Sumner Tunnel to close for repairs starting July 5

the Sumner tunnel will be closed for a month starting July 5, state transportation officials announced tuesday, to allow for more repairs of the 90-year-old structure.

the closure, which will last half as long as originally planned, follows two years of weekend closures and a twomonth shutdown of the tunnel last summer that brought major traffic headaches to the area. When the tunnel reopens after this summer’s one-month closure in early August, weekend closures will continue until at least october, and possibly until thanksgiving, said Highway Administrator Jonathan Gulliver.

the tunnel carries about 40,000 vehicles a day from East boston, under the harbor, and into downtown, according to massDot.

“We strongly encourage travelers to plan your trips and use public transportation as much as possible,” said Gulliver.

the adjacent Callahan tunnel, which carries vehicles in the opposite direction, from boston’s North End to East boston, will remain open throughout the summer.

Gulliver acknowledged the closure of the Sumner tunnel will cause major traffic problems in East boston, including at logan international Airport, but officials said it is the fastest way for the renovation to be completed safely.

“i’d recommend anybody who is going to the airport to allow a lot of extra time to get there,” Gulliver said. “You should expect heavy traffic especially on those heavy travel days. but even if you’re traveling off peak hours, you should expect heavier-than-normal traffic.”

While they worked well last summer, the alternative detour routes will be adjusted to incorporate lessons learned during the previous closure, officials said.

During last summer’s twomonth closure of the tunnel, the mbtA provided more frequent service on the blue and orange lines and free or discounted fares on the blue line, commuter rail, nearby buses, and the ride paratransit service, and ferry. the agency estimated at the time that the mitigation efforts would cost the agency $6.1 million.

mbtA General manager phillip Eng said the same benefits will be in place during this summer’s closure, including fare-free service on the blue line, free or reduced ferry rides and commuter rail rides on the Newburyport/rockport line, fare-free service on some buses in Chelsea and some paratransit trips, and discounts on parking at some mbtA lots.

the agency spent about $7 million on mitigation efforts for the tunnel closure in 2023 and expects to spend around $3.5 million on this summer’s measures.

Since last summer, the Department of transportation has not answered questions about whether the state will reimburse the mbtA for those costs.

on tuesday, Secretary of transportation monica tibbitsNutt said the agency is still “working through that.” She said she could have an answer about whether or not the mbtA would be reimbursed in the “next few months.”

the mbtA is facing an estimated $628 million operating budget deficit come July that is expected to balloon to nearly $900 million by 2028. Neither Governor maura Healey’s funding proposal for the upcoming fiscal year nor the massachusetts House of representatives’ proposal provide enough funding to close the mbtA’s projected budget gap.

Adding services during state highway projects has historically cost the mbtA and contributed to the agency’s financial troubles. According to recent board presentations by the agency, the t will be paying off its debt for mitigation activities until 2041 for another major highway project: the big Dig.

During last year’s two-month Sumner tunnel closure, the mbtA estimates that 10 percent of the 40,000 diverted drivers opted to take public transit instead of drive, while 77 percent drove on different routes and 14 percent did not travel. transit saw the biggest influx of riders on the weekends of the closure, when blue line ridership increased 13 percent, orange line ridership went up 23 percent, and Newburyport/rockport commuter rail ridership jumped 41 percent.

this summer’s closure will be half as long, thanks to progress made during weekend shutdowns this spring, said Gulliver, and will focus on the surface of the road inside the tunnel.