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Future Business Park <br />6/26/2015 <br />Page 2 <br />the areas upstream of Armstrong Blvd. <br />It is our understanding that a storm sewer system installed in Bunker Lake Boulevard to manage the <br />stormwater runoff within the right of way. <br />The City's regional hydrology and hydraulics model for the WMISS watershed was utilized to develop <br />the existing peak flow rates into the COR area. Table 1 summarizes the peak inflow for a variety of <br />rainfall return intervals. <br />Table 1: Summary of Peak Flow Under Armstrong Blvd. <br />Rainfall <br />Event <br />Rainfall <br />Depth <br />Peak Flow <br />Through <br />Armstrong <br />Blvd. <br />(in) <br />(crfs) <br />2 -Year <br />2.86 <br />10.1 <br />10 -Year <br />4.26 <br />19.1 <br />100 -Year <br />7.1 <br />22.1 <br />Proposed Conditions <br />The study area can was delineated three main areas based on land use as defined in Figure 1. These areas <br />are further described below. <br />Potential regional pond locations were identified (Figure 1). Initially, ponds are assumed to be wet basins <br />with dead storage sized equal to the runoff volume from a 2.5" rainfall event per LRRWMO. Therefore, <br />volume reduction and water quality would be accommodated on site by the developer. These parameters <br />may be changed as final land uses are established and as stormwater management goals are confirmed. <br />For example: <br />• The basins could be converted to dry ponds and accommodate volume control. <br />• Ground water elevations should be confirmed to ensure that 3' separation from the water table <br />can be achieved. <br />• The basins may be used as regional rate control, water quality, and volume reduction thereby <br />eliminating the need for additional stormwater management on site. <br />Area 1: Public/Quasi-Public Area <br />This area is defined as Public/Quasi-Public. Currently, the site has been proposed to house the <br />Legacy Christian Academy campus. However, development may change. Therefore we have <br />determined the total inflow and approximate sizing requirements per Lower Rum River WMO <br />(LRRWMO) for each assumed rate of impervious area construction including the school site, single <br />family residential, and employment district. Table 2 summarizes required dead storage and volume <br />reduction for each land use option based on LRRWMO requirements. <br />Suggested areas for ponding include the northwest corner of the site, and the existing pond on the <br />