South Rd upgrade between River Torrens and Darlington could top $5 billion, as much as all other upgrades combined

Fixing the final piece of South Rd, between the River Torrens and Darlington, is expected to cost as much as the rest of the puzzle combined — but a toll will not be imposed to help fund the estimated $5 billion project.

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Fixing the final piece of South Rd, between the River Torrens and Darlington, is expected to cost as much as the rest of the puzzle combined as taxpayers face a $5 billion-plus bill.

The Sunday Mail yesterday revealed three options are being considered by the State Government to complete a non-stop freeway between Gawler and Old Noarlunga.

The last remaining portion is to link the recently completed Torrens to Torrens with the Darlington Upgrade that is currently underway, a troublesome 10.5km stretch which runs through built-up suburbs and commercial districts just north and south of Anzac Highway.

The three solutions being examined by the State Government are one super tunnel, or a hybrid option of two that includes traffic returning to the surface between Anzac Highway and Edward St in Melrose Park.

A tunnel-free design is also being examined, which would be similar to the Torrens to Torrens build.

A concept image of the River Torrens to Darlington Project.

Transport Minister Stephan Knoll said a decision would be made this year on the solution that was best for local communities, as well as traffic.

He also warned of the significant cost for a project that could take a decade to finish — but ruled out the option of a toll.

Speaking to FiveAA on Monday morning, Mr Knoll said tolls were not an option to pay for what could be SA’s biggest ever public infrastructure project.

“We took to the election a pretty clear policy of not putting tolls on roads and we’re sticking to that commitment,” he said.

“To be honest, we don’t need it to be able to do what we need to do. That final price tag is something that’s being worked through, and again it depends on which option we choose ... (but) the dollar figure is going to be huge.”

Speaking to The Advertiser on Sunday, Mr Knoll said it was “a once-in-a-lifetime opportunity and we have to get this right”.

“There are pros and cons of the three options that have been put on the table, but it would be fair to say that the hybrid tunnel option could be one that delivers the best solution,” he said.

“It is fair to say that this remaining 10.5km stretch of the corridor is going to match or exceed, potentially, all the other money that has been invested to date on this very important road.”

The Advertiser has tallied the cost of other finished or committed projects on South Rd, including Torrens to Torrens and the Regency to Pym St build set to start later this year.

River Torrens to Darlington Project — North-South Corridor project.

Combined, they tally a massive $4.95 billion. To date, the most expensive public projects in SA have been the $2.4 billion new Royal Adelaide Hospital and $2.2 billion desal plant.

It is common for the Federal Government to pay about half the cost of big road projects.

Opposition Leader Peter Malinauskas urged action on the project, saying Premier Steven Marshall had failed to invest in infrastructure or secure Canberra funding.

A concept image of the River Torrens to Darlington Project.

“Let’s complete this project rather than just have a talkfest,” he said.

Industry groups also urged a swift decision so that construction firms could keep skills and expertise in SA and businesses along the corridor had certainty about their futures.

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