Harding and Smith on board for Green Line extension

Some thirty years after the Commonwealth pledged to extend the Green Line to Medford and Somerville as part of an agreement concerning the Big Dig, trains are finally clacking north beyond the Lechmere station. GBPCA contractor Harding and Smith has been along for the ride for the past eight years of the bumpy project’s starts and stops.

When the MBTA first put the project out to bid in 2014, the Walpole-based contractor won a lot of work, including pumping stations and HVAC installations. The initial plans for the extension included full-featured, enclosed stations boasting glass exteriors and artwork on display inside. Estimated costs began rising and continued to spiral to $3 billion, however, causing the state to stop the project before major work began. It nearly killed the extension altogether.

In 2017, the state developed a scaled-down project with open-air stations and a budget of $2.3 billion. GLX Constructors, a consortium of construction and design companies, took over as the general contractor. Harding and Smith re-upped for the modified project, which called for less work than the extension’s original vision.

“It’s really a tale of two projects for us,” says Mike Perrotta, Harding and Smith’s estimator and project manager. One of the contractor’s crews has been handling track drainage, while another has been installing dry standpipe for fire protection. Most of the work has focused on the viaduct that extends from Lechmere to East Somerville.

Local 12 members Joe Chicos (L) and Corey Elliott work on the GLX project for Harding and Smith.

As Perrotta explains it, the southern portion of the Green Line extension is so congested, the fire department wouldn’t be able to have full access to the elevated trackway.

“We’re putting fire pump truck connections on the street level where they can get at them,” he says. “Farther north, it’s not needed because fire crews have more leeway to reach the tracks.”

For the track drainage work, the contractor’s plumbers are installing piping to collect water that will accumulate on the tracks during heavy rains. They are directing some of it down to concrete splash blocks and tying the rest of the piping to underground drainage systems. Without the mitigation, water would spill over the sides of the elevated track and cause havoc below.

“Local 12 and Harding and Smith have been fighting for roadway and track drainage work for years,” Perrotta notes. “It requires the skills of plumbers.”

The Green Line extension project is unique for the contractor, because it requires workers to be elevated most of the time.

“With everyone working off manlifts, manlift experience is important,” says Perrotta. “They have been working anywhere from 10 to maybe 40 feet off the ground, in difficult climate conditions, while navigating trains, high voltage power lines, and construction equipment near them.”

Because most of the pipe can’t be picked up manually, rigging has also been an important skill. Towards the end of the project, when test trains began running or maintenance trains needed to pass (part of the project includes a new railyard and maintenance facility near the extension), MBTA or Keolis flag persons were working closely with the construction trades workers to clear the area and ensure safety. Some sections of the extension are also located near commuter rail tracks, which added to the complexity of the project.

Originally scheduled to open in late 2021, the long-brewing extension was further delayed by complications from COVID and supply chain issues. The branch which runs to Union Square Station in Somerville is ready to roll. The Medford branch, which includes five stations and terminates at College Ave. Station near Tufts University, is set to open later in the spring. The original plans called for extending the Green Line all the way to Route 16. A later phase may include additional track and another station.

“The extension is a great project for the corridor that runs through Cambridge, Somerville, and Medford,” Perrotta says. “It’s good for smart development, reducing traffic, and reducing carbon emissions.”