The giant $5.4 billion Hells Gates Dam project has received guaranteed funding, unlocking the agriculture sector in some of the driest parts of northern Australia.
But the project remains subject to a business case expected in June this year, and other environmental approvals.
In a pre-election announcement during his blitz across Queensland this week, Prime Minister Scott Morrison said his government will guarantee the $5.4 billion required to construct the dam in its 2022-23 federal budget, due to be released next week.
But he said the timing of the dam's construction hinges on Queensland government approval.
The much-anticipated Hells Gates Dam project proposes a 2,100 gigalitre dam in the Upper Burdekin catchment, 120 kilometres north-west of Townsville in north Queensland.
The dam would be the largest in Queensland, opening up 60,000 hectares of irrigation across the region.
An 80-year old idea
It is a major step in a long-term plan to develop water infrastructure in northern Australia.
The 2,100-gigalitre dam in the Upper Burdekin catchment would be supported by three downstream irrigation weirs, including Big Rocks Weir.
The idea behind the Hells Gates Dam has existed for more than 80 years as part of the 1938 Bradfield Scheme.
A feasibility study by Townsville Enterprise Limited in 2017 confirmed Hells Gates is the best location for the dam.
Townsville Enterprise is conducting the final business case for Hells Gates.
Chief executive Claudia Brumme-Smith says it will also provide water security for north Queensland.
"Water is getting scarce and we need more infrastructure to catch the water as it falls in a different pattern over time," she said.
"This dam is actually the opportunity to not only sustain current water supply and security but actually grow it."
Federal government claims jobs boost
The federal government's funding announcement for Hells Gates comes a week after it declared it will contribute $483 million towards the construction of Urannah Dam, near Mackay.
The money promised is also subject to environmental approvals.
The federal government said construction of Hells Gates Dam is expected to create more than 7,000 jobs.
"This investment will kick off a jobs boom across north Queensland for years to come," Prime Minister Scott Morrison said.
The government claims ongoing operations and expanded agricultural opportunities will support 3,000 jobs, generating $6 billion of gross regional product in north Queensland.
Katter: 'I have been lied to'
Kennedy MP Bob Katter has been campaigning for the Hells Gates Dam for years, but said the announcement was a betrayal of trust by the government.
"I have been lied to, flagrantly lied to," he said.
Mr Katter claimed that height is needed to allow areas west of the Great Dividing Range to benefit from the Hells Gates irrigation scheme.
"In today's undertaking, the dam is nowhere near that high," he said.
"The dam is so low that it can't ever get through the Great Dividing Range, it hasn't got the height to do that."
"No Prime Minister has ever treated me like this."
Mr Katter did not answer questions about where he would direct his preferences in parliament in the event of a hung parliament after the next election.
Herbert MP Phillip Thompson said Townsville had the right infrastructure to support a growing agriculture industry.
"The Townsville Port is well placed to handle exports from the region," he said.
Election campaign in the wind
Shadow Minister for the Environment and Water Terri Butler said the announcement reeked of an election campaign and it was important for voters to remember there was still no business case for the proposal.
"They announced this before the 2019 election," Ms Butler said.
"We remain very open to this dam but of course we will want to see a business case and we want to make sure tax payers are getting value for money as you would expect a prudent economic manager to do.
"We are open to water infrastructure projects."
