A proposal has been put forward in Brisbane in Queensland, Australia for new underground highway links. The proposal has been put forward by Brisbane City Council. The first project would be for the new North West Motorway, which would link Carseldine-Bald Hills with Stafford Kedron.
This new highway will provide a major extension to the city’s network of underground highways, should the project get the go ahead. The construction project is likely to be significant in scale should it go forward and the estimated cost could be in the region of US$6.57 billion to US$9.75 billion (A$9.5 billion to A$14.1 billion).
A second underground road tunnel costing $5.39 billion to $7.95 billion (A$7.8 billion to A$11.5 billion) meanwhile would connect Brisbane Airport with Indooroopilly. This would be an 11km stretch, with completion due as far away as 2041. The project would include facilities for Bus Rapid Transit and the Brisbane Metro.
There are still discussions as to whether the routes should be free for use or tolled. If free for use, close to 110,000 vehicles/day would be expected to use the North West Motorway while if tolled, around 61,000 vehicles/day would be anticipated.
The work is needed as Brisbane suffers heavily from traffic congestion and further growth in population and vehicle numbers are anticipated in the future. Although an early proposal for the North West Motorway had suggested building the link on the surface, environmental factors have now ruled against this option due to the presence of protected species along the route.
Should the proposals be accepted, the approval process will still be lengthy and the financing required to deliver such a mega project will be extensive.