Sealed Judgement

      This was modelled by including a tank to collect runoff from the cabins and then adding the
      resultant discharge at the combined outlet of the model (i.e., the discharge was not routed
      through Sub-Catchment A or A1).

x     Roof Area of Cabin 1, Carpark and associated areas

      The roof area of Cabin 1, the carpark and a portion of the suspended walkway will drain to a
      tank to be located beneath the carpark (but above existing ground level). The outflow from the
      underground tank is drains to the proposed bio-retention basin to allow for the treatment of
      runoff.

      The tank was modelled by the inclusion of a tank at the downstream end of the contributing
      catchment (A1_Carpark), with the resultant discharge added at the combined outlet of the model
      (i.e., the discharge was not routed through Sub-Catchment A).

x     Roof Areas within Sub-catchment A (i.e., Cabins 2/3, 8/9, 10/11, 12/13 and 14/15)

      Each of the roof areas of Cabins 2/3, 8/9, 10/11, 12/13 and 14/15 drain to a 3.0 kL rainwater
      tank (i.e., a combined tank capacity of 5x3kL =15kL). The tank nominally drains via a pipe to
      the proposed bioretention basin, with overflows allowed to flow to the ground as no further
      detention is required.

x     Ground Areas

      The ground areas suspended walkways were modelled as draining to the outlet of the model (as
      Sub-catchments A and A1).

Table 3-5       Post-Development Split Catchment Properties

    Catchment       Area    Impervious                             Remark
                    (ha)      Value
                                (%)

    A1_roof         0.034       100        Drains to a 6 kL rainwater tank (i.e., 2x3kL tanks).

    A_roof          0.080       100        Drains to a 15 kL rainwater tank (i.e., 5x3kL tanks).

    A_Carpark       0.089        78        Includes roof area of Cabin 1, some ground and
                                           walkways and drains to a 60m3 underground detention
                                           tank.

    A_Ground        0.174        20        Includes suspended walkways and drains to a
                                           bioretention basin.

    A1_Ground       0.077       0.0        Drains to the west into Weyba Creek drainage reserve
                                           without a detention basin.




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