Construction on the new Assembly Square Orange Line stop in Somerville, which has already begun, will lead to periodic bus diversions on the subway line beginning in June and lasting until the station is complete in fall of 2014.
Most bus diversions will take place on weekends or at night, according to a presentation given by MBTA officials at a community meeting in Somerville Wednesday night.
Community College, Sullivan Square, Wellington, Malden Center and Oak Grove stations will all see bus diversions at some point during construction.
Terry McCarthy, a project manager with the MBTA, said the first weekend bus diversion is tentatively scheduled for June 9, although that date is not yet set in stone.
In the beginning, diversions will be "sporadic," McCarthy said, but by late summer and early fall they'll be more regular.
Orange Line passengers should expect two types of bus diversions: Weekend diversions, which will start at 9 p.m. on Fridays, and "early access" diversions, which will take place between 9 p.m. and the end of service on weeknights.
During these diversions, buses will replace Orange Line trains between various stations. McCarthy said the diversions will affect different stations at different times depending on the work being done.
A new station
The MBTA is in the process of building the Orange Line station—the first new MBTA rapid transit station to be built since 1987—in the Assembly Square area of Somerville. It will be between Wellington and Sullivan Square stations, and it will serve the new , which is also under construction.
Construction on the station is expected to take 33 months, and the station is projected to be open by fall of 2014, according to Wednesday's presentation (Workers will still be putting finishing touches on the station after it opens.)
The project will begin with moving the southbound track out of the way in order to build the center platform, according to Wednesday's presentation. Workers will then construct platforms and station structures before laying down a new southbound track. They'll complete work by putting finishing touches on the station.
According to Wednesday's presentation, held at the , the MBTA will notify riders the Monday before weekend diversions, and they'll post notices in stations and leave "seat drops" on trains. Riders can also learn about diversions on mbta.com.