History has been made deep under the heart of Sydney’s CBD with the first mega tunnel boring machine (TBM) arriving at the new Pitt Street metro railway station.
TBM Nancy broke through a wall of rock at the site of the future Pitt Street Station, about 20m below the streets of Sydney.
Nancy, one of five TBMs, had already tunnelled six kilometres since launching in October.
Since launching from Marrickville last year, Nancy has excavated about 600,000 tonnes of rock – enough to fill 14 Olympic swimming pools.
At Pitt Street Station, it has taken tunnel builders John Holland CPB Ghella nine months to remove about 92,000 tonnes of sandstone to build the underground station cavern in preparation for TBM Nancy’s arrival.
The 150 metre long TBM will now undergo maintenance before being re-launched towards the future Sydney Metro station at Martin Place then on to Barangaroo.
TBM Mum Shirl is a few hundred metres behind Nancy, building the twin tunnel along the same route.
All the crushed rock from Sydney Metro tunnelling will be reused, with some of it going to help build the new Western Sydney International (Nancy-Bird Walton) Airport.