Work on Sydney’s first new road harbour crossing in more than 35 years is powering ahead, with the first of two giant tunnel boring machines set to reach the halfway point in its journey from Birchgrove to Waverton this week.
At the other end, hidden beneath Waverton, the excavation of two enormous underground chambers is now complete, marking another major milestone for the Western Harbour Tunnel project.
The chambers will serve as the final destination for the two tunnel boring machines, which are carving out the final 1.5-kilometre stretch of tunnel beneath Sydney Harbour.
Once the tunnel boring machines complete their journey around 50 metres beneath the harbour, they will break through into the purpose-built chambers, connecting the new tunnels with the already excavated 2.8-kilometre section stretching from Cammeray to Waverton.
Measuring up to 23 metres high, 35 metres wide and 34 metres long, the chambers are an engineering feat in their own right, providing enough space to safely dismantle the largest tunnel boring machines ever used in the southern hemisphere.
Constructed using specialised roadheader machines, the chambers have been designed to allow the tunnel boring machines’ massive cutterheads and shields to be detached, moved sideways and permanently sealed into the surrounding rock.
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.
Western Harbour Tunnel remains on track to open to traffic in 2028 and will remain in public hands. Once opened it will reduce traffic by:
- 35% on the Western Distributor
- 20% in the Sydney Harbour Tunnel
- 17% on the Sydney Harbour Bridge
To follow the progress of the tunnel boring machines, visit the Western Harbour Tunnel TBM Tracker
Minister for Roads Jenny Aitchison said:
“The Western Harbour Tunnel is taking shape deep beneath Sydney harbour, and these two major milestones show just how much progress is being made on this once-in-a-generation project.
“As the first tunnel boring machine is reaching the halfway point beneath the harbour, crews on the North Shore have completed two enormous underground chambers ready to receive these engineering giants.
“These chambers are up to 23 metres high and 35 metres wide. It’s hard to comprehend the scale of what our crews are building beneath the streets of Sydney.
“When the tunnel boring machines break through next year, it will mark another extraordinary achievement in delivering Sydney’s first new road harbour crossing in more than 35 years.
“Every metre of tunnelling brings us closer to giving motorists another way to cross the harbour, taking pressure off existing routes and building a more connected, resilient Sydney.”
