Boston — MTBA officials have announced that the opening of the Union Square branch of the Green Line extension has been delayed twice this year. Initially, it was scheduled to open in October this year, but the one-stop line is scheduled to start operation in March 2022.

Steve Poftak, MBTA’s general manager, announced that the latest delay was primarily due to problems with the substation near the Cambridge-Summerville border. The substation converts energy and powers the Green Line Trolley at the Union Square branch. The first delay was due to supply chain issues amplified by the COVID-19 pandemic.

Terrence McCarthy, Deputy Program Manager for the $ 2.3 billion project, said there were not enough resources to complete the first substation.

“We have a crew of 650, but that’s still not enough,” McCarthy said.

Residents of Summerville said a lot of infrastructure is needed to convert the approximately 800 volts of DC power needed to operate a substation. McCarthy hopes that the 6-stop Medford branch, which was postponed from December of this year to May 2022, will also not be pushed back.

The latest delay in the 4.3-mile green line extension has tested the patience of some locals. The initial plan for the long-awaited project was made in 1991.

“I’m disappointed with the delay, but I realize that supply chain and workforce issues aren’t under the control of the project,” said Joan Johnson from Summerville. “One of the reasons we bought the house was the fact that there was a Green Line station just a few hundred feet from the front door. Recent progress has been slow, but we’ve seen trucks come back to life in the backyard. It was fun to see. “

Johnson noticed construction noise and lane mess. She looks forward to living in a quieter area.

Stacy Thompson, a resident of Jamaica Plain, believes that some of the recent complaints about the project are not entirely fair.

Thompson, Executive Director of the Livable Streets Alliance, said: “As a knowledgeable advocate who knows the details of this project, I was able to get the project on track during COVID, so I don’t have to worry about this delay.”

Thompson added that he is looking forward to the benefits of this extension for local businesses in Summerville.

“People like me didn’t travel to Summerville because commuting to the area was just a pain,” Thompson said. As soon as the project is complete, she plans to spend more nights in the area.

Working on creating fair and affordable transits in the Summerville and Boston areas, Thompson recognizes Poftak’s successful completion of the project on a new timeline within budget. Poftak specifically took over Luis Ramirez as MTBA’s new project manager in 2018.

Poftak said he would return the tens of millions of dollars that Cambridge and Summerville donated to the project.

After years of deadlocks in negotiations, locals in Summerville can finally see progress in the extension.

“I think everyone knows that the expansion will eventually happen,” said David Gibbs, who has lived near Porter Square since 1992. “At some point next spring, I’ll be running in Somerville. I’m going to take the Green Line train. — I hope I’m right. “

Gibbs believes that this expansion will be most beneficial to wealthy developers, but it also generates city tax revenues and affordable housing.

“Linkage fees and other payments negotiated by a neighboring council through a regional interests agreement will contribute to the development of additional affordable housing,” Gibbs said.

He said he believes the project could be a net plus if the city continues to guarantee that people living in Summerville can continue to live there now.

The biggest challenge for Gibbs is finding a solution for the rapid gentrification created by the new line. Earlier this year, equity analysis found that extensions offered clear benefits to non-minority riders and disproportionate benefits to non-low-income riders.

This is due to significant demographic changes in the neighborhood closest to the Green Line stop.

“Sure, many people who were here 25 years ago aren’t here now, and they won’t get any of the benefits of this,” Gibbs said. “But we want to keep the rest here and make them available for all of this new development.”