Civil Response

 10 May 2022


The other lots are intended to have the following stormwater connections:

        •   Lot 1, 2, 3 – kerb adapter connections to Butler Street
        •   Lot 5 – Kerb adapter connection to Ghostgum Court

Refer to drawing DA.01 in Appendix 3 of the Stormwater Management Plan prepared by
MPN Consultants for details of the proposed stormwater connections.

Rational Method Calculations have been undertaken for the pre-development and post-
development flows to the south west of the site. The results indicate that the peak flows are
non-worsening from the pre-development scenario to the post-development scenario. Refer
Table 1 below and the attached calculations for details.

                                                              South West Catchment
                                                               Peak Flows (m3/sec)

      Average                     2                 5              10       20        50     100
    Recurrence
  Interval (Years)

     Site Pre-                0.031             0.043             0.050   0.059      0.075   0.086
   Development

    Site Post-                0.024             0.033             0.038   0.046      0.058   0.066
   Development
                                          Table 1 – Rational Method Flows

Attached for your reference are:

        •   Pre-development catchment sketch
        •   Rational method calculations



Yours faithfully




Sam Rowen
For and on behalf of
MPN CONSULTING PTY LIMITED
sr:sr




 Excellence with Economy in Engineering                                                              2
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