Demolition on the first of three Somerville bridges being rebuilt for the Massachusetts Bay Transportation Authority’s $2.3-billion Green Line Extension was slated to begin March 23. All three vehicular bridges are scheduled to be completed by 2020, the year before the 4.7-mile light-rail extension to Medford is supposed to open.
The long-delayed project, which broke ground in June 2018, also includes seven new stations. “This is an exciting milestone for GLX,” Steve Poftak, MBTA general manager, said in a statement.