Appendix J - Civil Engineering Report and SBSMP

                                                                                  Noosa Residential Development
                                                                           Ref: 24553 C R002 REV03 10.08.21.docx
                                                                                                    August 2021


         EXECUTIVE SUMMARY
         ADG Engineers (Aust.) Pty Ltd has been engaged by Stockwell Development Group, to prepare a
         Site Based Stormwater Management Plan suitable for submission to Noosa Shire Council as
         additional information in support of a Development Application for a Material Change of Use at Lot 3
         on SP246584, 17-19 Hofmann Drive, Noosaville QLD 4566.

         The proposed development as shown in Mode Design architectural plans is for three (3) multi-storey
         residential buildings over a shared basement. The building work for the proposed development is to
         form part of separate application submitted to Council for building approval.

         This report is comprised of stormwater quantity and quality assessments. The quantity assessment
         is undertaken to confirm a ‘non-worsening’ of peak flow discharges from the site and the quality
         assessment is undertaken to determine the required stormwater treatment measures to be
         implemented on site.

         The stormwater quantity objective was to demonstrate that there are no impacts from storm events
         up to and including the 1% AEP storm event, which will ensure that the existing infrastructure and/or
         downstream properties are not adversely affected. It has been determined through the use of
         hydraulic modelling that 14.0m3 of On-Site Detention that occurs over the proposed bioretention
         basins is adequate to mitigate the impact of the proposed development and ensure post-
         development peak flows do not exceed pre-development peak flows.

         Currently no quality stormwater management measures are in place for the proposed Noosa
         Residential Development. Stormwater treatment measures are to be implemented on site in
         accordance with Industry Best Practice, WSUD Engineering Guidelines and the Noosa Plan 2020 to
         provide stormwater treatment for this site. The table below provides a summary of the stormwater
         management measures required for the proposed development

           Catchment     Quantity Mitigation Requirement             Quality Mitigation Requirement


               B1         9.7m3 of storage over bioretention                 80m2 Bioretention


               B2         4.3m3 of storage over bioretention                45m2 of Bioretention

                                                                Grass-lined swales that promote settlement
               B3                         Nil
                                                                              of particulates.


         All relevant standards and guidelines are addressed in this Stormwater Management Plan including
         criteria from the Noosa Shire Council Planning Scheme Policies, Queensland Urban Drainage
         Manual 2016, State Planning Policy 2017 Plumbing and Drainage Code AS3500.3 and Australian
         Rainfall and Runoff Guideline.




BRISBANE / SYDNEY / MELBOURNE / GOLD COAST / SUNSHINE COAST / DARWIN / PERTH                             Page 5