RAA welcomes the release of the Torrens to Darlington (T2D) reference design

14 December, 2022

RAA welcomes the release of Torrens to Darlington (T2D) reference design – the final piece of the North-South Corridor.

Following a comprehensive review, the new State Government have today confirmed it will deliver a twin-tunnel solution, completing the continuous 78- kilometre non-stop motorway.

RAA’s Senior Manager of Safety and Infrastructure Charles Mountain said the 10.5-kilometre T2D project is the final piece in the 78-kilometre North-South Corridor puzzle.

“RAA has long been advocating for this crucially important project for the state, as the full benefit of the North-South Corridor won’t be realised until the T2D project is complete.”

“Once complete, the NSC will be a non-stop motorway from Old Noarlunga to Gawler, forming the backbone of North-South vehicle movement through metropolitan Adelaide.”  

According to the State Government, the new reference design will allow motorists to bypass 21 sets of traffic lights, which could save them up to 20 minutes in peak periods.

“The completion of the North-South Corridor will deliver significant benefits for South Australian motorists, including reducing travel times and improving road safety,” said Mr Mountain.

“No one likes being stuck in traffic and reducing time motorists spend in their cars waiting at traffic lights will also reduce fuel consumption and wear and tear on their vehicles – saving them money in the long run.  

“It will also benefit freight and business by delivering better access to Adelaide Airport, Outer Harbor shipping terminal and to our regions – boosting productivity and efficiency.

“We will be seeking a more comprehensive briefing from the Department of Infrastructure and Transport to get greater clarity around the project details so we can continue to communicate those to our members.”

The project includes the following key areas:

  • A 6km Southern Tunnel section which extends from the recently completed Darlington Upgrade Project to just south of Anzac Highway. This section provides key connectivity to Anzac Highway and includes about 4kms of twin three-lane tunnels with the balance in open motorway at each end of the tunnels.
  • At just over 1km in length, the Tunnel Connector links the Southern and Northern tunnels via an open motorway. Connecting to key routes such as Richmond Road and James Congdon Drive, this section will provide critical east-west connectivity and links to key destinations, such as the airport.
  • A Northern Tunnel section which includes about 4kms of motorway between James Congdon Drive and the existing motorway south of Grange Road, with just over 2kms of twin three-lane tunnels and the balance in open motorway at each end of the tunnels.

To find out more about the project, visit the state government’s website: Home – River Torrens to Darlington – Department for Infrastructure and Transport (