What is the cleanest lake in Brown County, Minnesota?

Sleepy Eye Lake in Brown County is the highest-rated lake in Brown County, Minnesota with an EPA water quality grade of C and 3.3 feet of water clarity.

How are these rankings calculated?

Lakes are graded A through F on nutrients and algae — total phosphorus, nitrogen, chlorophyll-a, and turbidity — against EPA National Lakes Assessment 2022 condition classes for that lake’s ecoregion. Water clarity (Secchi depth) is measured and shown; it is not the letter. Lakes without enough recent samples are UNRATED, not given an F. Source data comes from the EPA Water Quality Portal.

Cleanest Lakes in Brown County, Minnesota

Sleepy Eye Lake in Brown County leads the rankings with a water quality grade of C and 3.3 ft of clarity. Below are the top 12 cleanest monitored lakes in Brown County, Minnesota, ranked by EPA water quality score.

Ranked List

#	Lake	County	Grade	Clarity	Phosphorus	Algae
1	Sleepy Eye Lake	Brown	C	3.3 ft	39.5 µg/L	18.7 µg/L
2	Clear Lake	Brown	F	0.8 ft	196 µg/L	92.8 µg/L
3	Wellner-Hageman Reservoir	Brown	F	3.7 ft	45 µg/L	30.3 µg/L
4	Hanska Lake	Brown	F	1 ft	219 µg/L	98.8 µg/L
5	Linden Lake	Brown	NR	-	-	-
6	Juni Lake	Brown	NR	-	-	-
7	School Lake	Brown	NR	-	-	-
8	Zanders Lake	Brown	NR	-	-	-
9	Gilman Lake	Brown	NR	-	-	-
10	Bachelor Lake	Brown	NR	-	-	-
11	Altermatt Lake	Brown	NR	-	-	-
12	Boise Lake	Brown	NR	-	-	-

Ranked List

More Answers for Brown County, Minnesota