Request to Amend Application and Response to DSDIP's Information Request · MCU14/0009

3.5 Construction Phase Stormwater Management
The management of the site during the construction phase is an important step in
ensuring water quality standards are achieved. Implementation of best practice
Erosion and Sediment Control techniques is imperative to managing the quality of
runoff affected by construction works.
The following points provide general guidance on the management of stormwater
during the construction phase. Detailed Erosion and Sediment Control Management
Plans should be developed prior to construction works commencing in accordance
with Council’s Maroon Manual - “Manual for Erosion and Sediment Control”.
   1. Establish a single stabilised entry/exit point for the site works;
   2. Construct a shake-down grid at the entrance to facilitate the removal of
      sediment from vehicles leaving the site, which should comprise a 150-200mm
      deep pad of 40mm crushed rock;
   3. Install sediment fences along the lower boundaries of the site;
   4. Install bins and/or wind-proof litter areas on-site to minimise the dispersion
      of gross pollutants;
   5. Maintain on site spare materials necessary for the emergency repair of all
      erosion control devices. This includes silt fences and clean crushed rock for
      reapplication to the entrance;
   6. Following each days construction works, ensure that any material on road
      surfaces is swept from the road, and not permitted to be washed down the
      gutters and piped drainage systems.
   7. Final establishment of bioretention basin should not occur until full
      stabilisation of upstream site has occurred; preferably these should be
      temporarily turfed while commercial construction is occurring.
It shall be the responsibility of the developer, through their principal contractor, to
ensure that temporary sediment and erosion controls are installed and maintained
correctly.
Experience shows that the critical periods in the life of WSUD vegetated stormwater
systems are the construction and establishment phases. The timing and approach to
these systems must be carefully considered to ensure successful establishment and
long-term performance. Bioretention systems are now common stormwater
treatment devices for new urban developments in South East Queensland.
Successful construction and allowing adequate time for the systems to establish is
critical to their long-term performance and function. Construction of the system is
also linked to having suitable bioretention designs in place to ensure, civil
contractors have appropriate plans to construct to. Applying due care in the design
and construction phase will ensure the function of the system whilst also keeping
on-going maintenance to a minimum. It is highly recommended that the constructed
activities be completed in accordance with the Construction and Establishment
Guidelines: Swales, Bioretention Systems and Wetlands (Apr 2010).




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