From 20 – 26 February 2020, a surface trough extending through the interior of Queensland interacted with an upper-level trough to produce showers and thunderstorms that generated moderate to locally heavy falls through southern inland Queensland and over to the Capricornia coast.
Some sites in the state’s south-west had their highest total February rainfall on record or their highest total February rainfall for at least 20 years. The rainfall produced very significant river levels in catchments across the Warrego and Maranoa district, resulting in the highest river levels since the very significant 2012 floods.
Major flood levels were recorded across the Balonne River catchment including at the townships of Surat, St George and Dirranbandi. In the nearby Wallam Creek catchment, major flood levels were recorded at Bollon and also further west in the Bulloo River at Quilpie. Significant river levels were also recorded on the Maranoa River at Mitchell and in the Warrego River catchment where moderate flooding peaked just below the major flood level at Charleville.
By Tuesday 25 February, floodwaters in the Warrego River at Charleville were falling after reaching a peak of 5.7 metres on the Monday night, below the expected 6.3 metres.
That same day at St George 300 kilometres (km) to the south-east and about 500km west of Brisbane, Queensland Police issued an emergency declaration for the Balonne River from Beardmore Dam to the Queensland-NSW border and urged residents to avoid using personal watercraft in the water system. The State Emergency Service (SES) deployed four extra swift water rescue crews to the area and SES volunteers visited residents, advising them to prepare to evacuate after dozens of homes in low-lying areas were threatened by rising floodwaters.
The SES also ran medical supplies from Roma to towns and outlying properties north of St George already cut off by floodwaters. Boat operators around the Maranoa assisted pharmacies resupply vital medications to elderly residents.
The following day, floodwaters at St George continued to rise and closed one of the main arterial roads. The Balonne River, which runs through the town, was expected to peak at about 12.5 metres on the Thursday.
Further west at Quilpie on the Bulloo River, up to 200 millimetres of rain fell, cutting the town off and causing evacuations in nearby Adavale and Eromanga. Trucks were stranded on remote cattle stations and livestock was moved to higher ground. The only way to move around the district and to get supplies to remote farming properties after floodwaters cut roads was by air.
Until these significant rains arrived, Queensland’s southern interior and south-west had been crippled by about ten years of drought. Most locals welcomed the rain.
Joint Commonwealth-State disaster recovery funding was made available for counter disaster operations and the restoration of essential public assets in six local government areas in southern and south-west QLD impacted by the heavy rainfall and flooding.