Peshtigo River Hemlock Curve Project nears completion

PESHTIGO – The Marinette County Land and Water Conservation Division has been working with various partners since 2021 to make the Peshtigo River Hemlock Curve Project a reality.

An initial grant to improve fish passage and pike spawning habitat in streams and ditches along the bay provided the momentum to protect the 640 feet of eroding streambank at the downstream part of the curve.

The following year, the project expanded to nearly 1,540 feet when the upstream landowner agreed to participate in the project. The plan then included removing the concrete that had been dumped in the river years ago to control shoreline erosion.

The project was funded by grants and resources from several private and governmental sources including the U.S. Environmental Protection Agency’s Great Lakes Restoration Initiative Grant, U.S. Fish and Wildlife Service, National Oceanic and Atmospheric Administration, Coastal States Organization, Wisconsin Department of Natural Resources (DNR), Fund For Lake Michigan, Marinette County and the Fox River Trustee Council, which also provides funding for smaller fish passage and northern pike habitat projects.
The initial plan for Hemlock Curve was to use traditional large riprap on 640 feet of eroding shoreline on DNR property.

This quickly evolved into a more habitat friendly plan that included rock sized for fish spawning, stream vanes to deflect currents away from the bank and using root wads to add cover and habitat complexity.

Trees harvested from the site were tipped out of the ground and the root balls with 20 feet of tree trunk were buried in the streambank with the roots sticking out into the river. The root wads provide additional cover along the shoreline and disrupt the current.

In addition, instead of running stone to the top of the high bank, the steep upper bank will be sloped back and planted with shrubs and plants to provide upland habitat for wildlife and to improve access for nesting turtles.

With the walleye run starting to pick up speed, anglers who venture downstream from Peshtigo are going to see some big changes along the river.

While the river was frozen last winter, most of the in-stream work was completed for a large habitat improvement project located just downstream from the Peshtigo Wastewater Treatment Facility. Most anglers would know the site for the long stretch of shoreline that was armored with concrete slabs and other demolition waste.

One of the first things boaters and anglers will notice as they approach the site is that most of the large trees on the shoreline have been removed.

Unfortunately, this was necessary to allow access for heavy machinery to remove the concrete slabs and grade the upper bank.

Along the DNR land, most of the trees that had fallen in the river were removed so the spawning rock could be installed. While these trees did provide important cover for fish, the Peshtigo River is not lacking for woody habitat but is short on rocky areas for spawning.

The Marinette County Land and Water Conservation Division shared that boaters need to be aware of the four rock stream vanes — or barbs — that have been constructed.

These long sloping fingers of rock stick out into the river at an upstream angle. Water flowing over the vane is redirected away from the bank towards the middle of the stream. The vanes also provide excellent spawning habitat for fish as the current washing over them keeps the stone clean.

During periods of low water boaters will be able to see the vanes from the surface. During periods of high flow most of the vanes will be submerged.

Rock used in the project was selected to attract spawning gamefish and great lakes sturgeon. Some areas are covered with rounded cobble-sized stone while others have smaller angular limestone. Much of the rock is underwater where it protects the toe of the slope. Native vegetation will be relied on to protect the bank above the flood elevation.

This spring, native shrubs will be planted along the upper edge of the rock.
The sandy upper bank will be covered with topsoil and planted with a mix of native grasses and wildflowers.

On the DNR land, a section of shoreline along the Hemlock Curve Nature Trail will be graded to a gentle slope to allow for easy walking access down to the water. As the site recovers, aquatic insects, crayfish and gamefish will make the new habitat their home and fish running upstream from the bay will find a new place to spawn.