South Central Technical Service Area (SCTSA) will use this Clean Water Fund grant to provide Soil and Water Conservation Districts and other local organizations in its eleven-county area with a Geographic Information System (GIS) Technician to assist in using available GIS information to target specific locations where Best Management Practices (BMPs) can be installed to help improve water quality.
This project will layer hydrologic, hydraulic, geomorphic, and pollutant loading analysis with existing countywide PTMApp outputs to identify the four highest priority areas for BMP implementation in an eastern Nicollet County ravine system experiencing dramatic mass wasting events. Three alternatives for each priority site will be presented, including an evaluation of water quality benefit, construction costs, and a cost-benefit summary.
Nicollet County is located in south central Minnesota and is bordered on two sides by the Minnesota River. A line of forested bluffs separate the river valley from land that is relatively flat and historically used for agricultural purposes. Approximately 245,000 acres of the County are actively farmed. The 2012 impaired waters list for water bodies located in Nicollet County include the Minnesota River, Seven Mile Creek, Rogers Creek and tributaries to the Rush River.
Seven Mile Creek is a direct tributary to the Minnesota River in south-central Minnesota. It drains heavily tiled agricultural land in its upper watershed and meanders through a forested valley as a spring-fed trout stream within Nicollet County's premier park.
This project aims to significantly reduce the amount of sediment transfer from eroding bluff areas to Seven Mile Creek during spring snowmelt and rain events throughout the year. This will be accomplished by installing and maintaining drop structures and reinforcing the existing spalsh pool at the outlet pipe without destabilizing the surrounding bluffs. When applied in tandem, this project will reduce the peak flow rate to ravine areas while shielding and protecting the bluff itself from eroding.