How can Sydney's communities become more resilient to flooding disasters?
The answers may lie in the way communities have previously responded.
Professor Elizabeth Mossop from the University of Technology Sydney's design school spent 10 years in New Orleans following Hurricane Katrina.
She looked at how the city rebuilt and became better equipped to deal with flooding after the storm wreaked havoc in 2005.
Professor Mossop told ABC Radio Sydney Breakfast host James Valentine that watercourses needed to be managed so floodwaters could flow out more easily, which would reduce the impact on homes and businesses.
"Are there things that we can do in terms of more conventional engineering, like levees and floodwalls?" she said.
"Are there things that we can do to try to make the existing buildings that are in these places to make them more resilient to floods?"
Professor Mossop says evacuation routes also need to be improved, particularly for those who might not have their homes flooded but are cut off during emergencies.
"We've got to look at every possible strategy that might be in the toolkit to try to mitigate the risk for the people who already live in these areas," she said.
New Orleans was slammed by Hurricane Ida in August last year, testing the city's newly-built flood resilience measures.
The result was less persistent damage from the subsequent flooding than when Katrina hit, Professor Mossop said.
"They did a huge amount of work on their drainage and flood infrastructure," she said.
Indigenous knowledge 'will go a long way'
Ngame man and Brewarrina Shire utilities manager David Kirby said Indigenous people had been observing and dealing with floods in Australia for thousands of years, but Western science had not properly embraced their knowledge.
He said ignoring that knowledge had contributed to the issues being faced in Sydney's west and north-west.
"Some of the planning laws which have been adopted [are based on] rainfall data that is only accurate by 80-90 years," Mr Kirby told ABC Radio Sydney's Mornings program.
Indicators of previous floods – such as rocks with marks on them demonstrating a severe inundation hundreds of years ago – are familiar to some Indigenous experts.
But Mr Kirby said Western science did not accept indigenous knowledge because it was mostly oral.
"If Western science or mainstream society was more open to how we actually use that type of knowledge, I think it will go a long way," he said.
Mr Kirby warned that ignoring thousands of years of experience would result in planners repeating the same mistakes.
"I can guarantee you we are going to see things … that people will think are unspeakable, when it comes to climate change and rainfall variation," he said.
