The state’s transport department chief says $9.9 billion originally allocated for the final stage of the South Road upgrade wasn’t enough, but can’t put a final price on the huge project.

An artist impression of the North-South Corridor

Appearing before parliament’s Budget and Finance Committee this morning, Department of Infrastructure and Transport CEO, Jon Whelan, said work was still underway to announce a new reference design for the Torrens to Darlington project before the end of the year.

The major South Road upgrade, allocated $9.9 billion in joint-funding by the state and federal government, has been under a cloud since the Malinauskas Government came to office in March, with the end date pushed out to 2031 and major works not due to start until 2027.

Whelan, who replaced former Transport Department CEO Tony Braxton-Smith in April, said the previous timeline for North-South Corridor was unrealistic, but maintained it would be finished in 2031.

Opposition MLC Stephen Wade asked Whelan if he could “advise what the current final cost estimate of the Torrens to Darlington section of the North-South Corridor is”, to which Whelan replied: “No.”

Wade then asked Whelan whether he expected the project’s “original cost estimate” of $9.9 billion would increase.

Whelan replied: “There was $9.9 billion of funding… it would not be right to say that the reference design could have been constructed for that level of funding.”

Asked whether he agreed with Koutsantonis’ statement earlier this year that he “wouldn’t be surprised” to see the project’s costs exceed $9.9 billion, Whelan said: “I’d agree with the minister’s statement.”

“Previously this project was presumed to have been going to market in April of this year,” Whelan told the committee.

“We are not in a position to go to market yet, and we never were in a position to go to market in April of this year.

“So as far as any delays, I think it would be remiss to say there are delays to the project – what it has been is we’ve had to relook at the old reference design and investigate some options which were of some concern.”

 Whelan also did not disclose to the committee the potential number of compulsory acquisitions that could stem from a new reference design, although said it has been made “quite public by the minister… that it’s likely that the number of acquisitions could increase”.

“On the old reference design there was 393 full acquisitions and 13 partial acquisitions,” Whelan said.

“I couldn’t comment to you on the numbers that may have to be acquired should there be changes to that reference design.”

The Torrens to Darlington project came under heightened scrutiny this year after it was revealed the state’s infrastructure advisory body, Infrastructure SA, had warned the former Marshall Government that the $9.9 billion project had “major issues and/or risks”.

An Infrastructure Australia analysis of the business case published in February found that the upgrade proposal had a benefit-cost ratio of 0.7. Any number below one means that the costs outweigh the benefits.

Whelan said one part of the previous reference design that had raised concern was the single-lane elevated ramp from South Road to Anzac Highway.

“I would have advised the minister that that solution – having an elevated single lane going into Anzac Highway – would not give the optimal solution for this project,” Whelan said.

“A single lane on an elevated structure has the likelihood if there was an incident on that structure to actually have traffic bank back into the tunnel.”

The previously proposed single-lane elevated ramp off South Road and onto Anzac Highway

Asked by Wade if it was appropriate to describe the single lane ramp as “unworkable”, Whelan said: “I think for a currently funded $9.9 billion project – one of the largest infrastructure spends this state has and may likely ever see – to have a solution that would have one lane coming… onto Anzac Highway would put that component of the project at serious risk and would therefore be unworkable.”

Asked by Wade if anyone in the department advised the Marshall Government of this, Whelan said: “I can’t comment on that, I wasn’t the chief executive at that time.”