Main construction works are officially underway on the largest and most complex infrastructure project in South Australian history.
Heavy machinery is on-site and construction activity has ramped up at the Southern Precinct in Clovelly Park, marking the start of major works on the River Torrens to Darlington (T2D) Project that will create a non-stop South Road.
The project will allow motorists to bypass 21 sets of traffic lights between the River Torrens and Darlington, saving up to 40 minutes of travel time in peak hour traffic.
It’s estimated up to 550 workers will be employed at the Southern Precinct during peak construction, with the entire T2D Project to support approximately 5,500 jobs per year during main construction – with 90% of labour hours to be undertaken by South Australians.
“This is a project that’s been long talked about – everyone knows how important it is. Now we’re getting on with delivering it,” said Premier of South Australia, Peter Malinauskas (pictured).
“Residents in the Tonsley and Clovelly Park areas will be seeing works underway at the Southern Precinct between Tonsley Boulevard and Norrie Avenue.
“The purpose-built site is where the Tunnel Boring Machines will launch to construct the 4.5km Southern Tunnels, which will run from Clovelly Park to just south of the Glenelg Tramline in Glandore.
“This massive precinct, which is approximately 1300 metres long and 100 metres wide, will feature three large rigs and associated cranes to build the retaining walls, a 500-tonne gantry crane initially to lift and place the TBM components, multiple storage sheds including a large spoil handling facility and a large enclosed conveyor system to shift ground material from the tunnels to the spoil handling shed.”
The $15.4 billion T2D project is jointly funded by the Federal and SA Governments, with each contributing $7.7 billion.
The Southern Precinct – located between Tonsley Boulevard and Norrie Avenue on the western side of South Road – will become the purpose-built site from where the Tunnel Boring Machines (TBMs) will launch to construct the southern tunnels.
Two TBMs will launch from the Southern Precinct to construct the twin 4.5km Southern Tunnels, while the twin 2.2km Northern Tunnels will utilise a third TBM. TBM works for the Southern Tunnels are planned to begin in the second half of 2026.
The past few weeks have seen a significant increase in works on site, including the start of construction of the diaphragm walls for the TBM launch box – the first piece of permanent works on the project.
The diaphragm walls will be up to 35m deep and form the outside of the TBM launch box – a large open trench where the TBMs will be assembled and then begin excavating the tunnels.
A nearly 100m-long bentonite plant has also been constructed. This will produce and recycle bentonite slurry – a wet clay that is pumped into the trenches being excavated for the diaphragm walls to ensure ground stability. A water treatment plant, which will help the project treat and reuse water during the tunnelling process, has also been constructed.
“This is the last leg of a long journey to create the North-South Corridor – 78km of non-stop, traffic light-free motorway – and once complete, it will change the state for the better,” said Minister for Infrastructure, Transport, Regional Development and Local Government, Catherine King.
“When South Australian’s can bypass 21 sets of traffic lights on their journeys between River Torrens and Darlington, they won’t know themselves.”
