Response to Information Request - Received on 19/04/2012 · OPW11/0335

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          Southern Section


          1)    As per stage 1, without the swale for the capture of sheet-flow from the northern
                catchment areas


6.3        Modelling of the Stormwater Treatment Train

          Version 4 of the Model for Urban Stormwater Improvement Conceptualisation (MUSIC
          v4) has been utilised to predict the performance of the proposed stormwater treatment
          train. The use of Version 4 of the MUSIC model has been maintained due to the timing
          of the submission of the original application (prior to the release of Music V5). Modelling
          for both Stage 1 only and the complete development has been conducted to ensure that
          the proposed treatment system will be effective at all stages.


          Music model parameters have been developed and agreed to by the stormwater experts
          (David Bristow and Neil Collins) as part of the Planning and Environment court appeal
          (Appeal No: 2587 of 2008) concerning the development.

          In addition to load reduction         predictions a ’no worsening’ case has been applied,
          comparing        the   predicted discharge from the undeveloped site with the development
          stages.

           6.3.1      Existing Development                                ’~----."’~



          The site is presently developed as a caravan~park (the Peregian Beach Caravan Park),
          with approximately two thirds of, the existing site                             "Qeing
                                                                      cleared for caravans and
          camping, consisting of mown grass, urder a light canopy of Broad-leaved Paperbark
          (Me/aleuca quinquenerva).                                        ,




          Land uses in the Peregian Beach Village area surrounding the proposed development
          site includes retail and businesses,       facilities, a kindergarten, and the Noosa
                                                                     ~portiljlg
          National Park.                                              I




          There is currently no stormwater qualityl’improvement’ or treatment devices installed at
          the existing caravan park. Modelling has been conducted to provide a baseline to allow
          the comparison of the performance on                             aevelop {’"stormwater system to the existing
          case.     The stormwater system must achieve both the quality objectives in Table 3-1 and
          a ’no   worsening’ of pollutant loads on the national park.

          Table 6-2: MUSIC Model Results                         -
                                                                     Undeveloped Site
                            Water Quality Indicator                                                       Result

            Estimated long-term load (kg/year)                                           % reduction             Load (kg/year)

            Suspended Solids                                                                    0                      2170

           Total Phosphorus                                                                     0                          5.1

           Total Nitrogen                                                                       0                          30


           6.3.2      Stage 1 Modelling

          Results of MUSIC modelling showed that there will be no net increase in stormwater
                              Loads of sediment, total nitrogen and total phosphorus will be
          runoff from the site.
          substantially removed              from          stormwater          before   entering    the   Noosa      National         Park

          (Appendix B).




@2012 Simmonds & Bristow Pty LId                             Contrast Constructions                         J-1 005-31 0   -   22 March 2012
1:ICLlENTFILESIContrast Constructionsl1108-155c   -
                                                      Essence of Peregian SCEP Stage 1 Updatel09_Output DocumentsI1108-155C_SWMP
SCEMP_Scanlon Property Group_V4 O_ta_120321 ,doc                                                                               Page 11 of 24