Online ExclusivesExcavation to Reach World's Largest Tunneling Machine Complete Excavation to Reach World's Largest Tunneling Machine Complete Excavation crews have reached the 120-foot depth needed to repair Bertha. By Cory Dellenbach February 02, 2015 Filed Under Washington Tunneling Machine Excavation Sign Me Up! Join your colleagues who already get great content delivered right to their inbox. Sign up Digital! If you don't want to bring your iPad into the bathroom, we can send you a magazine subscription for free! Subscribe to Print! The world’s largest tunneling machine, Bertha, is lowered into a pit at the start of the tunneling project under Seattle for an underground highway. The tunneling machine broke down and needs to be repaired. Crews began excavating to its site in mid-October and finally reached the bottom of the pit on Jan. 30. The Washington Department of Transportation announced Jan. 30 that the 120-foot-deep tunneling machine repair pit in Seattle is complete. Approximately 20,000 cubic yards of material was removed from the ground over the course of the excavation, which began in mid-October,... Please login or register to view Dig Different articles. It's free, fast and easy! Popular Stories April 25, 2024 How Much Ventilation Does Your Confined Space Need? April 25, 2024 From One-Facility Startup to Thriving Utility Solutions Across the Nation April 25, 2024 A Complacent Attitude Can Put Your Safety on the Job at Risk April 25, 2024 Product Focus: Utility Locating, Surveying, Safety and Education April 25, 2024 Success Stories: Utility Locating, Surveying, Safety and Education April 25, 2024 Training Tools Are Available to Improve Crews Discussion Comments on this site are submitted by users and are not endorsed by nor do they reflect the views or opinions of COLE Publishing, Inc. Comments are moderated before being posted. Please enable JavaScript to view the comments.