Revealed: Colossal cost of high-speed rail line from Sydney to Central Coast

The cost of building a high-speed train line from Sydney to the Central Coast is estimated at up to $32 billion, underscoring the challenges confronting the Albanese government if it presses ahead with ambitious plans to construct a new dedicated link all the way to Newcastle.

The cost estimates are contained in confidential modelling done two years ago by the then-Coalition state government as it considered options for building a fast rail line from Sydney northwards.

A dedicated fast rail line from a station at Sydney Olympic Park to Gosford via a stop at Epping was estimated to cost between $25 billion to $30 billion, and take up to 12 years to build once planning approval was granted, according to documents marked “cabinet in confidence”.

A render of a high-speed railway station in Australia. Credit: Federal government

Another option that involved extending the fast rail line further north to Wyong and Tuggerah was estimated to push the total bill to between $27 billion and $32 billion. The plans were never made public.

The Albanese government has since proposed plans for a dedicated high-speed line between Sydney and Newcastle to be the first stage of a new link spanning the eastern seaboard from Brisbane to Melbourne.

It was handed a business case for a high-speed rail line connecting Newcastle to Sydney last month. If it makes an investment decision to push ahead early this year, plans for the megaproject are set to become a plank of federal Labor’s election campaign.

The federal plans are for high-speed trains to travel at up to 320km/h, slashing the time for a trip from Newcastle to Sydney to an hour, a reduction in travel time of about 90 minutes. It is more ambitious than the previous state government’s plans for “fast rail”, which was for trains to travel at up to 250km/h.

The internal NSW government documents obtained by the Herald warn that building a dedicated fast rail line from Olympic Park to Gosford would be “complex to stage” despite the project not disrupting the existing railway during construction.

They outline options for a “northern corridor” but do not estimate the cost of extending a high-speed line all the way to Newcastle.

Under the previous state plans, journey times for commuters between Gosford and Olympic Park would be cut by about 55 minutes, making it a 25-minute trip.

An artist’s impression of a high-speed train operating between Sydney and Newcastle.

The base-case option for fast rail is described in the documents to have “significant reliability and capacity benefits for passenger services between Sydney and Gosford”, as well as “high urban development and wider economic benefits”.

The detailed modelling was prepared by senior NSW bureaucrats for a final business case for the northern corridor between Sydney and Newcastle.

A federal High Speed Rail Authority has since taken the lead on the ambitious plans, and favours the line’s alignment running under Sydney Harbour to Central Station, a divergence from the previous NSW Coalition government’s proposal for the main city station at Olympic Park.

High Speed Rail Authority chief executive Tim Parker said a new line from Newcastle to Sydney would be expensive, but he declined to outline the estimated cost.

“It’s a different project [to what the previous state government considered],” he said. “It’s not so much cost; it’s the benefits it generates.”

A spokesperson for federal Transport Minister Catherine King said any funding decisions for a new line would be informed by an assessment from Infrastructure Australia, which was under way.

She confirmed the federal government had received the business case from the authority for a high-speed rail line between Newcastle and Sydney.

Asked whether the federal opposition would support a high-speed line from Sydney to Newcastle, Coalition transport spokeswoman Bridget McKenzie said it was waiting on the Albanese government to provide the business case to get some idea of its cost and viability.

The federal government will need support for the project from its NSW counterpart if it is to proceed. Asked if it would support or help fund it, a spokesperson for NSW Transport Minister Jo Haylen said: “We await the High Speed Rail Authority’s final business case.”

About $79 million of the $500 million that the Albanese government has committed to plan for and protect a corridor for a high-speed rail line between Sydney and Newcastle is being spent on paying for the business case.

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