Green Lake Stormwater Quality Improvement Project (BWSR Legacy Grant)
- Grant timeline March 2012 – December 2014
- Grant dollars: $252,125 Match: $66,175 Total: $318,300
- Despite water quality that is substantially better than ecoregion averages, monitoring data collected on Green Lake in recent years indicates that the lake’s water quality is on the verge of not meeting the goal of ‘non-degradation’ that was established in 2002. In 2009, the lake actually failed to meet the goal for the first time. The risk of sliding into a “degradation” status, the first-time discovery of large masses of floating vegetation in 2011, and therapid spread of an aquatic invasive plant (Eurasian watermilfoil) in a lake once determined to not be at risk begs the question: what has changed? Over recent decades, development in the City of Spicer and around Green Lake has increased dramatically, resulting in much higher percentages of imperviousness. The impervious surfaces represent a clear threat to the lake from the resulting change in hydrology; increased runoff velocities and volumes necessitate the incorporation of stormwater infrastructure to accommodate water that previously infiltrated soils. The infrastructure provides for efficient removal of water from properties and streets, but it also results in the efficient delivery of the sediment, nutrients, and other pollutants that typically accompany stormwater. The Green Lake Stormwater Quality Improvement Project is designed by the Middle Fork Crow River Watershed District (MFCRWD) and project partners to provide retrofitted solutions to the water volume and water quality issues threatening this priceless resource. Five initiatives will be implemented, including the daylighting of a newly developed riffle and pool lined channel, a raingarden/biofiltration program to accompany the channel, a parking lot retrofit designed to treat first flush pollutants, a biofiltration cell and hydrodynamic separator to enhance a previously installed BMP, and the stabilization of a heavily eroded channel due to stormwater influences.