NOOSA home builders in designated flood areas would have to start building .3m higher than present standards under proposed council planning changes yet to be adopted.
And Noosa Council has been told that these amendments should start factoring in climate change and the threat of flooding as staff warn councillors to expect sea level rises of .8m by 2100, plus increases in extreme weather events and frequent flooding.
Senior strategic planner Rowena Skinner’s report to last week’s planning committee stated “one of the greatest threats to people and property in Noosa Shire is natural disaster from flooding”.
A further report on Monday to the committee said about 1000 properties would be affected by new flood hazard mapping, with 490 in the Mary River catchment, 189 in the Cooroy Lake Macdonald area, 150 in Noosa Heads and 36 in Noosaville.
Ms Skinner said it was important the community was provided with the best flood information and appropriate measures to mitigate flood risk and disaster, taking into consideration the current climate and potential future climate conditions
Ms Skinner said new mapping “adopts an 800mm sea level rise and 20% increase in rainfall intensity by the year 2100”.
If this advice was taken on board and the new flood maps adopted, she said this would increase the height properties were required to be developed to achieve the desired flood standard of immunity for the next 50 years.
“This means that the habitable rooms such as bedrooms, kitchens and living rooms of new or extended properties in these areas may need to be built 300mm higher than currently,” she said.
“This additional floor height is considered to be readily achievable through appropriate design and site layout.”
Ms Skinner said the proposed 300mm of freeboard was considered an appropriate safety factor given the conservative climate change allowance.
“By taking into account predictions for future sea level rise, in the short term this will provide an additional level of flood immunity.”