Attachment 4 - Stormwater Management Plan by O2 · MCU13/0251

3.            Construction Phase Stormwater Quality Management
Management of stormwater during the construction phase is to be undertaken in accordance with the site
specific Erosion and Sediment Control Plan and other management plans provided by the Supervising
Engineers or Civil Contractors.

Construction and establishment of the proposed bioretention basin should be undertaken in accordance
with Council guidelines and conditions and the approved engineering and landscape plans. The Water by
Design ‘Construction and Establishment Guidelines – Swales, Bioretention Systems and Wetlands, 2009’ are
an advantageous guide to utilise during the construction and establishment phase of the bioretention
systems.

A major risk for establishing functioning bio-retention systems is the inflow of sediment-laden runoff during
the construction and building phases. Captured sediment can potentially clog the filter media minimizing
the overall effectiveness of the constructed treatment system.

Managing sediment during the construction and building phases is critical for the establishment of the bio-
retention system and in reducing the risk and costs associated with reconstructing the system. The typical
phases associated in the creation of a development site are detailed below in Figure 4.




Figure 4– Typical phases in the creation of a development site(Source: Water by Design, 2009)

To overcome challenges associated with delivering bio-retention systems, one of the following four options
for construction and establishment are recommended:

         Option 1: Surface Protection;
         Option 2: Bypass flows and early establishment of vegetation;
         Option 3: Sediment basin and bio-retention function; and
         Option 4: Leave as sediment basin.

Further information on each option is provided in the Water by design‘Construction and Establishment
Guidelines – Swales, Bioretention Systems and Wetlands, 2009’. More details in relation to the construction
of the bioretention systems will be provided prior to Operational Works Approval.




STORMWATER MANAGEMENT PLAN – PEREGIAN VILLAGE MARKET                                                   Page 4

Scanlon Property Group
R002616