Queensland's southern interior remains on edge as river systems continue to rise with flood warnings in place for the Mary, Condamine, Balonne, Thompson and Cooper river and creek catchments.

The unseasonal May rainfall inundated homes and businesses, with roads and bridges swamped across the state.

One woman was killed when a car was submerged in floodwaters near Mackay on Wednesday. She was still wearing her seatbelt when her body was found.

Another two people remain unaccounted for as police scour the Brisbane River for a man last seen on Sunday while a second man is missing near Stanthorpe.

Keiran Wilson, 26, was last seen around 9am Friday, May 13 driving away from his Ballandean home during the flooding.

As the rain event eased, the focus on Monday shifted to recovery efforts in the Lockyer Valley where Laidley's main street and surrounding farmland were swamped by floodwater.

While the immediate cost of repair is still being counted, Australians have been warned the price of fresh fruit and vegetables will increase in the wake of the disaster.

Farmers who risked planting after the February deluge lost entire crops and face financial ruin after the second deluge.

Lockyer Valley mayor Tanya Milligan said crops were rotting in the ground and 90 per cent of insurance claims have been rejected.

"A lot of those farmers were hoping and depending on that (insurance payout)," Cr Milligan said.

"We will have farmers that have no intention to replant. You have people that have just lost absolutely everything and they will be wondering is it all worth it?

"That is a huge concern and I don't know how quickly they will recover. I don't know what that will mean for us as a state, as a nation ... for every mum and dad and a couple of kids wanting to buy their produce from the supermarket."

For a community that has battled years of drought and now floods, Cr Milligan said the strain had taken a toll as exhausted locals tackle yet another major clean up.

"The last few days have been very at times, gut-wrenching, soul-destroying and quite emotional," Cr Milligan told reporters.

"I think it would be fair for me to say and I need to say it as mayor, that we're a bit fatigued.

"Whilst the waters have subsided ... I really believe that it's the emotional side of things and the build back and the cleanup - I think, I think that's the really tough stuff."

Police Minister Mark Ryan said the state government would work with the community to repair and rebuild.

"There have been a number of businesses and residents impacted in this region and it breaks your heart to see that people are impacted to the extent that they are," Mr Ryan said.

"Whilst you can always rebuild, it's the emotional toll that disasters like this have on people's lives.

"I wanted to reinforce to everyone that, you know, the authorities, the council's the state government, the federal government, we all work together here to support people in the recovery effort."

While the upper trough that triggered the deluge has moved offshore, light showers will hang around during the week before another weather system develops on Friday.

Australian Associated Press