2506 MELVIN AVE 2018-01-02 MF Import

� Willows Apartmrnts Drainage SNdy � 09/16/2009 SITE HYDRAULIC ANALYSIS Existing Conditions: � Total Site Development Area = 030Acres Basin(Lot Area) = 13,060 SF = 030 Acres � Existing Pervious _ 11,295 SF = 0.259 Acres ROW pervious impacted 582 SF = 0.134 Acres Existing ASPH = 0.0 SF I Roof Buildings = 1.765 SF Existing Impervious Area 1,765 SF = 0.0405 Acres L1 = 123' @ 5.70% ITc = 10/7.0 Develoned Conditions: � Proposed New RooRop = 4,142 SF Proposed Parking& D/W = 3,436 SF Proposed Imperv Sidewalk = 1,199 SF I Pmposed Perv Sidewalk = 1810 SF Total New Impervious = 10,587 SF ' Pmposed Pervious = 2,473 SF = 0.057 Acres Proposed Impervious Area = 10,587 SF = 0.243 Acres � Total Development Area = 13,060 SF = 030 Acres Net Impervious Increase = 10,587— 1,765 = 8,822 SF =0.203 AC ' ROW Detentron Correction: _ ROW lmprovement Area = 2,780 SF — 0.0638 Acres � ROW Exist Pervious Area = 1,586 SF _ 0.0364 Acres ROW Existing Paving = 1,194 SF 0.0274 Actes ( Proposed ROW Imp. Area = 1,776 SF _ 0.0394 Acres ` Proposed ROW Pervious = 1,074 SF 0.0244 Acres New ROW Impervious = 582SF = 0.0134 Acres• � (*To be added to Developed Impervious for Detention Requirement) We'll correct our detention volume for the amount of new pavement surfaces To be created in the Melvin Avenue ROW. This will make the developed basin �, Slightly lazger than the property but will address the project impacts. Undeveloped Pervious= 0.259 +0.0134= 0.2724 Acres t. Undeveloped Impervious= 0.0405 Acres � Developed Pervious = 0.057 Acres Developed Impervious= 0.243 +0.0134 �.256 Acres � 4 eaoJecr:osei2 1