2019-12-16 GC Agenda - Item 5 - Attachment 1 - Noosa Spit Shoreline Erosion Management Plan-Part 1

Noosa Spit SEMP Final Report                                                                               63
Shoreline Erosion Mitigation Options




        • Accommodate the risk aims to retrofit (or redevelop) existing infrastructure and development in
          a manner that minimising damage and other losses. May also include existing shoreline
          management activities.

        For the risks posed to existing assets and development, it’s often useful to define ‘trigger points’ for
        implementation of promoted management options. This is especially true when the risk to assets is
        uncertain and expected to change over time. The trigger-based approach acknowledges uncertainty
        in natural coastal processes (such as rapid events that cause shoreline erosion or storm tide
        inundation) and the success of management actions. It is underpinned by ongoing monitoring and
        performance criteria to identify changes in risk profile which trigger actions to achieve an overarching
        coastal management objective.

        This conceptual approach is illustrated in Figure 4-1 for a shoreline with an overarching management
        objective to maintain a sandy beach that provides a buffer to coastal processes and social values.
        Beach nourishment is the preferred management action to achieve the objective in this example;
        however, it is recognised that this action alone may not sufficiently treat the risk or be viable over a
        longer-term planning period. The strategy includes a trigger for a seawall once the risk to land-based
        assets can no longer be treated by beach nourishment.

        Prior to the seawall trigger being reached, planning controls, ‘no regrets’ actions and preliminary
        investigations must still be undertaken to plan for the investment in future actions. No regrets and
        preliminary actions are typically low cost with little or no undesirable consequences. In some cases,
        these actions simply represent ‘business as usual’ for Council and/or investigations needed to
        support the design and implementation of the promoted management options.

        Table 4-1 lists the management options considered to address the potential coastal hazard risks at
        Dog Beach and Noosa Spit. The broad options were initially considered through engagement with
        the PCG and DES followed by the application of the ‘rapid assessment’ presented below in Section
        4.2.1. It is noted that an effective coastal management strategy for Noosa Spit is likely to require a
        combination of options over time.




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