Major construction on Torrens to Darlington Project a step closer

Major construction on South Australia’s North South Corridor – Torrens to Darlington (T2D) project is a step closer to commencing as early works continue to allow the decommissioning of existing utility services on South Road. 

More than 700 metres of APA Group gas services have already been installed along with over 600 metres of SA Water services, more than 1.2 kilometres of SA Power Networks services, and more than 2.3 kilometres of telecommunication services. 

“I’d like to thank motorists and locals for their patience during the work. 

“I know roadworks can be frustrating at times, but it’s vital we progress projects like these to ensure long-term benefits for commuters – such as smooth and safe journeys on our road network in and around Adelaide. 

“Good roads in Adelaide help us move forward, connecting where we want to go and making our community better. 

“Ensuring safety on Adelaide’s roads is a top priority for me. Maintaining our roads will help ensure that every individual deserves a secure journey while driving,” Federal Member for Adelaide Steve Georganas said. 

Ground investigation works have also been carried out in addition to the relocation of utility services at several sites to help gain understanding of the soil and ground water conditions along the South Road corridor. To date, about 693 boreholes have been drilled as part of ground investigations. 

Data collected from these investigation works will inform the detailed design of the tunnels and lowered motorway that will be built as part of the T2D Project. 

“An incredible amount of preparation is required to ensure the successful construction of a proejct of this magnitude. 

“People often ask why major works won’t commence in the T2D project until 2025, but an unprecedented amount of early works have already been completed. 

“Relocation of utility services might not be the most visible part of an infrastructure project, but these works are critically important in creating a safe passage for major construction works to be undertaken. 

“More than 18 kilometres have been drilled across many different sites as part of ground investigation works to gain a better understanding of the geotechnical and hydrogeological conditions that will be encountered when the tunnels are excavated. 

“We are all very keen to see the tunnels up and running, but this is the largest and most complex infrastructure project in the state’s history, and the team is working very hard to ensure we get the best possible outcome,” SA Infrastructure and Transport, Energy and Mining Minister Tom Koutsantonis said. 

Early works also involve resurfacing over three kilometres of South Road between Bennet Avenue, Melrose Park and Glengarry Avenue, Glendore. The works include removing the existing pavement and replacing it with new asphalt to ensure long-term safety as well as integrity of these sections ahead of the start of major construction. 

Resurfacing will continue along South Road, with works now underway on the section from Rothesay Avenue to Lloyd Street, Saint Marys. 

This project milestone comes as the Australian Government significantly increased its investment on T2D to match the South Australian Government’s $7.7 billion commitment. 

“The Australian Government is committed to building safer, more efficient road networks like this project in Adelaide. 

“Delivering these utility service relocations was a vital step forward and I’m very pleased to see the next phase of construction can continue on this important project. 

“This work will ensure smoother and more efficient journeys for commuters, locals, public transport users and businesses,” Federal Minister for Infrastructure, Transport, Regional Development and Local Government Catherine King said. 

Project alignment (source: T2D Torrens to Darlington)

Early works on the Torrens to Darlington Project are expected to be completed by 2025 and main construction works will follow suit. Tunnel boring machines for the Southern Tunnels are scheduled to begin digging in 2026 and the overall North South Corridor – Torrens to Darlington development is expected to be completed in 2031. 

“The resurfacing work on South Road is welcomed by my constituents in Elder, as well as by the many thousands of South Australians who use this important road corridor every day. 

“This work will provide a benefit now as well as leaving a legacy that will remain even after the North South Corridor is completed in 2031,” State Member for Elder Nadia Clancy said. 

“It’s fantastic to see the existing South Road being properly maintained while preparation for the final section of the North South Corridor projects ramps up. 

“We still need a good-quality road surface while the major construction work is ongoing, and it’s fantastic to see this work being done so quickly, and staged to minimise traffic disruption,” State Member for Badcoe Jayne Stinson said. 

The 10.5-kilometre T2D Project will deliver the final and most complex section of the North South Corridor, and it is the most significant infrastructure project ever undertaken in South Australia. 

The T2D Project is comprised of: 

• Southern Tunnels 
  • Run between the open motorway at Darlington to just south of Anzac Highway in Glendore and provide key connectivity to Anzac Highway 
  • Includes about four kilometres of twin three-lane tunnels 
• Open motorway linking the tunnels 
  • Connecting to key routes such as Richmond Road and James Congdon Drive, it will provide critical east-west connectivity and links to key destinations such as the airport 
  • Just over 2.5 kilometres in length 
• Northern Tunnels 
  • Run between James Congdon Drive and the existing open motorway south of Grange Road 
  • Includes about 2.2 kilometres of twin three-lane tunnels 

The North-South Corridor – Torrens to Darlington Project is estimated to support up to 5,500 jobs on average per year during its main construction phase. 

“The Australian and South Australian governments are partnering to deliver stronger, safer and more efficient roads and it’s important we all work together to support better outcomes for communities. 

“This is a project the people of Boothby regularly raise with me when I am out and about, as they know that this will help them commute to and from work every day,” Federal Member for Boothby Louise Miller-Frost said. 

Earlier this year, the Registration of Interest (ROI) process for a head contractor to deliver the Torrens to Darlington Project commenced. You can read more about it here. 

Source: Minister for Infrastructure, Transport, Regional Development and Local Government; T2D Torrens to Darlington (1, 2)