Green Line Extension to Mystic Valley Parkway (Route 16)

Alignment

The extension would carry the Green Line’s Medford Branch about 0.9 miles beyond its current terminus at Medford/Tufts (College Avenue), running northwest beside the MBTA Lowell Line through the Medford Hillside and Tufts neighborhoods. It would end at a new Mystic Valley Parkway station (also called Route 16) on the Medford–Somerville line. About 10,000 people live within a 10-minute walk of the site.

The MBTA’s 2017 design called for shifting the existing commuter rail tracks to make room for two light rail tracks, rebuilding the Winthrop Street and North Street bridges, and building a single ground-level island platform with a terminal headhouse. There would be a pickup and drop-off area on Boston Avenue and bicycle parking, but no car parking.

Route 16 was the preferred terminus in the early Green Line Extension (GLX) plans. The Conservation Law Foundation, whose 1990 Big Dig settlement led to the GLX, says the state committed under Gov. Deval Patrick to go all the way to Route 16. The state split it off as a second phase in 2009 and opened the rest of the GLX in 2022 at a cost of $2.3 billion. Route 16 has no funding source, no current cost estimate, and no construction timeline.

Updates

2022-12 — Medford Branch opens, with renewed calls to finish the line

The Medford Branch opened on December 12, 2022, with Medford/Tufts as its terminus. At the opening, the Conservation Law Foundation urged MassDOT to assess the costs and benefits of extending to Route 16 and hoped the incoming Healey administration would back a study. Medford Mayor Breanna Lungo-Koehn said the city was already pushing for the extension and an environmental study.

2022-05 — Left out of the MBTA’s five-year capital plan

The capital plan approved in late May 2022 did not include the Route 16 extension. MBTA General Manager Steve Poftak had said earlier in the year that it was still in the “planning and permitting phase” and faced a “funding hurdle.”

2017-11 — Lower-cost redesign enters new state environmental review

In October 2017 the MBTA filed a Notice of Project Change with state environmental regulators for a one-mile extension along the Lowell Line right-of-way with a ground-level terminal station. MassDOT and the MBTA said a fresh review was warranted because of the time elapsed and neighborhood changes since 2009. The new review was to examine traffic, noise, vibration, and effects on three properties on the National Register of Historic Places. No funding source or construction timeline was identified.

2016-05 — Regional funding moved to rescue the main project

After GLX cost overruns, the Boston Region MPO began moving the $190 million planned for Route 16 into the main project: about $158 million programmed for FFY 2016–20, plus $32 million in FFY 2021. The money was later reallocated. MassDOT committed to start environmental review of the Route 16 phase by the end of 2016, but said it had no commitment to fund construction.

2012-06 — MPO programs money for the Route 16 phase

The MPO had placed $185 million in flexed highway funds for the Route 16 phase in its long-range plan for 2016–2020. In June 2012 it approved a transportation improvement program with $8.1 million for design, which opponents warned would commit it to roughly $190 million in construction. In 2009 the state had put the cost at about $130 million.

2009-10 — Route 16 deferred to a second phase

The GLX draft environmental report moved the planned Medford Hillside terminus to College Avenue and deferred Mystic Valley Parkway to a future phase, citing cost. The 2010 final report kept the deferral.