The Big Dig



Sometimes a bridge isn’t the answer – at least not a conventional bridge, Boston had an extraordinary traffic problem that called for an extraordinary solution. The city’s six lane, elevated highway, known as the Central Artery, had become so clogged that traffic crawled along it for more than 10 hours a day.


The solution was to build an 8 to 10 lane underground expressway directly beneath the Central Artery, a road that at its northern limit culminates in a 15-lane, two-bridge crossing of the Charles River. Carrying out such a project in a city like Boston proves to be one of the largest, most technically difficult and environmentally challenging infrastructure projects undertaken in the United States.


Along with improving mobility in notoriously congested downtown Boston, the Big Dig project was conceived to reconnect neighborhoods severed by the old elevated highway.