Australia’s Sydney Metro Northwest has reached a tunnelling milestone after breaking through at Cheltenham.
The AU$8.3bn (£3.7bn) project – formerly known as the North West Rail Link – is the first stage of Sydney Metro, Australia’s largest public transport infrastructure scheme.
Tunnel boring machine (TBM) Maria has so far tunnelled more than 4km, with 380,000t of crushed rock excavated along the way.
The TBM has been digging an average of 120m a week, mostly though Sydney sandstone and shale.
Maria, one of four TBMs being used for the project, has now completed almost 75% of the journey from Cherrybrook to Epping.
Tunnelling works are expected to be complete in 2017 and Sydney Metro Northwest is scheduled to open in 2019.