Shingle Creek SRP Reduction Project
Wetlands that have received many decades of nutrient and sediment-rich runoff from agricultural and developed land uses are at risk of transforming from nutrient sinks to nutrient sources. The hydrology of these wetlands has also often been altered, making them more susceptible to sediment nutrient release under anoxic conditions. The discharge from these altered wetlands is often high in soluble reactive phosphorus (SRP) and low in dissolved oxygen. SRP is the phosphorus form that is directly taken up by algae and other plants
In the Shingle Creek watershed, where nearly all of the remaining wetlands are highly disturbed and altered, these high concentrations of SRP can negatively impact downstream lakes and streams. The SRP Reduction Project tested three media in filters built into the outlet weir at the outlet of a wetland in Crystal known by its DNR number, 639W. This wetland is directly upstream of Upper Twin Lake. Flow through the filters was metered, and water quality samples taken just upstream and from the outlets of each of the three filters were analyzed to determine which medium performed the best at reducing SRP.
2019 Project Results
Funding for this project was provided by the Minnesota Pollution Control Agency through a Grant from the United States Environmental Protection Agency, Section 319 Nonpoint Source Management Fund.