For years now, we’ve heard what an engineering triumph the Big Dig is. We are supposed to marvel at its complexity, and hail the skill of those who put it together.
Now, that may all be warranted. But, for some reason, I can’t help but think about the Callahan and Sumner tunnels, and all those century-old tunnels used by the subway system. They’ve worked from the day they opened, and I can’t think of a structural disaster that’s ever befallen any of them.
So why is the Big Dig so different?