Townsville residents have begun the massive cleanup after more than a week of record flooding inundated thousands of homes and claimed the lives of two people.

While hundreds of people remain holed up in evacuation centres across the city, waiting for floodwaters to recede, others have returned to find their homes devastated and their treasured belongings washed away.

The Bureau of Meteorology warns the one-in-100-year monsoonal deluge is far from over for North Queensland, with more heavy rain likely from Palm Island, north of Townsville, south to Mackay on Wednesday.

Household belongings lined front yards in Townsville and cars were strewn about the streets as the waters receded and revealed the extent of the damage.

Queensland Fire and Emergency Services Commissioner Katarina Carroll says it is impossible to know how many homes have gone under across north Queensland already.

“It’s easily hundreds, it could be thousands,” she said, but added audit teams were being hampered by the enduring risk of flash floods with each new deluge.

The ongoing severe weather warning follows the discovery of two men’s bodies in a Townsville drain after floodwater receded.

An investigation has been launched into the conduct of police officers in the lead-up to the deaths of Troy Mathieson, 23, and Hughie Morton, 21.

The Ethical Standards Command will investigate the police who had been searching for the men after an attempted break-in at a nearby Dan Murphy’s liquor store at 3am on Monday.

A local resident said the men may have been sucked into man-sized pipes that lead to the drain from the store where a looting incident had been reported.

The tragic news came as residents cautiously contemplated their losses and the massive mop-up operation ahead.

Gwen Cooms, from the small community of Balgal Beach, around 50 kilometres north-east of Townsville, said she was caught by surprise when a she woke Monday night to water swirling at her front door.

Ms Cooms told the ABC that while she was insured, some belongings could not be replaced.

“A washing machine and a dryer probably, you can buy that again can’t you?” she said. “But the thing I worry about is photos that you can’t replace.” 

Clayton and Carmel Linning returned to their s house in the Townsville suburb of Idalia to find it dark, musty and and smelling of petrol.

“Just coming up the driveway, looking at all the mud, that’s when it hit home,” Mr Linning told ABC.

“As soon as we opened the door it was a bit sad, but you have to deal with it, I guess,” he said.

“Just seeing some of the houses in this area, there’s a lot of water that’s come through here, a lot of water.”

The 12-day-old weather event has exhausted emergency service workers, who have carried out thousands of rescues since the flood crisis began.

More than 100 fresh police officers and nurses will begin flying into Townsville to relieve their local colleagues on Wednesday.

Their arrival comes as schools in the region begin reopening as the monsoon trough slowly pushes south.

The vigorous weather system has delivered disaster to Townsville and generated floods out west, with farmers around Cloncurry, McKinlay and Flinders shire reporting livestock losses.

Major flood warnings also remain in place for the Ross, Haughton, Upper Burdekin, Flinders, Cloncurry and Leichhardt rivers.

An emergency alert was issued for Hughenden with the Flinders River expected to cause flooding on the north side.

-with AAP