Up to 50 people have been rescued after they were stuck on a bridge in northern NSW overnight with thousands more homes predicted to go under in the record-breaking flood event.
The Richmond River at Woodburn was at 6.3 metres and rising when those stuck on the bridge were rescued this morning.
"We had no capabilities to get them off in the dark so we just had to make sure that they bunkered down and we went in this morning and got them all out," Woodburn State Emergency Services (SES) Unit Commander Ashley Slapp said.
Mr Slapp said it is a "devastating" situation for the town, as hundreds of people shelter in the local public school.
"The capabilities of rescues have increased dramatically today, we have helicopters picking people up off roofs."
Rescues also resumed elsewhere after efforts were stalled yesterday due to dangerous conditions fuelled by hanging power lines and surging torrents of water.
LIVE COVERAGE: Follow flood developments as they happen on the ABC's blogJosh Clarke from the SES said they were currently prioritising a "life-threatening" situation at Bungawalbin, where they were expecting to make nearly 50 rescues.
He said helicopters and boats are going to assist but it could take some time.
"Crews will be there but we have to actually get down there and check that there's no one in the roof cavity, and in some cases cut into the roof to make those rescues," he said.
Mr Clarke acknowledged people had been on their roofs for "close to 24 hours now" and assured them "help is on the way".
Despite the rescue efforts, NSW Emergency Services Minister Steph Cooke said "we must prepare for the possibility that lives have been lost" in the floods.
"Whilst I would love to think and I truly hope that we will not see any deaths from this event, I think that it is unrealistic that a disaster of this magnitude will mean that there are no lives lost," she said.
Premier Dominic Perrottet said the SES had carried out more than 1,000 rescues after receiving 6,000 calls for help so far.
Natural disaster declarations have been made for 17 local government areas (LGAs), opening financial support for residents in those areas.
The Premier said 40,000 people were currently subject to evacuation orders, and 300,000 people are affected by evacuation warnings.
"We will continue to do everything we can to get everybody to safety and to get these communities back on their feet as quickly as possible," Mr Perrottet said.
Terry O'Toole from McLeans Ridges said his son, his son's disabled step-son and their elderly neighbour have been stranded on top of a roof on Bungawalbin Whiporie Road since yesterday afternoon.
He said they are surrounded by floodwater.
"It's all around them. It looks pretty close to the roof," he told ABC Local Radio.
"Water's over the roofs (of other buildings). The sheds all gone, the cars gone.
Further east at Ballina, where an evacuation order for low-lying areas was issued this morning, the town's Mayor said council modelling was predicting a one-in-500-year flood.
"The water will move slowly, but all predictions, all flood modelling that staff have done, we are facing a one-in-500-year flood and that is a serious situation for Ballina," Sharon Cadwallader said.
The Wardell Bridge is under water, the Burns Point Ferry is closed and the SES believe up to 7,000 homes could be inundated.
Ballina resident Vicky Timmins said the water was "getting really deep and coming up really fast".
She evacuated her parents about 7am this morning.
"The texts started coming through at 2am and my parents started getting calls from the emergency line phoning their home line, so they were quite panicked being elderly," she said.
"A lot of elderly people have decided to stay which is really concerning for me."
Ms Timmins said with tidal flooding also common in the area, there are a lot of unknowns about the hours ahead.
"That's the problem, we still have another hour till high tide, it's concerning knowing it can get worse."
With the water lapping at their house in Ballina, Paris and Daniel Anderson decided to pack up and leave, taking their two small children to stay with relatives nearby.
"I just woke up this morning and I had missed calls and I looked out the front and it was just crazy," Ms Anderson said.
"It was just water everywhere, I had to wake him up and quickly tell him to hurry up to pack a few bags and let's go."
Further down the road, neighbour Sam Kennedy was planning to stay put.
"We got the text message from the SES saying we had an evacuation order," she said.
"It was a bit of a surprise but we have enough time to prepare.
Lismore's Wilsons River peaked at 14.4m yesterday afternoon, however, authorities warned it would be several days before the danger subsided.
Rain is expected to ease today, after a deluge yesterday saw areas like Rosebank, near Upper Coopers Creek (701mm) and Mullumbimby (520mm) inundated yesterday.
A severe weather warning is in place for heavy rain and high winds along the NSW coast from Newcastle to Bega, which could cause widespread damage and flooding.
The Bureau of Meteorology (BoM) said the severe weather was likely to begin this evening, and some areas could record up to 200mm of rain in a six-hour period.
Water has already been released from Warragamba Dam in anticipation of the weather.
