Perch Lake Preparing for Dredging Project, Improve Connection With St. Louis River

DULUTH, Minn. – Perch Lake is located on Duluth’s south side, between New Duluth and Fond du Lac.  The 25-acre body of water used to be a bigger part of the St. Louis River estuary until human intervention occurred.

“It used to have a really nice connection to the St. Louis River before Highway 23 and the railroad went in,” says Jeramy Pinkerton, a project manager with the Minnesota DNR.

The two bodies of water are still connected, but only by a four-foot culvert.  That has led to an increase in sediment in the lake, and a decline in the overall health of the water.

That changes once dredging equipment arrives from the East Coast to begin the first phase of the restoration project.  Approximately 77,000 cubic yard of sediment will be removed and used elsewhere in the Northland.

Pinkerton says the work on the lake will be done below the water’s surface. “So there will be a deeper hole here that will allow for fish to find cooler temperatures in the summer, and allow for more oxygenated water in the lower areas, and then we will be making a steeper transition zone out here that will reduce the biological oxygen demand to help more oxygen stay in the lake in the summer and in the winter.”

The second phase will take place in 2023, when a 12-by-16 foot culvert will be added to connect Perch Lake to the St. Louis River.

Pinkerton says project benefits will extend beyond the health and quantity of fish in the lake. “It will allow aquatic animals, your mink and your beaver and things like that, to make it through all the time.  And it will also allow for smaller boats to make it through, to open Perch Lake up for more of a recreational opportunity for folks who may not be able to get in there now.”

It will also help the overall health of the St. Louis River.  “It’s also going to help us to get to delisting the area of concern on here,” says Pinkerton. “It’s one of the projects for that.  So that’s hugely important as well to just make the river system as a whole healthier and not just Perch Lake.”

By next fall, the area will be restored to what it should look like naturally.  Pinkerton is excited to see how nature will adapt to the changes. “Just going to be exciting to see what sort of fish.  We’ll do sampling out here and see what sort of fish do come back in here and sort of birds utilize this space.  It will be super exciting to get there.”

The project is led by the Minnesota DNR and Minnesota Land Trust, with funding from the Great Lakes Restoration Initiative and the Outdoor Heritage Fund.