Train service on the Ashmont branch of the Red Line resumed on Monday morning to positive reviews from passengers and T officials, who hailed a 16-day October “surge” to make track and station improvements as a success.

“The MBTA is proud to have successfully completed this critical work on an expedited timeline. As a result, Red Line and Mattapan Line riders are now experiencing safer, faster, and more reliable service,” said Phillip Eng, the MBTA general manager. “I want to thank the public for their patience as we completed critical infrastructure work along the Ashmont Branch and Mattapan Line over the last 16 days.”

According to Eng, work crews replaced 5,000 of rail on the subway line between Ashmont and JFK-UMass while the train service was suspended between Oct. 14-29. Another 4,700 feet of rail was replaced along the Mattapan Hi-Speed trolley line right-of-way. Thousands of wooden ties that serve as the railway foundations were also replaced. The improvements were aimed at eliminating 38 “slow-zones” on the Ashmont branch— which were in place due to safety concerns related to the aging infrastructure. Eng had promised that the surge would address that speed issue—resulting in commutes that could be up to 10 minutes faster for the 40,000-plus people who rely on the branch on a typical weekday. On Monday, commuters and operators along the line signaled that, in fact, they did benefit from faster, smoother rides on the trolleys and train cars.

Eng himself took a ride on Monday from Mattapan Square to Ashmont and on to South Station. In a video released by T officials, Eng engaged with customers, one of whom agreed that the Red Line service had noticeably improved. “Yes, this reminds me of the old Boston,” the man observed. “The old Boston is the new Boston now,” Eng replied.

“Hopefully it stays like this,” the passenger replied.

Eng answered: “It will. We’re going to keep improving.”

There were also improvements made inside stations during the shut-down. At JFK-UMass, workers installed new floor tiling, repaired stairways, changed LED lightbulbs, added new paint, and power washed platforms. Other work was completed at Shawmut, Fields Corner, Ashmont, and Savin Hill stations, along with Mattapan. The result, said Dennis Varley, the MBTA’s chief of stations, are stations that are noticeably brighter and cleaner.

“We only had the 16 days, but when there’s diversions we’re going to jump on them. In a perfect world, we want to have everything in a state of good repair so that you don’t need a surge . But, right now, we have to catch up.”

Although the heavy-duty disruption is over for Ashmont and Mattapan riders, there are other diversions and weekend work coming up on the Red Line in November. Last week, the T announced that shuttle bus service will replace Red Line trains between Alewife and Kendall-MIT stations this coming weekend, Nov. 4-5, to focus on track improvements there, also with an eye towards alleviating speed restrictions.

And, there will be two targeted diversions this month between JFK-UMass and Park Street to make fixes between Broadway and South Station, which is another slow zone that Eng and his team want to speed up. Buses will replace trains between Tues., Nov. 14 and Thurs., Nov. 16 between 8:45p.m. and end of service; another diversion will take place for the entire weekend on Nov. 18-19 between JFK-UMass and Park Street.