937 systems serving 4,150,414 people
  This drinking water quality report shows results of tests conducted by water utilities in Minnesota, provided to the Environmental Working Group (EWG) by the Minnesota Department of Health- Environmental Health Division. 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.

  32 Contaminants Exceeding Health Based Limits

Contaminants detected in Minnesota 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
Bromodichloromethane 3,880,815 3,880,815 592 592
Dibromochloromethane 3,274,907 3,238,460 385 380
Dichloroacetic acid 3,046,302 3,046,302 424 424
Total trihalomethanes (TTHMs) 3,984,464 2,813,218 697 324
Chloroform 3,982,474 2,586,570 694 298
Alpha particle activity 1,826,886 1,826,886 316 316
Radon 1,223,726 1,223,726 552 552
Bromoform 1,119,917 1,119,917 166 166
Arsenic (total) 1,110,732 1,110,732 304 304
n-Nitrosodimethylamine 797,353 797,353 2 2

  Sources of Minnesota Drinking Water Contaminants

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

94 Total Contaminants Detected (2004 - 2010)
19 Agricultural Pollutants
(pesticides, fertilizer, factory farms)

Nitrate, Arsenic (total), Selenium (total), Nitrite, Atrazine, Ethylbenzene, Dalapon, n-Nitrosodimethylamine, Chlorate, 1,2-Dichloropropane, Metolachlor, p-Dichlorobenzene, DCPA di acid degradate, Phosphorus, 2,4-D, Bromomethane, Monochlorobenzene (Chlorobenzene), o-Dichlorobenzene, Aldicarb sulfoxide

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

Nitrate, Arsenic (total), Tetrachloroethylene, MTBE, Nitrite, Xylenes (total), Dalapon, Cadmium (total), Antimony (total), Mercury (total inorganic), m- & p- Xylene, Dichloromethane (methylene chloride), o-Xylene, Benzene, Acetone, Molybdenum, Trichlorofluoromethane, p-Dichlorobenzene, DCPA di acid degradate, Methyl ethyl ketone, Phosphorus, Lithium, 2,4-D, Naphthalene, n-Propylbenzene, Tin (total)

65 Industrial Pollutants

Bromide, Arsenic (total), Chlorate, Chlorite, Barium (total), Cadmium (total), Chromium (total), Manganese, Mercury (total inorganic), Nitrate, Nitrite, Selenium (total), Strontium, Antimony (total), Beryllium (total), Lithium, Molybdenum, Thallium (total), Tin (total), Phosphorus, Di(2-ethylhexyl) phthalate, Ethyl ether, Chloromethane, Dichlorodifluoromethane, Chloroethane, Trichlorofluoromethane, trans-1,3-Dichloropropene, Acetone, Methyl ethyl ketone, Naphthalene, Methyl isobutyl ketone, MTBE, Tetrahydrofuran, Hexachlorobenzene (HCB), n-Nitrosodimethylamine, cis-1,2-Dichloroethylene, Dibromomethane, 1,2,4-Trimethylbenzene, 1,3,5-Trimethylbenzene, Bromochloromethane, Xylenes (total), Dichloromethane (methylene chloride), 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, Tetrachloroethylene, Monochlorobenzene (Chlorobenzene), Benzene, Toluene, Ethylbenzene, Isopropylbenzene, Styrene, o-Xylene, n-Propylbenzene, m- & p- Xylene, Alpha particle activity, Dichlorofluoromethane, Combined Uranium (pCi/L)

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

Total trihalomethanes (TTHMs), Total haloacetic acids (HAAs), Chloroform, Bromodichloromethane, Dibromochloromethane, Dichloroacetic acid, Trichloroacetic acid, Bromoform, Dibromoacetic acid, Monochloroacetic acid, Bromochloroacetic acid, Monobromoacetic acid, Chlorite, Di(2-ethylhexyl) phthalate, Cadmium (total), Chloromethane, n-Nitrosodimethylamine, Chlorate, Bromate, Vinyl chloride, Dibromomethane, Bromochloromethane, Chloroethane

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

Nitrate, Barium (total), Arsenic (total), Manganese, Alpha particle activity, Combined Uranium (pCi/L), Chromium (total), Selenium (total), Nitrite, Radon, Bromide, Mercury (total inorganic), Chloromethane, Phosphorus, Lithium, Tin (total)

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

Bromide, Chlorate, Strontium, Lithium, Molybdenum, Tin (total), Phosphorus, Aldicarb sulfoxide, Metolachlor, Ethyl ether, DCPA di acid degradate, Chloromethane, Dichlorodifluoromethane, Bromomethane, Chloroethane, Trichlorofluoromethane, trans-1,3-Dichloropropene, Acetone, Methyl ethyl ketone, Naphthalene, Methyl isobutyl ketone, MTBE, Tetrahydrofuran, n-Nitrosodimethylamine, Dibromomethane, 1,2,4-Trimethylbenzene, 1,3,5-Trimethylbenzene, Bromochloromethane, Bromochloroacetic acid, 1,1-Dichloroethane, Isopropylbenzene, n-Propylbenzene, Radon, Dichlorofluoromethane, Perfluorobutane Sulfonate (PFBS), Perfluorobutanoic Acid (PFBA), Perfluorohexane Sulfonate (PFHXS), Perfluorohexanoic Acid (PFXHA), Perfluorooctane Sulfonate (PFOS), Perfluorooctanoic Acid (PFOA), Perfluoropentanoic Acid (PFPEA)

  Testing Summary for Minnesota

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

Contaminants reported as tested by water suppliers in Minnesota 189
  Contaminants tested due to federal law: 74
  Contaminants tested in addition to those required by federal law: 115
  Violation Summary for Minnesota

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

Violation Type Number of Violations
Failure to monitor, Routine Major (Coliform bacteria) 168
Over maximum contaminant level, Average 81
Maximum contaminant level, Monthly (Coliform bacteria) 70
Monitoring and Reporting Disinfection Byproduct Rule 67
Failure to report information to the public or state agency in the Consumer Confidence Report 37
Follow-up and Routine Tap Sampling 34
Failure to monitor, Routine Minor (Coliform bacteria) 23
Failure to monitor regularly 11
Maximum contaminant level, Acute (Coliform bacteria) 6
Filter Turbidity Reporting 5
Initial Tap Sampling for Lead and Copper 2
Water Quality Program Entry Point Non-Compliance 1
Treatment Technique (Surface Water Treatment Rule) 1
Excess Turbidity at 0.3 NTU 1

Sources : EWG (Environmental Working Group)