Experts’ blunt message for the royal commission: ‘The Big Build must stop’

November 4, 2026 — 5:00am

Pressure is mounting on Opposition Leader Jess Wilson to expand her promise to “pause and review” the Suburban Rail Loop to all Big Build rail projects, as the royal commission considers evidence that multibillion-dollar investments were tainted by political interference and compromised planning decisions.

A confidential submission to the Big Build commission by a group of the state’s most experienced rail engineers, design consultants and planning experts calls for work to cease on the $34.5 billion SRL, the $13 billion Melbourne Airport Rail Link and the $4.1 billion Sunshine Super Hub until an independent review is conducted and fresh business cases published.

Their call comes as the state election is officially under way. Premier Ben Carroll visited Governor Margaret Gardner on Tuesday to issue the writs for what he described as the most consequential electoral contest in Victoria’s history.

The 25-day formal campaign period, which will run through to the close of polls on November 28, was only a few hours old when the Reserve Bank of Australia lifted the official cash rate to an 18-year high.

The confidential submission to the royal commission, which is due to hold its first public hearing on Monday, argues that each of these major rail projects are the product of a “deeply flawed, whimsical” selection process, non-compliant with the requirements of the state’s Transport Integration Act and not supported by credible business cases.

“It is our view that the Suburban Rail Loop, the Melbourne Airport Rail, the Sunshine Super Hub (recently renamed Airport Rail stage 1) and the Big Build must stop,” the submission reads.

“Before changes to these projects or any future projects are enacted, an independent, open and peer-reviewed program must be completed and a business case provided to the public.”

A separate, scathing submission to the Big Build royal commission by William McDougall – an independent transport planner who worked on the West Gate Tunnel, North East Link, Suburban Rail Loop and the airport rail link – urged the inquiry to tackle a deeper, cultural problem within Victoria’s approach to major projects.

“Worthwhile outcomes do not excuse a governance system in which announcement precedes analysis, dissent is discouraged, and accountability is weakened,” he said. “Such a system increases the risk of selecting inferior projects, misallocating public funds, suppressing professional advice and creating conditions in which misconduct can flourish.

“I believe Victoria needs a governance system that selects initiatives because they solve demonstrated problems and provide enduring public value, not because they offer short term political advantage.”

McDougall urged Victoria’s next government to restore independent public service advice, transparent analysis, enforceable statutory duties and continuous external scrutiny to the state’s major infrastructure program.

The Age this week reported allegations contained in a submission to the royal commission by an experienced Transport Department planner that cost estimates were doctored and a senior public servant threatened with the sack to bake in the case for the state government’s politically preferred route for the airport rail link.

Carroll, speaking on Tuesday shortly before visiting Government House with his wife, Fiona, and their daughter Maddie, said he was not aware of the allegations until he had read about them in The Age.

He insisted that, despite the questions this raised about the integrity of the Melbourne Airport Rail Link (MARL) business case, the project needed to be built. “Airport rail is in the public interest,” he said. “Victorians need it and deserve it.”

Wilson, when asked if she would pause and review the airport rail project along with the SRL, said people had already waited too long for it to be delivered.

“Under this term of the Labor government, we have seen it kicked out time and time again,” she said. “The contracts have been signed, the works are under way. We will deliver this.”

Wilson, who is entering the campaign proper with a commanding lead in published opinion polls, was last week forced to clarify her long-standing promise to “pause and review” the SRL, saying that work would continue on the line between Box Hill and Cheltenham while a review was conducted.

The royal commission has been told that a secret working group was formed within the Department of Transport in late 2017 or early 2018 to bolster the case for the Andrews government’s preference to run a future airport rail link though Sunshine rather than a more direct route.

The most serious allegations are that cost estimates were deliberately inflated for a more direct route, known as the Maribyrnong route, by exaggerating by 3.5 kilometres the distance of tunnelling required, and that a public service executive was threatened with dismissal if the working group failed to back the case for Sunshine.

Former premier Jacinta Allan, the minister responsible at the relevant time for public transport and major projects, has described the allegations as incorrect. She is expected to be called as a witness by the royal commission, which is being led by former chief justice of South Australia Chris Kourakis.

The Age also revealed this week that a market-led proposal to build an airport rail link along the Maribyrnong route at no cost to taxpayers was rejected by senior government officials without the plan being considered by the cabinet.

The 2015 proposal was put forward by a consortium that included Melbourne Metro Trains, the operator of the city’s metropolitan train network, and financial services giant IOOF.

University of Melbourne School of Engineering emeritus professor Colin Duffield said both sides of politics needed to be open to market-led proposals. “If you take a level playing field, you would hope that the private sector can bring expertise and a hard-edged robustness to some of the decisions and expenditures that maybe government can’t take,” he said.

The most contentious part of the current plan for the MARL, which was delayed for several years amid a protracted dispute between the government and Melbourne Airport over the location of the airport station, is $4.1 billion of works planned in and around Sunshine station.

The so-called Sunshine Super Hub project, which does not have a published business case, involves complex grade separations of metropolitan, regional, airport and freight tracks running in and out of the western suburbs rail hub.

The project, which was initially conceived as part of a Western Rail Plan to provide more frequent and faster rail services to the city’s fast-growing western suburbs and regional areas, was rebadged by the Andrews government as a section of the SRL, and more recently, as the first stage of the MARL.

Along the way, provision for a new rail tunnel between Southern Cross Station and Sunshine station – a critical element to provide greater capacity regional and metropolitan trains into the city – was quietly dumped, causing rail experts to question the purpose of the mega-project.

Carroll and Wilson have both promised to build a new Keilor East railway station as part of the airport rail link, despite it adding significant cost to the project and travel time for people travelling between the airport and the CBD.

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