Two tunnel boring machines (TBMs) are ready to commence the Westgate Tunnel Project in Melbourne. Their names are Bella and Vida.
The TBMs were named for good luck in the project ahead. According to the Westgate Tunnel Project website, this tradition dates right back to the 1500s, when miners and military engineers who excavated with explosives prayed to Saint Barbara for protection.
The names reference two ground-breaking Australian women. 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 campaigner for women’s rights, establishing the right for females to vote and stand for election.
The TBMs have been lowered and assembled 22m below ground in Yarraville and will start tunnelling soon.
A massive shed was recently built in Yarraville to handle the 1.5 million cubic metres of rock and dirt excavated by the machines.
As Bella and Vida start digging, the rock and dirt they extract will be moved along a conveyor into the shed. This conveyor will be 15km long by the time tunnelling is finished.
Bella will dig the 4km outbound tunnel first, followed by Vida, who will dig the 2.8km inbound tunnel. The longer tunnel will take around 18 months to complete.
The TBMs require constant cooling as they bore their way through rock and soil. Lakeside Cooling Towers is providing the vital water cooling on a 24/7 process.
Lakeside has supplied MA30 induced draft cooling towers for Bella and Vida, and has assisted in the design and supplied the 5m raised platform, 100m³ storage tanks, circulation pumps and automatic dosing equipment.
The CPB and John Holland Contractors Joint Venture project is Lakeside’s second tunnel boring venture with John Holland.