The heat and humidity of late has caused problems along a concrete stretch of Highway 402 in Lambton County.
There were alternating lane closures Thursday in the westbound lanes near Oil Heritage Road.
Maintenance crews had to repair a section of the road surface that had buckled.
Ministry of Transportation West Region Communications Coordinator, Liane Fisher Bloxam, said concrete pavements are constructed with joints filled with a rubberized sealant to allow the concrete to expand.
"Occasionally, under extreme high temperatures and humidity, the expansion force may cause the concrete to buckle," Fisher Bloxam said in an email to BlackburnNews.com. "Buckling may also be exacerbated by sand or debris in the joint. MTO works with its contractors to monitor and repair the joints or the pavement as quickly as possible."
Fisher Bloxam said crews made a temporary repair Wednesday night, and replaced that work with a medium term repair Thursday until a final repair can be made in August.
All lanes were expected to be open again around 9 a.m. Friday.
