Metro or heavy rail? The two options on the line for Sydney train extensions

Running double-deck or driverless metro trains on potential rail extensions to Sydney’s outer south-west from the new city of Bradfield near Western Sydney Airport is under consideration.

The opening of the city-section of the major M1 line under Sydney Harbour between Chatswood and Sydenham two weeks ago has triggered renewed interest in metro rail extensions, and raised questions about plans for fast-growing parts of the city ill-served by public transport.

A metro line between St Marys and Bradfield via Western Sydney Airport is due to open in late 2026.Credit: Wolter Peeter

Transport Minister Jo Haylen told a budget estimates hearing that extensive studies into potential rail extensions from Bradfield to Leppington and Glenfield, or to Campbelltown and Macarthur, were “mode agnostic”, and are considering both heavy rail and metro options.

“This is a mode-agnostic study because we want to make the best decision for the future of those communities and for our integrated public transport network,” she said on Tuesday.

Coalition transport spokeswoman Natalie Ward questioned the minister about whether the Rail Tram and Bus Union’s opposition to more spending on metro lines was part of the decision-making.

Haylen said the government would not be making decisions about public transport investment based on ideology, which she accused the previous Coalition government of doing.

“We’ll be making decisions based on evidence and based on need,” she said.

The union has urged the Minns government to scrap the troubled conversion of a 13-kilometre stretch of heavy rail line between Sydenham and Bankstown to metro train standards, arguing that is “nonsensical for Labor to continue to pursue metro lines at the expense of heavy rail in Sydney”.

It has called on NSW Labor to improve transport in the state by prioritising heavy rail.

The state government is also working on a business case for a metro extension between St Marys and Tallawong, where it would connect to the existing M1 metro line.

Under questioning about whether it could also be heavy rail or metro, Haylen said $40 million had been allocated to develop a business case for a metro connection between St Marys and Tallawong.

The government has made no commitment for extensions to the $11 billion metro rail line under construction from St Marys to Bradfield via the new Western Sydney Airport beyond funding business cases to investigate them.

In the lead-up to the state election early last year, Labor pledged to work on business cases for an extension of the airport metro line from Bradfield to Macarthur, and northwards from St Marys to Tallawong.

However, it ditched the previous Perrottet government’s plans to proceed with business cases to connect the new airport line to a Metro West station at Westmead, or an extension of the problem-plagued Metro Southwest from Bankstown to Glenfield.

Sydney Metro chief executive Peter Regan told the hearing that he expected the business cases for the potential northern and southern rail extensions to be completed within about 12 months.

“The priority focus is to identify corridors, to identify station locations, to identify the mode and to be able to start developing up options,” he said.

The agency is working with Transport for NSW on the business case for the southern extensions from Bradfield because they were more complicated.

Transport for NSW secretary Josh Murray said he expected to be in a position to be able to review the options for rail extensions by the end of next year, and enter discussions with government.

The state and federal governments are each chipping in $50 million for the south-west Sydney rail study.

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