Dwane Vandelicht of the state’s transportation department says lots of rain and then extreme heat can cause concrete roads to blow up. He says when water gets trapped in and under concrete, which then gets hot, it expands, and has nowhere else to go.
He says there’s no way to know where or when it will happen, but the road can blow up to 12 inches on one side, and that can hurt a car. Other times smaller pieces of concrete will crumble off the road.
Older concrete roads with lots of cracks are more likely to be affected, and he says roads with asphalt are often safer. The asphalt acts as a seal to keep water out and an insulator to keep the concrete cooler.
He says if a driver sees this happen, to slow down as much as possible and then call the transportation department.