Laserfiche WebLink
Existing Site Hydrology <br /> Total Site Area: 0.92 ac <br /> Hydrologic Soils Group: C (Till) <br /> Pervious Area 0.92 ac (lawn) <br /> Existing Condition Event Output: WWMH3 <br /> Peak Flow (cfs) Area (ac) <br /> 2-yr current 0.0777 0.92 <br /> 10-yr current 0.219 0.92 <br /> 25-yr current 0.327 0.92 <br /> 100-yr current 0.543 0.92 <br /> Developed Site Hydrology <br /> Basin to Detention Pipe <br /> Developed Area: 0.92 ac <br /> Hydrologic Soils Group: C (Till) <br /> Impervious Area: 0.45 ac (roof/driveway) <br /> Pervious Area 0.47 ac (landscaping) <br /> Developed Condition Event Output: WWHM3 <br /> Peak Flow (cfs) Area (ac) <br /> 2-yr mitigated 0.132 0.92 <br /> 10-yr mitigated 0.218 0.92 <br /> 25-yr mitigated 0.273 0.92 <br /> 100-yr mitigated 0.370 0.92 <br /> As shown in the tables above, this project proposes a net decrease in site runoff in the 10 <br /> through 100-year storm events. In addition, the 2012WWHM printout shows stormwater <br /> discharges match developed discharge durations to existing site durations for the range of <br /> existing discharge rates from the 10-year peak flow through the full 100-year peak flow <br /> (see Appendix A for full model printout). Therefore, the flow control performance standard <br /> and all requirements listed in section 6-10.1 of the COE DCSS have been met. <br /> Legion Lots 6&7 20-0212 <br /> April 2020 <br /> Revised:April 2021 Page 10 <br />