What are eutrophic lakes in Wisconsin?

267 eutrophic lakes in Wisconsin. High nutrients, frequent algae, reduced clarity.

What does eutrophic mean?

High nutrients, frequent algae, reduced clarity.

Eutrophic Lakes in Wisconsin

A eutrophic lake is a productive ecosystem with the trade-offs that come with productivity: more food at the base of the food web, more clarity reduction by mid-summer, more dissolved-oxygen variability near the bottom. 267 Wisconsin lakes register as eutrophic. Only 6% are deep — eutrophy correlates with shallowness, agricultural watersheds, and the kind of nutrient-input history that takes decades to shift.

Eutrophic lakes typically grade C or D on our A–F scale. The same nutrient richness that defines the trophic class drives the lower grade.

#	Lake	County	Grade	Clarity	Depth	TSI
1	Gaslyn Lake	Burnett	A	4.5 ft	12 ft	51
2	Potter Lake	Walworth	B	4.3 ft	26 ft	54
3	Lake St Croix	St. Croix	B	5.6 ft	60 ft	53
4	Boulder Lake	Vilas	B	5.6 ft	23 ft	50
5	Pickerel Lake	Vilas	B	6 ft	26 ft	50
6	Round Lake	Oneida	B	4.4 ft	15 ft	52
7	Rice Lake	Iron	B	5 ft	21 ft	52
8	Long Lake	Shawano	B	6 ft	35 ft	50
9	Nelson Lake	Sawyer	B	5 ft	-	52
10	Rush Lake	Vilas	B	5 ft	7 ft	51
11	Rush Lake	Winnebago	B	3.2 ft	5 ft	56
12	North Lake	Barron	B	5.5 ft	21 ft	51
13	Crescent Lake	Polk	B	4.5 ft	43 ft	50
14	Red Cedar Lake	Jefferson	B	4 ft	6 ft	53
15	Wolf Lake	Fond du Lac	B	5 ft	47 ft	54
16	Bark Lake	Washington	B	5.5 ft	34 ft	54
17	Mud Lake	Polk	B	4.3 ft	15 ft	53
18	Loon Lake	Shawano	B	5.5 ft	22 ft	50
19	Big Arbor Vitae Lake	Vilas	B	6 ft	41 ft	51
20	Bearskin Lake	Oneida	B	6 ft	26 ft	51
21	White Lake	Waupaca	B	5.6 ft	10 ft	50
22	Hartlaub Lake	Manitowoc	B	5 ft	60 ft	55
23	Lake Esadore	Taylor	B	4.5 ft	36 ft	52
24	Amnicon Lake	Douglas	B	5 ft	31 ft	52
25	Eagle Spring Lake	Waukesha	B	4.5 ft	8 ft	51
26	Ward Lake	Polk	B	6 ft	43 ft	50
27	Druid Lake	Washington	B	5.5 ft	53 ft	51
28	Whitewater Lake	Walworth	B	4 ft	35 ft	54
29	Big Dardis Lake	Price	B	5.5 ft	-	50
30	Lake Waubesa	Dane	B	3.2 ft	38 ft	58
31	School Section Lake	Waukesha	B	6.2 ft	8 ft	51
32	School Section Lake	Waupaca	B	6.5 ft	38 ft	50
33	Friess Lake	Washington	B	4 ft	48 ft	56
34	Wood Lake	Burnett	B	5.5 ft	35 ft	51
35	Horseshoe Lake	Manitowoc	B	6.5 ft	54 ft	53
36	Deep Hole Lake	Oneida	B	4.3 ft	-	52
37	East Twin Lake	Marquette	B	3.3 ft	8 ft	53
38	Random Lake	Sheboygan	B	4.5 ft	22.2 ft	52
39	Big Stone Lake	Oneida	B	4.2 ft	57 ft	53
40	Blue Spring Lake	Jefferson	B	6.2 ft	27 ft	51
41	Lake Sherwood	Adams	B	5.5 ft	27 ft	51
42	George Lake	Oneida	B	5 ft	26 ft	51
43	Spur Lake	Oneida	B	2 ft	3 ft	58
44	Hiawatha Lake	Vilas	B	4 ft	58 ft	52
45	Lake Thompson	Oneida	B	4 ft	30 ft	53
46	Shoe Lake	Manitowoc	B	7 ft	34 ft	50
47	Clarey Lake	Polk	B	4.3 ft	49 ft	51
48	Van Zile Lake	Forest	B	5.4 ft	17 ft	50
49	Black Hawk Lake	Iowa	B	5 ft	42 ft	51
50	Granite Lake at	Barron	B	6 ft	34 ft	51
51	Tichigan Lake	Racine	B	5.5 ft	63 ft	52
52	Quarry Lake	Brown	B	8 ft	-	52
53	Unnamed Lake	Polk	B	5 ft	-	51
54	Red Bass Lake	Vilas	B	3.4 ft	22 ft	54
55	Lake Wingra	Dane	B	4 ft	14 ft	56
56	Bakkens Pond	Sauk	B	2.5 ft	-	57
57	Arkdale Lake	Adams	B	5 ft	10.5 ft	51
58	Patrick Lake	Adams	B	5 ft	21 ft	51
59	Oneida Lake	Oneida	B	5.5 ft	34 ft	51
60	Dunes Lake	Door	B	4 ft	1 ft	53
61	Kaine Lake	Forest	B	3.2 ft	-	55
62	Wind Lake	Racine	C	8.7 ft	47 ft	58
63	Delavan Lake	Walworth	C	8.9 ft	52 ft	53
64	Green Lake	Sawyer	C	4.7 ft	9 ft	53
65	Fuller Lake	Oneida	C	4.3 ft	-	53
66	Pickerel Lake	Oconto	C	4.5 ft	-	54
67	Cranberry Lake	Oneida	C	4.5 ft	23 ft	55
68	Round Lake	Price	C	4 ft	24 ft	55
69	Clear Lake	Rock	C	2.8 ft	12 ft	60
70	Rice Lake	Barron	C	4.1 ft	19 ft	55
71	Rice Lake	Vilas	C	3.5 ft	7 ft	58
72	Rice Lake	Polk	C	4.5 ft	10 ft	53
73	Townline Lake	Oneida	C	6.4 ft	19 ft	52
74	Lawrence Lake	Marquette	C	6.7 ft	14 ft	50
75	Long Lake	Polk	C	5.9 ft	17 ft	51
76	Long Lake	Polk	C	5 ft	44 ft	53
77	Long Lake	Sauk	C	4.1 ft	-	54
78	Birch Lake	Washburn	C	5.5 ft	73 ft	52
79	Kathan Lake	Oneida	C	2.7 ft	15 ft	58
80	Dog Lake	Oneida	C	3.9 ft	22 ft	54
81	Lake Alice	Lincoln	C	4.3 ft	-	56
82	Rock Lake	Vilas	C	6.2 ft	18 ft	51
83	Pike Lake	Marathon	C	5 ft	34 ft	53
84	Pike Lake	Price	C	3 ft	17 ft	58
85	Turner Lake	Price	C	3 ft	12 ft	58
86	Big Round Lake	Polk	C	5 ft	17 ft	52
87	Lac Vieux Desert Lake	Vilas	C	5.7 ft	38 ft	52
88	Lake Nokomis	Oneida	C	4.3 ft	33 ft	56
89	Cochran Lake	Vilas	C	6 ft	12 ft	52
90	Butternut Lake	Price	C	4 ft	32 ft	56
91	First Black Lake	Iron	C	2.5 ft	19 ft	58
92	Moen Lake	Oneida	C	2.8 ft	11 ft	58
93	Mann Lake	Vilas	C	6.8 ft	18 ft	52
94	Lake Emily	Dodge	C	3.5 ft	10 ft	58
95	Deer Lake	Oneida	C	4 ft	20 ft	54
96	Minong Flowage Lake	Washburn	C	3.5 ft	21 ft	58
97	Duck Lake	Langlade	C	3.7 ft	19 ft	55
98	Mcdill Pond	Portage	C	5 ft	19 ft	55
99	Jordan Pond	Portage	C	4 ft	7 ft	56
100	Loon Lake	Chippewa	C	4.9 ft	9 ft	54

All eutrophic lakes →Minnesota version →Illinois version →Michigan version →Iowa version →Ohio version →Pennsylvania version →New York version →Missouri version →Indiana version →North Dakota version →South Dakota version →Florida version →Colorado version →North Carolina version →Vermont version →Texas version →Oregon version →Arkansas version →Oklahoma version →Kansas version →Nebraska version →Nevada version →Arizona version →Idaho version →Montana version →New Mexico version →Tennessee version →Alabama version →Virginia version →Kentucky version →Utah version →Washington version →Wyoming version →Georgia version →Massachusetts version →Ontario version →Québec version →Nova Scotia version →British Columbia version →Newfoundland and Labrador version →All Wisconsin lakes →

Source: EPA National Aquatic Resource Surveys, 2026.