The rising tides cut off tens of thousands of people, forcing some to clamber atop cars, houses and highway bridges before helicopters winched them away.
Rescue crews have plucked more than 600 people to safety since the waters started rising earlier this week.
State Emergency Service head Dallas Burnes warned that even as the floods recede, the stagnant, muddy lakes still poses a threat, including from snakes that may have slithered into homes.
“Floodwaters have contaminants. There can be vermin, snakes. You need to assess those risks.
“Electricity can also pose a danger as well.”
He said recovery efforts were focused on “resupplying the isolated communities”.
-‘Horrific’ circumstances –
As he travelled into the disaster zone on Friday, Prime Minister Anthony Albanese described the situation as “horrific”.
“The Australian Defence Force will be made available. There’s going to be a big recovery effort required,” he told local radio.
“There’s been massive damage to infrastructure and we’re going to have to all really pitch in.”
The government has declared the floods a natural disaster, unlocking greater resources for affected areas.