TBM Betty, operated by the Laing O’Rourke/Gamuda Australia consortium, has broken into a cavern beneath the future Westmead Station to complete her drive on the new 24km-long metro line.
The breakthrough marks completion of 93% of major tunnelling on the project.
TBM Betty spent 24 months building the tunnel from Sydney Olympic Park, via the future Parramatta Station. She excavated 790,000 tonnes of earth and lined the tunnel with 30,000 concrete segments.
The machine, named after Olympic sprint champion Betty Cuthbert, is the first to finish her tunnel at both ends of the line. Now 3.5km of tunnelling remain to complete a 30-month tunnelling programme by six TBMs.
The remaining sections are being built by three TBMs: TBM Dorothy is 1059m from her final breakthrough at Westmead, where she is due to arrive in the coming weeks. At the opposite end of the alignment, TBMs Ruby and Jessie are making their way under Sydney Harbour to reach the Hunter Street terminus in the Sydney CBD by the end of the year.
Over the next seven weeks, TBM Betty will be dismantled and lifted out of the station box.
A crew of up to 150 workers at a time have spent three years constructing the 500m underground structures at Westmead.
Along with having the deepest station on the Metro West line, at up to 39m below ground, the Westmead site is made up of a crossover cavern for future trains to switch tracks if required, a station cavern, and turnback tunnels to allow trains to turnaround to head back towards the Sydney CBD.
Sydney Metro West will double rail capacity between Greater Parramatta and the Sydney CBD. It is scheduled to open in 2032.
