water | 5 | Below the study levels |
| ORANGE WATER DEPT | MA1223000 | 6,526 | Surface water purchased | 4 | Below the study levels |
| ORLEANS WATER DEPARTMENT | MA4224000 | 17,460 | Ground water | 2 | Below the study levels |
| OTIS AIR NATIONAL GUARD BASE | MA4096001 | 6,000 | Ground water | 1 | Below the study levels |
| PALMER WATER DISTRICT NO.1 | MA1227000 | 4,789 | Surface water | 3 | Below the study levels |
| PAXTON WATER DEPARTMENT | MA2228000 | 4,300 | Surface water purchased | 1 | Below the study levels |
| PEABODY WATER DEPT. | MA3229000 | 54,481 | Surface water | 3 | Reached a study level |
| PEMBROKE WATER DIVISION DPW | MA4231000 | 18,175 | Ground water | 3 | Below the study levels |
| PEPPERELL DPW WATER DIVISION | MA2232000 | 9,217 | Ground water | 3 | Reached a study level |
| PINEHILLS WATER COMPANY, INC. | MA4239055 | 9,478 | Ground water | 1 | Below the study levels |
| PITTSFIELD DPU WATER DEPT | MA1236000 | 43,927 | Surface water | 2 | Below the study levels |
| PLAINVILLE WATER DEPARTMENT | MA4238000 | 8,805 | Groundwater under influence of surface water | 2 | Reached a study level |
| PLYMOUTH WATER DEPARTMENT, MA | MA4239000 | 47,100 | Ground water | 11 | Below the study levels |
| PROVINCETOWN WATER DEPARTMENT | MA4242000 | 22,250 | Ground water | 2 | Below the study levels |
| QUINCY WATER DEPT. (MWRA) | MA3243000 | 106,000 | Surface water purchased | 1 | Below the study levels |
| RANDOLPH WATER DEPARTMENT | MA4244000 | 35,114 | Surface water purchased | 1 | Reached a study level |
| RAYNHAM CENTER WATER DISTRICT | MA4245000 | 10,964 | Ground water | 3 | Reached a study level |
| READING WATER DEPARTMENT | MA3246000 | 26,262 | Surface water purchased | 1 | Below the study levels |
| REVERE WATER DIVISION (MWRA) | MA3248000 | 62,186 | Surface water purchased | 1 | Below the study levels |
| ROCKPORT WATER DEPT | MA3252000 | 10,000 | Surface water | 1 | Below the study levels |
| ROWLEY WATER DEPARTMENT | MA3254000 | 6,161 | Ground water | 2 | Reached a study level |
| RUTLAND WATER DEPARTMENT | MA2257000 | 6,025 | Surface water | 2 | Below the study levels |
| SALEM WATER DEPARTMENT, MA | MA3258000 | 44,480 | Surface water purchased | 1 | Below the study levels |
| SANDWICH WATER DISTRICT | MA4261000 | 23,000 | Ground water | 10 | Below the study levels |
| SAUGUS WATER DEPT. (MWRA) | MA3262000 | 27,844 | Surface water purchased | 1 | Below the study levels |
| SCITUATE WATER DIVISION | MA4264000 | 19,297 | Surface water | 4 | Reached a study level |
| SEEKONK WATER DISTRICT | MA4265000 | 13,801 | Ground water | 1 | Reached a study level |
| SHARON WATER DEPT | MA4266000 | 16,846 | Ground water | 6 | Reached a study level |
| SHIRLEY WATER DISTRICT | MA2270000 | 4,165 | Ground water | 3 | Below the study levels |
| SHREWSBURY WATER DEPARTMENT | MA2271000 | 38,325 | Ground water | 1 | Below the study levels |
| SOMERSET WATER DEPARTMENT | MA4273000 | 18,303 | Surface water | 1 | Below the study levels |
| SOMERVILLE WATER DEPT. (MWRA) | MA3274000 | 81,045 | Surface water purchased | 1 | Below the study levels |
| SOUTH DEERFIELD WATER SUPPLY DISTRICT | MA1074001 | 3,800 | Surface water | 1 | Below the study levels |
| SOUTH HADLEY FD #1 (MWRA) | MA1275000 | 14,800 | Surface water purchased | 1 | Below the study levels |
| SOUTH HADLEY FIRE DISTRICT #2 WATER DEPT | MA1275001 | 6,200 | Ground water | 2 | Below the study levels |
| SOUTHAMPTON WATER DEPT | MA1276000 | 4,853 | Purchased ground water under influence of surface water source | 2 | Below the study levels |
| SOUTHBOROUGH DPW WATER DIVISION (MWRA) | MA2277000 | 10,638 | Surface water purchased | 1 | Below the study levels |
| SOUTHBRIDGE WATER DEPARTMENT | MA2278000 | 19,562 | Surface water | 1 | Below the study levels |
| SOUTHWICK WATER DEPT | MA1279000 | 7,669 | Surface water purchased | 2 | Below the study levels |
| SPENCER WATER DEPARTMENT | MA2280000 | 7,037 | Ground water | 2 | Below the study levels |
| SPRINGFIELD WATER AND SEWER COMMISSION | MA1281000 | 169,170 | Surface water | 1 | Below the study levels |
| STERLING WATER DEPARTMENT | MA2282000 | 6,715 | Ground water | 2 | Below the study levels |
| STONEHAM WATER DEPT (MWRA SUPPLY) | MA3284000 | 23,244 | Surface water purchased | 1 | Below the study levels |
| STURBRIDGE WATER DEPARTMENT | MA2287000 | 4,746 | Groundwater under influence of surface water | 2 | Below the study levels |
| SUDBURY WATER DISTRICT | MA3288000 | 18,416 | Ground water | 5 | Reached a study level |
| SWAMPSCOTT WATER DEPT. (MWRA) | MA3291000 | 15,300 | Surface water purchased | 1 | Below the study levels |
| SWANSEA WATER DISTRICT | MA4292000 | 17,375 | Surface water | 4 | Below the study levels |
| TAUNTON WATER DIVISION | MA4293000 | 62,165 | Surface water | 1 | Below the study levels |
| TEMPLETON MUNIC. LIGHT AND WATER PLANT | MA2294000 | 6,159 | Ground water | 4 | Reached a study level |
| TEWKSBURY WATER DEPARTMENT | MA3295000 | 31,342 | Surface water | 1 | Below the study levels |
| TISBURY WATER WORKS | MA4296000 | 6,082 | Ground water | 3 | Below the study levels |
| TOPSFIELD WATER DEPARTMENT | MA3298000 | 5,435 | Ground water | 1 | Reached a study level |
| TOWN OF AVON | MA4018000 | 4,777 | Ground water | 2 | Reached a study level |
| TOWN OF EASTHAM | MA4086095 | 6,199 | Ground water | 2 | Below the study levels |
| TOWNSEND WATER DEPARTMENT | MA2299000 | 6,832 | Ground water | 5 | Below the study levels |
| TURNERS FALLS WATER DEPT | MA1192000 | 8,080 | Ground water | 2 | Below the study levels |
| TYNGSBOROUGH WATER DISTRICT | MA3301000 | 4,416 | Surface water purchased | 2 | Below the study levels |
| UPPER CAPE REGIONAL WATER COOPERATIVE | MA4261024 | 56,250 | Ground water | 3 | Below the study levels |
| UPTON DPW WATER/WASTEWATER DIVISION | MA2303000 | 4,420 | Ground water | 3 | Below the study levels |
| UXBRIDGE DPW, WATER DIVISION | MA2304000 | 11,612 | Ground water | 3 | Reached a study level |
| WAKEFIELD WATER DEPT | MA3305000 | 27,090 | Surface water | 2 | Below the study levels |
| WALPOLE WATER DEPT | MA4307000 | 24,070 | Ground water | 2 | Below the study levels |
| WALTHAM WATER DEPARTMENT | MA3308000 | 65,218 | Surface water purchased | 1 | Below the study levels |
| WARE WATER DEPT | MA1309000 | 10,066 | Ground water | 2 | Reached a study level |
| WAREHAM FIRE DISTRICT | MA4310000 | 20,102 | Ground water | 2 | Below the study levels |
| WATERTOWN WATER DEPT. (MWRA) | MA3314000 | 35,985 | Surface water purchased | 1 | Below the study levels |
| WAYLAND WATER DEPARTMENT | MA3315000 | 14,096 | Ground water | 4 | Reached a study level |
| WEBSTER WATER DEPARTMENT | MA2316000 | 17,776 | Ground water | 2 | Below the study levels |
| WEIR RIVER WATER SYSTEM | MA4131000 | 45,339 | Surface water | 2 | Below the study levels |
| WELLESLEY WATER DIVISION | MA3317000 | 29,550 | Surface water purchased | 4 | Reached a study level |
| WENHAM WATER DEPT. | MA3320000 | 3,942 | Ground water | 1 | Reached a study level |
| WEST BOYLSTON WATER DISTRICT | MA2321000 | 6,919 | Surface water purchased | 4 | Below the study levels |
| WEST BRIDGEWATER WATER DEPT | MA4322000 | 7,709 | Ground water | 4 | Below the study levels |
| WEST NEWBURY WATER DEPARTMENT | MA3324000 | 4,704 | Surface water purchased | 1 | Below the study levels |
| WEST SPRINGFIELD DPW WATER DIVISION | MA1325000 | 28,835 | Ground water | 1 | Below the study levels |
| WESTBOROUGH WATER DEPARTMENT | MA2328000 | 21,567 | Surface water | 5 | Below the study levels |
| WESTFIELD WATER DEPT | MA1329000 | 41,094 | Surface water | 6 | Below the study levels |
| WESTFORD WATER DEPARTMENT | MA3330000 | 18,848 | Groundwater under influence of surface water | 2 | Below the study levels |
| WESTMINSTER DEPARTMENT OF PUBLIC WORKS | MA2332000 | 3,889 | Surface water purchased | 1 | Below the study levels |
| WESTON WATER DEPT. | MA3333000 | 11,391 | Surface water purchased | 1 | Below the study levels |
| WEYMOUTH WATER DEPARTMENT | MA4336000 | 57,871 | Surface water | 2 | Below the study levels |
| WHATELY WATER DEPARTMENT | MA1337010 | 900 | Ground water | 1 | Below the study levels |
| WHITINSVILLE WATER COMPANY | MA2216000 | 7,899 | Groundwater under influence of surface water | 2 | Below the study levels |
| WHITMAN WATER SYSTEM | MA4338000 | 14,947 | Surface water purchased | 1 | Below the study levels |
| WILBRAHAM WATER DEPT (MWRA) | MA1339000 | 8,533 | Surface water purchased | 1 | Below the study levels |
| WILLIAMSTOWN WATER DEPT | MA1341000 | 7,326 | Ground water | 3 | Below the study levels |
| WILMINGTON WATER DEPT | MA3342000 | 21,654 | Surface water purchased | 3 | Below the study levels |
| WINCHENDON WATER DEPARTMENT | MA2343000 | 5,706 | Surface water purchased | 1 | Below the study levels |
| WINCHESTER WATER DEPT | MA3344000 | 22,970 | Surface water | 2 | Below the study levels |
| WINTHROP WATER DIVISION, (MWRA) | MA3346000 | 19,316 | Surface water purchased | 1 | Below the study levels |
| WOBURN WATER DEPT. | MA3347000 | 40,876 | Surface water purchased | 2 | Reached a study level |
| WORCESTER DPWP, WATER SUPPLY DIVISION | MA2348000 | 206,518 | Surface water | 1 | Below the study levels |
| WRENTHAM WATER DIVISION | MA4350000 | 12,190 | Ground water | 3 | Below the study levels |
| YARMOUTH WATER DEPARTMENT | MA4351000 | 38,900 | Ground water | 15 | Below the study levels |
How the count works
What is included
Each active community water system with complete monitoring is counted once, even if it is linked with several ZIP codes. Private wells are excluded, and UCMR 5 did not comprehensively monitor every small system. This page does not apply Massachusetts's state-specific standards or determine compliance. Use the official state or territory drinking-water program for current regulatory information.