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process used for this pond should be used for additional ponds in future phases of the city-wide pond <br />assessment. Also, this pond assessment process should be repeated on Silver View Pond in several <br />years to determine Elie ongoing rate of sedimentation and the water quality effectiveness of the pond. <br />As will be described in detail, the assessment performed for Silver View Pond resulted in the <br />following, findings: <br />• Approximately 38% of the originally excavated pond volume is filled with sediment. <br />• The basin was, in all likelihood, built in what was a natural wetland. <br />■ There remains ample volume in the basin to meet MPC'A minimum guidelines. <br />• The basin's treatment efficiency could be improved by removal of the accumulated sediment. <br />modification of the basin's outlet structure, or both. <br />■ There is the potential for short-circuiting* in the basin due to the close proximity of storm <br />sever inlets to the outlet of the basin. <br />• There are several basin maintenance items that need to be attended to in a relatively short <br />time frame. <br />Recommended actions for the city to consider include: <br />1. Performing an analysis of the pond's sediment to determine its level of contamination and <br />better understand the possible costs to remove the accumulated sediment. <br />2. Applying for a cost share grant from the Rice Creek Watershed District for pond maintenance <br />and modifications. <br />3. At a minimum, consider modifying the pond's outlet to provide extended detention of the <br />1-year to 2-year, 24-hour event, and in turn improving on the basin's treatment efficiency. <br />4. Commit to re -assessing the pond at least once every 5 years (this is consistent with the city's <br />current MS4 permit'). <br />5. Consider monitoring the pond to document its treatment efficiency and demonstrate Mounds <br />View's commitment to anti -degradation of waters leaving the city. <br />b. Consider attending to the basic maintenance items described in Section 4.2 of this report. <br />P: Mpls 23 Ath (42 23h21092 Sil+er VjeA Pond hs.. to nl Work il�, kvporl Sihia Vim Pond hsscssmrnl-rin;,IA,c4 3 <br />