Assessment Methodology

o Stress caused by additional (and at times quite large) financial outlays to replace flood damaged possessions; and o Stress caused by family disruption – including for example temporary accommodation, attend different schools, increased distances or time to travel to work. Tangible damages can be further classified as direct or indirect, presented in 5.5. Direct damages are those caused by floodwaters wetting goods and possessions, thereby either damaging them irreparably or reducing their value. Indirect damages are the additional financial losses caused by the flood, including for example: o The extra cost of food and accommodation for evacuees; o Loss of wages by employees; o Loss of actual and prospective production or sales by flood-affected commercial and industrial establishments; and o Opportunity cost to the public caused by the closure or limited operation of public facilities. Assessment Methodology The flood damages assessment methodology is presented below: • Establish design flood modelling results for the 20%, 10%, 5%, 1%, 0.5%, 0.2% AEP and the PMF events. Flood modelling results are derived from the models established in each village (Appendix A to Appendix E), and are based on an envelope of mainstream and overland flooding; • Obtain floor level data o Floor levels for all properties within the PMF extent for each town were estimated by visual inspection and LiDAR data; o The number and type of properties included in the flood damages assessment for each village is provided in Table 7. • Determine the peak flood depth that would occur at each property during each design flood event; • Apply stage-damage curves (derived from DPIE (formerly OEH) Guidelines, Reference 8) to relate the depth of flooding to a monetary cost in each design flood event; • Calculate the Average Annual Damage (AAD). The AAD represents the estimated tangible damages sustained every year (on average), over a long period of time. Note that the results are not an indicator of individual flood risk exposure, but part of a regional assessment of flood risk. Furthermore, the purpose of the damages assessment is not to calculate the actual damage that would be incurred in a flood, but to form a basis of comparison with other flood prone communities throughout NSW, and a baseline against which mitigation options can be assessed. DRAFT FOR PUBLIC EXHIBITION