Here’s how many bridges in Mass. are ‘structurally deficient’

The average Massachusetts resident lives 1.7 miles from a structurally deficient bridge.

A new report released Tuesday from a Massachusetts think tank calls for investment into the state’s bridges, after its analysis found that one in 12, or 8%, are “structurally deficient.”

The Massachusetts Budget and Policy Center (MassBudget) looked at the Department of Transportation’s data on the status of bridges, and found that out of the state’s 7,880 bridges, 644 are considered structurally deficient.

A structurally deficient bridge is not at immediate risk of collapsing. It is defined by the state as having at least one major weight-bearing component that has serious problems and is in need of repair or replacement.

“Every bridge in our Commonwealth should be safe, well maintained, and open for travel,” MassBudget wrote in its report. “…Bridges link goods to markets, workers to jobs, and families to essential services.”

MassDOT collects data on the status of bridges in the state and has created a map of structurally deficient bridges. – MassDOT

How big is the problem?

According to the think tank’s analysis, structurally deficient bridges tend to be larger and carry more traffic. On average, 11% of daily bridge crossings are over structurally deficient bridges, MassBudget wrote. This amounts to 14.3 million crossings a day.


This problem is not as severe in other states. According to the report, in 2020, MassDOT found that Massachusetts had the fourth highest percentage of bridges that were deemed in “poor condition” out of the 50 states.

Additionally, the report cited a 2021 study of National Highway System (NHS) bridges which found that only a quarter of Massachusetts NHS bridges were graded in “good condition,” compared with 45% nationally. 

But the problem has an outsized impact on some communities, the report found.

While the average Massachusetts resident lives 1.7 miles from a structurally deficient bridge, people belonging to a racial or ethnic minority live an average of 1.3 miles from a structurally deficient bridge, and a limited English-speaking household lives 1.2 miles from such bridges, on average.

How does the problem impact us?

While a bridge collapse is extremely rare, the report said, structurally deficient bridges cause other problems, such as bridge closures or weight restrictions.

“When heavy trucks can’t pass on the most direct route over a river, for instance, they must drive a longer, less direct route,” MassBudget wrote.

“As a result, commerce is slowed, time is wasted in traffic congestion, additional fuel is burned, and trucks sometimes end up driving through residential areas they would otherwise avoid.”


The report said that weight-limited bridges can also delay the response time of rescue vehicles such as fire trucks, which is a particular problem in rural communities.

One in 13 bridges in Massachusetts have weight limits, according to the report.

How did the problem get so bad?

There are a few reasons Massachusetts bridges are in such disrepair, according to the report. Firstly, it said our harsh winters cause roadways to contract and suffer from salt exposure, accelerating deterioration of the bridges.

Secondly, Massachusetts bridges are typically older than bridges in other states. On average, the report said, a Massachusetts bridge was built or most recently reconstructed 56 years ago, while the average bridge age nationally is 44 years old.

But deterioration will accelerate if nothing is done. Not only will climate change lead to more flooding, erosion, and precipitation, according to the report, but it will lead to more extreme weather that our bridges are not built to withstand.

Additionally, trucks and emergency vehicles have gotten heavier over time. Electric cars, which are on the rise, are also heavier than gas-powered cars.

Our bridges were built to withstand vehicle weight loads that were the norm 50+ years ago, not the new, heavier vehicles we see today, the report said.

How do we fix the problem?

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The solution to this problem is a “significant” investment by the state into efforts to repair and replace bridges, according to the report.


While the report did not specify how much money would be needed to fix the 644 structurally deficient bridges, it said that the longer the state waits to the fix the problem, the more costly it will be, as the bridges will continue to degrade.

The last time the state invested in bridges was in 2008 when it put $3 billion into the Accelerated Bridge Program, which rehabilitated or replaced nearly 300 bridges.

The report recommends the state institute a similar investment into our bridges.

“The integrity of our bridges for the decades ahead depends greatly on the decisions we make in the next few years,” MassBudget wrote. “The problem of structurally deficient bridges is serious and widespread, but it is a problem we can choose to fix.”


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