Noosa Springs SMP_Rev 4 · OPW17/0612

ALTUM CONSTRUCTIONS
PRECINCT F & E2 NOOSA SPRINGS DEVELOPMENT




6.        CONCLUSION
          The SQMP for the development application for Lot 7 Resort Drive, Noosa Heads
          (132005.1133.4) – Precinct F and Lot 6 Resort Drive - Precinct E2 has been developed to
          achieve the required stormwater management objectives as outlined in condition 49 of the
          decision notice issued by Noosa Council in March 2016. The key objectives of this SQMP
          included:

             Water quality modelling to develop a stormwater quality treatment train to demonstrate
              compliance with condition 49 of the Noosa Springs decision notice.

          Key design outcomes of the stormwater quality management are as follows:

             Flows will enter a series of bioretention basins and infiltration swales located within the
              proposed development. Flows will enter the treatment devices by the underground
              drainage network and overland flow paths.

             Three (3) bioretention basins will be required with a combined filter area of 182 m2.

             Three (3) infiltration swales will be incorporated with a combined filter area of 367 m2.

             For flows entering the Noosa Springs Lake System (Conditions 49 Part 1a), the
              concentration of pollutants in stormwater runoff discharged from the development site
              is less than the existing concentration at the discharge point (W5).

             For flows bypassing the Noosa Springs Lake System (Conditions 49 Part 2b), the
              percentage reduction of pollutants in infiltrated runoff cannot be quantified due to the
              limitations of the MUSIC modelling software. Therefore it is not possible to prove
              compliance with Part 2b of Condition 49.

             There will be no material impact on the residence times of the Noosa Springs Lake
              System as it was designed for a developed (50% impervious) catchment which
              includes the Site (Refer to Noosa Springs Master Drainage Plan).

          The proposed water quality treatment train outlined within this SQMP achieves most of the
          requirements of Condition 49 in the Noosa Springs Decision Notice (Precinct F); however
          as it is stated above it is not possible to prove compliance with Part 2b of the condition, for
          infiltrated flows bypassing the lakes system, due to the limitations of the MUSIC modelling
          software. However there is reasonable evidence to support the conclusion stormwater
          discharged from site via infiltration to below ground aquifers will be sufficiently treated
          prior to interacting with Lake Weyba.

          This stormwater quality management approach satisfies the treatment requirements for
          Precinct F and E2. The proposed strategy will improve the water quality of runoff entering
          the Noosa Springs Lake System to a point where the water quality is better than the
          existing water quality in the lake. Additionally the Noosa Springs Lake System was
          originally designed to provide water quality treatment for the Precinct F and Precinct E2


Job No. M7130_001                                                                                Page 16
                                                                                  Rev 4 : 7 December 2017