First tunnel boring machine on its way to build T2D Project tunnels

The first of three tunnel boring machines (TBMs) to be used to build the tunnels on the Torrens to Darlington (T2D) Project is now on its way to South Australia following its successful factory acceptance testing in China. 

Components of the TBM are manufactured in Germany and China, and they have been rigorously tested to ensure all critical functions such as the cutterhead, drive motors and thrust cylinders meet technical and operational specifications. 

Once all components arrive in Adelaide, the TBM will be assembled and commissioned at the project’s Southern Precinct in Clovelly Park. It is one of two TBMs to be launched from this site to construct the 4.5-kilometre Southern Tunnels that runs from the open motorway at Darlington to just south of Anzac Highway in Glandore. 

Excavation works on the Southern Tunnels are planned to begin in the second half of 2026. 

A third TBM will be launched from the Central North Precinct at Richmond and it will build the twin 2.2-kilometre Northern Tunnels that run between James Congdon Drive and the existing open motorway south of Grange Road. 

“We can’t wait to welcome our first Tunnel Boring Machine to South Australia, following the successful factory acceptance testing in China. 

“Stretching approximately 100m in length and 15m in diameter, these enormous machines are the biggest pieces of construction equipment ever used in SA. 

“This is a pivotal step in the largest infrastructure project in our state’s history and in delivering a non-stop South Road,” Minister for Infrastructure and Transport Emily Bourke said. 

Meanwhile, works will commence this month to install the rebuilt South Road Tram Overpass, a 95-metre steel arch bridge that requires 1,200 tonnes of structural steel as well as 520 cubic metres of concrete poured into the piles. 

The overpass is part of the $870 million Tram Grade Separation Projects. 

“It’s fantastic to see such major infrastructure projects reaching these milestones. 

“I very much welcome the arrival of the Tunnel Boring Machines that will deliver one of the biggest infrastructure projects in the state’s history. 

“With the Tram Grade Separation removal, particularly with the boom gates going, we can already see the difference it makes to traffic congestion,” Federal Member for Boothby Louise Miller-Frost said. 

“It’s great that work is progressing so quickly, and the removal of the level crossing is already improving traffic flow and safety. 

“I want to thank tram users for their patience during the partial line closure and encourage everyone to make the most of the substitute buses,” Labor candidate for Morphett Toby Priest said. 

The T2D Project will deliver the final 10.5-kilometre section of the North-South Corridor in South Australia, completing 78 kilometres of non-stop, traffic light-free motorway between Gawler and Old Noarlunga. 

The project is comprised of: 

• Southern Tunnels 

• • Run between the open motorway at Darlington to just south of Anzac Highway in Glandore and provide key connectivity to Anzac Highway 

• • Includes about 4 kilometres of twin three-lane tunnels 

• Open motorway linking the tunnels 

• • Connecting key routes such as Richmond Road and James Congdon Drive, it will provide critical east-west connectivity and links to key destinations such as the airport 

• • Just over 2.2 kilometres in length 

• Northern Tunnels 

• • Run between James Congdon Drive and the existing motorway south of Grange Road 

• • Includes about 2.2 kilometres of twin three-lane tunnels 

“This will be the biggest year ever for building and construction in South Australia. 

“We’re on track to deliver more than $21 billion dollars’ worth of work building our homes, roads, schools, hospitals and more. 

“Our industry is a major reason why South Australia’s economy has been one of the best in the nation. 

“More than 93,000 South Australians work in building and construction and there’s more than 26,000 construction businesses, both record highs. Our insolvency rate continues to be the lowest in the nation. 

“The benefits of a strong building and construction industry flow right through the economy,” Master Builders Association SA CEO Will Frogley said. 

Source: Government of South Australia – Media Releases; T2D Torrens to Darlington (1, 2)