How are these rankings calculated?

Lakes are graded A through F using the Metropolitan Council methodology, which combines Secchi depth (water clarity), total phosphorus, and chlorophyll-a (algae) into a single score. Source data comes from the EPA Water Quality Portal.

Cleanest Lakes in Oglala Lakota County, South Dakota

No qualifying lakes in Oglala Lakota County, South Dakota matched this filter.

Cleanest Lakes in Oglala Lakota County, South Dakota

More Answers for Oglala Lakota County, South Dakota