countyscore

Best Water Quality Counties in Wisconsin

EPA drinking water health violations and safety grades Compare rankings across all 72 counties.

Average Water Quality Score
40/100
Top County
Door County
Counties Ranked
71

Top 10

#1
Door County
WI
86/100
#2
Milwaukee County
WI
72/100
#3
Wood County
WI
68/100
#4
Portage County
WI
67/100
#5
Outagamie County
WI
66/100
#6
Dane County
WI
65/100
#7
Racine County
WI
63/100
#8
Washington County
WI
63/100
#9
Brown County
WI
62/100
#10
La Crosse County
WI
62/100

All Wisconsin Counties Ranked

#CountyWater Quality ScoreOverall Score
1Door County, WI
86
61.5
2Milwaukee County, WI
71.5
24.7
3Wood County, WI
67.5
53.1
4Portage County, WI
67.3
52
5Outagamie County, WI
66.2
48.1
6Dane County, WI
65
38
7Racine County, WI
63.2
38.7
8Washington County, WI
63.2
52.5
9Brown County, WI
62.3
44.1
10La Crosse County, WI
61.5
42.2
11Sheboygan County, WI
61.2
49.4
12Fond du Lac County, WI
60.4
47.8
13Waupaca County, WI
58.1
54.7
14Rock County, WI
57.1
38.9
15Chippewa County, WI
56
42.5
16St. Croix County, WI
53.8
50.8
17Eau Claire County, WI
53.6
50.8
18Manitowoc County, WI
51.8
52.7
19Marathon County, WI
50.7
49.5
20Kenosha County, WI
49
39.9
21Dunn County, WI
48.2
49.2
22Pierce County, WI
48.2
53.4
23Winnebago County, WI
47.9
45.9
24Green Lake County, WI
46.4
51.8
25Lincoln County, WI
46
45.6
26Kewaunee County, WI
45.9
58.6
27Calumet County, WI
45.5
39.2
28Ozaukee County, WI
45.2
56.1
29Barron County, WI
45.1
51.1
30Sauk County, WI
44.4
42.5
31Shawano County, WI
44.3
53.2
32Polk County, WI
44
51.7
33Walworth County, WI
42.7
50.4
34Burnett County, WI
41.8
47.6
35Waushara County, WI
40.3
54.5
36Juneau County, WI
39.7
46.2
37Green County, WI
39.1
54
38Monroe County, WI
37.3
41.9
39Buffalo County, WI
36.7
60.4
40Oneida County, WI
36.6
60.2
41Bayfield County, WI
34.3
58.6
42Marinette County, WI
33.3
49.9
43Douglas County, WI
33.2
40
44Price County, WI
32.8
59.4
45Richland County, WI
32.2
53
46Dodge County, WI
31.9
44.5
47Oconto County, WI
31.7
56.1
48Washburn County, WI
31.1
58.2
49Jackson County, WI
30.3
49.6
50Trempealeau County, WI
29.1
56
51Jefferson County, WI
28.7
48.6
52Grant County, WI
27.9
49.2
53Langlade County, WI
24.3
54.7
54Lafayette County, WI
23.2
54
55Columbia County, WI
22.3
47.6
56Clark County, WI
22
51.4
57Vernon County, WI
22
51.6
58Crawford County, WI
21.1
46.1
59Taylor County, WI
20.6
51.7
60Vilas County, WI
20.6
65.2
61Forest County, WI
20.5
53.5
62Marquette County, WI
20
51.7
63Waukesha County, WI
19.5
51.9
64Iron County, WI
19.1
65.4
65Sawyer County, WI
17.9
48.6
66Iowa County, WI
17.1
56.2
67Pepin County, WI
12.4
56.5
68Rusk County, WI
12
53.8
69Florence County, WI
10.6
56.6
70Ashland County, WI
9.5
37.6
71Adams County, WI
3.7
42.8

Data Source

Water Quality data from WaterByCounty. See full details at WaterByCounty. Data updated February 2026.