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

                                                              Noosa Coastal Hazards Adaptation Plan



Planning scheme response (development controls)
Planning controls are currently in place for coastal development to limit the encroachment of
buildings and structures into the vegetated dune areas to preserve natural coastal processes of
erosion and sand accumulation. This includes building setbacks from the seaward boundary of lots
through the Noosa Plan 2020, as well as State coastal building lines for some lots under the Coastal
Protection and Management Act.
These planning controls are supported by maintenance of existing vegetated dune areas by Council
and local bushcare groups to enhance these vital buffer areas including active management of
weeds and pests, and fencing and replanting. Further planning is underway to enhance this on-
ground foredune management.
However, this current approach does not fully account for the increased erosion risk anticipated
over the coming decades as a result of sea level rise and projected increases in extreme weather.
Changes to the Noosa Plan 2020 are therefore needed to better plan locally for coastal erosion risks,
consistent with the State Planning Policy for coastal hazards.

Redesign and relocation of key recreational and infrastructure assets
Across the coastal areas, there are numerous recreational and service infrastructure assets that will
increasingly be under threat from erosion overtime. Options for these public assets to be either re-
located outside high-risk areas, or re-designed to be more resilient, need further investigation.

Construction of hard-engineered seawalls (Option is deemed not feasible)
This option involves buried armoured rock seawalls being built for all beach sections identified as
having high or very high erosion risks. These coastal protection works would provide the benefit of
protecting a small number of properties and public assets (relative to the whole local government
area) from damage for the foreseeable future.
The cost-benefit analysis included lengths of wall at the following locations:
    - 110m at Peregian Park (Peregian Beach)
    - 410m adjacent to David Low Way (Castaways Beach)
    - 500m adjacent to David Low Way (Sunrise Beach)
    - 980m adjacent to Tingira Street (Sunrise Beach)
    - 1,960m (entirety of Sunshine Beach)
In all locations, the alignment of a wall would need to be located significantly seaward of the
assets for which protection is sought in order to mitigate impacts associated with wave run-up and
overtopping (i.e. slumping of dune landward of the structure).
The seawall is also highly likely to exacerbate erosion of the beach seaward of the structure by
slowing the replenishment of the beach. The loss of sandy beach that would be a virtually inevitable
result of this option would negatively affect recreation, tourism, scenic and ecological values
associated with the beach on a significant scale.




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