Erickson Group Streambank Stabilization
The Thief River is impaired due to low Dissolved Oxygen and high Turbidity levels resulting from high sediment load. These impairments affect the drinking water supply of Thief River Falls in addition to fish spawning habitat and recreation. The Erosion, Sedimentation and Sediment Yield Report completed in 1996 found that 63% of the sediment originates from the streambank of the Thief River. The Pennington Soil and Water Conservation District is therefore targeting the major sediment sources along the river.
The Pennington SWCD and the Red Lake Watershed District have a long history of working together to install conservation practices. This project will stabilize 1700' of river bank and reduce sedimentation from the project area by nearly 100%. The reduction in sediment will also reduce the pace the Thief River Falls Reservoir is filling in and losing capacity. In the past, it was estimated the
reservoir would require dredging every 50 years. The last dredging was needed only 35 years later and it appears the reservoir is speeding towards the next dredging at an even faster pace. Treatment of this water for drinking is a major expense to the City. Reducing pollutants will be a benefit to those costs and the residents of Thief River Falls.
The site was surveyed the summer of 2010. The Red River Valley Conservation Service Area is currently working on the project design and construction is scheduled to begin the summer of 2011.
(g) $2,330,000 the first year and $1,830,000 the second year are for grants to implement stream bank, stream channel, and shoreline protection, and restoration projects to protect water quality. Of this amount, $330,000 the first year and $330,000 the second year may be used for technical assistance and grants to establish a conservation drainage program in consultation with the Board of Water and Soil Resources and the Drainage Work Group that consists of pilot projects to retrofit existing drainage systems with water quality improvement practices, evaluate outcomes, and provide outreach to landowners, public drainage authorities, drainage engineers and contractors, and others. Of this amount, $500,000 the first year is for a grant to Hennepin County for riparian restoration and stream bank stabilization in the ten primary stream systems in Hennepin County in order to protect, enhance, and help restore the water quality of the streams and downstream receiving waters. The county shall work with watershed districts and water management organizations to identify and prioritize projects. To the extent possible, the county shall employ youth through the Minnesota Conservation Corps and Tree Trust to plant trees and shrubs to reduce erosion and stabilize stream banks. This appropriation must be matched by nonstate sources, including in-kind contributions (2010 - Shoreland Improvement)
1,700 linear feat of streambank and shoreline protection were installed, yielding an estimated reduction of 119 tons/yr of sediment and 137 lbs/yr of phosphorus.