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admin | Created: 22 May 2015 | Updated: 22 Feb 2018
GEOSTRATA, 2015, May/June, 68

In March, Seattle Tunnel Partners began to hoist “Bertha” – the tunnel-boring machine (TBM) on the Alaskan Way Viaduct project – to the surface to begin repairs. The TBM was brought to the surface in four parts, with Bertha’s cutterhead and main drive unit as the fourth and final lift. If all goes well, boring could resume in August 2015. An animated, narrated video of the repair plan is posted at