Projected Rise in N.H. Groundwater Levels Could Harm New Hampshire's Roads

May 31, 2017

By the end of this century, scientists predict the ocean on New Hampshire’s coast will rise anywhere between 4 and 6.5 feet above where it is today—a consequence of climate change. But when the sea rises, groundwater rises to keep up. That would spell trouble for roadways, even roads inland from the ocean, according to a new study from UNH.

Jo Daniel, a professor of Civil and Environmental Engineering at UNH, explains that “materials underneath the pavement structure that are providing the support, when they’re wet, they’re not as strong. So essentially, you’re going to see the roads deteriorating faster.”

Smaller roads are at higher risk, such as Route 286 in Seabrook and Gosling Road in Portsmouth. In the future, towns may have to redesign roads using stronger materials, or repair them more often.