PR-102995-10 IRR to Council_FINAL_27May14

            Proposed Lot 103 Detention Volume Calculation (Future)

Initial Sizing of a Detention Basin (QUDM Section 5.05.1)

                                                (QUDM EQN 5.04)

                                                (QUDM EQN 5.05)

                                                (QUDM EQN 4.13)

                                                (QUDM EQN 4.02)

                Pre-developed Flow, Qo

      Time of Concentration, t c =         10 mins
     Coefficient of Discharge, C =         0.7           (QUDM Tb 4.05.3)
                  Intensity, 10I10 =   173.22 mm/hr      (IFD Data)
                         Area, A =      0.407 ha

                                                 3
                               Qo =     0.137 m /s       (QUDM EQN 4.02)

                Post-developed Flow, Qi

      Time of Concentration, t c =          6 mins
     Coefficient of Discharge, C =       0.88            (QUDM Tb 4.05.3)
                   Intensity, 6I10 =   210.04 mm/hr      (IFD Data)
                         Area, A =      0.407 ha

                                                 3
                                Qi =    0.209 m /s       (QUDM EQN 4.02)

                                 r=     0.344            (QUDM EQN 5.05)

                                Vi =   100.38            (QUDM EQN 4.13)

                            Vs/Vi =     0.269            (QUDM EQN 5.04)

                                                  3
                               Vs =      27.0 m