Higher-than-expected coal royalties have bumped Queensland's annual budget surplus up by about $1 billion more than predicted six months ago, Treasurer Jackie Trad says.
The State Government had predicted a net surplus of $485 million for 2017/18 in December, but on Tuesday morning Ms Trad said it was now "three times" that amount.
"The coal price has remained quite high, so that has meant increased royalties back to the State Government," Ms Trad told ABC Radio Brisbane.
"Also we have seen increased dividends from our government-owned corporations, which is a good thing.
"This is what happens when you keep income-generating assets in public hands — they return money back to the public so we can get on and do things like build hospitals and provide education services."
Ms Trad also credited an increase in national GST returns with helping bolster the surplus.
The budget will be officially released at 2:00pm.
'Borrow to build' budget
The State Government has promised a $45 billion infrastructure spend over the next four years, and Ms Trad said $11 billion of that would be spent during 2018/19.
That included investments in Brisbane's Cross River Rail and upgrades to the M1 and Bruce Highway.
State debt is forecast to rise to $83 billion by 2022, with Ms Trad saying about half of that would be government sector debt, with the rest carried by government-owned corporations.
"This debt that we accrue goes into building the infrastructure that we need," she said.
"Our debt is stable, it's absolutely sustainable, but more than that it's actually going into growing our economy and growing jobs."
Fifty-seven schools are also set to receive extra classrooms as part of a $250 million investment over two years.
New waste levy fund
The Queensland Government has also said it was setting aside $100 million in revenue from the incoming waste levy in the budget to try and move towards a European model of turning waste into energy.
The new fund will be available to private companies and local governments to come up with new and environmentally friendly ways to deal with mounting levels of waste.
The waste levy begins in January, 2019 at $70 per tonne for dumping general waste to landfill, aimed at curbing the transport of waste to Queensland from interstate.
Almost 40 affected councils have been promised advance payments to offset the cost of the levy in the initial years and prevent it from being passed on to ratepayers.
Surplus revenue from the levy will be rolled out as grants of up to $5 million on a dollar-for-dollar basis to encourage the construction of new large-scale facilities and infrastructure.
