“People will start to feel a much more consistent, smoother, reliable trip, giving people time back in their day,” Eng said at a meeting of the MBTA board’s safety subcommittee. “What we are proposing today and what we’re going to deliver on is a new way of doing business.”

The plan builds on the success of the T’s 16-day shutdown of the Red Line between the JFK/UMass and Ashmont stations and the entire Mattapan trolley line last month, which eliminated all slow zones — more than two dozen in total — and made trips much faster.

And the plan marks a promise kept by Eng, who vowed on his first day as head of the agency in April to provide the public with a schedule for when the T would make repairs to eliminate each speed restriction.

To be sure, the effort is a huge undertaking for an organization that has struggled to deliver on even its most basic duty in recent years: to provide safe, reliable transit service.

But it signals a fundamental shift in the T’s approach to its infrastructure problems. The T has long opted to slow down trains over faulty areas instead of making much needed repairs in a timely fashion. Even as the Federal Transit Administration admonished the T for failing to properly maintain its tracks last year, the agency repeatedly declined to provide the public with information about its slow zones, keeping secret the extent of the problem. Only in February did the agency begin to publish data about the zones.

The upcoming shutdowns will include segments of all four subway lines, starting with the Green Line, which the T plans to shut down between North Station and Kenmore Station from Nov. 27 to Dec. 5 and between Riverside and Kenmore stations from Dec. 11 to Dec. 20. The T had previously announced that it would close the Orange Line between Oak Grove and North Station this weekend and the Red Line between JFK/UMass and Park Street stations the weekend of Nov. 18-19.

Eng said the plan will involve “short-term pain for long-term wins.” Alternative travel options are still being finalized, the T said, and may include accessible shuttle bus service and increased service on other modes.

“We’re maximizing these outages to minimize the impact moving forward for the public,” Eng said. “We know how diversions can impact people’s lives. But we also know if we give enough advanced notice, people can find ways around them.”

Transit advocates celebrated the plan Thursday.

“This is exactly what the riding public has been calling for for years now,” said Stacy Thompson, executive director of LivableStreets Alliance. “It’s not a sexy plan, but it’s a very practical, reasonable way to go about repairing tracks.”

If the T can successfully repair the tracks, it will be a welcome change, especially for Orange Line riders who endured a month-long shutdown of the entire line last summer, only to see it result in slower trains.

Making matters worse for riders, wait times for trains and buses remain higher than before the pandemic, and T ridership still remains well below pre-pandemic levels. On the subway, average weekday ridership in September was about 50 percent of what it was in September 2019.

Since Eng took over, he has promised to restore service and get rid of slow zones, but the T has struggled to eliminate the zones more quickly than it adds new ones. Dysfunction within the T’s Maintenance of Way department, which oversees track safety, has complicated efforts, according to reports released by the agency in September, along with a series of troubling incidents this year in which trains came dangerously close to hitting track workers.

The Maintenance of Way failures resulted in a huge spike in slow zones on the subway system in March when T leadership realized it had not been documenting and addressing the defects correctly.

Maintenance of Way workers responsible for checking subway infrastructure for defects either didn’t understand their responsibilities or didn’t fulfill them and, as a result, missed defects on vast swaths of the subway, reports by an outside expert hired by the T and the agency’s safety department showed. Many workers in charge of inspecting the system’s tracks didn’t have enough experience or training, the expert said.

The MBTA’s new chief of infrastructure, Doug Connett, one of several new T executives brought on by Eng last summer, will lead the track repair program, Eng said. Hiring new talent has been key to putting together the plan, Eng said.

Sam Zhou, the T’s chief engineer and another new executive brought on by Eng, said the agency plans to eliminate 152 speed restrictions next year and has scheduled work on 188 days in 2024, though work schedules may shift.

The Red Line is expected to see the most service disruptions next year, with 67 days of work beginning on Feb. 5 when nine days of repairs are planned between the Alewife and Harvard stations, according to the tentative schedule.

The T has set aside 58 days for work on the Green Line, which is tentatively set to begin Jan. 3 with 10 days of suspended service between North Station and Kenmore, extending on the E branch to Heath Street and on the B branch to Babcock Street.

The longest single stretch of suspended service is scheduled to unfold over 18 days on the Green Line beginning on Feb. 20. That’s when the T plans to do track repairs between Copley and St. Mary’s Street on the C branch. Repair work will also be done on the B branch to Babcock Street, and on the C branch to Brookline Hills.

There are 39 days of work tentatively scheduled for the Orange Line beginning March 18 with a three-day service suspension between the Haymarket and Jackson Square stations. Four more Orange Line service closures are expected each month between next May and October.

On the Blue Line, the T plans to suspend service for three days in April between Airport and Wonderland stations. Work is also expected to be done between the Bowdoin and Airport stations, but the T hasn’t specified any service suspensions for those repairs and indicated on its tentative schedule that the work would be completed overnight when the system is closed.

Also on Thursday, Eng announced service disruptions in downtown Boston to accommodate the dismantling of the Government Center Garage by HYM, a private developer, are winding down.

Eng said the T has reached an agreement with HYM to finish work that has required the agency to suspend subway service near the construction site.

HYM will do the work over 20 days when the T will be suspending Green Line service to repair tracks and eliminate slow zones. The first installment will unfold over nine days tentatively scheduled to begin on Nov. 27, and the last part of the work will be completed over 11 days, Eng said.

After that work is completed, there will be no further service disruptions due to the dismantling of the garage, Eng said.