01/04/2017 7:31 AM AEDT | Updated 02/04/2017 1:35 PM AEST

Flood Threat Shifts To Rockhampton As Crisis Continues In NSW And Queensland

The floods have so far claimed the lives of three people.

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Locals paddle down the main street of Billinudgel in NSW.

Queensland Premier Annastacia Palaszczuk has reassured flood-hit residents that the state government will help them to "get back on their feet" as authorities shift their focus to Rockhampton ahead of a potentially record-breaking flood this week.

Rockhampton is predicted to be the next area set to suffer the fallout from ex-Tropical Cyclone Debbie, with the Fitzroy River predicted to peak at 9.4 metres on Wednesday.

"The main flood peak in the Fitzroy system is now in the Mackenzie River downstream of Coolmaringa and will move downstream over the next week," BoM said on Sunday.

Hundreds of people are likely to evacuate and the airport is likely to shut on Monday when the Fitzroy River is predicted to rise to 8.7 metres.

Meanwhile, the cleanup is underway at Logan in the state's southeast as well as parts of Beudesert and the northern Gold Coast which copped the brunt of Debbie's aftermath over the weekend.

Speaking in Logan, Palaszczuk said authorities were working as fast as possible to assist flood-impacted residents.

"No matter where you are across this state my government is here to assist you, the councils are here to assist you and we will work collaboratively together to get you and your family back on your feet," she told reporters.

So far, three people have died in the flood emergency that has engulfed northern NSW and southeast Queensland.

The latest confirmed fatality was a 77-year-old man whose body was found at Eagleby, south of Brisbane, on Saturday.

On Friday, a woman's body was found on a flooded residence near Murwillumbah, while a 64-year-old woman died in the Hunter region after her car was washed off a causeway near Muswellbrook.

Authorities are still looking for three people still missing in flood-impacted parts of Queensland.

In NSW, flood waters are receding at Lismore, one of the worst affected towns in NSW, and thousands of residents are returning to the town.

Water levels are also falling at the flood-hit town of Murwillumbah.

While conditions have improved, dangers remain and the NSW State Emergency Service (SES) is said to have turned away some people returning to the area while experts assess the risks.

NSW Premier Gladys Berejiklian will head to the flood impacted areas on Monday to get a first-hand look at the devastation that has been wrought in the state's north.

Prime Minister Malcolm Turnbull has cautioned people about entering flood waters.

"I want to say to everybody who is affected by these floods, do not go into flooded waters, do not cross flooded roads, follow the advice of the local authorities they know what they are doing, they will keep you safe," Turnbull said on Saturday.