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ITEM 12. WATER RESOURCES: WETLANDS <br />Item Mitigation Description <br />No. <br />12.1 Wetland Sequencing - Minnesota Rules 8420, also known <br />as the Wetland Conservation Act (WCA), requires specific <br />steps (sequencing) be taken when evaluating mitigation for <br />unavoidable wetland impacts. <br />12.2 Stormwater Outfall to the Mississippi River: <br />• Reduce Frequency of Stormwater Discharge, Lower <br />Magnitude ofPeak Flow Rates: The project <br />incorporates a variety of strategies to lower increases <br />in stormwater rate and volume. While all stormwater <br />conveyance features are designed to accommodate <br />the 100-year runoff event without taking infiltration <br />into consideration, on -site retention and infiltration <br />can be incorporated at multiple scales into the <br />development during the detailed design phase for <br />smaller storm retention. Peak flow rates for the 100- <br />year, 24-hour runoff and 100-year, 10-day snowmelt <br />events are 25.1 cfs and 25.3 cfs respectively. <br />• Oversize Culvert and Reduced Slope at Outfall: The <br />last section of culvert will be enlarged from <br />2linches to 36-inches and include an apron and rip - <br />rap to lower velocities and dissipate the energy at the <br />discharge point. This will minimize the potential for <br />2013 Update 2018 Update <br />This activity has occurred and No change. <br />will continue to occur. The <br />wetland mitigation plan has been <br />modified from the original AUAR <br />concept but has been permitted in <br />compliance with WCA and this <br />AUAR update reflects those <br />changes. <br />The City will continue to work to <br />implement this measure <br />The City will continue to work to <br />implement this measure <br />This item has been completed. N/A <br />The outlet to the Mississippi <br />River was installed in 2009. <br />5 Mitigation Plan Update - 2018 September 2018 <br />