Plan to ‘abandon’ nearly built motorway in Sydney’s south secretly explored

Abandoning construction of a multibillion-dollar motorway in Sydney’s south has been seriously considered by the NSW government amid a long-running dispute with contractors over who bears the major cost of fixing tunnels damaged by sinkholes more than two years ago.

The revelation in confidential documents sheds light on the extent of options the government has been secretly weighing up for the four-kilometre underground M6 motorway between Arncliffe and Kogarah since tunnelling was halted indefinitely on the troubled project in March 2024.

Emails show senior Transport officials discussed a confidential “scoping study for abandoning [the] M6” late last year as the dispute with a consortium responsible for building the stalled $3.2 billion project escalated.

The scoping study and related reports, which have not been released to the public, were referenced in an email between senior bureaucrats labelled “strictly confidential and legallly [sic] privileged”.

The government has already shelled out at least $2.7 billion on the motorway, and only about 240 metres of twin tunnels are left to build.

An email from a transport official in April this year regarding the “risk on abandonment” has also been deemed privileged. The emails are contained in internal Transport for NSW documents released following a move by deputy Liberal leader Natalie Ward in the upper house.

Text messages also show NSW Motorways chief executive Camilla Drover arranging conversations and meetings early this year about the M6 with the top brass at CIMIC. The engineering giant owns CPB, the lead contractor in the consortium responsible for building the motorway.

Coalition roads spokesman Mark Coure said the internal documents raised serious questions about the government’s commitment to delivering the M6, and the roads minister needed to come clean on whether it would proceed with the plan to abandon the project.

“If Labor has been discussing abandoning the M6 behind closed doors, the community deserves to know. Stop the secrecy, stop the spin and tell people the truth,” he said.

“Taxpayers are investing billions of dollars into this project. They have every right to know what is happening and what the government’s intentions are.”

Roads Minister Jenny Aitchison said her priority was ensuring the government got the best deal for the people of NSW.

“We want to see this project completed, but we will not hand over a blank cheque. The government examined options to get this project moving and has acted to address the ongoing delays with the project,” she said in a statement.

Transport for NSW echoed her remarks, saying the government was committed to completing the M6 project safely and in the best interests of taxpayers.

“Transport for NSW’s position remains that the contractor has not yet met the requirements to rectify the default notice issued earlier this year. Transport for NSW will continue to consider all options available under the contract and at law to protect the public interest,” the agency said.

The government has been at loggerheads with the consortium since tunnelling on the final 244-metre section of the M6 at Rockdale was stopped indefinitely by a sinkhole that opened above one of the twin tunnels in March 2024.

Days later, another emerged about 150 metres away in a construction area on the eastern side of West Botany Street.

Transport for NSW attempted to bring the dispute to a head by issuing the consortium an ultimatum to resume work by May 1 or face legal action.

The agency later rejected an offer by contractors to complete the motorway, deeming it inadequate but giving them more time to return to the table with an improved one.

Transport for NSW’s most recent target date for completing the M6 is the end of 2028, which is three years later than a previously planned opening in late 2025.

However, the M6 is now at serious risk of opening later than 2028 if the CPB-led consortium walks away from the project or the government tears up its contract and is forced to search for another builder. Even if a deal can be struck, the project faces delays to the 2028 target date and a major cost blowout.

While transport officials have maintained that there is an engineering solution to complete the tunnels, the two sides have been in a stalemate over liability for the cost of the halt to construction and the fix.

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