Australia's flood crisis deepened Saturday with a giant "inland sea" threatening more communities in the southeast, as officials continued the grim search for bodies in worst-hit Queensland.

Sandbagging was underway in some villages in Victoria, where weeks of floods have affected as much as one-third of the state, with swollen rivers overflowing in 75 towns and flooding some 1,770 properties.

"We know that this is the most significant flooding in the north west of Victoria since records began... about 130 years ago," a spokeswoman for the State Emergency Service told AFP.

"We are still on alert for towns in the north of the state."

Floodwaters which national broadcaster ABC described as a moving "inland sea" covering an area 90 kilometres (56 miles) long and 40 kilometres wide, were threatening towns around Swan Hill, some 300 kilometres northwest of Melbourne.

"In the actual Swan Hill township itself, we are very confident that the levee system around the town is built to a very high grade and will protect the township," Mayor Greg Cruickshank told ABC radio.

But rural and outlying areas "will have significant amount of inundation through them," he said.

While thousands of people around the state have been urged to evacuate, emergency services warned that those people who choose to remain on their properties in the rural areas could be stranded by the floods.

"A number of these communities will be isolated for days as this huge amount of floodwater comes through," SES spokesman Kevin Monk said.

Eastern Australia has been lashed by torrential rains triggered by La Nina, a weather system associated with cyclones, which caused massive floods that devastated Queensland and spread south to New South Wales.

After surging torrents of dirty brown water flooded an area the size of France and Germany combined in Queensland -- killing more than 30 people and leaving a massive trail of destruction -- more floods developed in Victoria.

As the recovery and clean-up continues in Queensland, hundreds continued the search for the missing from violent flash floods which swept houses and cars into churning waters in the Lockyer Valley west of Brisbane.

Nine people are still missing after the floods which tore through towns such as Toowoomba and Grantham on January 10.

About 400 police were involved in search and clean-up efforts on Saturday and Ipswich Mayor Paul Pisasale said the strain of the extended crisis was telling.

"I think people are tired now, they're fragile and there's a lot of issues in regards money and support," he told ABC.

The floods which shut down Brisbane, the country's third largest city, also dumped tonnes of debris -- including cars, parts of buildings, and boats -- into the Brisbane River which the navy was Saturday working to clear.

As the waters recede in many areas of Queensland, the 75,000-strong city of Rockhampton, which was almost entirely isolated by floods earlier this month, is expected to soon have its air link back.

Some three weeks after Rockhampton airport's runway disappeared under water, daytime flights will resume on Monday after all major repairs and fencing work has been completed, officials said.

But the floodwaters are expected to remain in much of Victoria for days.

"We are still experiencing river peaks so that's going to obviously increase the amount of time," the SES spokeswoman said. "But in low-lying areas where there is flood waters, they can hang around for weeks."

Source - Yahoo.