On 14.01.2015 the fourth TBM, named Maria after 19th century Aboriginal rights advocate Maria Lock, started boring for North West Rail Link in Sydney, Australia. The 900 t TBM was delivered to the Cherrybrook site in 18 shipping containers and 27 large pieces, and was assembled by more than 70 engineers.

All four TBMs are now at work on Australia’s longest railway tunnels – twin 15 km tunnels from Bella Vista to Epping. TBM1 Elizabeth, named after colonial pioneer Elizabeth Rouse, has dug more than 1.8 km of tunnel so far from Bella Vista; TBM2 Florence, named after Australia’s first female architect and engineer Florence Mary Taylor, has dug more than 710 m from Bella Vista; and TBM3 Isabelle, named after Isabelle Andersen, aged four, to represent all the tunnelbuilders, has dug more than 150 m from Cherrybrook. Along with TBM3 Isabelle, TBM4 Maria will dig 6 km from Cherrybrook to Epping at around 120 m/week, mostly through Sydney sandstone and shale.

The North West Rail Link is currently scheduled as opening in the first half of 2019. Click here and au/11 for tunnelbuilder archive. Visit http://nwrail.transport.nsw.gov.au/. 04/15.