South Road transformed ahead of $15b Torrens to Darlington project
Thomas Kelsall
South Road was once the gateway to Adelaide's car industry, filtering hundreds of manufacturing workers into a sprawling factory in the southern suburbs.
But the remnants of that major employment site, which started as a Chrysler factory and was later taken over by Mitsubishi until the latter closed its doors in 2008, are now hard to find.
The factory was repurposed into a business precinct in the 2010s, and the last traces of the site have been demolished to make way for SA's largest-ever infrastructure project — the Torrens to Darlington (T2D).
Nearby in Clovelly Park and St Marys, vacant land now runs along the western side of South Road where car dealerships, auto repair stores and electrical wholesalers used to trade.
The Tonsley Hotel, a pub built in the 1960s amid the car manufacturing boom, is also gone — one of more than 300 properties razed to make way for the T2D.
The $15.4 billion road project, due to be completed in 2031, is already reshaping the landscape of the western and southern suburbs.
But will it be worth the hefty price tag?
The final piece of the puzzle
The South Road tunnels are the final stage of a vision dating back to the 2000s to connect Adelaide's south (Old Noarlunga) with Adelaide's north (Gawler) via a non-stop, 78-kilometre motorway.
While the T2D section is only 10.5 kilometres, it is by far the most complex part.
It will require digging roughly 4km of parallel three-lane tunnels from Darlington up to Glandore and then another 2.2km of tunnels between James Congdon Drive and the Brickworks Marketplace in Torrensville.
Between the two tunnel sections is a 2.5km stretch of South Road that will undergo a complete overhaul with new east-west overpasses, cycling paths and urban green space.
The SA government's core argument for the T2D is that it will make car and freight travel quicker and avert "catastrophic congestion" forecast across Adelaide's road network by 2031.
According to government transport data, more than 50,000 vehicles use South Road each day, the average speed along the T2D section is below 30 kilometres per hour, and the crash rate is up to 11 times higher than the Northern Expressway's.
James Hancock, deputy director of the University of Adelaide's SA Centre for Economic Studies, said Adelaide was currently "one of the worst" among Australia's capitals for having "major transport routes deeply embedded in urban areas".
"The other big effect is that people who live west of South Road, many of them are crossing South Road on a daily basis commuting east-west to the city," he said.
"And in rush hour, South Road is really the most significant bottleneck to that traffic flow."
Once the 80kph tunnels are completed, the government says commuting from Darlington to West Hindmarsh will only take nine minutes — a saving of 30 to 40 minutes in peak hour.
But Donna Ferretti, a former director of strategic and regional planning at the transport department, said "we'll have to wait and see" whether the tunnels would improve travel efficiencies across metropolitan Adelaide.
"That's my concern as an urban planner, that … the inevitable outcome of this project is it's actually going to increase the amount of traffic across the metropolitan network and increase the congestion, which will lead to further demands for increased road infrastructure," she said.
"And so the cycle goes on and on and on.
"We tout Adelaide as being one of the most liveable cities in the world [but] that banner will be under serious threat with more and more road projects."
A South Road transformation
To make T2D work, the Transport Department earmarked 524 properties for compulsory acquisition, including 289 homes and 200 commercial or industrial properties.
Some of that space, such as the land where the Tonsley Hotel once stood in Clovelly Park, is set to become new green space.
University of South Australia senior lecturer Andrew Allan said although compulsory acquisitions caused "permanent upheaval" in people's lives, they could also improve South Road's landscape once the project was finished.
"And then because of the greater connectivity, the land becomes more valuable," Mr Allan said.
"You might see increased [housing] densities occurring, but remember, it's car-dependent, so there's a limit to how far you can go with that."
City of Marion Mayor, Kris Hanna, said there had been a "significant impact" on the roughly 170 business and property owners acquired in his council area, and he estimated an annual rates loss of $400,000.
But he said the council supported the road project and anticipated it would "positively impact" remaining businesses by removing traffic that was "just passing through".
Others are more sceptical of the project's amenity benefits.
Jennifer Bonham, spokesperson for public transport lobby group the Transport Action Network, said "the amount of land" on either side of South Road that "you simply can't use" would be an issue.
She said she was also concerned the above-ground portion of South Road would remain congested.
"I'm not sure that we're going to have much of a reprieve [from traffic] — even in those sections where there's the tunnel underneath and South Road looks perhaps a little bit neater than what it does now," Ms Bonham said.
Averting a road network 'collapse'
South Australia's $7.7 billion contribution to the T2D puts significant demand on the state's coffers.
In December, Treasurer Stephen Mullighan said the T2D — along with the $3.2 billion Women's and Children's Hospital, which is under construction — would leave the state government unable to afford any comparably-sized projects this decade.
But Transport and Infrastructure Minister Tom Koutsantonis is adamant the tunnels are worth every cent, arguing that without them, "we're on the precipice" of "the grid network collapsing in Adelaide".
"The cost is worth it because it means the very functioning of the city," he said.
Mr Koutsantonis also said a project without tunnels would "not have been that much cheaper" and would have incurred greater social costs.
"If we just demolished homes and carpeted the North-South Corridor, you'd have a lot of economic destruction," he said.
"We've seen some of it, but we saved a lot of businesses, saved a lot of homes, saved a lot of communities, by doing the tunnels."
