Scg 33132(L2)

We have amended our stormwater management plan to include additional storage to increase the total stored
volume to 32kl.


Issue 15 – Drainage Design
  No drainage design calculations are provided to demonstrate that the stormwater devices have been
  adequately sized to convey the critical minor and major rainfall events.

Response
Pipe long sections and HGL diagrams are provided on SCG DRG No. 33132-SW1.4 and as per the provided
SWMP the following design storms have been adopted.


    -    Minor Drainage System – 10% AEP
    -    Major Drainage System – 1% AEP.

As mentioned above, a rainfall multiplier of 1.2 has been applied to the PC DRAINS model and therefore the
provided HGL diagrams also include an increase to rainfall intensity of 20% to consider the impacts of climate
change. We confirm that both the major and minor drainage networks have been adequately designed to convey
the critical storm events mentioned above.

Issue 16 – Detention Tank and Bio-Detention Basin Details
  Several details are missing from the amended stormwater and engineering plans provided. Additional detail is
  required to address the following:




SCG Consulting Engineers                          Page 3 of 5                                 SCG Ref: 33132(L2)