Big Trout Lake Stormwater Management Design Project By Hannah Rollin

Problem  Valuable Trout Lake for the state of Minnesota  Excess sediment and stormwater flows directly into the lake due to the current curb and gutter system and the culvert  Increasing temperature of the lake and decreasing the clarity  Valuable Trout Lake for the state of Minnesota  Excess sediment and stormwater flows directly into the lake due to the current curb and gutter system and the culvert  Increasing temperature of the lake and decreasing the clarity

Constraints  Limited land area available  Snowmobile route  Steep slopes (instability)  Limited land area available  Snowmobile route  Steep slopes (instability)

Field Assessment  Surface and groundwater measurements  Temperature  Salinity  Soil type assessment  General land type observations  Surface and groundwater measurements  Temperature  Salinity  Soil type assessment  General land type observations

Proposed Solution  Use a vortex separator to remove sediment from the stormwater  Downstream Defender®  The vortex system forces particles to settle into the sump  Efficient and easy to maintain  Small footprint  System of Perforated Pipes  Infiltration of stormwater will aid in temperature reduction  Use a vortex separator to remove sediment from the stormwater  Downstream Defender®  The vortex system forces particles to settle into the sump  Efficient and easy to maintain  Small footprint  System of Perforated Pipes  Infiltration of stormwater will aid in temperature reduction

Watershed and Drainage Assessment  Delineate the watershed in GIS  Calculate drainage area:  Grass/Vegetated area: 167,277ft 2  Paved area: 156,722 ft 2  Calculate runoff from precipitation data  37,040 ft 3  Delineate the watershed in GIS  Calculate drainage area:  Grass/Vegetated area: 167,277ft 2  Paved area: 156,722 ft 2  Calculate runoff from precipitation data  37,040 ft 3

Final Design  Two 4ft Downstream Defenders (each can handle 8cfs)  12 perforated pipes, 2ft in diameter  Two 4ft Downstream Defenders (each can handle 8cfs)  12 perforated pipes, 2ft in diameter

Next Steps  Research possibility of installing larger pipes for larger storage volume  Survey elevations to calculate gradients of pipes  Cost analysis  Questions?  Research possibility of installing larger pipes for larger storage volume  Survey elevations to calculate gradients of pipes  Cost analysis  Questions?