The 24km Sydney Metro West project has achieved a slew of tunnelling milestones, including the arrival of two mega tunnel boring machines (TBMs) at Sydney Olympic Park.
TBM Betty, named after Olympic champion Betty Cuthbert, was first to arrive at Sydney Olympic Park in June and was followed by TBM Dorothy, named after human rights activist Dorothy Buckland-Fuller, on 29 July.
The TBMs spent 10 months completing the 4.6km tunnels from Clyde to reach Sydney Olympic Park.
TBMs Betty and Dorothy have excavated approximately 857,500 tonnes of material, to complete the first leg in the journey and have installed more than 32,600 concrete precast segments to line the new tunnel walls.
In the coming months, the TBMs will be disassembled, lifted out of the station box and transported on trucks back to Clyde, where they will be relaunched in the opposite direction towards Westmead.
TBM Betty has already returned to Clyde, while TBM Dorothy’s disassembly is ongoing. Both TBMs are expected to arrive at Westmead in mid-2025.
The focus at Sydney Olympic Park will now shift to the opposite end of the 200-metre-long, 37-metre-wide, and 27-metre-deep station box, where TBMs Beatrice and Daphne are due to break through in late 2024.
The project’s newest addition, TBM Jessie is tunnelling from The Bays towards the Sydney CBD. This machine has excavated 230m of tunnel since its launch in May.
The final TBM for the project is expected to begin the second under-harbour tunnel later this year.
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