A man was seen clutching a tree as the gushing water swept down a street, pushing vehicles off the road, into each other and flinging one van into trees.
The Queensland region has recently been devastated by heavy rain and overflowing rivers, submerging entire towns. Some areas have had more than 13 inches of rain in just 24 hours.
Around 1,200 homes were flooded and 11,000 more have some water damage. Nearly 4,000 people have been evacuated. Australian officials call it the worst flooding in decades.
Authorities said the price of rebuilding homes, businesses and infrastructure, coupled with economic losses, could be as high as $5 billion.
The Associated Press contributed to this report.