Upper South Branch BMP Strategic Implementation
Portions of the South Branch of the Buffalo River are currently overloaded with sediment. Two primary waterways in the watershed, Deerhorn Creek and the South Branch, are listed as impaired for turbidity. Due to sediment deposition in the channel, the waterways have lost much of their capacity. Historical attempts by landowners and others to restore the capacity of the channel by removing sediment have had limited success due to additional excess sediment being washed into the channel.
The project addresses a 155 square mile watershed. LiDAR terrain analysis will be used over the entire watershed area to identify existing and potential areas of high sediment contributions (i.e. gullies). The analysis will target the best locations for measures to reduce sediment loads and runoff. This analysis will help identify and rank high priority areas for installation of soil conservation practicess such as sediment control basins and side inlet structures. Both of these methods will reduce the peak discharge rate of the watershed by storing runoff in the watershed. Also, by temporarily storing the water within the contributing watershed, these practices will reduce the sediment and nutrient loads traveling downstream.
The Buffalo-Red River Watershed District has partnered with the Wilkin and West Otter Tail SWCDs to complete this project. This initial phase will result in a best management practices (BMP) implementation plan along with some construction of side inlets, sediment basins, and other BMPs. Future phases will be primarily geared towards funding BMP installation and landowner coordination.
Nicole Clapp
(i) $1,250,000 the first year and $1,500,000 the second year are for targeted nonpoint restoration technical assistance and engineering. At least 93 percent of this amount must be made available for grants (2011 - Restoration Technical Assistance); (b) $2,800,000 the first year and $3,124,000 the second year are for grants to watershed districts and watershed management organizations for: (i) structural or vegetative management practices that reduce storm water runoff from developed or disturbed lands to reduce the movement of sediment, nutrients, and pollutants or to leverage federal funds for restoration, protection, or enhancement of water quality in lakes, rivers, and streams and to protect groundwater and drinking water; and (ii) the installation of proven and effective water retention practices including, but not limited to, rain gardens and other vegetated infiltration basins and sediment control basins in order to keep water on the land. The projects must be of long-lasting public benefit, include a local match, and be consistent with TMDL implementation plans or local water management plans. Watershed district and watershed management organization staff and administration may be used for local match. Priority may be given to school projects that can be used to demonstrate water retention practices. Up to five percent may be used for administering the grants. (2011 - Runoff Reduction)
This initial phase will result in a best management practices (BMP) implementation plan along with some construction of side inlets, sediment basins, and other BMPs.
The BRRWD produced a conservation practices implementation plan which was provided to the Wilkin and West Otter Tail SWCDs for their aid in marketing to landowners. Both SWCDs made numerous landowner contacts. The project resulted in the installation of nine water and sediment control basins and 17 side inlet sediment controls on Wilkin County Ditches Nos. 40, 41, 43, and 44. Sediment reduction is estimated at 358 tons per year and Phosphorus reduction is estimated at 400 pounds per year as a result of this project.