Construction of the Melbourne’s West Gate Tunnel has progressed with the arrival of the first of two massive tunnel boring machines (TBMs) at the Port of Melbourne.

Known as Bella, the first TBM is approximately 90m-long, 15.6m-high and weighs 4,000t.

Due to its large size and weight, Bella was dismantled into 100 of parts in China and is being transported to Australia to complete the tunnel digging work.

To create the tunnel, workers will operate as deep as 35m below ground level. They will work on depressurising for two hours before returning to the surface. Up to 20 people will work with the TBM simultaneously.

“The six-lane twin tunnel will run under Yarraville between West Gate Freeway and Maribyrnong river.”

Named Vida, the second TBM is expected to reach Melbourne in approximately eight weeks.

Being constructed with A$6.7bn ($4.82bn), the six-lane twin tunnel will run under Yarraville between West Gate Freeway and Maribyrnong river.

Once operational in 2022, the tunnels are intended to reduce congestion on residential streets, cut traffic pressure along the M1 corridor from Pakenham to Geelong. Sorry, there are no polls available at the moment.

The project is likely to provide a boost of approximately $11bn to the Victorian economy. It is also expected to create nearly 6,000 new jobs.

With the design updates, the tunnel is expected to improve city connections, create new open spaces and more cycling paths, as well as other improvements.