UPDATED DA - Attachment 7 - Flood Impact Assessment

     4.0    CONCLUSION
     Covey Associates has been engaged by Noosa Council to provide a Flood Impact Assessment for a Recycle and Transfer
     Station Centre and associated infrastructure at 561 Noosa-Eumundi Rd, Doonan.

     Ensemble storm hydraulic (TUFLOW) flood modelling in accordance with ARR 2019 guidelines was undertaken for
     existing and developed case scenarios for the 50%, 10%, 1% and 1% climate change Annual Exceedance Probability
     (AEP) events.

     The flood mapping demonstrated that generally the on-site overland flow paths adequately conveyed both internal
     and external catchment flows. Further, as a result of the proposed development, there is a negligible change in peak
     water level, depth, velocity and hazard on the surrounding properties for all modelled AEPs.

     Through this assessment, it has been demonstrated that the proposed development and associated infrastructure will
     not result in any actionable nuisance to any of the surrounding properties or infrastructure with regards to overland
     flow. Further, based on the results of this study, on-site detention is not required for the development.

     Sufficient consideration of stormwater water quantity controls has been demonstrated by:
     •        Compliance with the requirements of the Noosa Plan (2020);
     •        Queensland State Planning Policy (2017); and
     •        Compliance with QUDM (2017).

     5.0    References
     Department of State Development, Infrastructure and Planning (2017) State Planning Policy. Brisbane, Queensland.

     Institute of Public Works Engineering Australia, Queensland Division Ltd (2017) Queensland Urban Drainage Manual,
     Fourth Edition.

     Noosa Shire Council (2020) Noosa Plan




Noosa Shire Council                                                                                  11
M25-0045Rpt – 244035– February 2025