Preferred builder has been announced for Torrens to Darlington Project

A preferred delivery partner for the final stage of South Australia’s long-awaited North South Corridor has been announced and the project remains on track to be completed by its 2031 deadline. 

Following an exhaustive procurement process that commenced in January 2023, the consortium comprising of John Holland, Bouygues Construction, Arcadis Australia, Jacobs and Ventia has been chosen as the preferred alliance partner to deliver the River Torrens to Darlington Project (T2D Project). 

“My Government wants to use nation-building infrastructure to boost jobs, boost productivity and get people home safer. 

“The completion of the North South Corridor will do all three. 

“My Government and the Malinauskas Government are getting it done,” Prime Minister Anthony Albanese said. 

The consortium has confirmed that it can deliver the T2D Project on budget, delivering significant travel, economic and community benefits for South Australians. 

Each company under the consortium has a track record of successfully delivering major tunnelling and infrastructure projects across Australia and internationally – including the WestConnex, Sydney Metro and South West Tunnel and Station Excavation and Sydney Airport Rail Link. 

The announcement of the preferred alliance partner provides further certainty that project delivery is on schedule. 

“The Australian Government is pleased to be partnering with the South Australian Government to deliver the infrastructure that South Australia needs, including the major investment in the T2D. 

“The project will not only revolutionise the way locals move around their region, but unlock new transport opportunities for tourists to visit the area as well. 

“Our Government is working closely with the South Australian Government to deliver meaningful projects and actions, ensuring our planning and investment comes together to provide the best and safest outcomes for commuters and communities,” Minister for Infrastructure, Transport, Regional Development and Local Government Catherine King said. 

Although the project is expected to be completed on schedule, South Australians will likely be able to enjoy the full benefits of the project sooner than expected as the project will utilise three tunnel boring machines (TBMs) at the same time instead of the proposed two. 

The consortium’s tender detailed a plan to procure three TBMs to allow for both the north and south tunnels to be constructed simultaneously. The additional TBM gives reasonable expectation that the nation-shaping project can be completed by the set deadline or even earlier. 

Enhancements from the 2022 Reference Design proposed by the consortium include: 

• A connection free from traffic lights between the motorway and James Congdon Drive, providing seamless access to and from the CBD 

• Innovative tunnel portal arrangements that enable improved and lowered motorway section with faster construction times and reduced costs 

• More trees planted to help green the corridor 

• Improved tunnel design and shorter cut and cover tunnel sections, which will reduce energy use and costs, and minimise surface impacts to communities next to the T2D motorway 

• Innovation for the construction of tunnel cross passages, and other systems elements of the tunnels 

• Improved experience for active travel users with universally accessible paths, shared0use paths and active travel corridors, with regular safe east-west connections 

“For decades, South Australians have waited for a non-stop trip from North to South through Adelaide. 

“Finally, we are getting it done. 

“This is a significant milestone – one that will see thousands of South Australians employed building the biggest infrastructure project in the state’s history. 

“We have three Tunnel Boring Machines operating instead of two – guaranteeing this project will be delivered on time. 

“In fact, once the TBMs arrive next summer, we’re hopeful the delivery deadline can be brough forward. 

“Once completed, this project will see traffic move between West Hindmarsh and Darlington in just nine minutes, saving 30 to 40 minutes of travel time during peak hour,” Premier Peter Malinauskas said. 

Project alignment (source: T2D Torrens to Darlington)

The consortium will begin setting up a construction site at the southern laydown area in Clovelly Park in the coming weeks and will engage with local communities as early works are carried out along the corridor. 

Main construction on the T2D Project is expected to commence in 2025, with works on the TBM for the southern tunnels to begin in the second half of 2026. 

The T2D Project will support about 5,500 jobs annually during main construction, with up to 90 per cent of labour hours to be undertaken by South Australians. 

This massive transport infrastructure project will also deliver opportunities for South Australian businesses, with over 300 local businesses already registering their interest in being involved as a subcontractor on the T2D Project through the Industry Capability Network. 

In addition, the consortium is committed to a minimum of 6 per cent Indigenous employment alongside opportunities for more than 600 apprentices and trainees as well over 220 long-term unemployed people. 

“This is a historic day for South Australia, as we now know who will be delivering the largest infrastructure project in our state’s history – and we hope to deliver it earlier than previously anticipated. 

“We are delivering certainty for South Australians by making good on our promise to award the Alliance contract for the River Torrens to Darlington Project by the third quarter of 2024. 

“The successful consortium comes with an incredible wealth of knowledge and experience, and has committed to deliver the project on budget, providing South Australians with far-reaching benefits,” SA Minister for Infrastructure and Transport Tom Koutsantonis said. 

The River Torrens to Darlington Project will deliver the final 10.5-kilometre section of the North South Corridor, completing the 78-kilometre non-stop, traffic light-free motorway between Gawler and Old Noarlunga. 

Once completed, motorists will be able to bypass 21 sets of traffic lights while travelling through two separate tunnels and an open motorway – which will have three lanes in each direction. 

The Southern Tunnel will span 4 kilometres between the open motorway at Darlington to just south of Anzac highway in Glandore and will provide a key link to Anzac Highway. The Northern Tunnels, on the other hand, will be 2.2 kilometres long and will run between James Congdon Drive and the existing open motorway south of Grange Road. 

Meanwhile, the 2.5-kilometre open motorway that connects the two tunnels will also provide connections to key routes such as the Richmond Road and James Congdon Drive, delivering critical east-west connectivity and links to key destinations including the airport. 

“This work will get residents of Boothby home quicker and safer, and take thousands of vehicles off local roads. 

“This is yet another demonstration that the Australian and South Australian governments are investing in the infrastructure Adelaide needs to keep up with growing demand. 

“Once completed, the T2D Project won’t just benefit locals in my electorate and beyond, but also the millions of tourists who visit the area each year,” Federal Member for Boothby Louise Miller-Frost MP said. 

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