Metro Tunnel Eastern Entrance finishing touches

Work on the Melbourne Metro Tunnel’s Eastern Entrance, located in South Yarra, is almost finalised with minor works such as the William Street bridge nearly complete, landscaping beginning at Lovers Walk, and the Arthur Street pocket park and cross passages under construction.

Cross passages – which allow people and emergency services to move between the two rail tunnels in an emergency – are underway and crews have begun building an underground substation at South Yarra Siding Reserve. 

The Eastern Entrance is under construction in the South Yarra Siding Reserve and when complete, Cranbourne and Pakenham Line trains will enter the tunnel near William Street and pass under the city-bound Frankston Line and both Sandringham lines. 

The Eastern Entrance South Yarra major construction works were completed five months ahead of schedule in early 2021, including widening the existing rail corridor and excavating more than 31,000 cubic metres of rock and soil.

A base slab, internal walls and roof slab have been built using more than 7,700 cubic metres of concrete and almost 8,000 tonnes of reinforced steel. 

Victorian Minister for Transport Infrastructure, Jacinta Allan, said, “This has been a huge effort from our team – to keep this project going at a time our economy needs it most. The Metro Tunnel is one part of our massive plan to keep our growing state moving.”

In the CBD, Metro Tunnel workers are in the final stages of carving out rail tunnels within the new Town Hall Station deep under Swanston Street, as excavation for all five new underground stations nears the finishing line.

The station will be longer than a city block and as deep as a five-storey building, with direct underground links to Flinders Street Station, Federation Square and City Square.

A massive roadheader has broken through to complete the first level of the rail tunnels that will run alongside the station’s platforms and is now digging another seven metres down to complete the job. 

Over 120,000 cubic metres of soil and rock has been dug at the site by three roadheaders – enough to fill 48 Olympic swimming pools – with excavation at the station now more than 75 per cent complete.

The roadheaders have been excavating around the clock since late 2019, deep below Melbourne’s iconic Swanston Street from the corner of Collins Street to the City Square. 

The first roadheader, launched from an access shaft at City Square, began digging out the main station cavern in December 2019.

Two more were then launched to dig underground passenger connections – one from under Federation Square across Flinders Street and under Swanston Street and another from Flinders Quarter – alongside the Young and Jackson Hotel across Swanston Street to the station site.

The roadheader machines weigh around 100 tonnes and have cutterheads that can smash through rock three times harder than concrete. 

As roadheader excavation continued, the project’s four tunnel boring machines made their way between the five stations to dig twin 9km rail tunnels, finishing their journeys in early 2021. 

Work to build the station’s internal structures has also begun, with 50 massive steel support columns now encased in concrete and roof beams in place within the central cavern. 

Ms Allan said, “Focus now turns to the station fit outs, where there will be hours and hours of testing, laying the track, and getting the tunnel ready to deliver a turn up and go system we urgently need.”

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