Flood warnings issued as thousands of residents evacuated their homes in the town of Wagga Wagga [Reuters]

Emergency services have ordered more than 8,000 people to evacuate a New South Wales town, in southeast Australia, threatened by rising floodwaters.

New South Wales emergency officials and police ordered thousands to evacuate the centre of the town of Wagga Wagga on Tuesday as the Murrumbidgee river threatened to breach the town's levee barriers.

People had already been ordered to evacuate homes in the surrounding area after the river burst its banks in places.

On Sunday, about 13,000 people around New South Wales were also asked to leave their homes due to the flooding.

'Significant risk'

Floods hit three eastern states this week, sweeping two men to their deaths after they attempted to cross waterways in cars.

The rising rain waters inundated more than 250 properties and isolated a number of rural communities causing millions of dollars in damage.

Julia Gillard, the Australian prime minister, said earlier that the military had been deployed to several areas and was on standby to help other stricken towns if the crisis deepened.

Across the state more than 13,000 people have been ordered from their homes because of flooding [EPA]

"We've got floodwaters across New South Wales, Queensland and Victoria," she told reporters.

"For the people of Wagga particularly, this is a very anxious time."

"There is a significant risk that the levee will overtop or potentially breach," said Andrew Richards, the New South Wales State Emergency Service (SES) spokesperson.

Meanwhile, however, SES issued an "all clear" for Jugiong township, east of Wagga Wagga. SES said on their website that it was safe for residents and business owners to return and re-enter their properties.

SES also announced on Tuesday the reopening of the Yarramundi Bridge and the Webbs Creek, Wisemans Ferry, Lower Portland Ferries, but said that the Sackville Ferry would remain closed.

Richards said while the levee was so far working to protect the commercial centre of Wagga Wagga, across the river in North Wagga Wagga many of the homes from which 600 people have been evacuated had probably been swamped.

"The reports we are getting from Wagga are that a significant number of homes in that area have been affected," Richards told the AFP news agency as the river rushed towards a level not seen since 1844.

Wagga Wagga has been hit by several significant floods since the earliest European settlement in the 1840s, and officials said residents had responded well to the latest evacuation order.

"I knew where my house lies, if the levee were to overflow my street, it was pretty quickly going to go, so I went," Melina Skidmore told state broadcaster ABC.

Flooding has also hit rural regions in Victoria and Queensland states.

The National Farmers' Federation said while it was too early to estimate losses, cotton crops had been damaged, as well as grain silos, while many livestock had been swept away.

Eastern Australia was hit by devastating floods in early 2011 which claimed more than 30 lives, flooded thousands of homes and left vast swathes of the country swamped, including the Queensland capital Brisbane.