The Australian state of New South Wales is planning to build a three-lane tunnel and reverse the direction of an existing tunnel as part of the M5 motorway expansion plan.

The state is also planning to build the first stage of the road linking the proposed M4 East with the M5 in the city’s inner west.

The state government will spend an estimated A$1bn ($847m) to connect the two projects, according to

The state is looking at raising the traffic volumes in the M5 corridor during peak morning hours to 6,376 by 2021 from 5,246 vehicles in 2006.

The entire project, which may be funded through toll collection, is expected to cost A$4bn ($3.3bn) and is scheduled for completion by 2016.