Attachment 5 - Stormwater Managment Plan · 132007.12.8

Table 2: MUSIC Base and Storm Flow Concentration Parameters - Commercial

                                  Total Suspended             Total
                                                                             Total Nitrogen
                                       Solids              Phosphorous
                                                                              (Log10 mg/L)
  Land Use      Parameter           (Log10 mg/L)           (Log10 mg/L)
                                  Storm      Base        Storm     Base     Storm     Base
                                   Flow      Flow         Flow     Flow      Flow     Flow
                   Mean            2.16      0.78        -0.39     -0.60     0.37     0.32
   Ground
               Std Deviation        0.38        0.39     0.34        0.50    0.34     0.30
                   Mean             1.30        N/A      -0.89       N/A     0.37     N/A
    Roof
               Std Deviation        0.38        N/A      0.34        N/A     0.34     N/A



Table 3: MUSIC Runoff Generation Parameters

                                Parameter                    Commercial
                       Rainfall Threshold (mm)                    1
                           Soil Capacity (mm)                    18
                           Initial Storage (%)                   10
                               Field Capacity                    80
                   Infiltration Capacity Coefficient a           243
                   Infiltration Capacity Coefficient b           0.6
                           Initial Depth (mm)                    50
                           Daily Recharge (%)                     0
                           Daily Drainage (%)                    31
                     Daily Deep Seepage Rate (%)                  0


2.3.2 Catchment Areas
As the site is predominately a roofed carpark, the development site has been divided
into two source nodes representing roof and ground which contribute to the
bioretention basin. The area reporting to the bioretention basin represents all the
development site. Table 4 outlines the catchment areas and imperviousness
represented within the MUSIC model. The stormwater quality catchments are
provided in Figure 2.
Table 4: Catchment Areas

                 Catchment                      Roof        Ground          Total
                Carpark (ha)                0.158            0.044          0.202
                Impervious %                 100              30              -




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