Question 1

Cleanest Lakes in Buchanan County, Iowa?

Accepted Answer

Lake Oelwein in Buchanan County leads the rankings on measured clarity and nutrients. Below are the top 1 cleanest monitored lakes in Buchanan County, Iowa, ranked on EPA nutrient and algae measurements.

Question 2

What is the cleanest lake in Buchanan County, Iowa?

Accepted Answer

Lake Oelwein in Buchanan County has the cleanest nutrient and algae readings in Buchanan County, Iowa.

Question 3

How are these rankings calculated?

Accepted Answer

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 Buchanan County, Iowa

Ranked List

More Answers for Buchanan County, Iowa