Construction
Details
- Year Started
- 2017
- Year Completed
- 2022
- Project Elements
-
- Light rail
- Maintenance facility
Overview
This design-build Light Rail Transit (LRT) project extends the existing Green Line LRT alignment by 4.7 miles along two operating branches with both branches beginning at the relocated Lechmere Station in Cambridge. The Medford branch mainline extends 3.7 miles north to College Avenue in Medford and the Union Square branch line extends one mile west to Union Square in Somerville. The project included clearing and grubbing, demolition of 31,337 feet of old freight track, 362,400 cubic yards of excavation within an active rail corridor, approximately 17 miles of track constructed – 45,755 feet of LRT track, 12,670 feet of maintenance yard track, and 28,098 feet of commuter rail track, 47 pieces of special trackwork, one mile of combined viaduct structures requiring 22 million pounds of steel girders, six new at grade stations and one aerial station, a 55,000 square foot four-bay Vehicle Maintenance Facility (VMF) and a 1,509 square-foot Transportation Building used as the GLX control center, six modified or reconstructed bridge structures, 263,174 square feet of sound and retaining walls, three traction power substations (TPSS), an overhead catenary system (OCS) with 795 poles, an Automatic Train Control (ATC) system, and a 1.8-mile community pathway. The entirety of the LRT project was constructed within the right-of-way of the Massachusetts Bay Transportation Authority (MBTA) Lowell and Fitchburg commuter rail lines. Live track work was coordinated with the MBTA, Amtrak, and Pan Am Railways.