Aging culverts across the United States are increasingly at risk of failure as they struggle to handle more intense and frequent storm events, raising concerns about infrastructure resilience and public safety. Culverts—underground tunnels or pipes that divert streams and storm runoff beneath roadways—often go unnoticed but play a critical role in preventing flooding and maintaining transportation access.
Jessica Boakye, an assistant professor of civil and environmental engineering at the University of Massachusetts at Amherst, led a detailed case study examining the consequences of culvert failures under severe storm conditions. Her research focused on the Deerfield River watershed in Franklin County, Western Massachusetts—a region with 783 culverts, 1,350 miles of road, and a single hospital serving its residents. By creating a geospatial model incorporating thousands of population nodes and road segments, Boakye’s team assessed the likelihood of individual culverts failing during extreme weather events.
The assessment relied on county data that documented each culvert’s condition to assign “risk of failure” scores. Such detailed knowledge is often lacking nationwide; a nonprofit research organization, Headwaters Economics, estimates that nearly two-thirds of the nation’s six million culverts are built to standards inadequate for today’s heavier storms. Franklin County’s infrastructure notably includes many culverts made from stacked stone or repurposed materials dating back more than a century, reflecting the area’s longstanding rural character.
The study’s simulations showed that even a single culvert failure could sever access for residents to emergency services. At moderate storm intensities, over 10 percent of the local population could be blocked from reaching the hospital, while in more severe scenarios, as many as 30 percent could be isolated due to widespread culvert failures. These findings come amid a pattern of culvert collapses elsewhere in the country, often linked to intense rainfall events. Recent failures in Georgia, Florida, Kentucky, and Washington State have stranded residents and delayed emergency response, underscoring the urgency of addressing aging drainage infrastructure.
Experts highlight that while bridges often receive more attention, culverts are integral to community connectivity. Robert G. Traver, a professor of civil and environmental engineering at Villanova University, emphasized that increasing rainfall intensity will likely cause more culvert failures in the future. Some officials, like Virginia’s state structure and bridge engineer Adam D. Matteo, expressed reservations about prioritizing culverts over bridges but acknowledged the importance of addressing culvert conditions as part of broader infrastructure planning.
Limited municipal funding complicates efforts to repair and replace deteriorating culverts, particularly when confronting the sheer number of structures in poor condition nationwide. Researchers at institutions including New York University and Vermont’s VT Culverts project are working to catalog and evaluate thousands of small culverts to help agencies prioritize interventions.
“The number of culverts is overwhelming, and proper upgrades are costly,” said Megan Rhodes, a regional planner involved in the Franklin County project. “Studies like this provide a roadmap to decide which culverts pose the greatest risk and need to be replaced first.”
As climate change drives more frequent and intense storm events, greater attention to the nation’s overlooked culvert infrastructure may be essential to avoiding disruptions to transportation, emergency services, and public safety.