4,000-tonne tunnel boring machine, Bella has taken the next step to start tunnelling for Transurban ‘s $6.7 billion West Gate Tunnel project.

Last week, Bella’s cutterhead was lifted into the launch site and is now being attached. When assembled, Bella is 90 metres long and 15.6 metres in diameter – as tall as a five-story building.

Together with her sister TBM, Vida, they 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.

How do TBMs work?

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

The TBMs will use their giant cutting heads to burrow through soil and rock, while progressively installing a watertight concrete lining behind them to create the new tunnels.

Why are the TBMs named after Bella Guerin and Vida Goldstein?

Naming digging equipment after women is a tradition that dates to the 1500s when miners prayed to St. Barbara to keep them safe underground. 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.

Bella Guerin was the first woman to graduate from a university in Australia in 1883. Guerin went on to obtain a master’s degree in 1885, took up a career in teaching and campaigned for women’s rights and anti-conscription during World War I.

Vida Goldstein started her campaign as a young woman, helping her mother, Isabella Hawkins; a suffrage campaigner from Victoria. Goldstein was instrumental in getting equal rights for women, helping win the right to vote for Australian women.

Once complete, the West Gate Tunnel will cut travel times from the west by up to 20 mins with the tunnels connecting the West Gate Freeway to the port, city and Citylink.

Construction of the West Gate Tunnel will be finished in 2022.

> Find out more about the West Gate Tunnel Project 

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