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Milestone reached on Melbourne’s ‘missing link’ route with order for tunnel boring machines

The construction of the longest road tunnels ever built in the Australian state of Victoria has come closer to start with the order of the two tunnel boring machines (TBM) to deliver the confirmed works.

The two 15.6m diameter Herrenknect tunnel boring machines will be used to dig the 6.5km long twin-bore tunnels for Melbourne’s North East Link road, which has been described as a missing link in the Melbourne road network. town. The completion of the 26km toll road between the M80 and the Eastern Motorway is expected to ease congestion with journey times reduced by 35 minutes and remove 15,000 lorries from the local road network.

The North East Link will feature longer sections of tunnel than originally planned following the public consultation process.

The tunneling works will be carried out by the Spark Consortium, formed by Capella Capital, China Construction Oceana, CPB Contractors, Dif, GS Engineering and Construction, John Laing, Pacific Partnerships, Ventia and WeBuild. The consortium was awarded the A$11.1bn (£6.37bn) contract to deliver the tunnel late last year.

The tunnel boring machines – each weighing 4,000t and measuring 90m in length – will be used to take the link under the Yarra River, up to 40m underground. The machines are expected to be delivered to the project site on the north side of the river in 2024 to begin the route south.

The TBM launch site will form the north portal of the tunnel when the project is complete

Preparation work for the launch of the tunnel boring machines is already underway with the start of work to relocate the Yarra East main sewer and construction enclosures. The TBMs will be launched from a 200m long excavated box on the east side of Greensborough Road, where site leveling is underway ahead of piling work later this year.

Work is also underway to manage excavated materials from the project. Waste will be removed from the launch site using an elevated enclosed conveyor system above Greensborough Road where it will enter an acoustic shed to be loaded onto covered trucks for removal from site.

The entire North East Link project is expected to be completed in late 2027 or early 2028.

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