Eutrophic Lakes in Indiana

12 eutrophic lakes in Indiana. 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. 12 Indiana 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	Lost Lake	Marshall	D	4.9 ft	-	54
2	Koontz Lake	Starke	D	4.9 ft	-	54
3	Lake Wawasee	Kosciusko	D	5.9 ft	-	52
4	Webster Lake	Kosciusko	D	5.6 ft	-	52
5	James Lake	Kosciusko	D	5.3 ft	-	53
6	Monroe Lake	Monroe	D	5.7 ft	-	52
7	Winona Lake	Kosciusko	F	2.8 ft	-	62
8	Yellow Creek Lake	Kosciusko	F	2.8 ft	-	62
9	Pike Lake	Kosciusko	F	1.9 ft	-	68
10	Beaver Dam Lake	Kosciusko	F	3.1 ft	-	61
11	Big Barbee Lake	Kosciusko	F	3.1 ft	-	61
12	Lake Lemon	Monroe	F	2.1 ft	-	66

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

Source: EPA National Aquatic Resource Surveys, 2026.