What are hypereutrophic lakes in Iowa?

90 hypereutrophic lakes in Iowa. Very high nutrients, dense algae, poor clarity.

What does hypereutrophic mean?

Very high nutrients, dense algae, poor clarity.

Hypereutrophic Lakes in Iowa

Hypereutrophic lakes (TSI above 70) are at the upper end of the productivity scale: visible algal blooms most weeks of summer, clarity often under 3 feet, and meaningful risk of harmful-algal-bloom toxin events. 90 hypereutrophic lakes are on the Iowa books. Almost none of them are deep — 0% break 50 feet. Shallow basin plus heavy nutrient input is the consistent recipe.

Hypereutrophic lakes carry the highest phosphorus and chlorophyll-a readings on record; the trophic class and the readings are measuring closely related dimensions of the same underlying nutrient regime.

#	Lake	County	Clarity	Depth	TSI
1	Big Creek Lake	Polk	2.6 ft	-	65
2	Arrowhead Lake	Pottawattamie	1.8 ft	-	71
3	White Oak Lake	Mahaska	1.4 ft	-	73
4	Crystal Lake Max Depth	Hancock	1.6 ft	-	70
5	Hannen Lake	Benton	1.2 ft	-	76
6	Briggs Woods Lake	Hamilton	1.5 ft	-	70
7	Nelson Lake	Crawford	3.8 ft	-	65
8	Grays Lake	Polk	1.6 ft	-	70
9	Union Grove Lake	Tama	1.6 ft	-	74
10	Casey Lake	Tama	1.2 ft	-	74
11	Littlefield Lake	Audubon	0.9 ft	-	79
12	Meyers Lake	Black Hawk	1.1 ft	-	77
13	Diamond Lake	Poweshiek	1.6 ft	-	69
14	Lake Belva Deer	Keokuk	2.1 ft	-	65
15	Swan Lake Max Depth	Carroll	1.4 ft	-	79
16	Black Pit Lake	Cerro Gordo	5.6 ft	-	60
17	Badger Lake	Webster	2.8 ft	-	66
18	Blue Heron Lake	Polk	2.2 ft	-	68
19	Greenfield Lake	Adair	2.1 ft	-	70
20	Upper Pine Lake	Hardin	1.3 ft	-	72
21	Silver Lake Max Depth	Dickinson	2.7 ft	-	70
22	Silver Lake Max Depth	Delaware	2.4 ft	-	69
23	Twelve Mile Lake	Union	2.4 ft	-	67
24	Sands Timber Lake	Taylor	1.8 ft	-	70
25	Crawford Creek Lake	Ida	1.6 ft	-	70
26	Badger Creek Max Depth Lake	Madison	1.6 ft	-	73
27	Green Valley Lake	Union	1.5 ft	-	71
28	Meadow Lake	Adair	1.7 ft	-	70
29	East Lake Osceola	Clarke	1.2 ft	-	78
30	Lake Iowa	Iowa	1.9 ft	-	68
31	Don Williams Lake	Boone	1.8 ft	-	68
32	Silver Lake	Palo Alto	1.2 ft	-	75
33	Little Wall Lake	Hamilton	0.7 ft	-	77
34	Ellis Lake	Lucas	2 ft	-	66
35	Morris Lake	Lucas	1.6 ft	-	70
36	Fort des Moines Park Pond	Polk	2.8 ft	-	64
37	Lake Orient	Adair	1.3 ft	-	82
38	Lake Anita	Cass	2.2 ft	-	65
39	Roberts Creek Lake	Marion	1.5 ft	-	71
40	Prairie Rose Lake	Shelby	1.6 ft	-	74
41	Lake Miami Max Depth	Monroe	1.3 ft	-	73
42	Summit Lake	Union	1.4 ft	-	71
43	Rodgers Lake	Benton	2.6 ft	-	67
44	South Prairie Lake	Black Hawk	1.6 ft	-	71
45	Center Lake	Dickinson	2.3 ft	-	65
46	Lower Pine Lake	Hardin	1.3 ft	-	75
47	Mckinley Lake	Union	1 ft	-	75
48	Brushy Creek Lake	Webster	2.8 ft	-	64
49	Lake Icaria	Adams	2.7 ft	-	63
50	Rock Creek Max Depth Lake	Jasper	1.1 ft	-	77
51	Red Haw Lake	Lucas	3.1 ft	-	61
52	Cedar Lake	Madison	1.6 ft	-	70
53	Cedar Lake	Linn	0.9 ft	-	80
54	Beaver Lake	Dallas	1.9 ft	-	70
55	Fin And Feather Lake	Cerro Gordo	2.3 ft	-	68
56	Five Island Lake	Palo Alto	1.6 ft	-	69
57	Avenue of the Saints Lake	Bremer	1.2 ft	-	76
58	Spring Lake Max Depth	Greene	0.9 ft	-	71
59	Lake Darling Max Depth	Washington	1.6 ft	-	75
60	Desoto Bend Lake	Harrison	1 ft	-	78
61	Eldred Sherwood Lake	Hancock	3 ft	-	65
62	Lake Manawa	Pottawattamie	1 ft	-	74
63	Big Hollow Lake	Des Moines	1.8 ft	-	70
64	Wilson Lake	Taylor	1.6 ft	-	70
65	Ottumwa Lagoon Max Depth Lake	Wapello	0.9 ft	-	79
66	Fogle Lake	Ringgold	2.3 ft	-	64
67	Arbor Lake Max Depth	Poweshiek	1.3 ft	-	71
68	Lake of Three Fires Max Depth	Taylor	2 ft	-	69
69	Lake Geode	Des Moines	2.1 ft	-	64
70	Browns Lake	Woodbury	0.7 ft	-	79
71	Thayer Lake	Union	3.5 ft	-	63
72	Williamson Pond Max Depth	Lucas	1.6 ft	-	75
73	Indian Lake	Van Buren	1.2 ft	-	75
74	Ingham Lake	Emmet	1.4 ft	-	73
75	Smith Lake	Kossuth	2.4 ft	-	69
76	Lake Sugema	Van Buren	2.3 ft	-	64
77	Lake Hendricks	Howard	1.5 ft	-	73
78	Viking Lake	Montgomery	3.3 ft	-	61
79	Windmill Lake	Taylor	2.5 ft	-	66
80	Little River Lake	Decatur	2.3 ft	-	69
81	Blue Lake	Monona	0.9 ft	-	75
82	Pierce Creek Lake	Page	2.2 ft	-	70
83	Lake Pahoja	Lyon	1.7 ft	-	73
84	Volga Lake	Fayette	2.1 ft	-	67
85	Terry Trueblood Lake	Johnson	1.1 ft	-	74
86	Alice Wyth Lake	Black Hawk	1.6 ft	-	75
87	Lake Fisher	Davis	2 ft	-	67
88	Corydon Reservoir	Wayne	1.9 ft	-	77
89	Humeston Reservoir	Wayne	1.6 ft	-	72
90	Okamanpeedan Lake	Emmet	1 ft	-	75

All hypereutrophic lakes →Minnesota version →Wisconsin version →Illinois version →Michigan 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 Iowa lakes →

Source: EPA National Aquatic Resource Surveys, 2026.