New Sumner Tunnel project timeline is longer and more costly, but 'much more manageable'

A megaproject to repair the 88-year-old Sumner Tunnel under Boston Harbor will take place on a newly divided timeline, trading a later end date and higher costs for reduced disruption to motorists.

The state Department of Transportation announced Thursday that it will no longer close the key thoroughfare from May into early September. Instead, officials will replace the four-month continuous closure with a pair of shorter, roughly eight-week closures, one this summer and one next summer.

The tunnel running from East Boston to the downtown hub will now be shuttered to motorists from July 5 through Aug. 31, then again in July and August 2024, in a bid to concentrate the work during a time of year when traffic volumes are typically lowest.

"That gets us out of the school year, gets us out of the heaviest travel time period for business, and it really opens up a lot of possibilities with the community as far as reducing those impacts," Highway Administrator Jonathan Gulliver said in an interview. "It's still a very, very difficult project and still very difficult impacts, but much, much more manageable than what was originally proposed."

The plan highway officials detailed last year to address "disrepair" in the 88-year-old tunnel envisioned three phases: first, a series of 36 weekend-only closures, then a four-month shutdown from May to September 2023, and finally another batch of weekend closures in the fall and winter of 2023.

Now, Gulliver said, crews will keep doing some weekend work in the coming months, then the pair of roughly two-month summer shutdowns in 2023 and 2024, and a batch of additional weekend closures that will be more spaced out than originally planned.

The shift will push back the completion date from early 2024 into mid-2024, and it will also increase the cost beyond the roughly $160 million projected last year. Gulliver said he is not yet sure what the final price tag will be, citing ongoing negotiations, but argued that the added costs are worth the benefit for Bay Staters.

"Without putting an actual dollar figure on it, when we look at the impacts and look at the timeframes associated with it, the kind of money that we're talking about is the equivalent of us doing a pretty good incentive program," he said. "We're happy to pay those kinds of costs to reduce those impacts."

Gulliver praised the work of the design-build contractor, J.F. White, and the firm's familiarity with the tunnel as a key reason the shift became viable.

During the two-month shutdowns, crews will effectively be "taking down the ceiling and removing the floor, basically, of the tunnel at the same time," Gulliver said.

MassDOT also announced Thursday it will create a "project mitigation working group," bringing together municipalities, first responders, the MBTA, Massport, ride-hailing companies and other organizations affected by the tunnel work.

Gulliver said that panel will serve in an advisory role as the project unfolds, offering feedback and suggestions to problems that might arise along the way such as where to move affected bus stops.

"This is intended to be a catch-all, to really identify something that our project team may have missed and where we think we might have opportunities that we need to further explore," he said.


When it first opened to drivers in 1934, the Sumner Tunnel was the first of its kind in Massachusetts. And although it remains a major roadway today, particularly for those getting from Logan International Airport to downtown Boston and points west of the city, officials have warned its age is showing.

Drivers have already been grappling with some upheaval as a result of the project's first phase, which so far has involved 26 weekend-only closures of the tunnel. Those weekend shutdowns will continue until the second phase kicks off July 5, with occasional breaks for holidays and planned pauses.

The eastbound Callahan Tunnel, which runs parallel to the Sumner, is not closed as part of the project.

While the Sumner Tunnel is shuttered, motorists are directed to detours using the Ted Williams Tunnel — which travels both eastbound and westbound — and Route 1 across the Tobin Bridge, increasing traffic on those roadways.



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