2018-12-11 Planning & Environment Committee Agenda

PLANNING & ENVIRONMENT COMMITTEE MEETING AGENDA   11 DECEMBER 2018




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PLANNING & ENVIRONMENT COMMITTEE MEETING AGENDA                                11 DECEMBER 2018

   2.2.   Coastal Processes
   It is understood that Noosa Shire Council is currently developing a Coastal Hazards Adaptation
   Strate gy (CHAS) in consultation with the Department of Environment and Science. The CHAS will
   undertake a detailed review of coastal processes and revise the erosion prone area based on the
   information obtained. In relation to the erosion potential the CHAS will consider the wave climate,
   storm tide estimates and sediment supply along with historical beach movements.
   The wave climate for Sunshine Beach has been previously reported by BMT WBM (2013), “Coastal
   Processes Study for the Sunshine Coast” prepared for the Sunshine Coast Regional Council. BMT
   WBM (2013) has shown the wave climate for Sunshine Beach is dominated by waves from the east-
   southeast direction (refer Hgure 2-5).

                                   N

               NW                                oN NE
                  oe
                yf
         WNW                   *                           ENE

         wsw                   '                        L
                Ys                                   /
                sw                  :              / SE
                       SN “|
                        ssw                  SSE
            J                       s
          (    15% )                             ms hhh
               30%

            \                                   0 04 081216 2 24 26 32 36 4
            —                                         Hsig [m]

   Figure 2-5 Wave Rose for Sunshine Beach from BMT WBM (2013)
   BMT WBM (2013) stated that the current 100 year ARI storm tide level, including an allowance for
   wave setup, for Sunshine Beach is 2.61m AHD. Allowing for future projected sea level rise of 0.8m
   by 2100 would equate to a 100 year ARI storm tide level of 3.41m AHDat 2100.
   The other factor that will influence erosion potential at Sunshine Beach is sediment supply. BMT
   WBM (2013) review the sediment transport between Caloundra and Noosa and found, “There is a
   net northerly longshore sand transport potential within the study area that increases progressively
   from approximately 3,700m per year at Currimundi Beach to approximately 23,300m? per year at
   Sunshine Beach”. BMT WBM (2013) established that, in relation to Sunshine Beach, “A well
   established dune and vegetation buffer allow the beach to respond naturally to erosion events” and
   “At present, the erosion threat to development is considered low”.

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