On October 16, 2024, tunnel boring machine (TBM) Ruby began its journey to carve out the final section of the Sydney Metro West project, marking a significant step for this city-shaping infrastructure.
Launching from The Bays, TBM Ruby, named after women’s rights activist and Australia’s first radio astronomer Ruby Payne-Scott, is the sixth and final machine to work on the 24-kilometer tunnels. It will join TBM Jessie in constructing twin railway tunnels stretching 2.3 kilometres, tunnelling deep beneath Darling Harbour and into the heart of Sydney’s Central Business District (CBD).
TBM Ruby, a 1,100-ton machine, will operate continuously, inching its way alongside the iconic Anzac Bridge, through the Pyrmont Station site, and beneath Darling Harbour before arriving at Hunter Street in the CBD. TBM Jessie, launched earlier in June, has already excavated 615 meters of tunnel and installed 2,238 concrete segments. Together, the two machines will remove 460,000 tons of material and install 16,536 segments between The Bays and Hunter Street.
This section of the Sydney Metro West will form the city's second under-harbour railway crossing, complementing the first crossing between Barangaroo and the city's north, which opened in August 2024 as part of the Metro M1 line. Since then, the M1 has recorded 10 million passenger journeys.
TBMs Ruby and Jessie are mixed-shield (slurry) machines specifically designed to operate in the high-pressure conditions beneath Sydney Harbour. Parts of these TBMs were repurposed from machines used for the Sydney Metro City & Southwest tunnels. Both are expected to complete their journey and arrive at Hunter Street by mid to late 2025.
Major Breakthrough at Sydney Olympic Park
In parallel, two other TBMs, Daphne and Beatrice, recently achieved a breakthrough at the Sydney Olympic Park station site. After an 18-month tunnelling journey covering 11 kilometres from The Bays, the machines have excavated over 2 million tons of material and installed 72,456 tunnel segments to line the walls.
With tunnelling complete, work now shifts to dismantling the TBMs and preparing the 200-meter-long, 37-meter-wide, and 27-meter-deep station box for further construction. Additionally, crews will focus on building cross passages—critical safety features that allow passengers to move between tunnels in case of emergency.
The Sydney Olympic Park metro station will become a key hub, integrating with new light rail, pedestrian, and cycling routes to support seamless transportation across the precinct. It will feature an underground island platform for regular use, along with two additional side platforms to accommodate increased traffic during major events.
This development aligns with broader plans to enhance Sydney Olympic Park as a premier destination for cultural, entertainment, and sporting events. The new metro infrastructure will double rail capacity between Greater Parramatta and the CBD, significantly improving transportation options, supporting population growth, and driving employment opportunities across western Sydney. For further information on the project click here and for tunnelbuilder archive click here and au/11. Visit https://www.sydneymetro.info. 42/24.
