Three roadheaders have met 30 metres underground in the first major breakthrough, connecting two excavated caverns that will become State Library Station.

The road headers have dug out more than 20 per cent of State Library Station, with excavation expected to be finished by late-2020.

The roadheaders have been mining station caverns and underground passenger connections under Swanston Street, near Franklin Street, for the new State Library Station.

In total, more than 500,000 tonnes of material will be excavated – the equivalent of almost 70 Olympic swimming pools – with 1,500 tonnes of rock and soil removed every 24 hours.

Seven roadheaders will be used in the CBD as part of the project – four for State Library Station and three for Town Hall Station. Each weighs 118-tonnes, is 15-metres long and is lowered underground in separate pieces, before being re-assembled underground. 

Click here and au/32 for tunnelbuilder archive. Visit https://metrotunnel.vic.gov.au/ and https://www.premier.vic.gov.au/.

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