In non-urban areas, where the flood response is also dependent on antecedent catchment conditions , there is no evidence of increasing flood magnitudes in Australia , except for the most extreme events . Modelling studies project increases in flood magnitudes in northern and eastern Australia and in western and northern New Zealand  . The change in flood magnitude in southern Australia is uncertain because of the compensating effect of more intense extreme rainfall versus projected drier antecedent conditions . Higher rainfall intensity and peak flows also increase erosion and sediment and nutrient loads in waterways  and exacerbate problems from ageing stormwater and wastewater infrastructure .
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report