Bemidji State University Subsurface Stormwater Water Quality Treatment

As a part of the Mississippi Headwaters Stormwater Retrofit Analysis, a feasibility study was conducted on the Bemidji State University property to determine possible subsurface water quality best management practices options. Staff from Beltrami SWCD, in cooperation with the City of Bemidji and Bemidji State University, are proposing to install a subsurface stormwater treatment system to reduce Total Suspended Solids (TSS) and Total Phosphorus (TP) loading to Lake Bemidji and subsequently the Mississippi River. The analysis modeled the stormwater watershed and determined the current loading for TSS is 30,868 lbs/year, and the load for TP is 100.5 lbs/year. Our goal for this watershed is to remove 80% of the TSS and 60% of the TP. The stormwater treatment system will be installed on a City trunk stormwater line that outlets to Lake Bemidji. We anticipate removing 77% of the TSS or 22,841 lbs/year and 60% of the TP or 58.0 lbs/year, resulting in achieving our TP goal and very close to our TSS goal. In addition, this project will help us towards achieving 25% of the 224 lbs-TP/year reduction goal for Lake Bemidji set in the Mississippi River Headwaters Watershed Comprehensive Plan.