Eutrophic Lakes in Illinois

84 eutrophic lakes in Illinois. 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. 84 Illinois lakes register as eutrophic. Only 0% 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	Opeka Lake	Cook	B	3.9 ft	-	51
2	One Horse Gap Lake	Pope	B	4 ft	-	51
3	Tecumseh Lake	Hardin	B	3.6 ft	-	52
4	Grays Lake	Lake	B	3.5 ft	-	52
5	Lily Lake	McHenry	B	3.3 ft	-	52
6	Catherine Lake	Lake	B	7.4 ft	-	50
7	Vienna Correctional Center Lake	Johnson	C	4.5 ft	-	51
8	Pounds Hollow Lake	Gallatin	C	3.9 ft	-	54
9	George Lake	Rock Island	C	4.2 ft	-	53
10	Shabbona Lake	DeKalb	C	4.9 ft	-	53
11	Channel Lake	Lake	C	8 ft	-	51
12	Palmyra-Modesto Lake	Macoupin	C	-	-	62
13	Lake of Egypt	Williamson	C	3.2 ft	-	56
14	Sag Quarry East Lake	Cook	C	5.4 ft	-	53
15	Turtlehead Lake	Cook	C	2.8 ft	-	55
16	Sag Quarry West Lake	Cook	C	4.2 ft	-	59
17	Olney East Fork Lake	Richland	C	3.2 ft	-	56
18	Woods Creek Lake	McHenry	C	3.9 ft	-	58
19	Lake Opeka	Cook	D	4 ft	-	57
20	Consumers Quarry Lake	Cook	D	6.5 ft	-	50
21	Lake Arlington	Cook	D	4.5 ft	-	55
22	Great Lakes Quarries East	Cook	D	4.5 ft	-	55
23	Flatfoot Lake	Cook	D	6 ft	-	51
24	Papoose Lake	Cook	D	5 ft	-	54
25	Maple Lake	Cook	D	5 ft	-	54
26	Horsetail Lake	Cook	D	5 ft	-	54
27	Sag Quarry-West Lake	Cook	D	5.5 ft	-	53
28	Doughnut Lake	Cook	D	5 ft	-	54
29	Busse Lake Main Pool	Cook	D	3.5 ft	-	59
30	Lake Glenview	Cook	D	3.3 ft	-	60
31	Pogie Lake	Cook	D	3.5 ft	-	59
32	Columbia Basin Lake	Cook	D	6 ft	-	51
33	Jackson Park Inner Harbor Lake	Cook	D	5 ft	-	54
34	Turtlehead Lake	Cook	D	6 ft	-	51
35	Jackson Park West Lagoon Lake	Cook	D	5 ft	-	54
36	Jackson Park Outer Harbor Lake	Cook	D	6 ft	-	51
37	South Pond	Cook	D	5.3 ft	-	53
38	Jackson Park East Lagoon Lake	Cook	D	5 ft	-	54
39	Long Lake	Lake	D	3.4 ft	-	61
40	Arrowhead Lake	Cook	D	2.1 ft	-	60
41	Bullfrog Lake	Cook	D	1.4 ft	-	65
42	Hastings Lake	Lake	D	3.4 ft	-	59
43	Horsetail Lake	Cook	D	2.2 ft	-	61
44	Galena Lake	Jo Daviess	D	5.2 ft	-	53
45	Dutchman Lake	Johnson	D	2.1 ft	-	61
46	Randolph Lake	Randolph	D	1.7 ft	-	65
47	Wayne City Lake	Wayne	D	2.1 ft	-	61
48	Tampier Lake	Cook	D	1.7 ft	-	63
49	Poss Lake	DuPage	D	1.2 ft	-	65
50	Midlothian Lake	Cook	D	1.2 ft	-	67
51	Sparta Northwest Lake	Randolph	D	2.6 ft	-	59
52	Sara Lake	Effingham	D	2.2 ft	-	63
53	Otter Lake	Macoupin	D	1.8 ft	-	62
54	Grass Lake	Lake	D	1.4 ft	-	67
55	Jacksonville Lake	Morgan	D	1.8 ft	-	64
56	Long Lake	Lake	D	2.9 ft	-	60
57	Fox Lake	Lake	D	1.9 ft	-	63
58	Petite Lake	Lake	D	2.5 ft	-	60
59	Canton Lake	Fulton	D	2.5 ft	-	62
60	Nippersink Lake	Lake	D	1.3 ft	-	66
61	Kinmundy New Lake	Marion	D	2.9 ft	-	59
62	Charleston Side Channel Lake	Coles	D	-	-	64
63	Loveless Lake	Macoupin	D	-	-	64
64	Greenfield Lake	Greene	D	-	-	65
65	Forbes Lake	Marion	D	1.4 ft	-	69
66	Mermet Lake	Massac	D	1.6 ft	-	68
67	Centralia Lake	Marion	D	1.5 ft	-	70
68	Wesslyn Cut Lake	Perry	D	4.5 ft	-	64
69	Newton Lake	Jasper	D	1.7 ft	-	69
70	Marie Lake	Lake	D	2.7 ft	-	64
71	Monee Lake	Will	D	4.9 ft	-	64
72	Vernor Lake	Richland	D	4.8 ft	-	62
73	Pistakee Lake	McHenry	D	2.7 ft	-	63
74	Lake Charlemagne	Cook	F	2 ft	-	67
75	Great Lakes Quarries West	Cook	F	2.5 ft	-	64
76	Bull Frog Lake	Cook	F	3 ft	-	61
77	Crabtree Lake	Cook	F	2 ft	-	67
78	North Pond	Cook	F	2.5 ft	-	64
79	Tampier Lake	Cook	F	2 ft	-	67
80	Big Marsh Park Ne Lake	Cook	F	2.3 ft	-	65
81	Columbus Park Lagoon Lake	Cook	F	2.5 ft	-	64
82	Marquette Park Lagoon Lake	Cook	F	3 ft	-	61
83	Burnham Prairie Marsh West Lake	Cook	F	3.1 ft	-	61
84	Lake Calumet	Cook	F	3 ft	-	61

All eutrophic lakes →Minnesota version →Wisconsin version →Michigan version →Iowa version →Ohio version →Pennsylvania version →New York version →Missouri version →Indiana version →North Dakota version →South Dakota version →All Illinois lakes →

Source: EPA National Aquatic Resource Surveys, 2026.