8. APP G. Engineering RFI Response

          STORMWATER QUALITY
          EXISTING WATER QUALITY
          No stormwater quality control measures have been incorporated into the existing site drainage
          infrastructure.


          WATER QUALITY ENVIRONMENTAL VALUES
          AND WATER QUALITY OBJECTIVES (WQO)
          The subject site is located within the region of South East Queensland and as such the
          Department of Environment and Heritage Protection has specified Environmental Values and
          Water Quality Objectives for the management of stormwater quality in this region under
          Schedule 1 of the Environmental Protection (Water) Policy 2009. This document stipulates that
          stormwater design objectives for industrial developments are to be as per the ‘Urban
          Stormwater Quality Planning Guidelines 2010.’ This document provides specified design
          objectives for both the construction and operational phases of the development in accordance
          with landscape features and the regional location of the proposed development.

          As per the ‘Urban Stormwater Quality Planning Guidelines 2010’, the identified Water Quality
          Objectives for South East Queensland are defined as:

          Table 6.1: Design Objectives for Management of Stormwater Quality in South East Queensland
          – Operational (Post-Construction) Phase of Development
           Pollutant                          Minimum reductions in mean annual loads from
                                              unmitigated development (%)

           Total Suspended Solids (TSS)                                              80

           Total Phosphorus (TP)                                                     60

           Total Nitrogen (TN)                                                       45

           Gross Pollutants > 5mm                                                    90




          PROPOSED STORMWATER IMPROVEMENT
          DEVICES
          Water Sensitive Urban Design (WSUD) aims to minimise the impact of a development on the
          natural water cycle by reducing the export of pollutants, sediments and nutrients from the site
          into the natural watercourse. In order to treat the stormwater runoff from the site, various
          treatment devices can be used throughout the development area and these concepts can be
          integrated into the overall design of the road layouts, road cross sections, stormwater layouts
          and water supply reticulation systems. Stormwater from the development will follow a specially
          designed stormwater quality treatment train prior to discharge from the site, which will ensure
          compliance with the water quality objectives.




                                                                                          Stormwater Management Plans
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