RICHMOND: Flood-stricken residents along Australia's east coast began a massive clean up effort on Thursday as waters receded, revealing damaged homes, piles of debris and mud-caked roads.

The region has been devastated by widespread flooding brought on by a torrential downpour that inundated towns, destroyed farmland and left two people dead.

With the rain clouds finally clearing to reveal blue skies, thousands of people in Australia's most populous state New South Wales returned to their homes to assess the damage.

Hundreds of troops and volunteer firefighters bolstered efforts in stretched communities, digging mud from roads and using chainsaws to clear debris from properties.

Ben Shepherd, an inspector from the Rural Fire Service, said the teams wanted "to try and return communities to some sense of normality as soon as possible".

"This is going to be a prolonged event that is potentially going to take weeks -- if not months -- in some areas," he told AFP.

Across the vast flood zone, many communities remain cut off by swollen rivers and it was still unsafe for about 20,000 people to return home.

Authorities pleaded with residents to remain vigilant around floodwaters.

"We believe that most river systems have peaked but complacency is a concern for us," state Premier Gladys Berejiklian said.

"Unpredictable flows will continue to occur in communities which haven't seen this amount of rainfall for up to 50 or 100 years."