Tunnel boring machine (TBM) Millie has reached a significant tunnelling milestone, arriving 12m below the bed of the Yarra River on the way to the new Town Hall Station.
Hot on Millie’s heels is TBM Alice, which launched a few weeks after Millie to dig a parallel tunnel from the Anzac Station site.
The TBMs will take around 2 weeks to cross under Melbourne’s iconic waterway. They will then travel a further 300 metres under Swanston Street to complete the final section of tunnelling in the east.
Tunnelling for the project is now 85 per cent complete, with 3 of the 4 TBMs now on their final legs towards Town Hall Station. TBM Joan is on the way from State Library Station in the west, and TBM Meg will start digging in parallel to Joan in coming days.
The arrival of all 4 TBMs at Town Hall Station later this year will mark the end of tunnelling for the Metro Tunnel’s twin 9km-long, 6.3m-high tunnels.