RFI - Attachment 7 - Updated SWMP

3. Stormwater Quality
3.1.        Design Objectives
This report identifies the stormwater quality management objectives for the operational phase (post-
construction phase) of the proposed development. Construction based stormwater quality management
objectives will need to be addressed as part of operational works documentation.

Section 9.4.8 of the Noosa Shire Planning Scheme (P06) defines the post-construction phase Water Quality
Objectives are to be based on the load-based Water Quality Objectives (WQO’s) and are summarised in
Table 3-1.

Table 3-1: Site Stormwater Quality and protection of receiving waters (Operational Phase)
              Minimum reductions in mean annual loads from unmitigated development (%)

       Total Suspended               Total Phosphorous                   Total Nitrogen     Gross pollutants
         Solids (TSS)                       (TP)                              (TN)              >5 mm

               80                               60                               45               90




3.2.        Stormwater Quality Treatment
3.2.1.      Strategy
The objective of this report is to assess the stormwater quality measures required based on the layout
provided and ensure adherence to the respective codes. Therefore, the following strategy has been
implemented;

     a)   Stormwater from the resurfaced carpark (catchment C) is to be collected via the stormwater
          drainage network and discharged to the Bio-retention basin (55m2) located south of the site.
     b)   Stormwater from the renovated courtyard (catchment B) is to be treated at the Bio-retention basin
          (55m2).
     c)   Half of the roof water will be directed to the rain gardens 10m 2 to the south and the rest directed
          to the 15kL rainwater tank to be utilized for internal use (flushing within the New Arts Building and
          irrigating the natural turf (renovated courtyard).

Figure 3-1 provides a summary of the strategy.




21-0211SMP01V1 | Stormwater Management Plan | Good Shepherd Lutheran College Arts Centre                 Page 8