Aging infrastructure in Massachusetts has faced the relentless forces of time and nature, with crumbling concrete, exposed rebar, and rusted steel visible on bridges across the state. What lies beneath the surface is equally crucial in determining the safety of nearly 8,000 bridges that residents rely on daily.
Bill Colleran, an Underwater Operations Engineer with the MassDOT Bridge Inspection Dive Team, emphasized the importance of these underwater inspections to NBC10 Boston.
"There's a lot of eyes on the above-water stuff. So the underwater stuff nobody's really looking at except us," Colleran said.
Each day Colleran and his team dive into Massachusetts waterways to inspect nearly 1,250 bridges in Massachusetts that sit in 3 feet of water or deeper. Their work involves the meticulous examination of structural elements to assess the integrity of bridge components, looking for cracks, rust, and signs of erosion. When necessary they are equipped to make repairs on the spot.
During a recent inspection of a bridge over the Powwow River in Amesbury, Colleran's team conducted a thorough evaluation.
"This bridge would be given a rating of seven, which is considered good."
The Federal Highway Administration rates bridge safety on a scale from zero to nine, with nine being excellent. Structurally deficient bridges typically score four or lower in one of three critical areas: the deck, superstructure, and substructure—which is what the dive team focuses on. Data obtained two years ago by NBC10 Boston showed that over 400 bridges in Massachusetts were structurally deficient. Today that number has risen to nearly 700.
MassDOT Chief Engineer and Deputy Administrator Carrie Lavallee acknowledged to NBC10 Boston that the state’s infrastructure is aging but explained that structurally deficient does not mean unsafe.
"We make sure that no matter what the condition of the bridge is, it's always safe," Lavallee said. She stressed that the agency is constantly monitoring and inspecting bridges to ensure safety.
In addition to scheduled inspections, dive teams occasionally conduct emergency inspections in situations such as the major flooding emergency in Leominster last year. Lavallee highlighted that their work is critical in developing the agency’s resiliency plan and directing millions of dollars in funding to where it’s needed most.
Despite the increasing number of structurally deficient bridges, Colleran said he sees progress.
"Bridges that are in worse shape and getting repairs are getting replaced, and the state's really prioritizing the ones that are in the worse shape," he said.
Colleran said his dive team plays a pivotal role in safeguarding Massachusetts' bridges, ensuring they remain safe and functional for years to come.