Revised Stormwater Management Report

DocuSign Envelope ID: DB0533B0-B14B-449D-A0A8-3B9C3C0DF5D9 Porous Pavement system 11 Tc Computations System 11 collects stormwater from Road D , half of the Building D roof and adjacent gras areas The ratio of contributing areas to the Porous pavement area is 2.97 : 1 The system will have soil replacement with a permeability rate of 4 inches per hour with a factor of safety of 2. The proposed Tc for the area flowing to PP11 uses the following input Sheet flow 83 lf @ 4% over grass 8.9 minutes Shallow Concentrated Flow 150 lf @ 3.3% over grass .9 minutes Total Tc = 9.8 minutes The porous pavement system is considered green technology for both groundwater recharge and water quality. PA-2 Discharge Summary STORM WQ 2 10 100 EX PER 15.19 7.6 34.19 23.93 75.56 60.4 2 0 0 1.51 14.43 3 0 .66 2.74 6.36 4 0 0 .35 1.01 7 0 .56 2.01 4.01 10 8 0 .03 .61 2.90 9 0 0 0 .14 10 0 .65 .66 11.25 11 0 .18 2.42 7.75 UD 3.71 7.56 13.67 26.01 T 3.71 7.6 19.45 56.02