About the Green Line Extension (GLX) Project

Bulldozer levels ground for GLX track

GLX Construction is Underway

For detailed project information, visit the MassDOT GLX Project page.

  • Sign Up for Alerts

  • City Presentations

  • Background & Planning

Sign Up for City Updates About the MassDOT GLX Project


The idea of extending the Green Line to Somerville is by no means a new concept. As early as the 1920s the Metropolitan Planning Commission considered the possibility. Numerous studies promoted the plan over the next decades. In 1990, Massachusetts agreed to extend the Green Line to offset the pollution increase within Somerville caused by the Big Dig. Despite this legal commitment, however, the Green Line Extension project lagged far behind schedule, prompting the City of Somerville and the Conservation Law Foundation to file a lawsuit to keep the project moving. In 2006, this litigation, with the help of community support and advocacy groups such as Somerville Transportation Equity Partnership (STEP) and the Union Square Task Force, finally brought about a multi-million dollar state investment in the Green Line extension from Lechmere Station into Somerville and Medford.

Planning Process

Community involvement played a large role in the initiation and planning of this project. A Public Advisory Group, consisting of representatives from Somerville, Medford, and Cambridge, provides guidance and input to the Executive Office of Transportation and Public Works.

Additionally, STEP, the Somerville Transportation Equity Project, has been involved throughout the process, ensuring that the extension will result in social equity, environmental health, and decreased population to improve the health of Somerville residents.

Past Community Correspondance