Video: Changing cutting tools on Bertha TBM

This is a great video showing the application of ground freezing to deep excavations in unstable soil and high groundwater table.  It’s also a nice overview of the reason the Hetch Hetchy project was undertaken, […]

A TBM named for Eliza Leggett, an active participant on the underground railroad, and later a suffragist, has been tunneling for the past 6 months on the massive I-75 reconstruction project in metropolitan Detroit. The […]

The massive 13-mile wastewater tunnel project known as Brightwater is approaching the final stretch of tunneling, but perhaps the most difficult. This portion of the project has already claimed one contractor’s slurry TBM and put […]