Knife River Sediment Reduction

The Knife River is a popular trout fishing river along the North Shore of Lake Superior. In 1998, it was listed as "impaired" by the MPCA for turbidity (being too muddy). In 2010, a Total Maximum Daily Load, or, water clean-up plan was approved. The major recommendations were to address peak flows (fast
water running through the stream channel during and after rain storms or snow melt) and eroding clay streambanks contributing sediment to the river. Through this grant, the South St. Louis Soil & Water Conservation District is working with partners to implement strategies that will help restore the water quality of the Knife and get it off the impaired waters list. Over the past year, the district has been meeting with many people to identify locations for projects to reduce peak flows in the river by tree planting, ditch checks, and other stormwater management practices.

It takes time and repeated visits with landowners concerned about their river but the district has completed the following as of January 2011: 1) Identified and secured permission from landowners to plant 7,500 feet of white pine and tamarack along the river. Conifers serve the river both in life and death. In life, they provide shade to the stream (trout require cooler waters to survive) and when they die, they fall into the river creating snags which provide excellent trout habitat and also serve as speed bumps for slowing down water, 2) Secured cooperation with County officials to install 30 ditch checks in appropriate low-gradient ditches to help hold back water, and 3) Cooperated with a neighboring SWCD and two private landowners to stabilize an eroding bank that is contributing sediment to the river. In addition, the district has leveraged interest in the project to attract additional funding to install a rain garden to infiltrate runoff at the Knife River Recreational Center.