BOSTON (CBS) – MassDOT says it’s replacing the 52-year-old Commonwealth Avenue Bridge at Boston University.

The agency says structural defects are the reason the bridge is getting replaced and the accelerated project is scheduled for completion by 2019.

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Highway Administrator Thomas Tinlin says the bridge is still safe.

“It does not mean unsafe. It means structurally deficient. It’s a 52-year-old structure and you start to see the corrosion on some of the support beams,” Tinlin said.

Artist’s drawing of the proposed Commonwealth Avenue bridge replacement project. (Graphic credit: MassDOT)

The project will get under way on July 26 and MassDOT says the work will affect traffic on the Mass Pike, Commonwealth Avenue at BU, the Green Line, the MBTA Commuter Line, and Amtrak service from Albany, NY to the South Station.

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(Image credit: MassDOT)

Goddard says shuttle service will be available at the BU stops for affected Green Line passengers. Bus service will also be available at the last two stops for affected passengers on the Worcester commuter rail line.

Goddard also says the project was “intentionally planned” for late July and August when the city has fewer major events. It’s after July 4 and before college students return from summer break.

WBZ NewsRadio 1030’s Ben Parker reports

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