2018-05-08 Services & Organisation Committee Agenda

SERVICES & ORGANISATION COMMITTEE MEETING AGENDA                                           8 MAY 2018




                               Figure 2: December 2017 Shoreline Position

It is difficult to predict with absolute certainty what rate of erosion will occur in the future. This is
affected by the impact of existing vegetation which could slow the previous rate of erosion but
could also be accelerated by extreme weather events. What is certain is that the Council would
need to intervene to ensure that no break through would occur to protect the overall purpose of
the Noosa Spit ie protecting Hayes Island (Noosa Sound).

A preliminary analysis based on aerial photography of different erosion timelines has been
undertaken. If the current rate of erosion continues (although the existence of vegetation on
Noosa Spit may reduce that rate of erosion) then by December 2018, the risk of break through is
low. If it continues at the same rate in 2019 and 2020, then the risk increases substantially. The
impact of extreme weather events is also an unknown in terms of the rate of erosion.

The further survey work in July 2018 will provide Council with an important update in terms of the
rate of erosion and allow better modelling in terms of risk assessment.

The Coastal Management Plan (2014) provides best practice guidance for coastal management
and recommends a science based approach that includes deeper understanding through a
formal nourishment transpot model within a Shoreline Erosion Mangement Plan (SEMP). Sand
nourishment is typically recommeneded as a remediation option in the short term.

Implementing a SEMP will require coastal data collection, river and near shore bathymetry
collection, creation of a numerical model that can accurately model sediment transport followed
by a remediation options analysis.

Council officers have applied for grant funding under the Natural Disaster Resilience Program to
assist in the funding of the SEMP development.




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