ST. LOUIS — The searing heat of the last 10 days, preceded by a long wet spring, has caused road pavement around Missouri to buckle or blow up.
A highway expert in St. Louis said the phenomenon is not just a problem in Missouri, but around the country.
When pavement temperatures rise, concrete slabs expand, push up against each other and either heave up or crumble.
Owen Hasson, maintenance superintendent for the St. Louis County District of the Missouri Department of Transportation, said wet conditions like those that preceded the heat exacerbate the problem.
Hasson said the only thing the transportation department can do is temporarily fix the blown-up sections of road and schedule them for permanent repair.
Temperatures around the state have been in the 90s for 10 days, giving Missourians an early burst of summer.
The intense heat and sunshine, following up on extremely wet spring conditions, have made the buckling and blowups happen a little earlier than usual.
"The long session of 90-plus degree temperatures along with the rain were the perfect condition to brew up a blowup," Hasson said. "You cannot predict where it's going to happen; we just get out there as soon as we can."
Hasson said it doesn't make sense to postpone repairs until temperatures cool because cool conditions aren't good for pouring concrete.
Missouri doesn't track the number of blowups around the state. But the Transportation Department's Jim Carney, the state maintenance engineer, said Missouri spent $7.6 million last year on concrete replacement projects, including blowups.
In southeast Missouri's Stoddard County, the Transportation Department reported 26 incidents in three days this week.
Anyone who encounters the problem is asked to report it online at modot.gov or by calling 1-888-ASK-MODOT.