2021-01-18 GC - Item 3 - Attachment 4 - Cost Benefit Analysis for Noosaville Inundation Options

Table 4: Next steps for assessment

 Assumption                   Confidence      Sensitivity   Description

 Costs of options             Medium          High          Costings for levees, stormwater modifications
                                                            and road raising are an early stage estimate.
                                                            Further assessment should be undertaken to
                                                            support more robust cost estimates.

 Value of recreational        Low             High          It is difficult to fully value the benefit of access
 areas                                                      to recreational areas. Community consultation
                                                            could provide further insights on the associated
                                                            benefits of reducing inundation to recreational
                                                            areas.

 Damage to                    Low             Low           As well as reducing access to recreational areas,
 recreational areas                                         inundation is likely to cause damage that will
                                                            require repair and maintenance which will be an
                                                            additional cost to council, and will further affect
                                                            access. A better understanding of these costs
                                                            would further support the analysis.

 Property damage              Low             Medium        Currently, property damage is calculated based
                                                            on the costs of dryland and urban salinity.
                                                            Further work could be undertaken to better
                                                            understand the costs to properties from
                                                            frequent low-level inundation in the Noosaville
                                                            area.

 Effects on tourism           Low             High          It is assumed that inundation will have a
                                                            negative effect on tourism in the Noosaville
                                                            area, however the magnitude of this impact is
                                                            not well understood. Further engagement with
                                                            the community and visitors could provide
                                                            insights into the negative effects of inundation
                                                            on tourism.

 Road and stormwater          Medium          Medium        It is assumed that inundation will have a
 network damage                                             negative effect on roads and stormwater assets,
                                                            reducing their lifespan and increasing
                                                            maintenance costs for council. However, the
                                                            magnitude of the expected impacts are not well
                                                            understood, further work to refine the estimates
                                                            of changes in lifespan would support more
                                                            robust future cost estimates.




REPORT | Noosa Shire Council CHAP – Phase 7                                                                    10