Authorities have told residents to flee their homes and take three days of supplies, before floodwaters breach levees in the latest community swamped during Australia's flood crisis.
Up to 1,500 homes in Kerang, in the north of Victoria state, could be affected if the Lodden River rises any further.
It follows weeks of massive flooding in northeastern Queensland, which left two-thirds of the giant state underwater and 30 people dead.
The Kerang levee has breached at several points and the State Emergency Services is urging townspeople to head for a relief centre on higher ground.
Walls of water miles wide are surging across northern and western Victoria in the wake of record rainfall last week.
Floodwaters have already left 1,000 households in Victoria's northwest without power, and thousands more homes are under threat of cuts as substations and low-lying power lines are submerged.
In Brisbane, Australian Foreign Minister Kevin Rudd was joined by visiting British Foreign Secretary William Hague and Queensland state Premier Anna Bligh as they helped cook a breakfast barbecue for flood victims and clean-up volunteers.
Hague paid tribute to flood victims and volunteers and said Britain will do all it can to help.
"I just want to say that in Britain we admire your fortitude and resilience in what you've been through and we were with you in spirit all the way throughout it," he said.
The Australian government has said the Queensland floods could be the country's most expensive natural disaster ever.
The price tag from the relentless floods already stood at $5 billion before muddy brown waters swamped Brisbane last week.
