Replacing Bourne and Sagamore bridges is overdue, but hundreds of Mass. bridges are ‘structurally deficient’

The Sagamore Bridge.David L. Ryan/Globe staff/file

Federal funding that would have gone toward the replacement of the aging Bourne and Sagamore bridges was once again denied last week.

The two Cape bridges, which serve tens of thousands of vehicles daily, are long overdue for replacement, having been deemed “functionally obsolete” in 2019 by the federal government, which built the landmark spans and is responsible for their maintenance. Completed in 1935, the bridges were intended to last about 50 years.

Though the battle to replace the Bourne and Sagamore bridges often draws headlines and attention, there are hundreds of bridges across the Commonwealth in need of repair, according to federal data. More than 400 Massachusetts bridges, or about 8 percent, were rated “poor” after their last inspection, according to the Federal Highway Administration, which maintains a national inventory of bridges and their inspection reports.

The Bourne Bridge. John Tlumacki/Globe Staff/file

One bridge between Dennis and Yarmouth that carries traffic from Route 28 over the Bass River fared especially poorly in a 2021 inspection report, with the substructure, superstructure, and deck all listed as being in “serious” condition. That bridge is slated for replacement next year, and in the meantime, officials have installed barriers preventing drivers from accessing outer portion of the bridge “where substructure issues have been noted,” a MassDOT spokeswoman told the Globe.

A bridge in Fitchburg (also slated for replacement) that carries Water Street traffic over Boulder Drive and railroad tracks received an alarming inspection report in 2021, with the superstructure rated “critical.” MassDOT has not yet provided requested information about the current status of that bridge.

According to the most recent federal data, the Bourne bridge is currently among those designated “structurally deficient” due to the condition of the bridge superstructure, though the Sagamore is rated in “fair” condition.

The Federal Highway Administration uses a rating system to assess various bridge components, and a bridge is deemed “structurally deficient” if any one of the components earns a rating of “poor” or lower. In the case of the Bourne bridge, the superstructure earned a rating of “poor,” while the other components all rated “fair” or better. It’s important to note a designation of “structurally deficient” does not necessarily mean the bridge is unsafe.

The federal data is not without flaws. Experts told the Globe that while the database is the most comprehensive accounting of the safety and maintenance of the nation’s bridges available, location errors permeate the data. In addition, an archaic cataloguing system leaves out common names, making it difficult for commuters to easily look up the condition of their local bridges by either name or location. Finally, updated data is released annually, rather than on a rolling basis, so the condition of a bridge may have improved (or gotten worse) since the last update.

Below is the most recent map of structurally deficient bridges in Massachusetts. The data was last updated in early 2022.