The tunnel boring machines (TBMs) constructing Melbourne’s 6.5km North East Link tunnels have reached a significant milestone at the Lower Plenty Road interchange site. The two 15.6-meter diameter Herrenknecht TBMs, named Gillian and Zelda, have successfully completed a 1.6km journey from their launch site to the interchange.
Since their launch last year, the TBMs have installed over 13,500 concrete segments along their path. After breaking through into the 30-meter deep box at Lower Plenty Road, the machines will continue installing tunnel wall segments at the base of the box. They will then be relaunching underground to continue their progress toward Bulleen.
The Lower Plenty Road interchange will serve as a key access point for vehicles entering and exiting the North East Link tunnels at Yallambie.
At the Bulleen end of the tunnel route, the Yarra Link green bridge is taking shape, and tunneling continues with five large roadheaders working to break through the deep underground rock layer. Crews are also focused on major upgrades along the Eastern Freeway and the M80 Ring Road to ensure smooth connections to the tunnels.
The TBM operations are led by the Spark consortium, which includes Webuild, GS Engineering and Construction, CPB Contractors, China Construction Oceania, Ventia, Capella Capital, John Laing Investments, DIF, and Pacific Partnerships.
The North East Link is expected to be completed in 2028. As Victoria’s largest road project, it represents the largest investment in Melbourne’s north-east, encompassing not only the tunnels but also the Hurstbridge Line Duplication, the Fitzsimons Lane Upgrade, and the removal of 21 level crossings.
