2021-10-08 SM - Item 1 - Attachment 2 - Draft Coastal Hazards Adaptation Plan - tracked changes

waters is going to increase beyond what we currently identify as the shoreline and this is also due
to increases in sea level.

Flood management measures are currently in place in Noosa Shire to help manage the risks of
flooding as a result of high rainfall in the catchment (referred to as catchment flooding). These
include:
      stormwater drainage works and flood mitigation works in high-risk flood prone areas
      planning controls through the Noosa Plan 2020 that set development requirements such as
         minimum levels for new buildings and filling limits for land subdivisions and other works
      flood modelling and mapping identifying areas at risk for different flood severities
      Disaster management responses during major flood events.

These catchment flooding measures will also help Noosa manage and adapt to changes to storm
tide inundation. For example, the minimum floor levels for new houses or units in Noosaville will
ensure that these developments are safeguarded from direct physical damage from storm tide
inundation.

However, the impacts of frequent tidal inundation of low-lying areas (particularly the parks, road
reserves and some private properties around the Noosa River) require further management action
overtime. Some riverside areas are already affected by infrequent events such as catchment
flooding and storm tide inundation. The relatively long periods of time between events allow for
clean-up, recovery and repairs to be undertaken, and normal activities to resume unimpeded.
However, activities and assets in these areas are unlikely to cope with impacts caused by frequent
tidal inundation. As sea levels rise, some low-lying areas will be regularly covered with shallow sea
water. In the absence of any adaptation response, this inundation will likely restrict access to
roads, footpaths and recreational areas and cause nuisance to residents, business owners and
visitors.

The cost benefit analysis of coastal inundation risks8 assessed that a number of adaptation options
are likely to be both suitable and feasible for responding to the risks associated with frequent tidal
inundation in Noosa’s coastal zone. These include:

         Continuing existing measures for responding to risks of catchment flooding and storm tide
          inundation
         Protecting buried infrastructure (stormwater and sewerage assets) through installation of
          innovative technologies
         Reducing the frequency of inundation to roads, pathways, parks and business areas
          through the creation of adaptive landscape measures. This includes low rise levies (see
          Factsheet #1) and landscaped walls along some foreshore edges, elevated footpaths and
          improvements to drainage
         Ensuring asset plans and upgrades appropriately consider inundation risks.

Fact sheets for these adaptation measures can be found on the project page on Your Say Noosa.




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    Aither, 2020. Noosa Shire Council CHAP – Phase 7, Noosaville Cost Benefit Analysis
Noosa Council – Coastal Hazards Adaptation Plan 2020 - 2030                                   Page 31