The Western Harbour Tunnel project has reached another major milestone, with its second tunnel boring tunnel (TBM) now carving a path towards Sydney Harbour.
Launched 44.7 metres below Birchgrove Oval, the tunnel boring machine – named Barangaroo – has begun excavating the final section of the twin motorway tunnels between Birchgrove and Waverton.
Barangaroo joins its sister TBM, Patyegarang, which started tunnelling last month. Together, the pair will excavate the final 1.5-kilometres beneath the Sydney Harbour and complete the last stage of tunnelling for the 6.5-kilometre Western Harbour Tunnel.
At 15.7 metres in diameter and weighing 4,350 tonnes each, the two tunnel boring machines are the largest ever assembled underground, and the largest to be used in the Southern Hemisphere.
As they advance, they will install around 13,000 pre-cast concrete segments and 1,300 20-tonne culverts manufactured at a dedicated facility in Emu Plains.
During the launch process, Barangaroo will construct the first three tunnel rings, each using ten of the 15-tonne segments, before pushing through the launch chamber wall and starting her journey.
Named after prominent Aboriginal women and adorned with Indigenous artwork, Patyegarang and Barangaroo will operate around the clock and reach depths of up to 50 metres below sea level.
The tunnelling comes as another key milestone, the Berry St on-ramp in North Sydney on the other side of the Harbour, nears completion.
The future connection will link motorists to the WestConnex via the Rozelle Interchange, bringing the project a step closer to transforming the way motorists travel across Sydney.
Mechanical and electrical fit out is progressing, including lighting, traffic monitoring cameras and signage that will support the tunnel’s safe operation when it opens.
The Western Harbour Tunnel remains on track to open to traffic in 2028, and will reduce traffic by:
- 35% on the Western Distributor
- 20% in the Sydney Harbour Tunnel
- And by 17% on the Sydney Harbour Bridge.
It will remain in public hands.
You can track the TBMs progress here
Minister for Roads and Regional Transport Jenny Aitchison said:
“Today marks another exciting milestone for the Western Harbour Tunnel project, with Barangaroo now beginning its journey beneath Sydney Harbour.
“With both tunnel boring machines now in action, we are making strong progress on the final stage of excavation for this important Harbour crossing.
“It’s taken extraordinary feats of engineering to get to this point, and the teams who’ve assembled and launched the TBMs entirely underground have done an outstanding job.
“Once complete, the Western Harbour Tunnel will provide a seamless connection between the Warringah Freeway at North Sydney and WestConnex at the Rozelle Interchange, improving travel across Sydney’s motorway network.
“The Western Harbour Tunnel remains on track to open in 2028, and we can’t wait for motorists to experience what it has to offer.”