Tragedy has struck in flood-ravaged southeast Queensland with a missing 77-year-old man found dead.
As floodwaters threatened hundreds of properties in Logan, the body of Eagleby man Nelson Raebel was found by emergency crews on Saturday afternoon, becoming the state's first victim following ex-tropical cyclone Debbie.
Police said Mr Raebel was found not far from where he was last seen near Eagelby Road on Friday afternoon.
Three others are still missing, including 50-year-old Mondure man David Heidemann and a man in his 60s who went bushwalking at Lamington National Park.
A fourth person is missing in cyclone-battered Mackay.
On Saturday, the Logan River experienced its biggest river peak in 43 years, matching 1974 levels when it reached 10 metres at Waterford, Logan about 1.40pm on Saturday.
While it still fell short of a predicted 10.5-metre peak, authorities are still forecasting floodwaters to inundate 300 plus properties, including about 200 homes.
This includes those already inundated from the city's other swollen river, the Albert River, which peaked on Friday.
Logan mayor Luke Smith warns that the danger is not over as it will take the Logan River some time to subside.
"It will stay (at 10 metres) for the next 12 hours before gradually receding," he told AAP.
He said he was disappointed to see many people rubbernecking around the Larry Storey Park and bridge at Waterford at the time of the peak.
"There were people everywhere. It was crazy," he said.
"We had to get our park rangers to move people on, police had to get people to keep on driving because they were stopping and causing congestion."
The Logan River is yet to peak at Eagleby, which is expected some time on Saturday night.
Eagleby - where the Albert and Logan rivers meet - and nearby suburbs including Loganholme and Beenleigh are the most vulnerable areas.
On Saturday morning, police rescued an elderly man from public toilets at a flooded park, after the river rose to near-record levels.
The man was pushed through fast-moving, ankle-deep water by two officers at Tygum Park as about 20 people who had come to inspect the floods looked on.
It came after swift water rescue workers helped three women and two babies escape floodwaters at Waterford West on Saturday morning.
For others, like Waterford resident Tony McCorry, the flooding meant hopping in a canoe for a paddle around what was his backyard.
Those in other parts of Logan spent the day busily scrubbing away silt and clumps of debris swept into their home and yards from floodwaters on Friday.
Before buying a three-bedroom house in Logan, Ashleigh McGrogan was told there was only a one per cent chance it would flood.
Four months after she and her husband Adam moved into the three-bedroom house, they will have to replace all the flooring after the nearby creek overflowed and swamped their home.
Further south, the destructive floodwaters have claimed the lives of two women in NSW and resulted in emergency services workers rescuing hundreds.
