All lanes of southbound Interstate 5 were closed at Milepost 78 for seven hours Thursday after a crash involving a semitrailer at West Street in Chehalis.
The crash was reported about 6:40 a.m., and crews spent several hours working to clear debris and hazardous materials from the roadway.
The Washington State Department of Transportation reported at 1:30 p.m. that all southbound I-5 lanes had reopened, but there was a 7-mile backup.
During the lane closure, southbound I-5 traffic was detoured onto Chamber Way to Louisiana Avenue to state Route 6, then returning to I-5.
The semitrailer, which was hauling car batteries, struck the West Street overpass and spilled a “substantial amount of diesel fuel” and sulfuric acid, WSDOT spokesperson Tamara Greenwell said.
Officials from the state’s bridge preservation office were inspecting the structural integrity of the overpass, and the Department of Ecology was cleaning up the fuel and sulfuric acid. Crews must also replace about 40 feet of the median barrier that was damaged in the crash.
The driver of the truck was airlifted to Harboview Medical Center with non-life-threatening injuries, Washington State Patrol Trooper Will Finn said. Witnesses told troopers that the truck was northbound when it crossed the concrete barrier into southbound lanes.
Two other vehicles were damaged by debris from the crash, but no injuries were reported, Finn said.
“When you look at the dynamics of the crash, we’re lucky there were no head-on collisions,” he said.
Tammy McGee: 360-754-5447