This boring machine named ‘Mum Shirl’ started digging from Marrickville on 5 November 2018.
It is estimated the machine has carved through about 304,000 tonnes of rock, opening a 3.1-kilometre tunnel in six months.
‘Mum Shirl’ is one of five tunnel boring machines on the Sydney Metro project that were designed, built and delivered by German manufacturer, Herrenknecht.
John Holland and Ghella, the partnership that won the $2.8 billion contract, purchased the five boring machines from Herrenknecht which were built specifically for the conditions of this job.
The five machines will build the 15.5-kilometre twin railway tunnels between Chatswood and Marrickville.
‘Mum Shirl’ will spend two weeks at Waterloo Station to undergo planned maintenance and will then be relaunched at the opposite end of the station box, towards central station.
Sydney Metro says machines that work underground on major tunnelling projects around the world are typically given female names.
The name ‘Mum Shirl’ references an indigenous Australian woman who dedicated her life to the Redfern community, close to the site of Waterloo Station, raising 60 foster children.
Two other machines are currently working on 8.1 kilometres of the tunnels from Marrickville to the new Sydney Metro sites at Waterloo, Central, Pitt Street, Martin Place and onto Barangaroo, where they will be removed from deep underground.
The first tunnel boring machine broke through at Waterloo in April 2019.