Seattle tunnel

Workers prepare a gravel pad as a massive crane is used to lift a 2,000-ton section of the tunnel boring machine known as "Bertha" in March 2015. The project was stalled for two years as engineers struggled to repair the gigantic machine.

National

Bertha Is Finally Breaking Through In Seattle

12:03pm April 04, 2017

by Martin Kaste

After a two-year delay for repairs, the giant tunnel-boring machine is on the verge of completing its mission far beneath the city's streets.