The phrase 'The most successful technology is the one you take for granted.'
About says it all - Amazing achievement!

This was one of the best articles I've read on this website.! Amazing project too.

David Szondy is a very smart and a very good writer who perfectly describes engineering challenges. I wish him the best future for next coming successes fo modern technological materpieces. Thanks a lot David. I am going to forward your article to my engineers and scientists friends and colleagues. And contact me if you pass by Paris to give a talk to young engineers
Claude MASSOT Ingénieur Ecole Centrale de Paris M. Sc., Ph.D.

Very interesting and excellent article for a more excellent and interesting work done. Congratulation to the all work team. Great job done.

«If all goes to plan, the tunnel will open to traffic in 2019 – two years and over US$200 million dollars outside of plan.» Bertha had it easy - boring of the <a href="https://sv.wikipedia.org/wiki/Hallands%C3%A5stunneln">Hallandsåstunnel</a> (two parallel one-way tunnels, 8.7 km in length) here in Sweden began in 1992 and was supposed to be finished five years later in 1997, but the breakthrough did not occur until 2013 and rail traffic began first in 2015. In the end, the cost of the project amounted to some 11 times that which was originally budgeted....
Murphy's law always applies....
Henri

Lorries? You mean trucks? :)

Great article. Well researched and written.
Thanks for qualifying the title with "tunnel" boring machine, because many of us have worked on a lot of otherwise boring machines.

That was a well written, interesting article. Just enough detail without getting bogged down.

"and it struck a steel pipe that the Seattle Times newspaper said was used by WSDOT engineers to measure groundwater and had been left behind by mistake." Can you imagine being that guy? The one that was supposed to remember.

Thank you New Atlas and David Szondy for one of the most amazing articles I have read in a long time. This is truly a Man Made Wonder of the World. Thanks again for doing a first class job of writing about this project. The people of Seattle are really lucky.