A truck loaded with 3,700 pounds of hydrochloric acid tipped over along the east shore of Flathead Lake on Thursday — but none of the toxic cargo spilled.

However, the painstaking work of clearing the accident scene slowed and at times blocked traffic on Montana 35 all day on Thursday.

The semi truck rolled on its side Thursday morning 5 miles south of Yellow Bay, blocking one lane of Montana 35. 

None of the acid spilled onto the roadway that hugs Flathead Lake.

Trooper Terrance Rosenbaum with the Montana Highway Patrol said that the driver was “sightseeing” and veered his truck, which pulled a trailer and an additional “pup” trailer. 

“The next thing he knew, the vehicle went to the right, toward the hillside, and ended up flipping a tractor and the first trailer,” Rosenbaum said.

The Montana Department of Transportation and local agencies worked to clear the blockage through Thursday afternoon. 

Rosenbaum said that a crew was called in to transfer the liquid acid into another container. A bit of oil was spilled from the truck.

At around 1 p.m., the highway was completely blocked so tow crews could work to right the truck. One lane reopened nearly two hours later.