Rain is forecast to continue hammering already inundated regions across New South Wales and Queensland on Sunday as the clean-up continues across the two states.
The Bureau of Meteorology (BOM) warns areas of NSW stretching from the Hunter to the Central Tablelands and down the South Coast are in for more rain on Sunday, with thunderstorms and intense rainfall a possibility.
Western Sydney is also in line for heavy rain, with moderate to major flooding possibly returning in the Hawkesbury-Nepean valley.
The BOM has observed renewed rises and flooding along the Upper Nepean, Nepean, Hawkesbury and Colo Rivers, and warns that flooding there may reach levels similar to the past week.
Some areas could receive up to 120mm of rain in six hours and dangerous flash flooding could follow.
Meanwhile, Queensland police are urging residents to take care with more storms predicted across the southeast on Sunday.
"It is still quite saturated and we will expect flash flooding, so please be patient," Commissioner Katarina Carroll said on Sunday.
There is potential for severe storms in Bundaberg, Gympie, the Lockyer Valley, Brisbane and the Gold Coast with large hail, heavy rain and flash flooding possible, BOM said.
Each of the state's 11 flood related deaths were as a result of people going into flood waters, Ms Carroll said.
"Some definitely unintentional but certainly some people making really, really poor decisions," she said.
The death toll from the devastating floods across parts of Queensland and NSW stands at 17 after the discovery of a woman's body on the Gold Coast on Saturday.
State and federal leaders have promised more help and financial aid as some affected areas begin the long clean-up, while others remain underwater.
In Coraki, on the Richmond and Wilson Rivers south of Lismore in the Northern Rivers region of NSW, the local police station was one of many buildings inundated as the town was flooded and cut off from surrounding areas.
As waters recede, the damage is now being assessed.
NSW Police Coraki Sergeant Dean Childs says the town had little chance to prepare for the floods.
"It happened that quick and no one expected it to be that high," Sergeant Childs said.
With only a small number of emergency service personnel in Coraki, community members had to step in too.
"To have a flood this size and have the SES in such a small town, it's a smaller SES so we only have a certain number of boats, so we've got all these local people jumping in their own vessels to try and rescue people as well," Sergeant Childs said.
Community response to the disasters have drawn much praise while there has been criticism of government response and level of preparedness that required communities to rescue and look after one another.
NSW opposition emergency services spokesman Jihad Dib said on Sunday flood-hit communities are exhausted and people are now "at absolute breaking point".
"The local communities and people from outside of those local communities are doing all that they can, but they can't carry the full load by themselves," he said.
He said the state needs an overarching co-ordinator "to ensure that everything is managed in a very succinct and a proper way that places the community at the centre" and delivers the support and funding that has been announced.
Emergency Services and Resilience Minister Steph Cooke was named NSW Flood Recovery Minister on Friday.
Premier Dominic Perrottet on Saturday pledged his government would not "spare a dollar" in funding the recovery.
"After everything we've gone through as a state over the last few years I know we will get through this, as challenging as it seems," the premier said.
In Queensland Previous estimates have put the total damage bill at more than $1 billion including insurance claims and major infrastructure repair, and work is underway to establish the full financial impact.
"For an event that lasted just three days, it's going to have a big impact on our economy and on our budget," Treasurer Cameron Dick said on Sunday
There are still 140 people in flood evacuation centres and about 3,000 homes without power, most of which are expected to be restored by Sunday night.
Communities around Ipswich and Gympie are still isolated with roads expected to open on Monday.
"This has really packed a punch, these floods have had a big impact on people and it's going to take not just weeks but months for people to recover," Premier Annastacia Palaszczuk said on Sunday.
The state's $2.1 million donation includes $500,000 each to the Australian Red Cross, Lifeline, The Salvation Army and Vinnies, and another $100,000 to GIVIT.
Insurance claims from around the country had hit about $1.25 billion by the end of Friday, with the lion's share — $1 billion — being submitted from Queensland, industry body, the Insurance Council of Australia said.
Meanwhile, the federal government extended the number of local government areas able to access one-off disaster relief cash payments of up to $1,000 for adults.
"We continue to closely monitor the flood emergency and our hearts go out to those people whose lives are being devastated," federal Emergency Minister Bridget McKenzie said.
'Absolute devastation'
Defence Minister Peter Dutton has defended the response of the ADF in tackling the floods on the east coast of Australia, comparing the situation to that of a cyclone.
"It is much more than a flood that we are experiencing in northern New South Wales and the surrounding remote towns in particular," Mr Dutton told ABC's Insiders program on Sunday.

The ADF help clean up at the Rocklea Cold Storage facility, which lost more than $25 Million worth of food, in Brisbane on Saturday 5 March 2022. Source: AAP / Jono Searle
"The bravery exercised by these people, the work that they are doing on the ground is quite phenomenal," Mr Dutton said.
He said the number of ADF personnel will surge to 5,000 over the next few days and more will be supplied if needed.
"There has never been a question of the numbers of people, what we need on the ground," he said.
Labor's Defence spokesman Brendan O'Connor said there has been an enormous effort by emergency workers, professionals, volunteers, the ADF, private citizens who put their lives on the line to rescue others.
"I think people have really been quite remarkable," he told Sky News' Sunday Agenda program.
"But I do believe we should have had more mitigation investment in place before these terrible events."
He said a $4.8 billion emergency response fund was established three years ago, but not a cent had been spent yet on the construction of culverts, drainage systems, evacuation centres or anything like that.