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a stormwater to not allowed as a be reevaluated. The stage storage data for the proposed detention basin to be located on the Armory site is provided in Table 2: Ta e . ta2e- torage ata or Propose on Elevation Area Volume Total Storage Type (ft) (sa. ft.) (cu. ft.) 886 736 0 887 1,240 988 Dead Storage 888 2,247 1,744 Dead Storage 889 3,642 2,945 10,191 sq. ft. = f--- 890 5,386 4,514 0.234 ac- ft 891 7,672 6,529 Live Storage 892 11,582 9,629 Live Storage 893 14,802 13,194 45,528 sq. ft. = 894 17,550 16,176 1.05 ac-ft bl 2 S s D fi dP d HydroCAD, a computed aided surface-water modeling tool was used to simulate the flow rates for the existing and proposed conditions, based on the total developable area. The proposed conditions model incorporates the Live Storage portion of the proposed pond data in Table 2. The following parameters and assumptions were used in the HydroCAD models: . The SCS TR-20 hydro graph method was chosen. . The curve number (CN) values used in the HydroCAD models were 98 and 68 for impervious and pervious areas, respectively. The existing conditions model included the house, garage, and driveway for a total impervious area of 4,727 sq. ft. The proposed conditions model included the 11,000 sq. ft. and 25,000 sq. ft. impervious areas calculated for the Elmer Street Parcels and Guptil Parcel, respectively. . Rainfalls assumed were 2.8 inches, 3.6 inches, 4.2 inches, and 5.9 inches for the 2-,5-, 10-, and 100-yr, 24-m storm events, respectively. . The time of concentration (TC) used were 12 minutes for the existing conditions and 10 minutes for proposed conditions . A pond outlet was modeled to produce a discharge of approximately 2 cfs, as was found in the City of Roseville's Surface Water Management Plan for the existing pond. An outlet elevation of 888 feet was assumed. . No infiltration is included in the modeling