A 12km underground rail tunnel from Bayswater to Forrestfield floated by Treasurer Troy Buswell yesterday has been described as nothing more than a thought bubble and a distraction.
As he dealt with the fallout of dumping the State Government's commitment to having its $2 billion MAX light rail running by 2018, Mr Buswell said he was "very seriously considering" building the Government's $1.9 billion airport and Forrestfield heavy rail underground.
Mr Buswell announced the light-rail project would be put on hold for three years so the Government could focus on delivering its other big transport promise - the Forrestfield line, which will now operate two years later than promised in 2020 - as he delivered the Government's mid-year economic review on Wednesday.
Mr Buswell said 4km of the airport rail link was always going to be underground and making the full length of the Forrestfield line a tunnel could be better value for money.
"What the project team are now saying to me is one of the options they are very seriously considering is continuing that tunnel from the airport precinct under the river, through to link up with the railway line at Bayswater," he said.
"There are a heck of a lot of benefits to the broader travelling public by not building a railway line down the middle of the Tonkin Highway.
"If that presents as a value option, then it's something we would do. If it's not a value-for-money proposition, then of course we are not going to do it, but given the tunnel-boring machine will be there anyway . . . it would be silly of us not to make those investigations."
Mr Buswell made the comments at the opening of the pedestrian underpass at Perth station, where he and Perth Lord Mayor Lisa Scaffidi cut the ribbon on the final stage of the Perth City Link rail project six months early.
Curtin University professor of sustainability Peter Newman said the tunnel plan would be much more expensive - eight to 10 times more than building it above ground - and could not be taken seriously.
"It's like a young engineer has come up to the Transport Minister at a cocktail party and asked if he's considered a tunnel to the airport," Professor Newman said. "WA has a proven record of building rail down the middle of a freeway - we do it well - so it makes sense we would take the line down the middle of Tonkin Highway from the Midland line to Great Eastern Highway."
Opposition Leader Mark McGowan said he did not believe the Government was even considering building the rail tunnel the full length of the line. "This is another thought bubble by the Government and it has about as much honesty as their promise to build a railway to Ellenbrook," Mr McGowan said.