The 2021-2022 floods across eastern Australia highlighted the vulnerability of rivers to changing climate extremes. They are the costliest natural disaster in Australia’s recorded history with insured losses of ~$6.41 billion, well ahead of the 2019-20 ‘black summer’ bushfires (ICA 2022). By 2050, Australia’s annual extreme weather cost is likely to be $32.5 billion (ICA, 2022).
The 2022 NSW Government inquiry into the floods calls for implementation of “nature-based flood mitigation … using floodplains as assets … and letting watercourses largely flow naturally rather than implementing engineering barriers such as flood levees and mitigation schemes to stop floods” (O’Kane and Fuller, 2022). In this context we must urgently re-examine how to live with rivers and build nature-based flood mitigation capacity and resilience into them, to prepare for an inevitable future where floods are forecast to be more intense and extreme. So, how do we achieve this?
Natural Flood Management (NFM) uses natural processes to slow floods down, reduce their erosive power, and reduce flood risk. I will describe the geomorphic, vegetative and hydrological recovery that is happening in coastal catchments of NSW and the NFM signals that are emerging. I will then consider how we realise NFM on-the-ground by using and applying all the nature-based tools we have in the toolbox to enhance river recovery and deliver flood mitigation to communities. I will use the 2021-2022 floods as a case study to demonstrate the potential for delivering NFM and river recovery in 21st Century river management (Fryirs et al., 2023).