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The following table summarizes the areas input into the WWMH software for the drainage <br /> analysis of the predeveloped and developed on-site basins for each threshold discharge <br /> area. <br /> Basin A <br /> Existing Site <br /> Predeveloped Area: 0.02 ac (disturbed area only) <br /> Hydrologic Soils Group C (Till) <br /> Impervious Area: 0.00 ac <br /> Pervious Area: 0.02 ac (Forest, Type C Soils, Moderate Slope) <br /> Existing Condition Event Output:WWHM12 <br /> Peak Flow(cfs) Area (ac) <br /> 2-yr 0.000 0.02 <br /> 10-yr <br /> 0.001 0.02 <br /> '50-yr 0.001 0.02 <br /> 100-yr <br /> 0.001 0.02 <br /> Developed Site <br /> Developed Area: 0.02 ac <br /> Hydrologic Soils Group C (Till) <br /> Impervious Area: 0.02 ac(Sidewalks, Mod) <br /> Pervious Area 0.00 ac <br /> Developed Condition Event Output: WWHM12 <br /> Peak Flow (cfs) Area (ac) <br /> 2-yr 0.010 0.02 <br /> 10-yr 0.01-7 0.02 <br /> 0.02 <br /> 0.023 <br /> 50-yr 100-yr 0.026 0.02 <br /> The output from the WWHM for the 100-year flow frequency for the existing and <br /> developed basins area as follows: <br /> Peak'100-year'flow rate for Existing Condition: 0.001 cfs <br /> Peak 100-year flow rate for Developed Condition: 0.026 cfs <br /> Change in 100-year flow rate: 0.025 cfs <br /> SeahuratSP 18-0727 <br /> September 2019 Page 13 <br />