MCU25 0087 - Reference Document - Coastal Hazard Assessment (As Published)

                                                                   17 The Esplanade, Sunshine Beach                              Report




                      Figure 5-1 ETA 602 location in relation to 17 The Esplanade, Sunshine Beach and Noosa Headland

                      5.2.2    Short-term Erosion (C)
                      The Department of Environment and Heritage Protection (2013) recommends the calculation of short-
                      term erosion based on a 100-year ARI storm event using the method developed by Vellinga (1983).
                      The equation developed by (Vellinga, 1983) is as follows:
                                              .                         .
                        7.6             7.6          𝑤     .
                            𝑦 = 0.47                           𝑥 + 18       − 2.00
                        𝐻               𝐻         0.0268
                      Where:
                      𝐻     = Deep water significant wave height (metres)
                      𝑤 = Fall velocity of sand (metres/second)
                      𝑥 = The distance from the dune foot (metres)
                      𝑦 = Depth below storm surge (metres)
                      The relationship between sediment grain size and fall velocity has been derived from laboratory tests
                      and is given by the following equation (Vellinga, 1983):
                            1
                      log     = 0.476(log     𝐷) + 2.18 log    𝐷 + 3.19
                            𝑤
                      Where:
                      𝑤 = Fall velocity of sand (metres/second) in still water of 10oC
                      𝐷 = The grain size of the sand (metres)




                                                                                       252662-MN-RP-CO-0001B | 10 November 2025 | Page 23

Document Set ID: 24631530
Version: 1, Version Date: 24/03/2026