Appendix I - Stormwater Management Plan

                 B for further information on cleaning and maintenance of the detention/filtration
                 system.


        3.5.2 Gross Pollutant Traps

                 All field inlet pits are proposed to contain gross pollutant traps/filter bags (EnviroPod
                 200 or similar) prior to discharging to the stormwater quality device as discussed in
                 Section 3.5.1.
                 Refer to product brochures in Appendix B.
                 Based on the manufacturer’s advice, it has been estimated that the average cleanout
                 frequency is approximately once annually.
                 Clear and unobstructed access to the GPT’s will be required in order to regularly
                 clean and maintain the devices. GPT’s have been located within the proposed
                 driveway and as such are accessible by vehicles for servicing. The current proposal
                 shows nominal locations to demonstrate appropriate access for maintenance. Refer
                 to product brochures in Appendix B for further information on cleaning and
                 maintenance of the gross pollutant traps.


        3.5.3 Calculations

                 Reference is made to the attached drawing no. 205-002-C13.01 (Appendix D) which
                 details the development site catchment area requiring treatment by the system, post
                 development.
                 The treatment train which incorporates a stormwater detention/filtration system and a
                 gross pollutant trap was completed using the Model for Urban Stormwater
                 Improvements Conceptualisation (MUSIC) software to estimate system performance
                 against the water quality objectives.
                 The treatment train effectiveness (refer to Figure 3.4 overleaf) shows the total
                 suspended solids (TSS), total phosphorus (TP) and total nitrogen (TN) load removal
                 performance for the treatment train which demonstrates achievement of the water
                 quality targets detailed in Section 2.4 – Water Quality Objectives.
                 Figure 3.2 provides the layout of the source and treatment nodes used in the water
                 quality modelling.




Mogpropmanagement Pty Ltd                          Page 7                                    205-002-002R
Stormwater Management Plan
Noosaville Site