Government inks deal for three tunnel boring machines to work on Torrens to Darlington project, with plans to buy more

Extra tunnel boring machines will be delivered to South Australia to complete the Torrens to Darlington project – with hopes they will mean the work can be done faster.

Extra tunnel boring machines are set to be delivered to South Australia to complete the $15.4bn Torrens to Darlington project – with hopes that more equipment will mean the work can be done faster.

The state government and the River Torrens to Darlington Alliance have sealed a contract to buy three initial machines (TBMs) from world-leading manufacturer Herrenknecht.

Infrastructure and Transport Minister Tom Koutsantonis has also revealed plans to purchase another two smaller TBMs – with a third likely to follow – to conduct excavation work between the project’s main tunnels.

Mr Koutsantonis inked the deal to purchase the initial three machines at a signing ceremony at Herrenknecht headquarters in Germany on Friday.

Infrastructure and Transport Minister Tom Koutsantonis and Martin Herrenknecht, founder of the company contracted to provide the tunnel boring machines, sign the contract in Germany. Picture: Supplied

The total cost of all TBMs is expected to be about $180m.

Machine components will be manufactured in Germany and China, then assembled and tested in China, before they are delivered to Adelaide.

The first is expected to arrive late next year, and will need to be assembled and commissioned before tunnelling work can begin.

Tom Koutsantonis and Department for Infrastructure and Transport chief executive Jon Whelen at Herrenknecht headquarters in Germany.

The initial three TBMs will measure about 100m in length and 15m in diameter – roughly the height of the Thebarton Theatre or Edwardstown Bunnings.

Having three machines will mean that work on the northern and southern tunnels can happen at the same time, which will help keep the project on track for its 2031 completion deadline – or even earlier.

The other, smaller TBMs will be 4.1m-diameter and will be used to construct the cross-passages of the tunnels, which will save time and work on conventional construction methods.

A render of the inside of the completed southern tunnel of the Torrens to Darlington project. Picture: Supplied

A render of the inside of the completed northern tunnel of the Torrens to Darlington project. Picture: Supplied

Mr Koutsantonis said Friday’s deal represented “one of the biggest purchases of building equipment in South Australia’s history”.

“The fact we’ve also confirmed additional purchases of up to three smaller TBMs to fast-track related works gives us even more confidence that we will deliver this project on budget and on time – if not even earlier,” he said.

“Tunnelling projects all across the globe have entrusted this nearly 50-year-old company with the delivery of their tunnel boring machines, and it’s no surprise given Herrenknecht’s cutting-edge, industry-leading technology.

“We are getting closer to the start of major works and it won’t be long until the dream of saving 30 to 40 minutes of travel time between West Hindmarsh and Darlington becomes a reality.”

Herrenknecht has delivered TBMs for major projects around the world, including the Sydney Metro and the North East Link and West Gate Tunnel Projects in Melbourne.

The purchase of the first three TBMs came two weeks after the main construction contract for the project was officially signed by a consortium of John Holland, Bouygues Construction, Arcadis Australia, Jacobs and Ventia.

The Torrens to Darlington project – the final 10.5km section of the North-South Corridor – will feature southern and northern tunnels, which will be connected by an open motorway.