Piles of rubbish in the Lismore CBD. Picture: Nathan Edwards

Stinking mud, piles of debris and damage bills fast approaching the millions, and possibly hitting one billion dollars are the next wave of misery from Cyclone Debbie as the massive and costly clean-up continues.

Meanwhile, a desperate search is underway for a mother and at least one of her children after a car plunged into the flood-swollen Tweed River in northern NSW.

Rockhampton is a city playing a terrible waiting game, as floodwaters creep closer, expected to peak at nine metres on Wednesday morning.

The airport is closed, residents in low-lying areas are sandbagging, and flood modelling shows the water is expected to march into the central business district.

The city is bracing for the worst, and not just in terms of natural disaster: police plan to be patrolling from the sky as the waters rise in a bid to prevent looting in the central Queensland city, the Courier Mail reports.

A PolAir helicopter will assist “with prevention of crime, flying over the flood effected to ensure that we’ve got no offences getting committed there”, Superintendent Ron Van Saane said.

It came as Lismore police arrested one man for theft and intimidation and moved on 16 other people from the Lismore CBD over the past 24 hours as a result of reports of looting in the township, the Northern Star reports.

‘NOT OUT OF THE WOODS’

Flooding forecast for Rockhampton is not as bad as first thought, but with a huge volume of water still slowly spilling down river systems, it’s next in the firing line.

It was initially feared Rocky would be hit later this week with the worst flooding in more than 60 years, but the estimated peak had now been revised down, from 9.4 metres to 9 metres.

Major flood warnings still exist for the Firzroy River, with flooding expected to affect more than 2000 homes and 1200 commercial properties.

Rockhampton Mayor Margaret Strelow says the city is prepared, but the effect on Rockhampton, including to its economy, would be vast.

She expects about 400 homes to have water over the floorboards, but says many, many more will have water under properties, and there are concerns for critical infrastructure including roads.

It’s thought 120 commercial properties will also have some water through them.

“We do want to stress to the people of Rockhampton that you still need to make your flood preparations,” said Queensland Premier Annastacia Palaszczuk. “We are not out of the woods yet, there is still a long way to go.”

Extra emergency crews sent to the town for flood preparations. “Although this is a slow moving lead-up to the floods, the reality is we need people to be moving and taking action right now,” Queensland Fire and Emergency Services deputy commissioner Mark Roche said.

Residents are moving livestock, preparing shops and the airport with sandbags as the waters rise.

SES members sandbag a levee to protect the airport buildings and infrastructure in Rockhampton. Source: 9 NewsSource:Channel 9

Rockhampton airport closed at midday Monday, and will be closed for at least the rest of the week with water expected to be over the runway by Monday afternoon.

“HEARTBREAKING” MESS, RESCUE VIDEO

Floodwaters are receding in northern NSW and southeast Queensland as residents and business owners return to thick, stinking mud, piles of debris and ruined property.

“It’s pretty devastating to see piles of rubbish above your head and 10 to 20 metres wide. It’s heartbreaking,” Lismore Mayor Isaac Smith told AAP.

As the extent of flooding, which has left more than 11,000 people displaced from their homes from northern NSW to southeast Queensland, was hitting home, video emerged of a Gold Coast home being swept away by raging floodwaters, just minutes after a family was plucked from its roof by rescuers.

The footage shows the home knocking down trees in its path as it is lifted from its foundations, and carried away.

Just 15 minutes before, a mother and two children had been able to signal SES workers for help.

Salvation came for them, another man, and two dogs who were inside the home after they had waited on the roof for hours in darkness, ABC reports.

The house being swept away by flood waters. Picture: ABCSource:ABC

The rescue came on Saturday morning in a street of Luscombe after the flooded Albert River swept through the streets.

“It took us approximately an hour to dodge the high trees, the powerlines, the stuff that was coming down the river,” disaster management officer Jim Ferguson said.

“I climbed over the balcony hands and knees along the awning, stood up and made my first real contact with the parent and the two kids.”

The mammoth clean-up begins in Lismore. Picture: Nathan EdwardsSource:News Corp Australia

SNAKES, RATS AND SPIDERS

And as the clean-up continued, the SES warned those that are returning to their homes to be wary of “unexpected visitors” in the form of snakes, rats, spiders and other vermin who might have taken up residence, ferried by floodwaters.

“If people have been affected by flooding, there are a number of hazards that can occur. These can include contaminated mud which could have traces of sewage or chemicals. There may be snakes, rats, spiders, and other wildlife that may have taken refuge in the property,” said SES spokesman Phil Campbell.

While the worst of the weather is over, the daunting task facing those affected is just beginning.

NSW State Emergency Services Deputy Commissioner Mark Morrow said it would be a long haul for towns such as Lismore and Murwillumbah that were inundated by floods.

Devastation: A Lismore carpark became a sea as floodwaters rose. Picture: Nigel HallettSource:News Corp Australia

“The mud, combination of chemicals, raw sewage, paint which gets into everything. Two to three metres above floor level. Nothing escaped this. It was a very, very big flood,” he said.

Many of those who fled the area have begun heading back, with Mr Morrow warning “it won’t be pleasant.”

Military and emergency personnel continued to work to restore essential services such as water and electricity in affected towns, where hundreds of homes have been deemed uninhabitable.

LISMORE’S HEARTBREAK

Lismore residents have returned to a deluge of rubbish and muck.

Mayor Isaac Smith said about 3000 homes and businesses in the town centre had been damaged by floodwaters, which reached near-record levels.

The Rural Fire Service has set up a base camp for hundreds of workers, including nearly 400 SES volunteers, who will work on the clean-up.

“It’s a massive job. It will take a lot of co-ordination and, really, things we haven’t done on this scale before,” Mr Smith said.

Food trucks and petrol tankers have started bringing in supplies after the roads were cut for days.

The Wilsons River, which flows through the town, peaked at 11.6 metres on Friday — its highest since 1974.

The deluge began at 4am that morning when a siren was sounded for the first time in 12 years as heavy rain from ex-tropical Cyclone Debbie moved in and caused the levee to break its bank.

Mr Smith said the mood in Lismore remains positive despite a few reports of minor looting.

“Most things are flood affected anyway, so there’s not much worth stealing,” he said.

“The town is coming together.” But there are some outstanding dangers, like the risks posed by contaminated water.

The town’s sewerage network is expected to return to operation on Monday. Meanwhile, residents further north in Murwillumbah are also coming to terms with flood damage as their mop-up continues.

Staff clean the rooms of the Lismore City Motor Inn in the flood ravaged centre of Lismore. Picture: AAP/Tracey NearmySource:AAP

INSURANCE COMPANIES ON NOTICE

The Insurance Council of Australia (ICA) has estimated the damage bill could reach $1 billion.

NSW Premier Gladys Berejiklian, assessing the damage in the Tweed Heads area, said the bill for the worst floods in NSW in 40 years is already in the millions, and will rise.

And she bluntly warned insurance companies they are “on notice”.

“No-one is to drag their feet,” she said. “They’ll be answerable to me. They’ll be answerable to every person in the community. We want people to be treated fairly.

“Millions have been spent supporting the effort in the last three days,” she told reporters in Banora Point. “There will absolutely be more to come.”

These Hertz hire vans were tossed into a creek and up a tree as floodwaters hit Lismore. Picture: AAP/Tracey NearmySource:AAP

“It is not just about the few days when the floods hit and the water recedes. This is when the work starts. We know that,” she said.

The ICA’s Campbell Fuller said “The Insurance Council of Australia reassures Premier Berejiklian that the industry is doing all it can to anticipate and respond to the needs of affected policyholders.”

In Lismore alone, more than 500 SES volunteers in addition to another 500 personnel from other agencies are on hand to assist residents in the clean-up.

John Monk looks at his boat which is still tied to the veranda of his house where cars and banana trees are washed up alongside on the Tweed River in Murwillumbah, New South Wales. Picture: AAP/Tracey NearmySource:AAP

PM FLIES IN

Prime Minister Malcolm Turnbull says the government will offer “enormous support” to flood- affected communities. “We have seen nature flinging her worst at Australians, but it always brings out the best in Australians,” he said.

Mr Turnbull was in Lismore’s CBD, which on Friday was under several metres of floodwater after the Wilsons River topped the town’s levee bank. He reassured residents and business owners, who are beginning the clean-up, they would be supported.

He said it was “gut wrenching stuff” to see first hand the flood damage.

On Friday the federal and NSW governments announced that disaster assistance was available for the northern NSW communities affected by flooding,” he said.

Flood levels in Lismore peaked within a metre of the 1974 record of 12.2 metres on Friday, busting over the city’s $19 million levee, built in 2005 to withstand a one in 10-year flood.

Prime Minister Malcolm Turnbull passes piles of debris in the Lismore CBD. Picture: Nathan EdwardsSource:News Corp Australia

Meanwhile, in the worst hit areas which Cyclone Debbie hit — Airlie Beach and the Whitsunday — many resorts face months of repairs and rebuilding, but despite this tour boats mostly survived and some are already back in business.