The world’s largest tunnel boring machine, dubbed Bertha, has finally dug its way into daylight:
Almost four years after it embarked on the job, on April 4th, the 80 million dollar machine finished its 1.75-mile journey that began July 2013. Tunneling operations were initially scheduled for completion in October 2014, putting this phase of the project 29 months behind schedule. The delay is primarily attributable to about two years of repairs after Bertha broke down in December 2013.
The remainder of the nearly $3.2 billion Alaskan Way Viaduct replacement tunnel project includes highway decks, lights, connection of tunnel ramps to existing ramps and a testing period — all of which should take another year and a half.