Tunnelling has begun on North East Link, with the first tunnel boring machine (TBM) now digging the 6.5 kilometre road tunnels between Watsonia and Bulleen. It's the first of two massive machines that will help dig the twin tunnels that will take 15,000 trucks off local roads and save drivers up to 35 minutes.

Each TBM is 90 metres long, 15.6 metres high, and weighs 4000 tonnes - among the biggest in the southern hemisphere.

In keeping with tradition, TBMs are named before they start work, and the North East Link TBMs have been named Zelda and Gillian after 2 groundbreaking local women.

The late West Heidelberg resident Zelda D'Aprano AO (1928-2018) was a renowned activist, notably chaining herself to a building when an equal pay case was dismissed in 1969 and establishing the Women's Action Committee. She was a key player in a long campaign by many remarkable women working toward closing the gender pay gap.

Dr Gillian Opie is a neonatal paediatrician at the Mercy Hospital for Women in Heidelberg. Dr Opie founded Australia's first breast milk bank more than 10 years ago, providing sick and premature babies in Melbourne's neonatal intensive care units (NICU) with safe, screened and pasteurised milk.

TBM Zelda and TBM Gillian will dig approximately 10 metres per day at depths of up to 45 metres underground, building the tunnels that will pass traffic under instead of through local suburbs.

The tunnels will be built using 100% renewable electricity, and dirt and rock from the tunnels will be re-used across North East Link and other transport sites where possible with a significant amount of dirt also helping rehabilitate a former quarry at Point Wilson and the former Orica site in Deer Park.

As they excavate the tunnels, the TBMs will install tunnel walls made of approximately 44,000 individual concrete segments that have been made locally in Benalla. Tunnelling will continue into 2026, with the tunnels opening to traffic in 2028.

(From bigbuild.vic.gov.au)