Major Contract

Torrens to Darlington - Stage Two - River Torrens to Anzac Highway

Torrens to Darlington - Stage Two - River Torrens to Anzac Highway

The 10.5-kilometre Torrens to Darlington (T2D) project is the final section of North-South Corridor. The section will allow motorists to bypass 21 sets of traffic lights when travelling between the River Torrens and Darlington. 

Also referred to as Airport Link and Northern Tunnel, Stage Two includes approximately 4.5 kilometres of motorway connecting River Torrens and ANZAC Highway. 2.3 kilometres of Stage Two is to be constructed in twin three-lane tunnels.

Planning, early works, procurement and approvals processes for Stage One and Two will run concurrently. 

Key Dates

Apr 2019 Project Announcement
2026 Expected Construction Commencement
2030 Expected Construction Completion

Funding contributions

Federal Government
SA Government


Procuring Agency: Department of Infrastructure and Transport
Related contracts:
Master Advisory Services contract
Successful Tenderer - A Joint Venture of Aurecon and Mott MacDonald

Reference design
Successful Tenderer - A Joint Venture of GHD, WGA and WSP

Tunneling investigation
Successful Tenderer - PwC, SMEC, WSP and Tunnelling Solutions


Apr 2019 The Federal and South Australian Governments jointly committed $5.4 billion for the Torrens to Darlington section of the North-South Corridor.
Dec 2019 After reviewing the initial business case, and on advice from Infrastructure SA, the SA Government announced it will establish a Program Management Office within the Department of Planning, Transport and Infrastructure in early 2020.
Nov 2020 The 2020-21 SA Budget allocated $30.5 million over FY2020-21 to finalise the business case for Torrens to Darlington section.
Nov 2020 The South Australian Government commenced market sounding process for the Torrens to Darlington section. Registration of Interest were called from 17 November to 25 November, with interviews with selected participants, as well as written feedback submission concluding on 18 December 2020.
Nov 2020 The South Australian Government announced the commencement of reference design phase.
Nov 2020 Following the selection of preferred option, new geotechnical testing commenced.
Nov 2020 A 'hybrid+' option was selected as the preferred design option for Torrens to Darlington. The specific details of the hybrid+ option design, operation and connectivity are to be presented as investigation works and the reference design process are progressed.
Jan 2021 The Government of South Australia called for Registrations of Interest to participate in the market sounding process for transaction advisory services for both stages of the Torrens to Darlington section of the North-South Corridor.
Feb 2021 A Joint Venture of Aurecon and Mott MacDonald was awarded the Master Advisory Services contract for the Project.
Feb 2021 The Government of South Australia issued the Request for Tenders for Phase Two Geotechnical Investigation Studies for the North-South Corridor – Torrens to Darlington, with tenders closing on 16 March 2021.
Mar 2021 A Request for Tender (RFT) for the provision of Transaction Advisory Services was released. The RFT closed on 13 April 2021.
Jun 2021 The 2021-22 South Australia Budget revealed a change in scope and increase in cost for the Torrens to Darlington project. The scope now includes an additional lane and wider tunnels, meaning the scope is now for twin three-lane tunnels across Stage One and Stage Two of the project. The change in scope has raised the estimated total cost from $8.9 billion to $9.9 billion.
Aug 2021 The South Australian Department for Infrastructure and Transport opened a Registration of Interest for the Phase Two Market Sounding Process for the North-South Corridor – Torrens to Darlington project, closing on 1 October. This market sounding process was expected to inform packaging, procurement, and delivery approaches across the three key project delivery sectors of contractors, operators and maintainers, and the wider supply chain.
Sep 2021 A Request for Tender (RFT) opened for phase three and four ground investigation studies.
Nov 2021 The North-South Corridor Project Delivery Office opened a Request for Tender for Technical and Engineering Advisory Services during the pre-procurement, procurement, and detailed design phases, with the RFT closing on 21 December 2021.
Nov 2021 The SA Government released the Reference Design for the ANZAC Highway to Darlington and River Torrens to ANZAC Highway sections. The Designs confirm the two sections will include a combined 10.5 kilometres of motorway, comprising seven kilometres of tunnels.
Feb 2022 The Federal Government announced $2.26 billion for Stage Two of the T2D. T2D is now fully funded across both stages.
Mar 2022 The 2022-23 Federal Budget allocated $2.3 billion to Stage Two of the T2D over four years, confirming February's announcement.
Estimated Total Cost
Procurement approach
Unconfirmed |
South Australia |
Infrastructure Australia status
Priority Initiative (near-term, 0-5 years)