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STATE

Wisconsin

CONTAMINANTS

130

serves

4,045,000

data

2013-2024

UTILITIES

1,030

Overview

EWG's drinking water quality report for Wisconsin shows results of tests conducted by the water utilities in Wisconsin and provided to EWG by the Wisconsin Department of Natural Resources.

LARGE UTILITIES
ALL UTILITIES WITH VIOLATIONS
LARGE UTILITIES WITH VIOLATIONS

Large utilities in Wisconsin

Below are utilities in Wisconsin serving over 10,000 people, listed alphabetically.

UtilityLocationPeople Served
Allouez WaterworksGreen Bay, WI13,932
Appleton WaterworksMenasha, WI72,000
Ashwaubenon WaterworksGreen Bay, WI17,730
Baraboo WaterworksBaraboo, WI12,048
Beaver Dam Water UtilityBeaver Dam, WI16,200
Bellevue WaterworksGreen Bay, WI15,365
Brookfield Water UtilityBrookfield, WI29,070
Brown Deer WaterworksBrown Deer, WI12,741
Cedarburg L & W CommissionCedarburg, WI11,900
Chippewa Falls WaterworksChippewa Falls, WI13,375
City of BeloitBeloit, WI37,110
Cudahy WaterworksCudahy, WI18,659
Darboy Sanitary District 1Appleton, WI12,000
De Pere Water DepartmentDe Pere, WI23,920
Eau Claire WaterworksEau Claire, WI66,060
Fitchburg Utility District 1Fitchburg, WI15,000
Fond Du Lac WaterworksFond Du Lac, WI42,000
Fort Atkinson WaterworksFort Atkinson, WI12,125
Franklin Water UtilityFranklin, WI22,500
Germantown Water UtilityGermantown, WI20,027
Glendale WaterworksGlendale, WI12,883
Grafton WaterworksGrafton, WI11,745
Grand Chute Tn San District 1Grand Chute, WI21,583
Green Bay WaterworksGreen Bay, WI104,057
Greendale WaterworksGreendale, WI14,046
Hartford WaterworksHartford, WI15,384
Howard WaterworksGreen Bay, WI18,900
Hudson WaterworksHudson, WI17,100
Janesville Water UtilityJanesville, WI62,720
Kaukauna UtilitiesKaukauna, WI13,430
Kenosha Water UtilityKenosha, WI99,218
La Crosse WaterworksLa Crosse, WI53,000
Little Chute WaterworksLittle Chute, WI11,040
Madison Water UtilityMadison, WI235,000
Manitowoc WaterworksManitowoc, WI34,500
Marinette WaterworksMarinette, WI10,968
Marshfield UtilitiesMarshfield, WI18,708
Menasha Elec & Water UtilMenasha, WI14,728
Menomonee Falls WW - Surface WaterMenomonee Falls, WI23,867
Menomonie WaterworksMenomonie, WI15,950
Mequon Water UtilityMequon, WI11,152
Middleton WaterworksMiddleton, WI17,903
Milwaukee WaterworksMilwaukee, WI647,290
Monroe WaterworksMonroe, WI10,780
Neenah WaterworksNeenah, WI25,892
New Berlin Water UtilityNew Berlin, WI27,899
Oak Creek WaterworksOak Creek, WI32,104
Oconomowoc WaterworksOconomowoc, WI15,805
Onalaska WaterworksOnalaska, WI18,000
Oshkosh WaterworksOshkosh, WI63,000
Platteville WaterworksPlatteville, WI12,268
Pleasant Prairie Water UtilityPleasant Prairie, WI10,754
Plover WaterworksPlover, WI12,420
Port Washington WaterworksPort Washington, WI11,762
Portage WaterworksPortage, WI10,300
Racine WaterworksRacine, WI105,100
River Falls WaterworksRiver Falls, WI15,229
Sheboygan Water UtilitiesSheboygan, WI49,288
Shorewood WaterworksShorewood, WI13,189
South Milwaukee WaterworksSouth Milwaukee, WI21,340
Stevens Point WaterworksStevens Point, WI24,551
Stoughton WaterworksStoughton, WI12,698
Sun Prairie UtilitiesSun Prairie, WI32,613
Superior Water Light & Power CompanySuperior, WI29,571
Sussex Village Hall & Water UtilitySussex, WI10,573
Two Rivers WaterworksTwo Rivers, WI11,232
Verona WaterworksVerona, WI10,619
Village of Caledonia Water UtilityCaledonia, WI21,819
Watertown WaterworksWatertown, WI23,127
Waukesha Water UtilityWaukesha, WI70,718
Waunakee WaterworksWaunakee, WI13,322
Waupun UtilitiesWaupun, WI11,340
Wausau WaterworksWausau, WI39,106
Wauwatosa WaterworksWauwatosa, WI49,064
West Allis WaterworksWest Allis, WI63,240
West Bend WaterworksWest Bend, WI31,500
Weston Municipal UtilitiesWeston, WI15,045
Whitefish Bay WaterworksWhitefish Bay, WI14,272
Whitewater WaterworksWhitewater, WI14,000
Wisconsin Rapids Water Works & Lighting Comm.Wisconsin Rapids, WI20,000

Utilities that accumulated/accrued the most violation points as of July 2021 to June 2024 in Wisconsin

The Environmental Protection Agency's Enforcement and Compliance History Online (ECHO) database collects compliance and enforcement-related information for drinking water utilities nationwide. ECHO water quality violation scores take into account federal health-based water quality standards, as well as monitoring, reporting and other drinking water quality requirements. Points are accrued based on specific problems at the utility - violations of health-based drinking water standards receive more points than monitoring and reporting violations - and the length of time until the violations were corrected.

UtilityLocationPeople ServedViolation Points
Pewaukee Village WaterworksPewaukee, WI8,16666
Jefferson WaterworksJefferson, WI7,92641
La Valle WaterworksLa Valle, WI36531
Waupun Correctional InstWaupun, WI4,90131
Ashland Water UtilityAshland, WI9,11523
River Springs Apartments LlcRochester, WI3817
Manitou Falls Sanitary District No 1Superior, WI9517
Pewaukee City Water and Sewer UtilityPewaukee, WI8,67116
Winneconne WaterworksWinneconne, WI2,37716
Whispering Pines AptsSalem, WI3012
Deer Trail VillageMosinee, WI12011
Prairie Apts 1 & 2Salem, WI15011
Prescott WaterworksPrescott, WI4,25810
Fairchild WaterworksFairchild, WI56410
Embarrass WaterworksEmbarrass, WI4049
Oconomowoc WaterworksOconomowoc, WI15,8059
Bloomfield, Village OfPell Lake, WI4,0718
Sharon WaterworksSharon, WI1,5498
Glen Flora WaterworksGlen Flora, WI938
Leroy Sanitary District 1Leroy, WI3207
Randolph Water DepartmentRandolph, WI1,8007
Sheldon Water UtilitySheldon, WI2657
Country View Mobile Home Community LlcOregon, WI806
Dodge Sanitary District 1Dodge, WI2666
Carriage Hills CondominiumsElm Grove, WI506
Lakeview Specialty HospitalWaterford, WI3846
Wind Point Water DepartmentRacine, WI1,8046
Hazel Green WaterworksHazel Green, WI1,2566
Colonial Gardens HomesFond Du Lac, WI486
Country Cove Court LlcHudson, WI1506

Large utilities that accumulated/accrued the most violation points as of July 2021 to June 2024 in Wisconsin

The Environmental Protection Agency's Enforcement and Compliance History Online (ECHO) database collects compliance and enforcement-related information for drinking water utilities nationwide. ECHO water quality violation scores take into account federal health-based water quality standards, as well as monitoring, reporting and other drinking water quality requirements. Points are accrued based on specific problems at the utility - violations of health-based drinking water standards receive more points than monitoring and reporting violations - and the length of time until the violations were corrected.

UtilityLocationPeople ServedViolation Points
Oconomowoc WaterworksOconomowoc, WI15,8059
South Milwaukee WaterworksSouth Milwaukee, WI21,3402
Waukesha Water UtilityWaukesha, WI70,7182
Sussex Village Hall & Water UtilitySussex, WI10,5731
Marinette WaterworksMarinette, WI10,9681
Whitewater WaterworksWhitewater, WI14,0001
Greendale WaterworksGreendale, WI14,0461
Howard WaterworksGreen Bay, WI18,9001
Grand Chute Tn San District 1Grand Chute, WI21,5831
Sheboygan Water UtilitiesSheboygan, WI49,2881

Contaminants found in Wisconsin above health guidelines

Found above health guidelines Found
Contaminant # of Utilities People Served # of Utilities People Served
Total trihalomethanes (TTHMs)5513,859,1725663,879,871
Bromodichloromethane5393,838,8525553,863,347
Haloacetic acids (HAA5)5443,810,8885503,818,225
Dichloroacetic acid4433,537,8005193,780,327
Dibromoacetic acid4513,526,8264733,649,304
Chloroform4663,483,1665713,880,646
Dibromochloromethane4803,425,9825243,835,661
Trichloroacetic acid3723,076,5934453,615,039
Nitrate & nitrite4623,016,4676653,653,840
Haloacetic acids (HAA9)1082,977,5441103,001,022
Total PFOS and PFOA2682,936,9082873,053,828
Chromium (hexavalent)902,736,740992,861,254
Perfluorooctanoic acid (PFOA)2152,598,8742412,926,274
Nitrate4532,514,1606953,227,536
Radium, combined (-226 & -228)6922,187,4777172,260,660
Perfluorohexane sulfonate (PFHXS)2632,091,5262632,091,526
Perfluorooctane sulfonate (PFOS)1201,626,8232432,983,002
Bromate171,116,065171,116,065
Arsenic3281,096,7383281,096,738
Tetrachloroethylene (perchloroethylene)20426,47622500,069
Perfluorononanoic acid (PFNA)27424,10527424,105
Bromoform69333,9943833,248,837
Radon40319,87540319,875
Perfluoroheptane sulfonic acid (PFHpS)11283,55711283,557
Uranium, combined (pCi/L)72201,1495812,416,722
Thallium1676,00851139,275
Manganese3040,9355273,200,117
N-ethyl perfluorooctane sulfonamido acetic acid (N-EtFOSAA)139,106242,296
Trichloroethylene326,11119463,695
6:2 Fluorotelomer Sulfonic Acid (6:2 FTSA)223,71611293,858
Perfluorodecanoic acid (PFDA)219,570219,570
Perfluoropentane sulfonic acid (PFPeS)415,76415309,464
Vinyl chloride111,900649,778
Styrene14,96047103,471
Bromochloromethane34,810533,855
Cadmium74,6132063,726
Barium14,0717843,894,045
1,1,1,2-Tetrachloroethane11,06911,069
1,2-Dichloroethane21,055523,448
Antimony125411,079,956

Contaminants found in Wisconsin above legal limits

Contaminant # of Utilities People Served

Arsenic		29,295

Nitrate		140

What filter type is right for you?

Water
Contaminants

view utility

Carbon Filters

Can reduce the levels of many common contaminants.

pros

  • Lower upfront cost
  • Reduced maintenance

cons

  • Does not remove all contaminants

Reverse Osmosis

Most effective at reducing contaminants.

pros

  • Most effective

cons

  • Higher upfront cost
  • Requires more maintenance
  • Wastes water

Other Considerations

Ion Exchange

Pros: Softens hard water, Reduces some contaminants

Cons: Doesn't remove all contaminants

Whole-House Filters

Pros: Useful for reducing radiologicals and TCE

Cons: Expensive to install and maintain, Risk of bacterial contamination

Distillation

Pros: Removes heavy metals and harmful microbes

Cons: Does not reduce most contaminants

view utility UNDERSTAND FILTER TECHNOLOGY

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