The upcoming shutdown of the Orange Line will send hundreds of shuttle busses and thousands of cars onto streets and highways, carrying people who used to ride the MBTA.
"We already know that Boston's traffic is back to pre-pandemic levels, and that's bad because we were ranked #1 in terms of congestion," said Rick Dimino, president and CEO of A Better City and Boston's former transportation commissioner.
Many who live and work in neighborhoods along the Orange Line, like Kapioalani Kassel, are worried.
"I'm really concerned about all the parking," she said. "Parking already is such an issue for everyone, so like, the Orange Line literally has thousands of people. It's how they get in and out and now with driving and traffic. The traffic's already awful."
Get Boston local news, weather forecasts, lifestyle and entertainment stories to your inbox. Sign up for NBC Boston’s newsletters.
Chiara Haskell has seen rail service be suspended before.
"I was impacted when the Blue Line had its weeks' shutdown, just because that was kind of annoying, so I'm kind of expecting the same type of issues with the shuttles being inconsistent, things like that," she said.
More on the MBTA
But the magnitude of this shutdown is unprecedented for the MBTA.
"This is not very common at all," said Keith Millhouse, a national rail safety expert. "Typically, you don't see this type of neglected maintenance on systems that you have to shut down the entirety of a system of a one-month period of time."
This shutdown comes at a time of increased demand for transportation as people return to the city from vacation or to go back to school. There is talk of creating pop-up bus lanes for the shuttles, but Dimino says that's easier said than done.
"Negotiating a bus lane is not something you do in pop-up-like fashion, because it affects residents and small businesses, and that's usually a pretty deep and serious dialogue regarding the impacted community," he said.
The looming shutdown also is forcing area colleges to scramble.
"The Orange Line is our lifeline at Bunker Hill," said Pam Eddinger, president of Bunker Hill Community College. "It is pointless to bemoan the fact that we have a problem to solve."
The problems are particularly acute at Bunker Hill, where four out of five students also work, and three out of five are parents.
"We are taking this very seriously," Eddinger said. "It is what it is, we need to get this fixed, it is not a choice."
President Eddinger says her teams are already communicating with students and staff. She estimates some 85% of students and staff at BHCC rely on the Orange Line.
"We are in the education business, we have no choice but to be optimistic," she said.
Grace Abbott says traffic and parking concerns are secondary.
"I mean, I don't see how it could get much worse," she said.
"It is indicative of a systemic decay of a system over the years," Millhouse said. "I think it is unfortunate it took the FTA to do it, it should have been self-initiated by the MBTA so it could be planned better and not just dumped on people at the last minute."
Shuttle and traffic details are still being worked out. The MBTA plans a big public awareness campaign once those plans are in place.