Green Line Extension (GLX)

The Green Line Extension (GLX) project extends the existing Massachusetts Bay Transportation Authority (MBTA) Green Line D branch of service to the north from Lechmere Station in Cambridge into Somerville and Medford, Massachusetts. This project is expected to support a ridership of more than 50,000 passengers. 

The scope of work for the 4.3-miles of tracks along the two branches involved, the construction of six new ADA compliant T stations, the demolition and reconstruction of the Lechmere station, and the construction of a new vehicle storage and maintenance facility. Also part of the GLX Project is a 1.9-mile multi modal community path running alongside the railway. Linking the existing community path in Somerville with result in the shared use path to cross over the Somerville Boston Engine Terminal “BET” by viaduct (requiring ten piers and two abutments) and connect with the Cambridge Grand Junction Multi-use Path. Ultimately these paths connect four of the GLX Stations; Lowell Street, Gilman Square, Washington Street, and Lechmere.

As a part of the Construction Management team on this Design-Build contract, Techno provided inspection services and construction management services. Working within the existing railroad right-of-way, construction impacts were minimized despite challenges to planning and staging. In close proximity to residential areas mitigation measures to reduce noise and vibration impacts were necessary as well as additional Covid-19 precautions. Techno staff submitted progress reports, inspector’s diaries, daily records, Request for Information (RFI), and verified estimates and specifications.