WISCONSIN
4,278 systems serving 4,694,237 people
 
 
 
  This drinking water quality report shows results of tests conducted by water utilities in Wisconsin, provided to the Environmental Working Group (EWG) by the Wisconsin Department of Natural Resources. 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.

 
Chemicals
Water Utilities
Population Served
Detected Chemicals
110
4,278
4,461,879
Exceed health guidelines*
56
1,928
4,118,242
Exceed Legal Limits*
30
494
1,871,594
Unregulated chemicals detected
29
289
2,207,259
* 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.

 
 
 
  56 Contaminants Exceeding Health Based Limits

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

Contaminant
Population
Number of Systems
At Any Level Above Health Limits At Any Level Above Health Limits
Bromodichloromethane 3,517,056 3,517,056 560 560
Dibromochloromethane 3,493,042 3,329,041 534 458
Lead (total) 3,227,015 3,227,015 1,654 1,654
Total haloacetic acids (HAAs) 3,442,382 3,059,332 478 421
Bromoform 2,835,924 2,835,924 364 364
Dichloroacetic acid 2,638,939 2,638,939 322 322
Total trihalomethanes (TTHMs) 3,605,153 2,196,553 609 212
Arsenic (total) 1,753,465 1,753,465 773 773
Copper 3,247,051 1,439,357 1,720 489
Chloroform 3,527,384 1,241,978 584 161

 
 
 
  Sources of Wisconsin Drinking Water Contaminants

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

110 Total Contaminants Detected (2004 - 2008)
30 Agricultural Pollutants
(pesticides, fertilizer, factory farms)

Arsenic (total), Cyanide, Nitrate & nitrite, Nitrate, Nitrite, Selenium (total), Endrin, Desethylatrazine, Methoxychlor, Dalapon, Endothall, Oxamyl (Vydate), Simazine, Picloram, Dinoseb, Metolachlor, Carbofuran, Atrazine, Alachlor (Lasso), 2,4-D, 2,4,5-TP (Silvex), Bromomethane, Dicamba, 1,2-Dibromo-3-chloropropane (DBCP), Ethylene dibromide (EDB), o-Dichlorobenzene, p-Dichlorobenzene, 1,2-Dichloropropane, Monochlorobenzene (Chlorobenzene), Ethylbenzene

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

Arsenic (total), Cadmium (total), Copper, Cyanide, Lead (total), Mercury (total inorganic), Nitrate & nitrite, Nitrate, Nitrite, Silver (total), Antimony (total), Dalapon, Di(2-Ethylhexyl) adipate, 2,3,7,8-TCDD (Dioxin), 2,4-D, 2,4,5-TP (Silvex), Trichlorofluoromethane, Naphthalene, MTBE, Diethylphthalate, Di-n-butylphthalate, Benzo[a]pyrene, sec-Butylbenzene, Trichlorotrifluoroethane, Xylenes (total), p-Xylene, Dichloromethane (methylene chloride), p-Dichlorobenzene, Tetrachloroethylene, Benzene, Bromobenzene, o-Xylene, n-Propylbenzene

75 Industrial Pollutants

Aluminum, Bromide, Arsenic (total), Barium (total), Cadmium (total), Chromium (total), Cyanide, Lead (total), Manganese, Mercury (total inorganic), Nitrate & nitrite, Nitrate, Nitrite, Selenium (total), Silver (total), Strontium, Antimony (total), Beryllium (total), Thallium (total), Asbestos, p-Isopropyltoluene, Di(2-Ethylhexyl) adipate, Di(2-ethylhexyl) phthalate, 2,3,7,8-TCDD (Dioxin), Chloromethane, Dichlorodifluoromethane, Chloroethane, Trichlorofluoromethane, Hexachlorobutadiene, Naphthalene, MTBE, Diethylphthalate, Di-n-butylphthalate, Pentachlorophenol, cis-1,2-Dichloroethylene, Dibromomethane, 1,2,4-Trimethylbenzene, 1,3,5-Trimethylbenzene, sec-Butylbenzene, Bromochloromethane, Trichlorotrifluoroethane, Ethylene dibromide (EDB), Xylenes (total), p-Xylene, 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, 1,1,1,2-Tetrachloroethane, Tetrachloroethylene, Monochlorobenzene (Chlorobenzene), Benzene, Toluene, Ethylbenzene, Bromobenzene, Isopropylbenzene, Styrene, o-Xylene, n-Propylbenzene, Alpha particle activity (excl radon and uranium), Alpha particle activity (incl. radon & uranium), Combined Uranium (mg/L), Combined Radium (-226 & -228), Radium-226, Radium-228, Potassium-40 (total), Combined Uranium (pCi/L), Gross beta particle activity (pCi/L)

22 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, Monobromoacetic acid, Di(2-ethylhexyl) phthalate, Cadmium (total), Chloramine, Chloromethane, Bromate, Vinyl chloride, Asbestos, Dibromomethane, Bromochloromethane, Benzo[a]pyrene, Chloroethane

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

Nitrate, Copper, Nitrate & nitrite, Barium (total), Lead (total), Arsenic (total), Manganese, Radium-228, Radium-226, Alpha particle activity (excl radon and uranium), Combined Radium (-226 & -228), 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, Silver (total), Potassium-40 (total)

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

Bromide, Chloramine, Lead (total), Strontium, p-Isopropyltoluene, Metolachlor, Chloromethane, Dichlorodifluoromethane, Bromomethane, Chloroethane, Trichlorofluoromethane, Hexachlorobutadiene, Naphthalene, MTBE, Diethylphthalate, Di-n-butylphthalate, Dibromomethane, 1,2,4-Trimethylbenzene, 1,3,5-Trimethylbenzene, sec-Butylbenzene, Bromochloromethane, Dicamba, Trichlorotrifluoroethane, 1,1-Dichloroethane, 1,1,1,2-Tetrachloroethane, Bromobenzene, Isopropylbenzene, n-Propylbenzene, Radon, Potassium-40 (total)

 
 
 
  Testing Summary for Wisconsin

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

Contaminants reported as tested by water suppliers in Wisconsin 163
  Contaminants tested due to federal law: 90
  Contaminants tested in addition to those required by federal law: 73
 
 
 
  Violation Summary for Wisconsin

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

Violation Type Number of Violations
Failure to monitor regularly 12
Failure to report information to the public or state agency in the Consumer Confidence Report 4
Public Notification Violation for National Primary Drinking Water Regulations 3
Maximum contaminant level, Monthly (Coliform bacteria) 1
Failure to monitor, Routine Minor (Coliform bacteria) 1
Failure to monitor, Routine Major (Coliform bacteria) 1



Sources : EWG (Environmental Working Group)