Progress Resumes on Green Line Extension Project

The plan to extend Green Line light rail service to Somerville and Medford is getting back on track after the project stalled last year because of significant cost overruns, a setback that inflated the cost estimate from nearly $2 billion to as much as $3 billion and caused the state to put construction on hold and re-evaluate the project design, procurement, management, and funding.

A B Line Green Line train sits on the tracks at North Station. Several people stand on the platform.
In the wake of these cost escalations, the MassDOT Board of Directors and the MBTA’s Fiscal and Management Control Board (FMCB), now overseeing the project, assigned an interim project management team to redesign the project by scaling back design elements to reduce costs while maintaining the anticipated benefits and functionality of the original project concept.

The team presented its findings to the boards this spring and offered various means to save costs, including minimizing the use of retaining walls (which would affect the design of the Community Path bicycle trail that would run along the new Green Line corridor), building open-air stations rather than enclosed ones, and constructing a smaller vehicle maintenance facility.

The pared-down design was presented as a starting point for working out the details of the design work going forward. In May, the joint boards voted to take next steps to advance the scaled-back project. The decision to recommit to the project’s advancement was bolstered by financial commitments to the project made by the Boston Region MPO, the Cities of Somerville and Cambridge, and developers with interests in the new Green Line corridor. The MPO’s commitment will ultimately leverage $190 million in funding ($152 million of the MPO’s federal discretionary funding and $38 million in matching funds from local contributions). The cities and developers have pledged $75 million.

The MassDOT Board and FMCB are now engaging with the Federal Transit Administration (FTA), which holds the purse strings of a nearly $996 million federal New Starts grant awarded to the Commonwealth for the Green Line Extension. (Access to those grant monies remains frozen since the project was paused.) Under the Commonwealth’s original agreement with FTA, that grant would be matched by approximately $1 billion of Commonwealth funds.

The MPO’s $190 million commitment is a reallocation of monies that were previously devoted to a future second phase of the extension of the Green Line. The first phase would extend the Green Line from Lechmere Station in Cambridge through Somerville to end at College Avenue in Medford, near Tufts University; the second phase would extend the line from the College Avenue Station to a terminal station at Route 16 (Mystic Valley Parkway) in Medford.

During public discussions that aired at the MPO meetings this spring, MPO members heard testimony from many supporters of the Green Line Extension project. Municipal leaders and legislators representing the communities in the new Green Line corridor were among those advocating for the MPO’s continued commitment to construct a station at Route 16. Supporters have cited the economic development potential in the corridor, the opportunities to build new housing and provide transit access to jobs, and air quality and health benefits that would come from reducing auto usage and enhancing bicycle and pedestrian connections to transit service.

In response to the sustained interest in the full extension to Route 16, MassDOT made a commitment to the MPO to begin the environmental review process for the second phase by the end of calendar year 2016, and to carry out the Massachusetts Environmental Protection Act (MEPA) process through to the completion of a Final Environmental Impact Report, as long as the first phase of the project continues to advance. With this assurance, the MPO voted unanimously on June 16 to approve the transfer of funds from the second phase to the first phase, as documented in Amendment Four of the FFYs 2016-20 Transportation Improvement Program (TIP).

The MPO formalized the decision by incorporating the transfer of funds into the Long-Range Transportation Plan (LRTP), Charting Progress to 2040. Details are available in Amendment 1, which can be accessed here. The MPO voted to approve Amendment 1 at the August 18 meeting.