The TBMs that will excavate Sydney’s next harbour crossing are in the final stages of assembly.
The two TBMs , which will dig the final section of the Western Harbour Tunnel, are being built in the launch chambers, measuring 28m high, 21m wide and 120m long, beneath Birchgrove Oval.
TBMs Patyegarang and Barangaroo – the largest in the Southern Hemisphere – are being reassembled using 500-tonne cranes. They will excavate 1.5km of twin motorway tunnels between Birchgrove and Waverton, up to 50m below sea level. The tunnels will be lined with around 13,000 precast concrete segments manufactured at a specialist facility in western Sydney.
Assembly of Patyegarang is 45% complete, with its 15.7m-diameter cutterhead – weighing 462 tonnes – lifted into position last week. Around 70% of the machine’s components have been transported into the launch chamber.
Patyegarang is expected to begin tunnelling under the harbour mid-year.
Assembly of Barangaroo is 20% complete. It is expected to begin tunnelling later this year.
Overall excavation across the Western Harbour Tunnel project is now 76% complete. The 6.5km tunnel is scheduled to open to traffic in 2028.
