2160 IWMP Report_Jan2022

                                                                               Callaghan & Toth

4.2.3 Rainfall Data

The meteorological data used for the MUSIC Model was the data for Cooroy from 01/01/1973 –
31/12/1983, as outlined in the MUSIC Modelling Guidelines for South East Queensland –
Version 1 December 2010.

The mean Annual Rainfall for Cooroy Composite                  1973 – 83 = 1600mm


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 6.3.0 is 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 Water by Design Deemed to
Comply Solutions – Stormwater Quality Management (South East Queensland) version 1.0 –
Table A-2 (2010). The following have been included in Appendix 2:
                The treatment train effectiveness for the system.
                The MUSIC Version 6.3.0 Summary Report.
The information above indicates that the additions to the NoosaCare Kabara site and 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
                                           REDUCTION                LOAD
                                            RESULT               REDUCTION
                                                                  TARGETS
              Flow                             12.5%
              Total Suspended Solids            85%                  80%
              Total Phosphorous                 59%                  60%
              Total Nitrogen                    65%                  45%
              Gross Pollutants                 100%

4.3.2 Assessment of Results
The developed site has been modelled as a series of commercial sub-catchments, which
incorporate Water Sensitive Urban Design (WSUD) treatment trains. Plan No’s 2160-01 to 03
shows the proposed locations of the rainwater tank, bio-retention swale and bio-retention basin.
The reductions listed in Section 4.3.1 above comply with Council’s requirements. Therefore, it is
considered that the proposed stormwater treatment system is currently sufficient to reduce the
pollutants prior to exiting the site. The 59% reduction of Total Phosphorus from the proposed
system is just below the target of 60%, which is considered within an acceptable error range.


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2160, Kabara Upgrade, Cooroy               IWMP.doc                          January 2022