Updated

Flooded communities across eastern Australia could be underwater for more than a week, with the cleanup bill expected to hit billions of dollars, a state official said Thursday.

Days of torrential downpours have left parts of central and southern Queensland state inundated, flooding thousands of homes and businesses, cutting off roads and forcing one town's entire population to evacuate.

The rain was easing on Thursday, but river levels continued to rise in many locations as high waters made their way toward the sea. Communities already swamped could remain underwater for up to 10 days, Queensland Premier Anna Bligh warned Thursday.

"The recovery ... is going to require literally billions of dollars from federal, state and local governments (and) insurance companies," she told Australian Broadcasting Corp. radio. "It's an enormous disaster."

Floodwaters inundated 120 homes in the southeast Queensland town of Bundaberg on Wednesday, forcing the evacuation of about 400 people overnight, Deputy Mayor Tony Ricciardi said.

"This is a one-in-100-year event," Ricciardi said. "We won't see this again in our lifetime. Well, I hope."

Two people had to be rescued from their roof after water flooded their Bundaberg home, police said.

In the town of Theodore, the military evacuated the town's entire population of 300 by helicopter on Wednesday. Only a few police officers remained in Theodore, county mayor Maureen Clancy said.

"Certainly the water is still rising," Clancy said. "The heights are at such a new record it's not known what this is going to do."

Queensland launched a disaster relief fund for flood victims with 1 million Australian dollars ($1 million) in state money. Prime Minister Julia Gillard pledged to match that amount with federal funds.

"We won't know until floodwaters recede the total amount of damage done," Gillard said. "But what this does mean is the Queensland and federal governments will work together in those areas in partnership with the rebuilding of critical infrastructure."

Flooding has shut down about 300 roads across Queensland, including two major highways to the state capital Brisbane.

The head of the state's emergency agency, Bruce Grady, said the crisis would not pass quickly.

"These floodwaters are likely to remain high for a long period of time, in some cases that might be measured by weeks, rather than days," he told reporters. "These waters will go down when nature tells us they will go down."