Reference Document - Site Based Stormwater Management Plan · MCU21/0117.01

                                                                                         23098 - SBSMP/4
                                                                                                  Page 17




6.3 Operational Phase
Water quality objectives (WQO’s) for South East Queensland as set out in State Planning Policy 2017
(SPP 2017) should be achieved by identifying and adopting best practise techniques in accordance
with the abovementioned guidelines. Refer to Table 6-3 for the target WQO’s.

                           Table 6-3 – Minimum Mean Annual Load Reductions

                                                             Minimum Mean Annual
                                    Contaminant
                                                                Load Reductions

                            Total Suspended Solids (TSS)            ≥ 80%
                               Total Phosphorus (TP)                ≥ 60%
                                Total Nitrogen (TN)                 ≥ 45%
                               Gross Pollutants (GP)                ≥ 90%

6.3.1 Sources of Contaminants
Potential sources of contaminants and stormwater quality improvement devices identified for the
operational phase of the development are outlined in Table 6-4.

                                   Table 6-4 - Sources of Contaminants

                                                 Pollutant
               Target Pollutant Type                             Acceptable Treatment Examples
                                                   Size

         Primary        Screening of gross                     Litter baskets, swales, buffer strips,
                                                 >5000um
        Pollutants          pollutants                            GPT’s, underground detention

                        Sedimentation of
        Secondary                                125um -
                        coarse to medium                       Swales, sedimentation basins, ponds
        Pollutants                               5000um
                            sediment
                                                               Underground detention, constructed
                           Enhanced
                                                  10um –      wetland macrophyte zones, other bio
                      sedimentation of fine
                                                  125um          technologies, proprietary tertiary
                          particulates
                                                                   stormwater treatment dvices
         Tertiary     Adhesion and filtration                Constructed wetland macrophyte zones,
                                                 0.45um –
        Pollutants    of very fine / colloidal                  other bio technologies, proprietary
                                                   10um
                             sediment                         tertiary stormwater treatment dvices
                       Biological uptake of                  Constructed wetland macrophyte zones,
                                                 <0.45um
                        dissolved particles                          other bio technologies




Site Based Stormwater Management Plan
Proposed Townhouse Development at 5 Pearl Street, Cooroy