Eutrophic Lakes in Wisconsin

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

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. 481 Wisconsin lakes register as eutrophic. Only 7% 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 the LakeGrade rubric. The same nutrient richness that defines the trophic class drives the lower grade.

#	Lake	County	Grade	Clarity	Depth	TSI
1	Boot Lake	Vilas	B	-	19 ft	50
2	Big Twin Lake	Waushara	B	-	13 ft	52
3	Unnamed Lake	Douglas	B	-	6 ft	52
4	Unnamed Lake	Washburn	B	-	-	52
5	L St Germain Lk Site K @ S. Bay Lake	Vilas	B	-	53 ft	52
6	Lk Superior Lake	Douglas	B	-	-	53
7	Little Wood Lake	Burnett	B	-	23 ft	51
8	Delavan Lake	Walworth	B	-	52 ft	51
9	Dunes Lake Just Us of Outlet	Door	B	-	-	50
10	Inlet To Dunes Lake	Door	B	-	1 ft	53
11	East Wetland Inlet To Lake Ree	Bayfield	B	-	-	52
12	Indian School Lake	Sawyer	B	-	6 ft	50
13	Wiley Lake	Bayfield	B	-	-	52
14	Two Bear Lake	Rusk	B	-	35 ft	53
15	Chippewa Flowage Lake	Sawyer	B	6.9 ft	92 ft	50
16	Lawrence Lake	Marquette	B	6.7 ft	14 ft	50
17	Rush Lake	Vilas	B	5 ft	7 ft	51
18	Crescent Lake	Polk	B	4.5 ft	43 ft	50
19	Eagle Spring Lake	Waukesha	B	4.3 ft	8 ft	51
20	Lake of the Falls	Iron	B	5.2 ft	23 ft	50
21	East Twin Lake	Marquette	B	3.3 ft	8 ft	53
22	Hiawatha Lake	Vilas	B	4 ft	58 ft	52
23	Shoe Lake	Manitowoc	B	7 ft	34 ft	50
24	Black Brook Flowage Lake	Polk	B	10.5 ft	23 ft	51
25	Clarey Lake	Polk	B	4.3 ft	49 ft	51
26	Van Zile Lake	Forest	B	5.4 ft	17 ft	50
27	Black Hawk Lake	Iowa	B	5 ft	42 ft	51
28	Patrick Lake	Adams	B	5 ft	21 ft	51
29	Clay Lake	Bayfield	B	3.5 ft	45 ft	52
30	Mckenzie Lake	Polk	B	7 ft	25 ft	50
31	Lake Thirty	Barron	B	4.8 ft	27 ft	51
32	Cruson Slough Lake	Richland	B	7.6 ft	-	50
33	Gaslyn Lake	Burnett	C	4.5 ft	12 ft	51
34	Chippewa Flowage -Pokegema Lake	Sawyer	C	5.8 ft	92 ft	51
35	Quarry Lake	Brown	C	8 ft	-	52
36	Delavan Lake	Walworth	C	10 ft	52 ft	55
37	Pickerel Lake	Vilas	C	6 ft	26 ft	50
38	Pickerel Lake	Oconto	C	4.5 ft	-	54
39	Townline Lake	Oneida	C	6.4 ft	19 ft	52
40	Indian Lake	Oneida	C	-	-	55
41	Milwaukee Harbor Lake	Milwaukee	C	8.2 ft	-	52
42	Boulder Lake	Vilas	C	5.6 ft	23 ft	50
43	Fuller Lake	Oneida	C	4.3 ft	-	53
44	Grignon Lake	Oconto	C	6 ft	-	50
45	Round Lake	Price	C	4 ft	24 ft	54
46	Round Lake	Oneida	C	4.4 ft	15 ft	52
47	Rice Lake	Iron	C	5 ft	21 ft	52
48	Rice Lake	Polk	C	4.5 ft	10 ft	53
49	Long Lake	Polk	C	5.9 ft	17 ft	51
50	Long Lake	Polk	C	5 ft	44 ft	53
51	Long Lake	Shawano	C	6 ft	35 ft	50
52	Long Lake	Sauk	C	4.1 ft	-	54
53	Birch Lake	Washburn	C	5.5 ft	73 ft	52
54	Rock Lake	Vilas	C	6.2 ft	18 ft	51
55	North Lake	Barron	C	5.5 ft	21 ft	51
56	Pike Lake	Marathon	C	5 ft	34 ft	53
57	Delavan Lake	Walworth	C	8 ft	52 ft	54
58	Lac Vieux Desert Lake	Vilas	C	5.7 ft	38 ft	52
59	Dog Lake	Oneida	C	3.9 ft	22 ft	54
60	Green Lake	Sawyer	C	4.7 ft	9 ft	53
61	Green Lake	Green Lake	C	11.5 ft	236 ft	53
62	Nelson Lake	Sawyer	C	5 ft	-	52
63	Red Cedar Lake	Jefferson	C	4.3 ft	6 ft	53
64	Cochran Lake	Vilas	C	6 ft	12 ft	52
65	Deer Lake	Oneida	C	4 ft	20 ft	54
66	Duck Lake	Langlade	C	3.5 ft	19 ft	56
67	Loon Lake	Shawano	C	5.5 ft	22 ft	50
68	Bearskin Lake	Oneida	C	6 ft	26 ft	51
69	Mann Lake	Vilas	C	6.8 ft	18 ft	52
70	Mud Lake	Polk	C	4.3 ft	15 ft	53
71	Big Arbor Vitae Lake	Vilas	C	6 ft	41 ft	51
72	Little Sand Lake	Barron	C	4.8 ft	39 ft	53
73	Lake Esadore	Taylor	C	4.5 ft	36 ft	52
74	Amnicon Lake	Douglas	C	5 ft	31 ft	52
75	White Lake	Waupaca	C	5.6 ft	10 ft	50
76	Stella Lake	Vilas	C	5 ft	9 ft	53
77	Diamond Lake	Oneida	C	3.5 ft	17 ft	55
78	Ward Lake	Polk	C	6 ft	43 ft	50
79	Druid Lake	Washington	C	5.5 ft	53 ft	51
80	Whitewater Lake	Walworth	C	4 ft	35 ft	54
81	Big Dardis Lake	Price	C	5.5 ft	-	50
82	Laurel Lake	Oneida	C	3.7 ft	-	54
83	School Section Lake	Waukesha	C	6.2 ft	8 ft	51
84	School Section Lake	Waupaca	C	6.5 ft	38 ft	50
85	Wood Lake	Burnett	C	5.5 ft	35 ft	51
86	Big Trade Lake	Burnett	C	5 ft	39 ft	53
87	Hancock Lake	Oneida	C	5.4 ft	22 ft	52
88	Deep Hole Lake	Langlade	C	9 ft	-	51
89	Deep Hole Lake	Oneida	C	4.3 ft	-	52
90	White Mound Lake	Sauk	C	5.5 ft	16 ft	52
91	Black Oak Lake	Langlade	C	4.3 ft	34 ft	54
92	Random Lake	Sheboygan	C	4.5 ft	22.2 ft	52
93	Baker Lake	Vilas	C	4.5 ft	21 ft	54
94	Shawano Lake	Shawano	C	5.9 ft	39.5 ft	52
95	Chute Pond at	Oconto	C	6 ft	19 ft	52
96	Big Stone Lake	Oneida	C	4.2 ft	57 ft	53
97	Wiscobee Lake	Oconto	C	5.7 ft	40 ft	50
98	Pine Lake	Forest	C	4.8 ft	15 ft	53
99	Moon Lake	Barron	C	-	5 ft	57
100	Milwaukee Harbor Lake	Milwaukee	C	8.2 ft	-	52

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 →All Wisconsin lakes →

Source: EPA National Aquatic Resource Surveys, 2026.