A changing climate is buckling concrete and flooding roads. States are moving slowly to guard the nation’s infrastructure.

Road flooding has become more common in the 45 years that Kathy Lock has owned a home in this beach community on the Delaware Bay. A marsh rises five or six times a year to swallow one of the two routes into town — the one used by school buses.

“These things are becoming increasingly more difficult to deal with,” said Lock, the town’s mayor. “Early on, we just didn’t have these same problems.”

As climate change causes seas to rise and storms to become more severe, the roads that connect Slaughter Beach and other hamlets up and down the coast to the rest of the state are flooding more often. The road repair bills are rising alongside the waters.