Treasurer Jim Chalmers’ third federal budget reversed some of the cuts to South Australian road projects made last November, with the government to now spend $120 million on previously-announced upgrades to the Verdun and Mount Barker interchanges.

The upgrades were originally part of a $200 million federal investment in a broader upgrade and Hahndorf bypass, which is no longer going ahead.

The federal government will also spend an extra $100 million for ongoing upgrade work to the South Eastern Freeway, a project already costing the Commonwealth $120 million.

State Treasurer Stephen Mullighan said the additional freeway money would be spent on “a range of safety upgrades, particularly along the length of the descent from Crafers down to the tollgate”. It comes after another out of control truck crashed at the bottom of the freeway this morning.

Asked whether the $100 million for the South Eastern Freeway was new money or a blowout on the existing upgrades, Mullighan said: “It’s sort of both.”

“There’s been some more works that have been identified for what’s been called the Managed Motorway Project on the South Eastern Freeway,” he told ABC Radio Adelaide.

“And so part of that $100 million will go to delivering a broader suite of works but also part of that money will recognise that the cost of delivering these projects continues to escalate.”

Mullighan said the Department for Infrastructure and Transport was doing “detailed planning work… to work out how a truck bypass can be delivered around the Adelaide Hills”.

“The difficulty with the South Eastern Freeway is that while hundreds of trucks use it every day and manage not to come a cropper down at the bottom, the vast majority of those trucks have business in the CBD,” he said.

“But there is a portion of trucks, particularly the bigger trucks and the articulated trucks, that don’t [and] could bypass.

“So a bypass will deliver some reduction in truck traffic’s some commensurate safety upgrades.”

Treasurer Stephen Mullighan and Adelaide Hills MP Dan Cregan speaking to media today. Photo: Thomas Kelsall/InDaily

Around 7/10 trucks that come down the freeway have business in greater metropolitan Adelaide, Mullighan said, adding: “That means that we can and should be directing those remaining trucks to make use of the routes that are already available.”

Funding for the $202 million Truro Bypass in the northeast was not reinstated last night. The project was designed to reroute trucks along the Sturt Highway away from Truro’s main street but was cut last November in the federal government’s infrastructure review.

Meanwhile, there was no announcement last night about additional funding for the stalled Tarrkarri Aboriginal cultural centre on North Terrace.

The state government is searching for additional funding for the project – which could cost between $400 to $600 million – from both the federal government and a private philanthropist.

There is currently only $85 million in federal government funding on the table for the project under an “Adelaide City Deal” signed between the former Marshall and Morrison governments in 2019.

The state government was set to fund the remaining $115 million when the project was costed at $200 million before being advised in October 2022 of a $50 million cost blow-out and that the building would only be of “local state-level standard”.

Mullighan said there are “still ongoing discussions with the Commonwealth Government about whether they’ve got a broader appetite to invest further in that Tarrkarri project”.

“There was no further announcement in the federal budget last night and I think that reflects that those conversations have not concluded between the state and the Commonwealth government.

“And they also haven’t concluded with other third party or private sector potential contributors as well.”

Mullighan told reporters a short time ago that the state government was not expecting a federal funding announcement about Tarrkarri at the federal budget.

Asked if there was a gap between what the state government wants for Tarrkarri and what the federal government is willing to fund, Mullighan said: “I’m not going to provide a running commentary on those discussions.”

“They’re being held in good faith, and I think the approach from the federal government and the Prime Minister has been very open minded about it.

“We’re giving them every opportunity to try and provide funding towards it.”

Undisclosed funding to build Adelaide’s new subs yard

The Albanese Government is not revealing how much it will spend to build a nuclear-powered submarine construction yard at Osborne.

The budget papers show the federal government will provide Australian Naval Infrastructure, the government business enterprise which owns the shipyards infrastructure, with an “equity injection” over four years from 2024-25 “to progress priority construction and design works in support of the nuclear-powered submarine construction yard in South Australia”.

“The financial implications of this measure are commercially sensitive and not for publication (nfp) as disclosure would impair ANI’s position in negotiating contracts for these services,” the budget papers state.

Premier Peter Malinauskas left for the United States on Tuesday to visit the two shipyards building nuclear-powered submarines in the US and meet with figures from the US defence program and submarine supply chain.

The federal budget contains $101.8 million over seven years to support workforce development to build the nuclear-powered submarines.

This includes $68.4 million over seven years to support the new Skills and Training Academy at Osborne and $34.7 million over six years to deliver a pilot apprenticeship program in trades required to support nuclear-powered submarines.