The Boston Central Artery/Tunnel project would seem to be a textbook case of a megaproject gone off the rails: Projected to cost $8 billion, the "Big Dig" ended up at $14.6 billion. The original seven-year schedule doubled, numerous indictments were handed up, and an accident killed a motorist.
The 2006 deadly collapse of 10 tons of precast-concrete ceiling panels in the I-90 connector tunnel, which killed a vehicle passenger, is the project's one, literally fatal flaw. Otherwise, the long-term positive effects are clear, say many.