The Power of Information

National Drinking Water Database


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
Bromodichloromethane3,517,0563,517,056560560
Dibromochloromethane3,493,0423,329,041534458
Lead (total)3,227,0153,227,0151,6541,654
Total haloacetic acids (HAAs)3,442,3823,059,332478421
Bromoform2,835,9242,835,924364364
Dichloroacetic acid2,638,9392,638,939322322
Total trihalomethanes (TTHMs)3,605,1532,196,553609212
Arsenic (total)1,753,4651,753,465773773
Copper3,247,0511,439,3571,720489
Chloroform3,527,3841,241,978584161

Water Utilities in Wisconsin Reporting Chemicals Exceeding Health Guidelines

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

System
Population
Chemicals tested
Chemicals found
Chemicals exceeding
health guidelines
Grafton Waterworks13,3101303822
Mattoon Waterworks4501392821
Darien Waterworks1,5991283119
New Lisbon Waterworks2,4661303018
Greenville Sanitary Dist5,2111352518
Fond DU Lac Waterworks42,0001152818
Muskego Water Utility8,1501433118
Waukesha Water Utility65,0001333518
Antigo Waterworks8,6781322717
Elkhorn Waterworks8,8201342317
Franklin Water Utility22,500392817
City of Hayward Water Utility2,3131172916
Manitou Falls Sanitary District No. 1951412416
Scott Water Utility Dist1,500582616
Brookfield Water Utility21,9001093216
City of Pewaukee Water & Sewer Utility - Main6,1181412716
Hartford Waterworks11,4191312516
Lomira Waterworks2,461802516
Fox Lake Correctional Institution1,2501182916
Cambria Waterworks7781423016

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.

110Total Contaminants Detected (2004 - 2008)
30Agricultural 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

33Sprawl 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

75Industrial 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)

22Water 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

26Naturally 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)

30Unregulated 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 Wisconsin163
 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 TypeNumber of Violations
Failure to monitor regularly12
Failure to report information to the public or state agency in the Consumer Confidence Report4
Public Notification Violation for National Primary Drinking Water Regulations3
Maximum contaminant level, Monthly (Coliform bacteria)1
Failure to monitor, Routine Minor (Coliform bacteria)1
Failure to monitor, Routine Major (Coliform bacteria)1