The Power of Information

National Drinking Water Database


494 systems serving 7,695,428 people

This drinking water quality report shows results of tests conducted by water utilities in Massachusetts, provided to the Environmental Working Group (EWG) by the Massachusetts Department of Environmental Protection. It is part of EWG's national database that includes 47,667 drinking water utilities and 20 million test results from 45 states and the District of Columbia. Water utilities nationwide detected more than 300 pollutants between 2004 and 2009. More than half of these chemicals are unregulated, legal in any amount. Despite this widespread contamination, the federal government invests few resources in protecting rivers, reservoirs, and groundwater from pollution in the first place. The information below summarizes drinking water quality for this state.

Water Utilities
Population Served
Detected Chemicals
Exceed health guidelines*
Exceed Legal Limits*
Unregulated chemicals detected
* Water utilities are noted as exceeding the legal limit if any test is above the maximum contaminant level (MCL). Most MCLs are based on annual averages so exceeding the MCL for one test does not necessarily indicate that the system is out of compliance.

46 Contaminants Exceeding Health Based Limits

Contaminants detected in Massachusetts drinking water above health guidelines, according to an Environmental Working Group analysis of data obtained from state water authorities

Number of Systems
At Any Level Above Health Limits At Any Level Above Health Limits
Total haloacetic acids (HAAs)6,493,1006,426,900232229
Total trihalomethanes (TTHMs)7,057,9396,162,429311207

Water Utilities in Massachusetts Reporting Chemicals Exceeding Health Guidelines

Water utilities in Massachusetts reporting chemicals exceeding health guidelines, according to an Environmental Working Group analysis of data obtained from state water authorities, include:

Chemicals tested
Chemicals found
Chemicals exceeding
health guidelines
Weymouth Water Department52,6321242113
Middleborough Water Supply20,386781612
Maynard Dpw, Water Division10,0371212012
Cherry Valley & Rochdale Water District4,5001251712
Devens Mass Development9,4221241612
Auburn Water District9,9001242112
Walpole Water Dept24,061711511
Braintree Water & Sewer Dept.33,6001231511
Haystack Estates751241311
Westford Water Department15,8531272011
Chelmsford Water District25,3931201511
Burlington Water Dept23,3011212311
Aquarion Water Company: Millbury8,9061222611
Leicester Water Supply District3,300811511
Grafton Water District9,8001161911
Hingham/Hull Aquarion Water Co43,7361221510
Hanover Water Dept13,727701410
Dartmouth Water Div.30,0001231310
East Chelmsford Water District2,0001212010
Assabet Water Company/Harvard Acres750621510

Sources of Massachusetts Drinking Water Contaminants

The contaminants identified in Massachusetts drinking water come from a wide variety of sources, including agriculture, industry, water treatment plants, and polluted storm runoff from urban areas.

94Total Contaminants Detected (2004 - 2009)
29Agricultural Pollutants
(pesticides, fertilizer, factory farms)

Arsenic (total), Cyanide, Nitrate, Nitrite, Selenium (total), Endrin, Lindane, Methoxychlor, Toxaphene, Carbaryl, Dalapon, Endothall, Oxamyl (Vydate), Picloram, Dinoseb, Metolachlor, Atrazine, 2,4-D, Bromomethane, Aldrin, Dicamba, 1,2-Dibromo-3-chloropropane (DBCP), Ethylene dibromide (EDB), o-Dichlorobenzene, p-Dichlorobenzene, 1,2-Dichloropropane, Monochlorobenzene (Chlorobenzene), Ethylbenzene, Perchlorate

24Sprawl and Urban Pollutants
(road runoff, lawn pesticides, human waste)

Nitrate, Copper, Lead (total), Arsenic (total), Tetrachloroethylene, MTBE, Nitrite, Xylenes (total), Dalapon, Cadmium (total), Antimony (total), Mercury (total inorganic), Dichloromethane (methylene chloride), Cyanide, Benzene, Trichlorofluoromethane, p-Dichlorobenzene, Di(2-Ethylhexyl) adipate, 2,4-D, Naphthalene, Benzo[a]pyrene, Lindane, Bromobenzene, Carbaryl

67Industrial Pollutants

Aluminum, Bromide, Arsenic (total), Chlorite, Barium (total), Cadmium (total), Chromium (total), Cyanide, Lead (total), Manganese, Mercury (total inorganic), Nitrate, Nitrite, Selenium (total), Antimony (total), Beryllium (total), Thallium (total), Asbestos, Lindane, Di(2-Ethylhexyl) adipate, Di(2-ethylhexyl) phthalate, Hexachlorocyclopentadiene, 1,4-Dioxane, Chloromethane, Dichlorodifluoromethane, Chloroethane, Trichlorofluoromethane, Naphthalene, MTBE, 1,2,4-Trichlorobenzene, cis-1,2-Dichloroethylene, Aroclor 1242, Dibromomethane, 1,2,4-Trimethylbenzene, 1,3,5-Trimethylbenzene, Bromochloromethane, Ethylene dibromide (EDB), Xylenes (total), Dichloromethane (methylene chloride), o-Chlorotoluene, p-Chlorotoluene, p-Dichlorobenzene, Vinyl chloride, 1,1-Dichloroethylene, 1,1-Dichloroethane, trans-1,2-Dichloroethylene, 1,2-Dichloroethane, 1,1,1-Trichloroethane, Carbon tetrachloride, 1,2-Dichloropropane, Trichloroethylene, 1,1,1,2-Tetrachloroethane, Tetrachloroethylene, Monochlorobenzene (Chlorobenzene), Benzene, Toluene, Ethylbenzene, Bromobenzene, Isopropylbenzene, Styrene, Alpha particle activity (incl. radon & uranium), Combined Uranium (mg/L), Radium-226, Radium-228, Perchlorate, Combined Uranium (pCi/L), Gross beta particle activity (pCi/L)

17Water Treatment and Distribution Byproducts
(pipes and fixtures, treatment chemicals and byproducts)

Total trihalomethanes (TTHMs), Total haloacetic acids (HAAs), Chloroform, Bromodichloromethane, Dibromochloromethane, Bromoform, Chlorite, Di(2-ethylhexyl) phthalate, Cadmium (total), Chloromethane, Bromate, Vinyl chloride, Asbestos, Dibromomethane, Bromochloromethane, Benzo[a]pyrene, Chloroethane

21Naturally Occurring
(naturally present but increased for lands denuded by sprawl, agriculture, or industrial development)

Nitrate, Copper, Barium (total), Lead (total), Arsenic (total), Manganese, Radium-228, Radium-226, Gross beta particle activity (pCi/L), Combined Uranium (pCi/L), Chromium (total), Alpha particle activity (incl. radon & uranium), Combined Uranium (mg/L), Aluminum, Selenium (total), Nitrite, Radon, Bromide, Mercury (total inorganic), Chloromethane, Cyanide

26Unregulated Contaminants
EPA has not established a maximum legal limit in tapwater for these contaminants

Bromide, Lead (total), Carbaryl, Metolachlor, 1,4-Dioxane, Chloromethane, Dichlorodifluoromethane, Bromomethane, Chloroethane, Trichlorofluoromethane, Naphthalene, MTBE, Aldrin, Dibromomethane, 1,2,4-Trimethylbenzene, 1,3,5-Trimethylbenzene, Bromochloromethane, Dicamba, o-Chlorotoluene, p-Chlorotoluene, 1,1-Dichloroethane, 1,1,1,2-Tetrachloroethane, Bromobenzene, Isopropylbenzene, Radon, Perchlorate

Testing Summary for Massachusetts

The federal government has set standards for some of the pollutants found in tap water supplies.

Contaminants reported as tested by water suppliers in Massachusetts140
 Contaminants tested due to federal law: 88
 Contaminants tested in addition to those required by federal law: 52

Violation Summary for Massachusetts

Data from the U.S. Environmental Protection Agency includes the following violations of federal standards in Massachusetts since 2004

Violation TypeNumber of Violations
Failure to monitor regularly3,154
Maximum contaminant level, Monthly (Coliform bacteria)286
Over maximum contaminant level, Average133
Failure to monitor, Routine Minor (Coliform bacteria)99
Follow-up and Routine Tap Sampling93
Monitoring and Reporting Disinfection Byproduct Rule82
Failure to monitor, Repeat Minor (Coliform bacteria)70
Failure to monitor, Routine Major (Coliform bacteria)62
Failure to monitor or report, Routine/Repeat (Indicators of microbial or virus contamination)31
Maximum contaminant level, Acute (Coliform bacteria)28
Failure to report information to the public or state agency in the Consumer Confidence Report24
Failure to monitor or report, Routine/Repeat (Indicators of microbial or virus contamination)24
Failure to monitor, Repeat Major (Coliform bacteria)19
Failure to notify state agency17
Public Notification Violation for National Primary Drinking Water Regulations14
Treatment Technique (Surface Water Treatment Rule)11
Failure to notify public of violation11
Inadequate reporting of information to the public9
Lead Service Line Replacement7
Initial Water Quality Parameter Monitoring and Reporting6
Treatment Technique Precursor Removal2
Optimal Corrosion Control Treatment Study Recommendation2
Water Quality Program Entry Point Non-Compliance2
Optimal Corrosion Control Treatment Installation/Demonstration2
Other Non-National Primary Drinking Water Regulations Potential Health Risks1
Excess Turbidity at 1 NTU1
Excess Turbidity at 0.3 NTU1