We are building twin tunnels between the Maribyrnong River and the West Gate Freeway, providing a vital alternative to the West Gate Bridge. The project will ensure quicker and safer journeys and remove over 9,000 trucks from streets in the inner west.

The tunnels are being built using two tunnel boring machines (TBMs) so the community and businesses can continue above ground while work happens below ground.

How do TBMs work?

Tunnel boring machines (TBM) use the latest tunnelling technology and are custom designed and built to suit ground conditions in Melbourne’s west.

TBMs operate like moving underground factories, using their giant cutting heads to burrow through soil and rock. The two TBMs on the West Gate Tunnel Project, named Bella and Vida, will burrow 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 on 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

Why are our TBMs named after 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

Specialised training for the West Gate Tunnel Project has now also started for more than 30 tunnel workers with a hyperbaric chamber installed onsite so workers learn about operating in pressurised conditions.

Workers will work up to 35 metres below ground level and will need to spend up to two hours depressurising before returning to the surface. Up to 20 people will work in the TBM at any one time.

Hyperbaric chamber training equipment

Where is 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.