The T2D Project is the final 10.5km section of the North-South Corridor, and will complete 78km of non-stop, traffic light-free motorway between Gawler and Old Noarlunga.
It comprises twin three-lane tunnels, lowered and ground-level motorways, as well as overpasses and underpasses and upgrades at key intersections. More than half of the project will be tunnels.
The consortium plans to procure three TBMs, instead of the two previously anticipated – which will mean both north and south tunnels can be constructed concurrently.
The additional TBM will speed up construction so the project so the project could be completed earlier than the stated 2031 deadline.
The consortium has also proposed plans for “innovative tunnel portal arrangements” that enable improved and lowered motorway sections with faster construction times and reduced costs; improved tunnel design and shorter cut and cover tunnel sections to reduce energy use and costs, and minimise impacts to local communities; and innovation for the construction of tunnel cross passages, and other systems elements of the tunnels.
Main construction works on what is the biggest infrastructure project in South Australia’s history, are proposed to start in 2025, with TBM works for the southern tunnels planned to begin in the second half of 2026.
