Coon Lake Area Stormwater Retrofits

This project will install new stormwater treatment practices in neighborhoods directly draining to Coon Lake. The objective is to remove phosphorus, which fuels algae growth, before the water is discharged into the lake. Seventeen potential project sites have been identified and ranked and include curb-cut rain gardens, swales, stabilizing stormwater discharge points, and a basin outlet modification.

The Anoka Conservation District will install a subset of approximately seven of the candidate projects in order of cost effectiveness. At a minimum, this project will reduce total phosphorus inputs to Coon Lake by 4 pounds per year, total sediment input by one ton per year, and runoff volume by 2.0 acre-feet per year.

Coon Lake is a priority for Anoka County. It is the county's largest lake, is the feature of one county park, has two public boat accesses, and is a focus of the community. Water quality improvement is necessary because the lake is approaching the state water quality standard. As a result, the Sunrise River Watershed Management Organization, the City of East Bethel, and three lake-focused groups are committing resources to this project.