RFI - 20210153 Maple St SWMP

                                   Figure 4.2 - Rainfall run-off parameters for SEQ

As the existing site is largely unchanged, only the proposed additions to the site have been
modelled The source nodes have been created using a split catchment approach with the
proposed new roof and driveway areas separated and modelled with stochastic pollutant
generation for each of the surface types as per Table 4.1 - Residential Split Node Pollutant
Generation Parameters. The area and impervious fractions for each catchment are actual values
based on the design plans.


                       Table 4.1 - Residential Split Node Pollutant Generation Parameters

  Flow Type         Surface        TSS LOG¹º                       TP LOG¹º VALUES            TN LOG¹º VALUES
                    Type           Mean      St. Dev               Mean      St. Dev          Mean      St. Dev
  Baseflow          Roof             N/A        N/A                   N/A       N/A             N/A        N/A
                    Driveway         1.00       0.34                 -0.97      0.31            0.20       0.20
                    Ground           1.00       0.34                 -0.97      0.31            0.20       0.20
  Stormflow         Roof             1.30       0.39                 -0.89      0.31            0.26       0.23
                    Driveway         2.43       0.39                 -0.30      0.31            0.26       0.23
                    Ground           2.18       0.39                 -0.47      0.31            0.26       0.23

The proposed treatment train has been modelled as shown in Figure 4.3 - MUSIC Stormwater
Treatment Train. The details of the treatments are described in the following sections




Project number 20210153
File RECOR Preliminary Stormwater Management Report - 20210153.docx, 2022-03-31                                 Page 17 of 27
Revision 1

P +61 7 5211 1003                A 75 Noosa Drive, Noosa Heads Qld 4567           E [email protected]   recorconsulting.com