River flows were well above average for the fourth year in a row, while the extent of wetland flooding increased from the previous year.
National river inflows were 129 mm or 1.02 million GL; 6% less than previous year but 37% above the 2000–2023 average.Conversely, along the SA coast and southwest Victoria, river inflows were below average, in some cases the lowest since 2000. River inflows were high or above average in parts of the Northern Territory and Central Australia and in the Greenough River catchment in WA.
Australia experienced major flood events in early 2024, mainly in the north, with some rivers reaching record-high flows. In January, the monsoon triggered major floods in the Katherine, Daly, and Victoria rivers in the Northern Territory, while ex-Tropical Cyclone (TC) Kirrily caused flooding in the Nicholson, Gregory, and Flinders rivers in Queensland. February and March saw continued heavy rain from ex-TCs Lincoln and Megan, leading to major flooding in the Flinders River and Eyre Creek in inland Australia.
In April, low-pressure troughs brought weeks of flooding to western and southern Queensland. By June, heavy rain along the New South Wales coast caused Nepean River flooding, with Warragamba Dam reaching capacity and spilling multiple times.
Between late August and early September, heavy rainfall caused major flooding in Tasmania’s Derwent and Meander rivers. In mid-December, a coastal trough brought heavy rain to south-eastern Queensland, leading to renewed flooding in the Mary, Burnett, and Logan rivers.
Storage in the various water reservoirs in the Murray-Darling fell for a second year, from 84% to 72% of capacity, but remained above average. Reservoir storage in the Ord system in the Kimberley region increased for a third year, from 86% to 97% of capacity.
Urban water supplies for Sydney, Melbourne and Canberra remained high for a second year, at 86- 99% of capacity, while water supplies for Brisbane increased from 70% to 89%. Water supplies for Adelaide declined by 22% of capacity, from 67% to 45%, whereas Perth water supplies remained nearly unchanged at 46%.
The area inundated during all or part of the year was above average for the third year in a row, covering 10% more area than in 2023 and 43% more than the 2000-2023 average.
Maximum flood extent decreased or remained stable across most of Australia, with increases in some northern Australian catchments. The highest water extent since 2000 was observed in several catchments along the northern Australian coast and in Far North Queensland.
