2021-10-08 SM - Item 1 - Attachment 1 - Draft Coastal Hazards Adaptation Plan

Options for responding to coastal erosion risks
Beach conditions naturally change over time as a result of various tide, waves and wind and
conditions combining to erode and replenish sand.

However, due to sea level rise a trend of continuous, gradual erosion of sand from the beach
resulting in long-term shoreline recession is expected. Development and other disturbance of the
natural dune system by human activities increases the erosion potential by interrupting the natural
beach and coastal processes of erosion and sand replenishment. Therefore, eroded coastlines
may increasingly fail to rebuild fully following extreme events, increasingly the likelihood of
permanent loss of beach areas and dunes if appropriate adaptation measures are not undertaken.

Decisions made today may have ramifications for several decades or more, depending on the
asset type and the life of the asset, or the adaptation measure pursued. For example, it is
reasonable to expect a house built today to still be in place in as much as 40 years’ time, with
some modifications. A public amenities block or picnic facilities may have an asset life of just 10
years until renewal is considered. Therefore, consideration of short, medium, and long-term
timeframes (i.e. as far as the years 2070 and 2100) is important when assessing appropriate
response to coastal erosion risks.

Local government has a responsibility to make well considered decisions and land use policy that
takes account of longer time horizons using the best information available at the time and to review
this as more information develops. Taking an adaptable and staged approach to managing coastal
erosion risks is essential to managing these risks across both the short and long term on behalf of
Noosa’s present and future community.

The technical studies performed throughout phases two through seven of this project, as well as
multiple rounds of community input, have revealed a set of adaptation options deemed most
appropriate for responding to coastal erosion risks in Noosa. These include:
    Dune revegetation and management
    Beach nourishment, dune augmentation and management
    Planning scheme response (development controls)
    Redesign and relocation of key recreational and infrastructure assets.

Options relating to the ‘Construction of hard-engineered seawalls’ and ‘Acquisition of private
residential properties’ were not deemed appropriate or feasible.

Dune revegetation and management.

This option includes revegetation and maintenance of at-risk dune areas, including weed and pest
control and fencing. This nature-based option is considered a preferred and feasible response for
mitigating coastal erosion risks due to the relatively low cost, high community support, ease of
implementation, consistency with the current scenic amenity of Noosa’s coastline, and lack of
adverse impacts. Importantly, this low-risk management response provides benefits by providing
support for existing beach uses (e.g. recreation), supporting ecological values (beach and dune
system), visual amenity, as well as offering some level of protection against the effects of a coastal
erosion event. Ongoing efforts to support dune growth and recovery are expected to delay any
potential damage to properties and assets by helping to preserve the dune profile and stability for
longer than if no management intervention were made.




Noosa Council – Coastal Hazards Adaptation Plan                                               Page 26