Laserfiche WebLink
<br />RCWD Alternative Compliance Sequencing Report <br />City of St. Anthony Village PAGE 24 <br />WSB Project No. 1626-53 <br /> <br />2. Mirror Lake Pond Water Quality and Habitat Improvements (RC Ditch <br />3 Watershed) <br /> <br />Project Description: <br />This project includes increasing the depth of Mirror Pond and providing <br />topographic features in the lake to aid in pollutant removal. The project also <br />includes enhancement of fish and wildlife habitat by planting native <br />vegetation along the shoreline. <br /> <br />Project Benefit: <br />The existing pond removes approximately 58% of total phosphorus or 78 <br />pounds annually. The proposed project is anticipated to increase the <br />removal efficiency of total phosphorus to 61% which would result in <br />removal of an additional 4 pounds of total phosphorus annually. Using the <br />anticipated loading rate from the Silver Lake TMDL (0.97 lbs of TP/AF of <br />runoff), an equivalent annual volume reduction of 169,012 cubic feet is <br />estimated. <br /> <br />3. Mirror Lake Pond Alum Treatment System (RC Ditch 3 Watershed) <br /> <br />Project Description: <br />This project includes a permanent alum treatment system in Mirror Pond <br />which is located on the eastern border of the City. The alum treatment <br />system would remove additional phosphorus to improve both the water <br />quality in the pond as well as stormwater discharged downstream. <br /> <br />Project Benefit: <br />After water quality and habitat improvements described above, the pond will <br />remove approximately 61% of total phosphorus or 82 pounds annually. The <br />proposed project is anticipated to increase the removal efficiency of total <br />phosphorus to 90% which would result in removal of an additional 38 <br />pounds of total phosphorus annually. Using the anticipated loading rate <br />from the Silver Lake TMDL (0.97 lbs of TP/AF of runoff), an equivalent <br />annual volume reduction of 1,605,622 cubic feet is estimated.