926 systems serving 6,710,306 people
  This drinking water quality report shows results of tests conducted by water utilities in Michigan, provided to the Environmental Working Group (EWG) by the Michigan Department of Environmental Quality. 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.

  25 Contaminants Exceeding Health Based Limits

Contaminants detected in Michigan 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 trihalomethanes (TTHMs) 5,742,051 5,319,041 488 273
Total haloacetic acids (HAAs) 5,090,500 5,021,919 298 293
Bromodichloromethane 4,775,322 4,775,322 426 426
Dibromochloromethane 4,709,136 4,688,684 400 385
Dichloroacetic acid 4,048,522 4,048,522 241 241
Chloroform 4,804,745 3,998,801 466 230
Bromoform 1,406,539 1,406,539 156 156
Lead (total) 710,990 710,990 224 224
Arsenic (total) 524,299 524,299 200 200
Trichloroacetic acid 4,038,187 269,646 229 27

  Sources of Michigan Drinking Water Contaminants

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

54 Total Contaminants Detected (2007 - 2008)
12 Agricultural Pollutants
(pesticides, fertilizer, factory farms)

Arsenic (total), Nitrate, Nitrite, Selenium (total), Dalapon, Picloram, Atrazine, Dacthal, Bromomethane, p-Dichlorobenzene, 1,2-Dichloropropane, Ethylbenzene

17 Sprawl 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), Dichloromethane (methylene chloride), o-Xylene, Benzene, Dacthal, p-Dichlorobenzene, Methyl ethyl ketone

37 Industrial Pollutants

Arsenic (total), Barium (total), Cadmium (total), Chromium (total), Lead (total), Manganese, Nitrate, Nitrite, Selenium (total), Antimony (total), Thallium (total), 1,4-Dioxane, Chloromethane, Methyl ethyl ketone, Methyl isobutyl ketone, MTBE, cis-1,2-Dichloroethylene, Dibromomethane, 2,2-Dichloropropane, Bromochloromethane, Xylenes (total), Dichloromethane (methylene chloride), p-Dichlorobenzene, Vinyl chloride, 1,1-Dichloroethylene, trans-1,2-Dichloroethylene, 1,2-Dichloroethane, 1,1,1-Trichloroethane, 1,2-Dichloropropane, Trichloroethylene, Tetrachloroethylene, Benzene, Toluene, Ethylbenzene, Isopropylbenzene, Styrene, o-Xylene

16 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, Cadmium (total), Chloromethane, Vinyl chloride, Dibromomethane, Bromochloromethane

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

Nitrate, Copper, Barium (total), Lead (total), Arsenic (total), Manganese, Chromium (total), Selenium (total), Nitrite, Chloromethane

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

Lead (total), 1,4-Dioxane, Dacthal, Chloromethane, Bromomethane, Methyl ethyl ketone, Methyl isobutyl ketone, MTBE, Dibromomethane, 2,2-Dichloropropane, Bromochloromethane, Bromochloroacetic acid, Isopropylbenzene

  Testing Summary for Michigan

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

Contaminants reported as tested by water suppliers in Michigan 165
  Contaminants tested due to federal law: 75
  Contaminants tested in addition to those required by federal law: 90
  Violation Summary for Michigan

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

Violation Type Number of Violations
Failure to monitor regularly 869
Failure to monitor, Routine Major (Coliform bacteria) 362
Maximum contaminant level, Monthly (Coliform bacteria) 346
Over maximum contaminant level, Average 156
Failure to report information to the public or state agency in the Consumer Confidence Report 110
Monitoring and Reporting Disinfection Byproduct Rule 88
Failure to monitor, Routine Minor (Coliform bacteria) 57
Failure to monitor, Repeat Minor (Coliform bacteria) 44
Follow-up and Routine Tap Sampling 40
Public Notification Violation for National Primary Drinking Water Regulations 39
Operations Report 34
Variance/Exemption/Other Compliance 24
Record Keeping Violation 18
Maximum contaminant level, Acute (Coliform bacteria) 15
Failure to monitor, Repeat Major (Coliform bacteria) 13
Initial Tap Sampling for Lead and Copper 7
Initial Water Quality Parameter Monitoring and Reporting 5
Public Education 4
Treatment Technique Precursor Removal 4
Filter Turbidity Reporting 3
Excess Turbidity at 1 NTU 3
Treatment Technique (Surface Water Treatment Rule) 3
Non-Acute maximum residual disinfectant level 3
Treatment Technique No Certif. Operator 2
Inadequate reporting of information to the public 2
Failure to notify state agency 2
Improper Treatment Techniques 1
Initial, Follow-up, or Routine Source Water Treatment Monitoring and Reporting 1

Sources : EWG (Environmental Working Group)