Reference Documents - 5 School Street, Pomona - MCU24/0165 & OPW24/0222

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                 However, AO6.2 of NSC Water Quality and Drainage code indicates that all developments must achieve
                 water quality objectives and must use natural processes wherever possible. Therefore natural treatment
                 through a bio basin system has been adopted and designed in the following sections.
                 5.6.2.1 MUSIC Modelling
                 MUSIC (MUSICX by eWater), a pollutant export modelling program, has been used to model the
                 expected pollutant loads generated by each catchment within the development and the effectiveness
                 of WSUD treatment options selected.
                 5.6.2.2 Catchment Approach
                 The MUSIC model is based on a split catchment approach, modelled as various catchments
                 representing the different surface types in accordance with the guidelines and available site information.
                 Split catchment surface information was informed by taking measurements of the site layout in
                 accordance with HLW guidelines and are shown in Table 3.
                 TABLE 3: ADOPTED AREA & PERCENT IMPERVIOUS – URBAN RESIDENTIAL

                         Surface Type                Area (ha)            Percent of Site (%)       Percent Impervious
                                                                                                            (%)
                              Roof                     0.096                       51                            100
                           Driveway                    0.043                       23                             80
                             Ground                    0.049                       26                             30

                 5.6.2.3 MUSIC Meteorological Data
                 Weather data from Cooroy station 40059 was used for the MUSIC analysis. The 10-year climate period
                 was selected from 01/01/1973 to 31/12/1983 in accordance with HLW guidelines. The rainfall and
                 evapotranspiration data with a 6-minute time step, was used in the model.
                 Input parameters for the rainfall-runoff, source nodes and treatment devices were also obtained from
                 the guidelines. The following parameters were selected based on urban residential development.
                 5.6.2.4 Rainfall-Runoff Parameters
                 The rainfall-runoff parameters listed in Table 3.7 of MUSIC guidelines were used in the model. The
                 parameters recommended by the guideline are as shown in Table 4.




                  15 November 2024                                                                                         Page 12
Document Set ID: 23679130
Version: 1, Version Date: 08/04/2025