Att 1 - Engineering - RFI Reponse · MCU21/0117.01

                                                                                23098 - SBSMP/4
                                                                                       Page 13




                            Figure 5.3 – Post-Development Mitigated Model

5.3.7 Comparison of Peak Flows at Lawful Point of Discharge
The pre-development and post-development mitigated peak flow rates were compared for the
catchment and are shown in Table 5-6 and Table 5-7 below.

                                     Table 5-6 - Comparison of Peak Flows


                 Pre-Development Peak Flows Post-Development Peak Flows Post-Development Peak Flows
Property State          (Un-Mitigated)             (Un-Mitigated)                (Mitigated)
                            (m3/s)                     (m3/s)                      (m3/s)

   50% AEP
    (m3/s)
                            0.035                          0.055                  0.034
   20% AEP
    (m3/s)
                            0.058                          0.084                  0.048

   10% AEP
    (m3/s)
                            0.065                          0.094                  0.056

5% AEP (m3/s)               0.084                          0.110                  0.064

2% AEP (m3/s)               0.102                          0.135                  0.089

1% AEP (m3/s)               0.115                          0.155                  0.087


Site Based Stormwater Management Plan
Proposed Townhouse Development at 5 Pearl Street, Cooroy