Our two state-of-the-art tunnel boring machines (TBMs) – named Bella and Vida – will build the twin tunnels for the West Gate Tunnel Project.

The TBMs are currently being built in China and Germany, before arriving in Melbourne to start tunnelling in early 2019.

Custom built for Melbourne's west

These machines use the latest tunnelling technology and are custom designed and built to suit ground conditions in Melbourne’s west.

The TBMs will operate like moving underground factories, using their giant cutting heads to burrow through soil and rock under Melbourne’s west while progressively installing a watertight concrete lining behind them to create the new tunnels.

Each machine will weigh in at around 4,000 tonnes each and will stand 15.6 metres in diameter – as tall as a five-story building – and will be 90 metres long. The cutter heads on the front of the machines are powerful enough to spin two A380 aeroplanes a total of two revolutions per minute.

Bella and Vida will start their journey at the northern portal in Yarraville and move south-west towards the southern portals in the West Gate Freeway near South Kingsville. Work will start on the 4 kilometre outbound tunnel first, closely followed by the 2.8 kilometre inbound tunnel. The longer tunnel will take around 18 months to dig.

TBM diagram with key facts and figures

Bella Guerin and Vida Goldstein

Tunnelling tradition dictates a TBM cannot start work until it has been given a female name, a sign of good luck for the project ahead – a tradition dating back to the 1500s when miners and military engineers working with explosives, for underground excavation, prayed to Saint Barbara for protection.

Born in Williamstown, Bella Guerin was the first woman to graduate from a university in Australia in 1883 and went on to teach at Loreto Convent in Ballarat.

Vida Goldstein was a ground-breaking campaigner for women’s rights, establishing the right for females to vote and stand for election.

Working in a TBM

Working in a TBM is like scuba diving, the physical effects of working underground in compressed air is equivalent to scuba diving to a depth of 35 metres for several hours. Workers undergo specialist training to avoid ‘the bends’, using hyperbaric chambers and special equipment.

Behind the TBM, crews of up to 20 people work to build the road surface and install electrics, ventilation and safety systems.

Hyperbaric chamber training equipment

Our tunnelling hub

Our specially built tunnelling compound on Whitehall Street, Footscray, will be busy both day and night. 500 workers will help build the tunnel.

The compound includes a massive shed that will store rock and soil generated by tunnelling.

TBM sneak peek