RFI - Attachment 4 - Updated Stormwater Management Plan

                                STORMWATER MANAGEMENT PLAN
Client: Devcon Capital 9                                              Location: 11 Leo Alley Road, Noosaville


catchment source node. No routing of drainage links was adopted for the purpose of taking a
conservative approach. This approach assumes that the flow through the drainage system takes no
time, which over estimates the likely pollutant load. MUSIC version 6.3.0 was used for this
assessment. Copies of the MUSIC models are found in Appendix B.

3.2.2 Scenario Method
The proposed development was modelled using split catchment source nodes, comprised of roof
area, driveway and landscaping nodes. It is considered that each catchment needs to achieve the
required pollutant reduction targets. The total area of the proposed development is approximately
0.5 ha, and consists of 21 industrial units. The development has been split into two (2) catchments
(catchment A and B). Refer to Table 3 and Figure 2 for detail.

                               Table 3 – Catchment Characteristics
                                Roof (ha)             Driveway (ha)              Landscape (ha)
  Fraction Impervious            100%                     100%                        0%
      Catchment A                0.208                    0.127                      0.014
      Catchment B                0.033                    0.053                      0.008

A portion of the landscape area within catchment A and B is proposed to bypass the bioretention
basin within each catchment respectively. Refer to Figure 2 for the MUSIC map and Appendix B for
the MUSIC model for further information.




                                   Figure 2 – MUSIC Model Map



Covey Associates Pty Ltd                          3                                    Project No: 192297
Consulting Engineers                                                                     26719Rpt, Issue E