The TBM broke through a wall of rock at the new Waterloo Station in Sydney in New South Wales, Australia.
Minister for transport Andrew Constance said: “While we’re about to open Sydney Metro in the north west on 26 May, this latest milestone shows the extension of metro rail into the city is moving quickly as well.”
TBM Mum Shirl started digging from Marrickville and has since bored through about 304,000 tonnes of rock – enough to fill 47 swimming pools – and installed 1,815 concrete rings to form the tunnel.
Mum Shirl is one of five TBMs building the 15.5km twin railway tunnels between Chatswood and Marrickville.
Two TBMs are working on 8.1km of twin metro tunnels from Marrickville to the new Sydney Metro station sites at Waterloo, Central, Pitt Street, Martin Place and on to Barangaroo, where they will be removed from deep underground.
TBM Mum Shirl will spend about two weeks at Waterloo undergoing planned maintenance before being relaunched through the opposite end of the station box towards Central Station.
The TBM is named after an Aboriginal woman who dedicated her life to her community, raising 60 foster children.