Clearing Those Clogged Arteries

Boston drivers, a notoriously freewheeling breed, find their ultimate frustration on the city's Central Artery. Twice each weekday, for a total of seven hours, it becomes a virtual parking lot. The highway, a six-lane stretch of Interstate 93 that snakes through Boston's downtown section from the Massachusetts Turnpike to the Charles River, handles 180,000 automobiles a day -- nearly 2 1/2 times its stated capacity. The two-mile elevated section, built without any shoulders or slowdown and speedup lanes for exits and entrances, has an accident rate that is twice the average for urban highways in the U.S. Next year Massachusetts will begin a ten-year, $4.3 billion project to rebuild and reroute some seven miles of highway, including Central Artery. Construction will add four traffic lanes, enough to accommodate an anticipated 210,000 vehicles a day, and will replace the elevated roadway with a tunnel. But Transportation Secretary James Burnley sternly criticizes the underground portion of the project for not adding enough capacity.