Tunnel-borers smash through 80 per cent of new Metro West line

Tunnel-boring machines Dorothy and Betty have smashed through solid rock at Clyde on the Metro West line, with more than 80 per cent of the tunnels for the project now completed.

Tunnel-boring machines Dorothy and Betty have smashed through solid rock at Clyde on the Metro West line, meaning more than 80 per cent of the tunnels for the project have now been completed.

The machines have carved out 5.7 kilometres of tunnel since starting at Sydney Olympic Park in September last year, averaging around 200 metres of tunnel each week.

The 24-metre underground junction cavern, while not a Metro station, will connect the tunnels with the above ground stabling and maintenance facility, where the network’s new train fleet will be housed.

Tunnel Boring Machine (TBM) Dorothy has broken through into the junction caverns at the base of the Clyde Dive site. Picture: supplied

Betty arrived at the underground site at Clyde in December, spending seven weeks traversing the cavern before continuing on to Parramatta. Dorothy completed the twin tunnels breaking through the rock wall late last month.

The machines will continue to Parramatta, which is one of 10 proposed stations on the 24km line between Westmead and the Sydney CBD, including a potential additional station at Rosehill. They will need to carve out a further 1.1 kilometres before reaching the future Parramatta Metro station site by the middle of the year.

Tunnel Boring Machine (TBM) Dorothy has broken through into the junction caverns at the base of the Clyde Dive site. Picture: supplied.

The breakthrough at Clyde means the tunnels have now been laid for more than 80 per cent of the Metro West line, with Dorothy and Betty removing 1.1 million tonnes of material and installing more than 41,000 precast concrete segments to line the walls.

Premier Chris Minns said the sooner the new Metro West line was up and running, the more houses could be built, helping alleviate Sydney’s housing shortage.

“This is another huge step forward as we deliver the largest new public transport project Western Sydney has seen in generations while also turbocharging the delivery of new homes,” he said.

“These fast and reliable new metro services will double capacity between the Sydney CBD and Parramatta and will be a gamechanger.”

Originally published as Tunnel-borers smash through 80 per cent of new Metro West line