Melbourne: Surging floodwaters broke levees in disaster-hit Australia on Monday to inundate more properties in the southeast, as residents sandbagged homes against the spiralling crisis.
Swollen rivers in the southeastern state of Victoria have created a flood zone measuring an estimated 90 kilometres (56 miles) long and 40 kilometres wide, the State Emergency Service said.
"This area has seen unprecedented flooding," SES spokesman Kevin Monk said to a news agency. "This is just amazing."
As the floodwaters rushed towards the Murray River, evacuation alerts were issued late Sunday and early Monday for the small communities of Pental Island and Murrabit West, home to about 400 people each.
In an emergency alert the SES said that levees around Murrabit West were failing, warning that the area would be inundated in the next 12 hours.
"They are being flooded now," Monk told AFP. "It`s across properties. If they haven`t sandbagged them, there may be some impacts on people`s housing."
The Victoria floods stem from La Nina-provoked torrential rains which hit the state mid-January and followed weeks of widespread floods to the north that killed at least 30 people and devastated mining and farming in Queensland.
Prime Minister Julia Gillard again called on companies to boost their donations to the rebuilding effort, with infrastructure repairs and help for businesses and families estimated to cost some Aus$20 billion ($19.8 billion).
Champion American cyclist Lance Armstrong, who has been in Australia for the Tour Down Under in Adelaide, did his part, leading some 2,500 people on a Queensland Ride Relief fundraiser around Brisbane.
The seven-time Tour de France winner praised Queenslanders for the way they had rallied after the disaster, saying he had heard that so many people had driven into Brisbane to help clean up they caused traffic jams.
"You know what that is? That`s a whole lot of heroes the whole world needs to pay attention to and copy that," he said.
"I can tell you, having lived in the United States and having watched (Hurricane) Katrina closely, there were no traffic jams going into New Orleans. So for you guys to step up like that, is unbelievable."
As Queensland begins the massive recovery phase, Victoria is dealing with a record-breaking deluge which has so far affected more than 1,700 properties in the rural northwest of the state.
Emergency officials have been preparing for potential flooding along the Murray River -- a vital lifeline in the southeast which had been hard hit by a recent protracted drought -- since record rainfalls in mid-January.
The regional centre of Swan Hill, with a population of about 10,000, was bracing for floodwaters to peak on Thursday or Friday with residents frantically sandbagging but officials expecting the levee to hold.