Accelerated Construction Cuts Comm Ave Bridge Work Time

Work materials lay near the Commonwealth Avenue bridge, whose eastbound lane is being replaced at an accelerated pace by the state. Photo by Jackie Ricciardi

Before Friday’s generally smooth rollout of work to replace the eastbound lane of the Commonwealth Avenue bridge, the Massachusetts transportation secretary tried to be upbeat about the impending traffic disruption.

“While it will be a hellish three weeks, if we weren’t using the accelerated bridge construction technique, it would be a hellish three or four or five years,” Stephanie Pollack said at news conference Tuesday by the half-century old bridge.

Pollack was referring to the state’s Accelerated Bridge Program, adopted in 2009 to expedite repairs on the state’s vital spans. Since 2008, Massachusetts has repaired 186 bridges under the program, with another dozen currently under construction.

The Comm Ave work, which last week shut down the bridge to motorists as well as to the MBTA Green Line B trolley between Blandford and Babcock Streets, will replace the eastbound lane, sidewalk, bike lane, and trolley area (the westbound side will be done next summer).

To make this a weeks-long rather than years-long experience, Pollack explained, requires two strategies: prefabricating the eastbound side of the bridge and working around the clock to install it.

At the news conference, she gestured in the direction of the Allston rail yard and said, “Basically, the new Commonwealth Avenue bridge is sitting there in pieces, almost assembled like a bridge…laid out exactly the way they’re going to be put in place” at the bridge site.

“For all intents and purposes, the inbound side of the Commonwealth Avenue bridge already exists,” she said. “It just exists as 267 prefabricated concrete deck panels and 44 girders that have been laid out in the configuration of the bridge at the rail yard.”

Flatbed trucks will ferry those pieces via the Massachusetts Turnpike, which runs under the bridge, to the construction site. There, with the aid of a giant crane, they will “be assembled by a team of up to 200 workers, working 24/7 over the next two weeks,” the secretary said. The goal is that on August 14, when Comm Ave is scheduled to reopen to traffic at 5 a.m., “everybody’s commuting on a new, inbound Commonwealth Avenue.”

Even with the fast-forward schedule, officials didn’t sugarcoat the hassles.

The bridge replacement is “one of the most disruptive projects that anyone can remember doing at the highway division in a very long time,” said Jonathan Gulliver, Massachusetts Department of Transportation (MassDOT) acting highway administrator, at the news conference.

With 30,000 motor vehicles traveling daily on Comm Ave, and with the bridge running over the Massachusetts Turnpike with its tens of thousands of drivers, this is “probably one of the most complicated intersections, interchanges, pieces of infrastructure anywhere in Massachusetts,” Pollack added. “The complexity of the project has required five years of planning to be able to pull it off and to fabricate all those concrete pieces.”

Dozens of states use similar rapid-construction techniques, and the US Department of Transportation has a geeky guide to the approach on its website.

The Comm Ave  bridge contractor wants to hasten the work as much as the public, as the state could impose up to $14.4 million in penalties if various milestones are missed during the work. “We do build incentives and disincentives into the contracts…to ensure that the contractor gets finished on time,” said Gulliver. “If it misses, there’s a heavy penalty. We want to do everything we can to get the project open and returned to service as quickly as possible.”

Pollack pledged that the state is working so that “decades from now, there is not some transportation secretary cursing the people from long ago for not doing maintenance and letting assets fall apart. A well-maintained asset like a bridge should last a century. This bridge did not. Hopefully, the next one will.”