Officials describe the flood situation in southern and central Queensland, as dire.
Some areas are experiencing their worst floods in decades.
Acting Premier Paul Lucas says the damage bill is likely to exceed $A1 billion.
"Early estimates of the cost of replacing essential public assets is close to $A620 million," he said in a statement.
Disaster areas have been declared in Theodore, Chinchilla and Dalby, as well as in Alpha and Jericho.
The flood in Dalby the worst since 1981. The ABC reports the town is split in two with at least 100 houses inundated.
About 120 residents have had to seek shelter in the town's two evacuation centres.
The ABC reports flooding is expected to peak in Emerald and Rockhampton in the coming days.
There could also be evacuations in the next 24 hours in Bundaberg.
The weather bureau says Rockhampton on the Fitzroy River should see a flood of 8 metres this week, with the potential for a major flood level of 8.5 metres next week.
Mayor Brad Carter says that if the river reaches 8.5 metres, more than 400 homes will be affected.
Two RAAF Blackhawk helicopters will be used to evacuate remaining residents in the town of Theodore, after the Dawson River burst its banks and inundated the area.
The Dawson River has hit a record 14.59 metres there, more than half a metre higher than the previous record.
The Bureau of Meteorology says there will be further flooding as the water makes its way towards the sea.
Almost 50 areas in North South Wales have now been declared natural disaster zones because of the flooding there.
The latest is Kyogleshire, on the north coast of the state, which was inundated on Tuesday after heavy rain.
More than 100 people there had to leave their homes.
The Richmond River has peaked at more than 16 metres high.
NSW Emergency Services Minister Steve Whan says disaster declarations are very effective in helping to assist councils with rebuilding infrastructure when the waters subside.