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Silver View Pond indicated that the permanent pool volume has been reduced by approximately 38%. The complete results are summarized in Table 1. The city is covered under the MPCA's General NPDES/SDS Permit MNR04000 for Municipal Separate Storm Sewer Systems (MS4) for operation of the city's stormwater management system, and has developed a storm water pollution prevention program (SWPPP) in compliance with the MS4 permit requirements. As part of the city's SWPPP, the city must manage. operate. and maintain the storm sewer system in a mariner to reduce the discharge of pollutants "to the maximum extent practicable." The SWPPP requirements address maintenance of stormwater ponds as part of the following MS4-listed minimum control measures (MCMs): Minimum Control Measure #3. Illicit Discharge Detection and Elimination, which requires cities with MS4 permits to map their storm sewer system, including ponds. lakes, streams, and wetlands connected to the system and identify pond outfalls. + Minimum Control Measure #5: Post Construction Storm grater Management, recognizes that ponds are part of the city's "post construction proggram" and must prevent or reduce water quality impacts. MCM #5 requires that MS4s ensure short- and long-term operation and maintenance of ponds. Minimum Control Measure #6: Pollution Prevention, which requires cities perform the following: o Operate and maintain its stormwater management system in a manner so as to reduce the discharge of pollutants to the maximum extent practicable. o At a minimum, inspect 20% of all outfalls, sediment basins, and ponds each year on a rotating basis. This requirement was developed to ensure the city inspects and maintains or upgrades, as needed, all of its outfalls, basins and ponds at least every 5 years. This report summarizes the assessment of one of the city -owned surface water quality treatment basins. 2.2 Evaluation Process To meet the city's stormwater management needs and to comply with the minimum control measures required by (lie city's MS4 SWPPP, the first pond assessment of a city-wide stormwater pond evaluation program was performed. The evaluation was generally comprised of: 1. Selecting ponds for evaluation. Silver View Pond was selected as a pilot assessment to help the city learn from it and develop its pond assessment and maintenance program. It was selected as it is one of the city's oldest constructed basins and it has not been maintained or monitored to any extent since it was constructed. ?. Evaluating historic information for the selected pond. P. Nip Is 21 MN 62 23ts'1082 Silver View Pond Anmfilvnl WorUile; Reporn SiINet Picµ Popid .Amesw.nrun•F iaai.d�rcr 4