Storms have already dumped more than a metre (39 inches) of rain in two days in parts of Queensland, engulfing homes, businesses and roads in muddy waters, authorities said.

Aerial footage showed rural communities surrounded by the floodwaters, cut off from nearby roads.

"We are going to see widespread rain and storms spread across much of northern Queensland," the state's premier, David Crisafulli, warned in a news conference.

"We remain prepared for the ongoing prospect of more rain and the likelihood of more flooding, both flash flooding and riverine flooding," he said.

Emergency services carried out 11 "swift water rescues" overnight, the premier said.

Areas of flood-hit Townsville, a popular coastal tourist destination that lies near the Great Barrier Reef, had been declared a "black zone", he said.

"Our advice to residents in the black zone at the moment is to stay out of that zone and stay safe."

The authorities told 2,100 people in the town to evacuate at the weekend, though about 10 percent refused, emergency services officials said.

- 'Bridge torn in two' -

One woman in her 60s was killed Sunday when the rescue boat she was in flipped over in the flood-hit rural town of Ingham, about 100 kilometres (60 miles) from Townsville, police said.

Her body was recovered later.

The floods swept away a section of a concrete bridge over a creek, cutting off the state's main coastal road, the Bruce Highway, the state premier said.

"It's not every day you see a bridge torn in two. That's what has happened at Ollera Creek, and it is significant," Crisafulli said.

Almost 11,000 properties remained without power across north Queensland, Ergon Energy said, with no timeframe given for when electricity will be restored.

Townsville acting mayor Ann-Maree Greaney said the floods were expected to peak on Tuesday morning.

"The roads at the moment are cut off, so communities are isolated," she told AFP.

The town was pressing for power to be restored and working with major supermarkets to deliver food, the mayor said.

As global temperatures rise because of climate change, scientists have warned that heatwaves and other extreme weather events, such as severe flooding, droughts and wildfires will become more frequent and more intense.