1714 IWMP_Report_Carramar_Version2 Oct 2018

                                                                                         Callaghan & Toth


4.2.3 Rainfall Data

The meteorological data used for the MUSIC Model was the data for Cooroy from 01/01/73 –
31/12/82.

The mean Annual Rainfall for Cooroy                             1973 – 1982 = 1600mm


The MUSIC Modelling Guidelines for South East Queensland – Version 1 December 2010
details that Cooroy data for 1973 to 1983 should be used.

4.3      MUSIC Modelling Results

The MUSIC modelling program has been used to investigate the performance of various
treatment options in the treatment train. MUSIC version 6.2.1 is the current version and capable
of incorporating rainwater re-use in the model. These features have been used in making
comparisons between different stormwater management systems for this report.


4.3.1 Water Quality Objectives

This model meets the pollution load reduction target as detailed in the State Planning Policy
2017 (Appendix 2: Table B). The following have been included in Appendix B.

         •       The treatment train effectiveness for the system.
         •       The MUSIC Version 6.2.1 Summary Report.

The information above indicates that the new Villas, entry building and associated carpark and
landscaping with the proposed stormwater treatment train will achieve reductions in pollutant
loads as detailed in Table 4.2 below.

         TABLE 4.2:          COMPARISON OF LOAD REDUCTIONS

              Parameter                                 MUSIC        POLLUTANT LOAD
                                                      REDUCTION         REDUCTION
                                                       RESULT            TARGETS
                                                                     (Source: SPP 2017)
              Flow                                      17.7%
              Total Suspended Solids                    80.6%               80%
              Total Phosphorous                         60.8%               60%
              Total Nitrogen                            54.8%               45%
              Gross Pollutants >5mm                     100%                90%




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1714-Cartwrigth Village Extension_IWMP_Version2.doc                                    October 2018