What is the cleanest lake in Sully County, South Dakota?

Fuller Lake in Sully County has the cleanest nutrient and algae readings in Sully County, South Dakota.

How are these rankings calculated?

Nutrients and algae, total phosphorus, nitrogen, chlorophyll-a and turbidity, are read against EPA National Lakes Assessment 2022 condition classes for that lake’s ecoregion. Water clarity (Secchi depth) is measured and shown separately. Lakes without enough recent samples are listed without a condition class rather than ranked low. Source data comes from the EPA Water Quality Portal.

Cleanest Lakes in Sully County, South Dakota

Fuller Lake in Sully County leads the rankings on measured clarity and nutrients. Below are the top 5 cleanest monitored lakes in Sully County, South Dakota, ranked on EPA nutrient and algae measurements.

Ranked List

#	Lake	County	Clarity	Phosphorus	Algae
1	Fuller Lake	Sully	-	-	-
2	Lake Okobojo	Sully	-	-	-
3	Walker Lake	Sully	-	-	-
4	Durrstein Lake	Sully	-	-	-
5	Warnes Slough	Sully	-	-	-

Ranked List

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