Response to Info Request - Attachment 4a - Engineering Report Part 1 MCU18-0015 & RAL18-0001 · MCU18/0015

A conceptual layout of the treatment train as input to the MUSIC Model is shown in Figure
7.3.1a below.




                           Figure 7.3.1a: MUSIC Model Layout


The locations and details of the water quality treatment devices are shown on Engineering
Drawings C5756/18/P33, attached as Appendix C.


The Rainfall Runoff Parameters for the source catchments have been taken from Water
By Design’s – MUSIC Modelling Guidelines, Version 1.0 2010 and are shown in Table 7.3.1b
below.


                         Table 7.3-1b: Rainfall Runoff Parameters
           Rainfall Threshold mm/day                                       1
                                Pervious Area Properties
            Soil Storage Capacity (mm)                                  500
            Initial Storage (% of Capacity)                              10
            Field Capacity (mm)                                         200
            Infiltration Capacity Coefficient - a                       211
            Infiltration Capacity Exponent - b                           5.0
                                Groundwater Properties
            Initial Depth (mm)                                          50
            Daily Recharge Rate (%)                                    28.0
            Daily Baseflow (%)                                         27.0
            Daily Deep Seepage Rate (%)                                 0.0

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