One person killed and others trapped in cars as Queensland continues to deal with worst flooding in decades

Flash floods swept through a Queensland community today, killing one woman, trapping others in cars and leaving some clinging to trees in a region battling its worst flooding in decades.

The torrent of muddy water swamped the city of Toowoomba, west of the state capital, Brisbane, killing one female pedestrian, a state police spokeswoman said.

Video footage of the scene shows a man clutching a tree as the water sweeps down a street, pushing vehicles off the road, into each other and flinging one van into trees.

"We've had multiple calls requesting urgent assistance from people caught in vehicles, caught on the street, caught in flood ways," Queensland's deputy police commissioner, Ian Stewart, said. "This has just evolved. There has been no warning of this event."

The state has been devastated by weeks of heavy rain and overflowing rivers. Eleven people have died since late November and about 200,000 have been affected by the floods. Roads and rail lines have been cut off, the coal mine industry has virtually shut down, and cattle farming across a large part of the state is at a standstill.

Footage from the Toowoomba flooding captured the rescue of one man hanging on to a tree. Others were stranded on the roof of a building, and on the roof of a submerged car. A spokeswoman with the Department of Community Safety said rescue operations were under way.

Toowoomba resident Sarah Gordon said she saw at least 15 cars washed away by the floodwaters.

"A lot of cars got swept down the road ... right down the creek," she said. "A few people were trapped, but they luckily got out."

The water also inundated city businesses.

"The water was lapping at our office door and was just leaking through," said Emily Hart, who works in an estate agents. "It all happened within a matter of an hour. It was a massive amount of water."

Muddy waters flowed through the main street in the city of Gympie, the latest of about 40 communities in Queensland to be affected by overflowing rivers. Residents were sandbagging buildings, but about a dozen businesses were flooded by today and dozens more were at risk as the Mary river burst its banks and continued to rise.

The latest flooding was not as bad as in recent weeks, when entire towns were submerged beneath an inland sea the size of France and Germany combined. But it was a sign the ground has little capacity left to soak up any more moisture, so any new rain is likely to make matters worse, officials said.

Queensland officials have said the price of rebuilding homes, businesses and infrastructure, coupled with economic losses, could be as high as $5bn.

Some areas of Queensland had had more than 340mm (13in) of rain in the past 24 hours, the Bureau of Meteorology said.

Up to 80 businesses and homes were at risk of being inundated in Gympie, a city of about 16,000, the acting regional mayor, Tony Perrett, said. Police were planning to knock on doors in high-risk areas, warning residents they may need to leave.

Residents of the town of Dalby, west of Brisbane, were evacuated today as rising water threatened to inundate homes that had just begun drying out after flooding two weeks ago.

Dalby's mayor, Ray Brown, said the town had been cut in half by the swollen Myall creek, which also overflowed on 27 December, leaving 100 homes under water. The town had experienced several smaller floods in the past month.

Heavy rains were leaving low-lying communities along the Brisbane river, which flows through Brisbane, vulnerable to flash flooding, the Bureau of Meteorology warned. Officials have offered residents sandbags and suggested they have emergency kits ready.

Residents of some of the affected communities have returned home and begun cleaning up, while others – including in Rockhampton – are still waiting for floodwaters to recede.

Water levels remain high in Rockhampton, and the mayor warned residents evacuated two weeks ago that they faced another week of waiting before it would be safe to return home. Muddy water is still sloshing through 400 houses and 150 businesses in the city.

Australia's worst flooding in some 50 years was caused by tropical rains that fell for days, starting just before Christmas. About 1,200 homes were inundated and almost 11,000 more have water damage. Nearly 4,000 people were evacuated, and many are still staying with friends or in relief shelters.