16-001014-02A (Ultimate SCMMP)

 Design Feature                                              WQCP Details
 Gross pollutant control is provided at the outlets in the   As per Drawing No. 16-001014-400 Series in Appendix D,
 WQCP to ensure human derived litter does not                the proposed GPTs and Bioretention Devices provided
 provide breeding habitats for mosquitoes.                   upstream of the ponds will capture gross pollutants, such as
                                                             human derived litter, prior to discharge into the pond.
 Access to the WQCP is provided to allow for field           Maintenance access tracks have been designed for ready
 operators to monitor and treat mosquito larvae.             access into the WQCP.

While these features have been implemented in the design of the WQCP, regular monitoring of mosquito activity during
construction and operational phases is necessary to allow for the changes in climatic and vegetation conditions.

2.1.3     CYANOBACTERIAL BLOOMS

The approved Letter Report (No. B14158.W.07L dated 8 October 2015), outlines the WQCP design requirements for
managing cyanobacterial blooms. These have been implemented in the design as per Table 2-2 below:
Table 2-2: Design Features for Managing Cyanobacterial Blooms
 Design Feature                                              WQCP Details
 Maximum hydraulic residence time (HRT) of 15 days           A HRT of twelve to fourteen days has been calculated for the
 for all constructed WQCPs, ponds and basins.                WQCP, based on inputs from the design. This is below the
                                                             desired maximum HRT of 15 days (refer to Section 4.4.5.2 of
                                                             the SWMP Report (No. 16-001014-01A dated September
                                                             2016).
 Minimising the nutrient load reaching the open water        A treatment train involving GPTs and Bioretention Devices
 body by provided a treatment train that pre-treat all       upstream of the proposed pond has been provided to pre-
 flows from hardstand areas and most landscape               treat runoff from the development.
 areas prior to the downstream water body.

 The median concentration of Total Nitrogen and Total        A MUSIC model has been configured to determine pollutant
 Phosphorous for stormwater inflows to downstream            removal from the Bioretention Devices located upstream of
 waterbodies is less than 1.3mg/L and 0.2mg/L                the proposed Central WQCP. Daily results indicate a median
 respectively.                                               concentration of 0.6mg/L for Total Nitrogen and 0.02mg/L for
                                                             Total Phosphorus entering the WQCP, which meets the
                                                             required objectives. Results from the MUSIC modelling are
                                                             provided in Appendix A.
 All open water zones are less than 3m deep.                 The lowest level of the deep water zones is 97.2m AHD with
                                                             a Normal Operating Level (NOL) of 99.2m AHD. Based on
                                                             this the open water zone is 2m, which is less than 3m.
 Macrophytes are more than 20% of the WQCP water             As per Drawing No. 16-001014-400 Series in Appendix D
 surface;                                                    the Macrophyte area covers 540m2 of the WQCP water
                                                             surface, which is 27% of the NOL pond area (1,990m2).
 Macrophytes are to be composed of a minimum of              Refer to the Landscaping Architectural plans for
 three species                                               specifications of macrophyte vegetation species.
 Landscaping and management will be designed to              Refer to the Landscaping Architectural plans for planting
 avoid the need for fertilisation.                           specifications.




16-001014-02A | SMCMP | PALM LAKE RESORTS                             COOROY RETIREMENT COMMUNITY, TRADING POST
                                                                                                  ROAD, COOROY              |4