2021-11-15 GC Agenda - Item 7 - Attachment 1 - Coastal Hazards Adaptation Plan

                                                                       Noosa Coastal Hazards Adaptation Plan



For this plan, a range of storm tides of differing magnitudes were modelled for each of the four
planning  horizons.
 For this plan,       Figure
                 a range      8 shows
                           of storm     an of
                                    tides  example
                                              differingofmagnitudes
                                                           storm tide extent,  for the year
                                                                       were modelled        for 2100
                                                                                                    19
                                                                                                each of. Additional
                                                                                                          the four
 planning
images     horizons.
         showing   theAs   a resultAverage
                        100-year    of the topography
                                             RecurrenceofInterval
                                                              the lower  Noosa
                                                                     (ARI)  storm  River,  the project
                                                                                     tide extent  across found  that
                                                                                                            the entire
 the area
coastal    of land
         zone       exposed
               for other  yearstocan
                                  major
                                     be storm
                                         found tide   event is less
                                                 in Appendix         than map
                                                                3. These   that which
                                                                                  layers would    be be
                                                                                           can also  expected
                                                                                                          exploredto
 occur  during  a major   catchment   flood  event   following  major  rainfall 5. Figure 8 shows an example of
in greater detail using Council’s mapping website. It is important to note that as a result of the
 storm tide extent,
topography            for theNoosa
              of the lower    year 2100.
                                    River, Additional
                                           the projectimages      showing
                                                          found that        theof
                                                                     the area    100landARI   storm tide
                                                                                           exposed    to aextent
                                                                                                            major storm
 across  the entire  coastal   zone for other  years   can   be found  in Appendix      3. These
tide event is less than that which would be expected to occur during a major catchment flood event map    layers can
 also be explored in greater detail (including for other scales of storm tide event) using Council’s
following major rainfall (of which land use and infrastructure planning already considers)21.
 mapping website.




                       Figure 8 - Area of land subject to a 100-year ARI storm tide event in 2100
                          Figure 8 - Area of land subject to a 100 ARI storm tide event in 2100

19
    azard extent has been derived using methods described in Aurecon (2013: Sunshine Coast Storm Tide Study –
   H
   Storm Tide Definition, prepared for Sunshine Coast Regional Council) and Airborne Laser Scanning data captured in
   2010. Inundation depths are derived from water levels that do not include any freeboard allowance.
21
   As described in Noosa Council (2017)’s Noosa River Flood Study Upgrade.
 5
     As described in the 2016 flood study undertaken by Noosa Council.
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 Noosa Council – Coastal Hazards Adaptation Plan                                                             Page 21