See what it’s like to dig a tunnel 100 feet below a city

by acdangeron 7/11/23, 2:58 AMwith 1 comments
by Terr_on 7/11/23, 3:25 AM

Over here in Seattle, this reminds me--even down to the scrolling javascript stuff--of other features about the "Bertha" digging machine for the I-99 tunnel project, which replaced an earthquake-risk viaduct.

Comparing stats, both project are a similar distance, but the highway involved removing about 23 times more material as it went. (57.5-foot diameter hole vs 12.)