Victoria will pour around $1.7 billion of public money into the tollway and road widening project. Mr McDougall was auditing aspects of the business case being developed to justify this proposed public expenditure. An artist's impression of the Footscray Road elevated freeway section of the West Gate Tunnel. Credit:Victorian government So alarmed was Mr McDougall by what he believed to be the weak economic case for Transurban's toll road that he personally contacted state treasurer Tim Pallas to raise his concerns. He told the Senate inquiry he contacted the treasurer directly after unsuccessfully raising his concerns within the transport department. "I raised my concerns at a higher level and it was about a week after that I was unexpectedly taken off the project," Mr McDougall said.

Asked by inquiry member Senator Janet Rice from the Greens who he had raised these concerns with, Mr McDougall said: "I had a direct conversation with the Victorian Treasurer Tim Pallas, who I knew professionally from previous work." Treasurer Tim Pallas. Credit:Penny Stephens Mr McDougall has a wealth of experience in the Victorian transport bureaucracy over the past two decades, working for both sides of politics assessing big transport projects including an early study of the East West Link and the Metro Tunnel project. He was due to give open evidence at the Senate hearing on Thursday. An artist's impression of the West Gate Tunnel.

But Labor senator and inquiry chairman Chris Ketter​ agreed to the Victorian government's request that most of Mr McDougall's evidence on Thursday be kept secret. Mr McDougall was allowed to give only a short public testimony before most of his evidence was heard by senators behind closed doors. He told the public part of his hearing that he and another expert employed to review the project, New Zealand transport planner and strategist John Allard, "were both extremely concerned" about both the economic and transport modelling behind Transurban's proposed motorway. Fairfax Media contacted Mr Allard in New Zealand on Thursday. He declined to comment, saying his advice to the state government was confidential. Mr McDougall said that the recent release of the environment effects statement for the road indicated that the issues he had raised with Mr Pallas had not been altered since he was removed from the project.

The Andrews government's environmental assessment hearings on the road begin later this month. Fairfax Media asked Mr Pallas' office about Mr McDougall's statements to the Senate inquiry on Thursday afternoon. A government spokesman said: "This project stacks up and we're getting on with it." He said the government had considered "extensive" modelling when developing the business case. It showed a return of $1.30 for every $1 invested. Opposition roads spokesman Ryan Smith said there were growing concerns the West Gate Tunnel project would do little to combat road congestion. He said Thursday's testimony should make Victorians "very concerned" about how Daniel Andrews was spending public money. Transurban chief executive Scott Charlton also appeared at Thursday's hearing and confirmed that the West Gate Tunnel project only stacked up because of the estimated $1.7 billion in direct funding Transurban would get via the Andrews government.

"Our proposal is a package," Mr Charlton said, arguing it was impossible to consider the project at all unless all elements of funding for it were included. Loading The Greens' Janet Rice said all independent peer reviews of the West Gate Tunnel project and the complete unredacted business case should be made available immediately. "It's important that as much information as possible is made public because it's the public's transport system after all," Senator Rice said.