ECM_22343537_v1_Coastal Hazard Assessment · 132000.200173.1

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              5.1.3       Storm Tide
              Storm tide is the total water level associated with the combination of the normal astronomical tide and the
              tidal surge from a storm event (e.g., tropical cyclone). There have been several previous storm tide
              studies undertaken for the Sunshine Coast with the most recent being the ‘Sunshine Coast Storm Tide
              Study’ (Aurecon, 2013). The design storm tide levels determined by Aurecon (2013) for the 100, 500 and
              1000-year ARI events are presented in Table 2.

              Noosa Shire Council has undertaken a broad-scale reassessment of coastal hazards from Peregian
              Beach to Teewah Beach as part of the ‘Noosa Shire Council Coastal Hazards Risk, Vulnerability and
              Adaptation Assessment’ (BMT, 2018). The 100-year ARI storm tide level of 1.74m AHD was adopted by
              BMT (2018) for the reassessment of the erosion prone area width at Sunshine Beach.

              To address the SDAP (Performance Outcome 6 of State Code 8) outlined in Section 4.1 the vulnerability
              of the proposed property and house to an extreme storm events has been considered and assessed. As
              discussed in the introduction, a 500-year ARI storm tide level has been adopted for the extreme analysis
              with an allowance for climate change induced sea level rise of 0.8 metres. The extreme event
              assessment is discussed further in Section 6.1.2.
              Table 2 Adopted Storm Tide Levels (excluding wave setup) for Sunshine Beach (Aurecon, 2013)


                                                                                 Current Climate
                                                         Return Period
                                                                                Storm Tide Level
                                                          (years ARI)
                                                                                    (m AHD)

                                                              100                      1.74

                                                              500                      1.84

                                                              1000                     1.89




              5.2         Wave Climate
              The wave climate at Sunshine Beach is influenced by both locally wind-generated sea and ocean swell.
              Sea describes wind generated waves where wind energy is still being transferred to the ocean. Swell
              describes wind generated waves that have travelled out of their generating area. Swell characteristically
              exhibits smoother, more regular, and uniform crests and a longer period than sea. In open coastal areas
              sea waves generated by local winds are often superimposed on swell waves.

              The wave climate for Sunshine Beach has been previously reported by BMT (2013), ‘Coastal Processes
              Study for the Sunshine Coast’ prepared for the Sunshine Coast Regional Council. Wave roses shown by
              BMT WBM (2013) indicate that the wave climate for Sunshine Beach is dominated by waves from the
              east-southeast direction (refer Figure 16).

              The design offshore significant wave heights for the Sunshine Coast have been previously published by
              BMT (2013), refer Figure 17. For this assessment a 100-year ARI offshore significant wave height of 6.2
              metres has been adopted to be consistent with the ‘Coastal Processes Study for the Sunshine Coast’
              prepared by BMT (2013).




              13 February 2023         2 ARAKOON CRESCENT, SUNSHINE BEACH                                   PA3303   21


Document Set ID: 22343537
Version: 1, Version Date: 16/03/2023