B07056.W-01A Complete - Stormwater [As Published] · 132007.2398

Concept Stormwater Management Plan
RSL Care – Cooroy Retirement Village

6.3.2              Source Nodes

Source node land-use characteristics must be defined for MUSIC modelling purposes. The site under the
developed scenario was categorised into land-use types according to source node types in the MUSIC program.
Developed scenario sub-catchments were further apportioned into roofed and non-roofed nodes in order to
model rainwater tanks. The impervious percentage for all roofed areas was assumed to be 100%. The Gold
Coast City Council MUSIC Modelling Guidelines (2006) were referenced to configure the pollutant concentration
properties of roof areas. For non-roofed areas, percentage impervious values were determined based on
proposed road and other hard surface areas. The effective impervious factor was applied to each impervious
percentage value for the non-roofed area of each sub-catchment in accordance with Table 2.2 of Brisbane City
Council’s Pollutant Export Modelling Guidelines.

Stochastic generation estimation and serial autocorrelation set to zero has also been adopted.

The developed site sub-catchment areas and percentage impervious values are presented in Table 6.3.

    Table 6.3: Developed and Mitigated Scenarios Sub-Catchment Areas and Percentage Impervious Values
                Sub-Catchment                 Area (ha)        % Effective Imp.               Land Use
        North ILU Roofs                        0.701                 100                  *Urban Residential
        Apt 1 Roof                             0.150                 100                  *Urban Residential
        RAC Roof                               0.378                 100                  *Urban Residential
        North Catch                            1.005                  10                  Urban Residential
        North Bio Basin Catch                  1.527                  6                   Urban Residential
        North Bio Pod 1 Catch                  0.122                  20                  Urban Residential
        North Bio Pod 2 Catch                  0.168                  20                  Urban Residential
        Remainder of North Catch               2.931                  2                   Urban Residential
        Central ILU Roofs                      0.244                 100                  *Urban Residential
        South ILU Roofs                        1.303                 100                  *Urban Residential
        Apt 2 Roof                             0.140                 100                  *Urban Residential
        Village Ctr Roof                       0.082                 100                  *Urban Residential
        South Catch                            3.454                  8                   Urban Residential
        South Bio Basin Catch                  0.935                  8                   Urban Residential
        Remainder of South Catch               0.424                  1                   Urban Residential
        Entrance Rd Bypass                     0.089                 15                   Urban Residential
        TOTAL                                  13.65
                          *Denotes roof nodes with pollutant parameters applied as per GCCC (2006).

6.3.3              Drainage Links

No routing has been adopted for all drainage links within each model.

6.3.4              Treatment Nodes

Bio-filtration Basins, Bio-filtration Pods, Rainwater Tanks, Wetlands and Ponds were modelled in MUSIC. The
Bio-filtration Basin and Bio-filtration Pod treatment nodes have the following properties presented in Table 6.4.




B07056.W-01A.doc                                                                                           Page 15