RFI - Attachment H - Stormwater Management Plan_Issue C_

15 May 2019


The pollutants that could be potentially generated as a result of the development use are as follows:

          Litter
          Sediment
          Nutrients (Nitrogen and Phosphorous)
          Hydrocarbons (oils and grease)
          Surfactants
          Pathogens/Faecal Coliforms (bacteria and viruses)

The MUSIC computer modelling program developed by the Co-operative Research Centre for
Catchment Hydrology was used to predict the performance of the proposed stormwater treatment
train.

At this stage the pollutants modelled in MUSIC are Total Suspended Solids (TSS), Total Phosphorous
(TP) and Total Nitrogen (TN).

5.3.3.2 Rainfall
The rainfall data used in the model was based on the Bureau of Meteorology data from rainfall station
40059 Cooroy Composite. The model was run for a 10-year period from 1 January 1973 to 31
December 1983. The modelling time step was 6 minutes.

5.3.3.3 Rainfall Runoff Properties
In accordance with the recommendations of Water By Design’s MUSIC Modelling Guidelines for South
East Queensland rainfall runoff properties for commercial areas have been used.

These are listed in Table 2 below.
.
Parameter                                                                              Value


Rainfall Threshold (mm)                                                                 1

Soil Storage Capacity (mm)                                                              18

Initial Storage (% of capacity)                                                         10

Field Capacity (mm)                                                                     80

Infiltration Capacity Co-efficient a                                                   243

Infiltration Capacity Co-efficient b                                                    0.6

Initial Depth (mm)                                                                      50

Daily Recharge Rate (%)                                                                 0

Daily Base Flow Rate (%)                                                                31

Deep Seepage (%)                                                                        0
                             Table 2 – MUSIC Rainfall Runoff Parameters (Commercial)

5.3.3.4 Pollutant Export Parameters



Excellence with Economy in Engineering                                                                  11
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