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downstream to the pond in the SE corner of Fairview and C, increasing the high water elevation by 1.3 feet. Estimated cost: $1,935,000. Action to date: The only option discussed in the CSWMP that addressed the street flooding issues completely was Option 4. However, due to potential impacts to the homes located around the pond in the SE corner of Fairview and County Road C, staff does not feel that this option is feasible. After a 6-inch rainfall event that occurred 10/4/2005, we experienced localized flooding in a number of different areas around the City. The home at 1779 Rose Place was flooded during this extreme rain event. Due to the cost, limited benefit, and potential impacts to the properties located around the pond at Fairview and County Road C, staff does not recommend proceeding with any of the options as described in the CSWMP. In an effort to address some of the flooding concerns in this problem area, staff has been requiring redevelopment projects to reduce the volume of water that is sent to this system. This is similar to the action described in Option 3. A reduction in the peak flow from the commercial properties located in the subwatershed will alleviate the demand on the Fairview trunk sewer. Some projects that were approved this year that reduced the volume of runoff going to this system for the design events: Location Predevelopment Post Development Peak Flow Rate Peak Flow Rate (100- year event) (100- year event) Rosedale Expansion 31.07 cfs 14.87 cfs Franks Nursery Redevelopment 37.61 cfs 13.848 cfs . Area 5: Arona Pond and surrounding area. Arona pond is located within the Applewood Pointe redevelopment area. Prior to development, this pond was a landlocked basin. For years the normal water level of the pond was governed by infiltration. As the surrounding area developed, the basin became a part of the storm water system. An outlet was installed around 1979 that enabled the basin to pass runoff from extreme events. Approximatly 112 acres contribute runoff to Arona Pond. Over the years, the sandy bottom of this pond became sealed with sediment, eliminating the infiltration capacity of the basin. This resulted in localized flooding of the apartments located to the south and east of the pond. Action taken to date: In 2003 as a part of the Applewood Pointe redevelopment project we reconstructed this pond. The reconstruction project nearly doubled the capacity of the basin. Years of sediment accumulation was excavated, restoring the infiltration capacity that had been sealed. In addition, a lift station was constructed to provide a secondary outlet for extreme events. The new pond serves as a regional storm water treatment facility for the subwatershed. City of Roseville 2006 Storm Water Annual Report Page 5 of 11