Nighttime commuters will face delays and detours on one of Boston’s most popular thoroughfares starting Monday as state officials close one side of Storrow Drive in downtown Boston overnight to make critical fixes to a crumbling tunnel.
Beginning at 9 p.m. Monday, and continuing for the next several months, the westbound lanes of Storrow Drive — from the Hatch Memorial Shell to Clarendon Street — will be closed during the week until 5 a.m. Later this month, repair crews will also shut down at least one lane of the eastbound artery.
Edward M. Lambert, Jr., commissioner of the Department of Conservation and Recreation, said officials are trying their best to limit the impact on Boston residents, but he still expects the closure of the 60-year-old tunnel to cause problems for commuters who depend upon the drive for getting in and out of the city.
“We understand and recognize the inconvenience, and we’re trying to mitigate the impact in terms of traffic and noise,” Lambert said. “But this project is absolutely necessary to ensure the safety of travelers through that tunnel.”
The recommended detour will take motorists north across the Longfellow Bridge into Cambridge, using Memorial Drive as the alternate route. Signs will suggest that drivers can either cross back over the Charles River at Massachusetts Avenue — or for those heading further west, at Western Avenue — where they can link up with Soldiers Field Road.
But residents and businesses in the North End and Back Bay are bracing for the impact the closure will have on their neighborhoods. Massachusetts General Hospital has contacted all employees, warning them of the possibility of delays, and Boston Emergency Medical Services is already mapping out alternate routes for ambulances.
“It’s a minor inconvenience,” said Kory Zhao, a spokeswoman for Massachusetts General Hospital. “But I don’t think it’s going to drastically affect us.”
Messages will be posted on electronic signs on Interstate 93 and the Massachusetts Turnpike, warning motorists about the closure and urging them to follow designated detours or to get off on earlier exits.
Meanwhile, construction crews will take steps to minimize the noise disturbances in the Back Bay neighborhoods abutting the tunnel, Lambert said. He said project managers will try to avoid using jackhammers, and work requiring loud, ground-rattling noises will be scheduled for 9 p.m. rather than the wee hours.
Workers will erect temporary sound barriers to contain the din. And trucks will be outfitted with special reverse alarms that emit a loud, low-pitched “whoosh,” rather than a shrill beeping, so the sound will be less noticeable to residents blocks away.
The repairs, estimated to cost $3.1 million in state funds, are a stopgap measure for a deteriorating tunnel, which also received interim repairs four years ago.
State officials have held off doing a a complete overhaul of Storrow Drive because of a lack of funds.
The problem: Pavement on the westbound lanes of Storrow Drive, which run above ground, is too heavy, threatening to collapse the structure of the tunnel that houses the eastbound lanes.
“This will give us another 10 years or so in breathing room as we develop a longer-term strategy,” Lambert said.
If this interim project is not completed before the onslaught of wintry weather, then officials will suspend work and resume construction in April.
“We clearly could do this work much more quickly if we could just shut it down for a few weeks,” Lambert said. “But that was certainly not an option from our perspective.”
Most of the major structural work will occur on the westbound lanes, above ground. In an attempt to lighten the load on the tunnel’s roof beams, construction crews will shave off layers of pavement, night after night, sealing it over with a new thin finish of pavement that cumulatively will weigh less.
The construction project is also meant to improve storm drainage with new catch basins, a manhole, and a dry well. Additionally, crews will paint the tunnel walls and steel roof beams, and replace hundreds of feet of granite curb, along with metal guardrails.
“Unfortunately even this $3 million will not be a permanent fix in terms of the life of the tunnel,” Lambert said. “But it will certainly make sure that we don’t have any imminent danger or threat.”
The Department of Conservation and Recreation consulted with numerous organizations to allay their concerns about construction, including Harvard University and the Massachusetts Institute of Technology, Massachusetts General Hospital, Community Boating, and the Esplanade Association.
Although the project probably will not prevent people from getting access to the Esplanade — most people enter the park on foot or bicycles, and it is closed at night — Sylvia Salas of the Esplanade Association called for the state agency to do a better job of informing nearby of the problems that may arise because of the construction project.
“We have requested that the DCR increase communication with abutting neighborhoods regarding the project and any issues, such as traffic, noise, and park access,” Salas said.Martine Powers can be reached at email@example.com. Follow her on Twitter @martinepowers.