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Improved Travel Times and Reduced Congestion Through Public Transportation

MBTA Green Line Extension (GLX) Project | Boston, Massachusetts

The Massachusetts Bay Transportation Authority (MBTA) broke ground for the new Green Line Extension (GLX) at the future site of Union Square Station in Somerville, MA. The GLX Project will extend the Green Line northwest approximately 4.7 miles and create a one-seat ride to downtown Boston, eliminating the need for bus and rail transfers. Approximately one mile will run on the Union Square Branch to a new Union Square Station in Somerville and the other 3.7 miles will run on the Medford Branch to College Avenue in Medford. Seven new stations will be constructed as part of the project as well as a new vehicle storage and maintenance facility in Somerville.

Sponsor: Massachusetts Bay Transportation Authority (MBTA)

Project Type: Transit (Rail)

Image shows train car from the MBTA Green Line.
Seven new stations will be constructed as part of MBTA's Green Line Extension project. Source: MBTA.
This pie chart shows $72.6 million CMAQ funding, $995 million federal funding, and $1,301 local funding as a proportion of the total $2,297 million project funding.
Pie chart demonstrating the primary sources of funding for the MBTA Green Line Extension project.


VOC 2.24 kg/day
NOx 1.73 kg/day
CO 88.11 kg/day


Map showing a segment of the current MBTA Green Line train route and planned extension with station locations.
Seven new stations will be constructed as part of MBTA's Green Line Extension project. Source: MBTA.

Disclaimer: The U.S. Government does not endorse products or manufacturers. Trademarks or manufacturers' names appear in this presentation only because they are considered essential to the objective of the presentation. They are included for informational purposes only and are not intended to reflect a preference, approval, or endorsement of any one product or entity.

Updated: 03/25/2020
Updated: 3/25/2020
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