It's "extraordinarily surprising" no one was killed during Cyclone Debbie or its torrential aftermath, Queensland's emergency services chief says.
The category 4 winds and rain that blasted the state's northern coastline are now wreaking havoc inland and to the south with almost almost 500mm falling in 24 hours near the Gold Coast.
About 90 people trapped on top of houses, cars and verandahs as a result of rising floodwaters just west of cyclone-battered Mackay were rescued on Thursday morning.
Queensland Fire and Emergency Services commissioner Katarina Carroll said there were 50 rescue call-outs around Mackay during a hectic and tense Wednesday night.
Ms Carroll said she was stunned there had been no lives lost or significant injuries.
"Extraordinarily surprising but you know, I think the community has been listening (to warnings)," she told the Nine Network.
"The difficulty with last night was you couldn't see. It was dark but also the conditions were horrendous, we couldn't move.
"In two-storey houses there was water actually buffeting of the second storey, so there was an extraordinary spike in the triple-0 calls."
Flooding on Wednesday night and Thursday morning was at its worst southwest of Mackay where the Pioneer River broke its banks, inundating local dams especially in the Eton and Homebush areas.
Ms Carroll said 46 people were rescued during the night and 40 more were evacuated before 10am on Thursday.
"We did have people up on the top level of their houses, reports of people on the roofs of their houses and roofs of their cars," she said.
The Bureau of Meteorology confirmed major flood warnings for several central Queensland towns but said the Pioneer River in Mackay was "an easing situation" as the weather improved on Thursday afternoon.
Between 400-800mm of rain fell in Mackay over the previous three days, forcing residents downstream of the Kinchant and Middle Creek Dams to move to higher ground.
Mayor Greg Williamson said the city had less than 24 hours of safe water supply left.
Clean-up efforts in the towns hardest hit by the cyclone, Bowen, Proserpine and Airlie Beach, have been hampered in recent days as floodwaters blocked roads.
About 58,000 homes and businesses have been without power since Tuesday, with Ergon Energy unable to access the towns to start repairs.
Thousands of residents are also without running water.
Emergency services crews and the army managed to make their way south to Bowen and Proserpine on Thursday, with fire and rescue teams expected in Airlie Beach on Friday.
About 20 soldiers from the 3rd Brigade at Townsville's Lavarack Barracks will stay in Proserpine over the coming days to assess the damage, with the troops from Bowen on stand-by to help with the clean-up.
Major Paul Cosgrove told AAP the soldiers were "desperate to get amongst the people" and help.
"Our troops are available as and when we get requested by the council," he said on Thursday.
Visiting Bowen on Thursday morning, Prime Minister Malcolm Turnbull and Opposition Leader Bill Shorten announced financial aid would be immediately available to start rebuilding infrastructure.
"Nature flings its worst at Australians and it's certainly happened here in the Whitsunday region but it brings out the best," Mr Turnbull told reporters.
Disaster assistance including concessional loans is starting to flow to primary producers after the cyclone tore up sugar cane and vegetable crops and hit the beef cattle industry. However, recovery work has also been hampered by flooded roads.
Hundreds of tourists and residents stranded on Hamilton Island are still to be flown to safety while all on Daydream Island have been evacuated but the resort will be closed for a month .
