By Lynda Myer
Following that the final TBMs arrives on site, Sydney Metro West aims to build Sydney’s second under-harbour railway crossing. Running from The Bays, under Sydney Harbour, to Hunter Street in the Sydney CBD, the 2.3-km twin tunnels will be exvacated by these two TBMs, while it is a part of the Sydney Metro West – Eastern Tunnelling Package (ETP) and has been granted to the John Holland, CPB Contractors (CPB) and Ghella joint venture (JCG JV). These are the last of six TBMs being used for tunneling on the 24-km Sydney Metro West line.
In the previous month the TBMs arrived in 32 pieces by ship (16 for each TBM) at White Bay port last month and their current location is inside the 34-m-deep station box at The Bays being assembled ahead of their commission later this year.
The journey path of both 1,100 t machines is due to be parallel to the Anzac Bridge, heading to the new Pyrmont Station site, and then under Darling Harbour before reaching the Hunter Street Station site in the heart of the CBD.
In order to digging through sandstone and beneath the harbour, these mixed shield (slurry) TBMs are specifically designed and this will be the second under harbour crossing undertaken by Sydney Metro using this technology following the successful crossing between Blues Point and Barangaroo as part of the City & Southwest project.
The average advance of TBMs following their launching will be at the rate of 90 m per week and are going to arrive at the Hunter Street Station site in mid-2025. Sydney Metro West is expected to be complete by 2032.
