LATE RFI - SCG 33114 (SWM) Rev A

                                         Figure 6.1 – Drains Model Layout



Peak flow rates determined for each 3 cases are outlined in Table 6.6.
                                       Table 6.6 – Comparison of Peak Flows

         AEP          Q1     Q2      Q5      Q10      Q20     Q50    Q100
        Storm       (1EY) (0.5EY) (0.2EY) (10%AEP) (5%AEP) (2%AEP) (1%AEP)
       Existing       24       33            45           56            69       83            95
        (L/s)
     Developed        40       50            62           69            83      102            118
       (L/s)
      Mitigated     24 (0)   31 (-2)       45 (0)       56 (0)        69 (0)   79 (-4)       91 (-4)
       (L/s)



As shown in Table 6.6 the proposed detention tank has demonstrated the proposed mitigated peak
discharge flow rates will not exceed the total pre-development flows for all design storms, up to and
including the 1% AEP Design Storm. Refer Appendix D for the drains results.
The proposed stormwater detention system is therefore considered to be adequate for the development.


SCG Consulting Engineers                      Page 14                                 SCG Ref: 33114(SWMP)