All water systems in Wisconsin
11,026 systems
| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
Hartford Waterworks Hartford · Washington County |
15,805 | 0 | 0 | |
|
Oconomowoc Waterworks Oconomowoc · Waukesha County |
15,805 | 1 | 1 | |
|
Menasha Elec & Water Util Menasha · Winnebago County |
15,144 | 1 | 1 | |
|
Waunakee Waterworks Waunakee · Dane County |
14,879 | 1 | 0 | |
|
Greendale Waterworks Greendale · Milwaukee County |
14,393 | 1 | 0 | |
|
Whitefish Bay Waterworks Whitefish Bay · Milwaukee County |
14,272 | 0 | 0 | |
|
Verona Waterworks Verona · Dane County |
14,030 | 3 | 1 | |
|
Fox Crossing Utilities West Neenah · Winnebago County |
14,000 | 2 | 0 | |
|
Whitewater Waterworks Whitewater · Walworth County |
14,000 | 2 | 0 | |
|
Allouez Waterworks Green Bay · Brown County |
13,923 | 2 | 0 | |
|
Shorewood Waterworks Shorewood · Milwaukee County |
13,535 | 0 | 0 | |
|
Plover Waterworks Plover · Portage County |
13,486 | 0 | 0 | |
|
Chippewa Falls Waterworks Chippewa Falls · Chippewa County |
13,375 | 0 | 0 | |
|
Stoughton Waterworks Stoughton · Dane County |
13,078 | 0 | 0 | |
|
Darboy Sanitary Dist 1 Appleton · Outagamie County |
13,024 | 1 | 0 | |
|
Glendale Waterworks Glendale · Milwaukee County |
12,883 | 3 | 2 | |
|
Port Washington Waterworks Port Washington · Ozaukee County |
12,853 | 1 | 0 | |
|
Brown Deer Waterworks Brown Deer · Milwaukee County |
12,741 | 0 | 0 | |
|
Baraboo Waterworks Baraboo · Sauk County |
12,703 | 0 | 0 | |
|
Cedarburg L & W Commission Cedarburg · Ozaukee County |
12,500 | 0 | 0 | |
|
Fort Atkinson Waterworks Fort Atkinson · Jefferson County |
12,390 | 0 | 0 | |
|
Grafton Waterworks Grafton · Ozaukee County |
12,269 | 0 | 0 | |
|
Platteville Waterworks Platteville · Grant County |
12,268 | 0 | 0 | |
|
Little Chute Waterworks Little Chute · Outagamie County |
12,168 | 2 | 0 | |
|
Sussex Village Hall & Water Utility Sussex · Waukesha County |
11,750 | 2 | 1 | |
|
Greenville Utilities Vil of Greenville · Outagamie County |
11,340 | 0 | 0 | |
|
Two Rivers Waterworks Two Rivers · Manitowoc County |
11,270 | 3 | 1 | |
|
Oregon Waterworks Oregon · Dane County |
11,200 | 0 | 0 | |
|
Mequon Water Utility Mequon · Ozaukee County |
11,152 | 0 | 0 | |
|
Burlington Waterworks Burlington · Racine County |
11,043 | 0 | 0 | |
|
Marinette Waterworks Marinette · Marinette County |
10,968 | 1 | 0 | |
|
Fox Crossing Utilities East Neenah · Winnebago County |
10,927 | 2 | 0 | |
|
New Richmond Waterworks New Richmond · St. Croix County |
10,824 | 0 | 0 | |
|
Monroe Waterworks Monroe · Green County |
10,780 | 0 | 0 | |
|
Pleasant Prairie Water Utility Pleasant Prairie · Kenosha County |
10,754 | 2 | 1 | |
|
Deforest Waterworks Deforest · Dane County |
10,500 | 2 | 1 | |
|
Portage Waterworks Portage · Columbia County |
10,437 | 0 | 0 | |
|
Elkhorn Waterworks Elkhorn · Walworth County |
10,317 | 1 | 1 | |
|
Holmen Waterworks Holmen · La Crosse County |
10,147 | 2 | 1 | |
|
Sparta Waterworks Sparta · Monroe County |
10,025 | 1 | 1 | |
|
Fort McCoy North Post Fort Mccoy · Monroe County |
10,000 | 0 | 0 | |
|
Reedsburg Waterworks Reedsburg · Sauk County |
9,984 | 0 | 0 | |
|
Sturgeon Bay Waterworks Sturgeon Bay · Door County |
9,700 | 0 | 0 | |
|
McFarland Waterworks Mc Farland · Dane County |
9,676 | 0 | 0 | |
|
Merrill Waterworks Merrill · Lincoln County |
9,661 | 1 | 0 | |
|
Altoona Waterworks Altoona · Eau Claire County |
9,627 | 2 | 1 | |
|
Shawano Waterworks Shawano · Shawano County |
9,610 | 0 | 0 | |
|
Cottage Grove Waterworks Cottage Grove · Dane County |
9,345 | 2 | 1 | |
|
Hartland Waterworks Hartland · Waukesha County |
9,212 | 0 | 0 | |
|
Tomah Waterworks Tomah · Monroe County |
9,192 | 1 | 0 |
About this data
Rules violated counts the rules a system was in violation of in the past three years, including monitoring and reporting lapses; one rule can carry several violations. Unresolved is the number of those rules currently in violation at EPA's latest data refresh.
Source: the U.S. EPA's Enforcement and Compliance History Online system (ECHO), which publishes the federal Safe Drinking Water Information System. EPA's terms and values are shown as published. The Wisconsin records are from EPA's data refresh of Oct 7, 2026; EPA refreshes this data quarterly, and states report to EPA with a lag of three to six months, so the newest violations may not appear yet.