2021-01-18 GC - Item 3 - Attachment 2 - Phase 7 Project Summary Coastal Hazards Adaptation Plan

 Noosa Shire Council Coastal Hazard Adaptation Plan: Project Summary                                        28
 Findings




         with tide flaps /valves on the stormwater network to limit penetration onto roads and properties via
         this path. Raising footpath levels rated lower than modifications to the stormwater network due to the
         potential for increasing impacts on the road network.

         At Dog Beach, the highest ranked options to manage sea level rise and storm tide risks were active
         dune and habitat management as well as dune augmentation, which rated higher than manual creek
         channel management.

         Major infrastructure such as tidal gates or surge barriers, although benefitting more than just the
         Noosa Heads locality, rated poorly for all parts of Noosa Heads, largely due to the significant costs,
         environmental and social impacts, and complexity of gaining approvals.

3.5.5    Noosaville
         Sea level rise and storm tide expose numerous areas within Noosaville and around Lake Weyba to
         high and very high risks.

         Hazard resilient design for public and private infrastructure rated well for both hazard types, along
         with modifications to the stormwater network to reduce penetration into inland areas and build
         redundancy into the system to ease impacts where possible. Options such as raising road or footpath
         levels rated more highly than major infrastructure such as levees and tidal gates but would need to
         be done in conjunction with stormwater network management measures for optimal benefit. Land
         buy back and land swap rated poorly due to the major cost and social implications.

         Although levees rated poorly due to the costs involved, the wider community benefit may outweigh
         this. Similarly, although road raising rated poorly, the road network through Noosaville provides
         important connectivity between Noosa Heads and Tewantin.

3.5.6    Tewantin
         Assets at high risk or very high risk from sea level rise include residential areas (including roads and
         associated utilities), Noosa Marina, Tewantin end of the Noosa River Ferry landing, and the foreshore
         parklands. Design of hazard resilient infrastructure rated highly for this locality, as did rolling
         easements and land management to support habitat migration, both of which could only be
         implemented in selected areas. Levees, land buy back and tidal gates all rated poorly, driven by high
         economic, environmental and/or social costs.

         Only the foreshore parkland areas at Tewantin were at high risk from storm tide, with affected assets
         mainly park infrastructure and associated utilities such as stormwater, electricity etc. The assessment
         shows that designing hazard resilient infrastructure and stormwater network management actions
         rated highly. The relatively short section of levee (and therefore lower cost) required to protect the
         parklands elevates this option within the rankings, particularly compared to river walls with high crest
         levels and tide gates. Master planning of public lands, while reducing impacts on infrastructure, does
         not reduce risks on the broader usage of the land.

3.5.7    Noosa North Shore
         For private riverfront development including the rural fire brigade facility on Noosa’s North Shore,
         design resilient infrastructure was the highest ranked option to mitigate against risks from storm tide