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AquaCensus

Wisconsin public water systems

11,053 active systems regulated under the Safe Drinking Water Act, serving a reported 5.2M people across 90 counties.

Dataset updated . Source: EPA SDWIS/ECHO, refreshed quarterly.

Active systems

11,053

Population served

5.2M

Community systems

1,053

Groundwater share

99.4%

System types in Wisconsin

1,053

Community water system

890

Non-transient non-community water system

9,110

Transient non-community water system

Largest water systems in Wisconsin

The largest active public water systems in Wisconsin by population served
#Water systemCountyPopulation servedTypeSource
1Milwaukee WaterworksMilwaukee626,000CommunitySurface water
2Madison Water UtilityDane272,000CommunityGroundwater
3Green Bay WaterworksBrown107,369CommunitySurface water
4Racine WaterworksRacine105,100CommunitySurface water
5Kenosha Water UtilityKenosha99,218CommunitySurface water
6Appleton WaterworksOutagamie74,511CommunitySurface water
7Waukesha Water UtilityWaukesha70,718CommunityPurchased surface water
8Eau Claire WaterworksEau Claire70,587CommunityGroundwater
9Janesville Water UtilityRock64,415CommunityGroundwater
10West Allis WaterworksMilwaukee63,240CommunityPurchased surface water
11Oshkosh WaterworksWinnebago63,000CommunitySurface water
12La Crosse WaterworksLa Crosse53,000CommunityGroundwater
13Sheboygan Water UtilitiesSheboygan49,931CommunitySurface water
14Wauwatosa WaterworksMilwaukee49,064CommunityPurchased surface water
15Fond Du Lac WaterworksFond du Lac44,303CommunityGroundwater
16Wausau WaterworksMarathon39,994CommunityGroundwater
17Beloit City ofRock36,677CommunityGroundwater
18North Shore Water CommissionMilwaukee35,598CommunitySurface water
19Manitowoc WaterworksManitowoc34,500CommunitySurface water
20Sun Prairie UtilitiesDane33,966CommunityGroundwater
21Oak Creek WaterworksMilwaukee32,104CommunitySurface water
22West Bend WaterworksWashington31,752CommunityGroundwater
23Brookfield Water UtilityWaukesha29,070CommunityGroundwater
24New Berlin Water UtilityWaukesha27,899CommunityPurchased surface water
25Neenah WaterworksWinnebago27,506CommunitySurface water

By county

Waukesha589 systemsVilas465 systemsDoor452 systemsOneida346 systemsDane301 systemsWashington269 systemsOzaukee252 systemsWalworth252 systemsKenosha227 systemsChippewa219 systemsSheboygan215 systemsFond du Lac211 systemsWaupaca207 systemsOconto203 systemsAdams201 systemsSauk199 systemsWaushara197 systemsRacine195 systemsMarathon195 systemsJefferson193 systemsMarinette191 systemsBurnett190 systemsSawyer190 systemsBarron190 systemsBayfield190 systemsDouglas189 systemsPolk187 systemsDodge180 systemsSt. Croix164 systemsMarquette158 systemsRock155 systemsWinnebago153 systemsBrown150 systemsPortage149 systemsWood148 systemsJuneau144 systemsManitowoc142 systemsColumbia141 systemsWashburn129 systemsLa Crosse122 systemsShawano115 systemsLanglade112 systemsEau Claire111 systemsOutagamie105 systemsJackson103 systemsMonroe98 systemsLincoln97 systemsPierce95 systemsClark94 systemsGrant90 systemsRusk86 systemsMilwaukee85 systemsDunn85 systemsAshland82 systemsIowa77 systemsPrice75 systemsTrempealeau75 systemsKewaunee72 systemsBuffalo70 systemsGreen Lake68 systemsVernon66 systemsTaylor60 systemsIron57 systemsForest57 systemsGreen52 systemsCrawford51 systemsCalumet50 systemsFlorence44 systemsLafayette40 systemsRichland38 systemsPepin22 systemsGogebic5 systemsLake3 systemsChisago3 systems
Otsego2 systems
Kandiyohi1 systems
Olmsted1 systems
Meeker1 systems
Winona1 systems
St. Louis1 systems
Winkler1 systems
Schoolcraft1 systems
Larimer1 systems
Boone1 systems
Menominee1 systems
Ionia1 systems
Sonoma1 systems
Taney1 systems
Delta1 systems
Barry1 systems