Any baker knows that yeast and heat will make dough rise.
It just usually doesn’t happen along 30 miles of Interstate 5.
Bags of dough in an open container truck began to split and spill their contents over the truck’s sides Monday afternoon.
“It must be because of the heat and the yeast,” said Washington State Patrol spokeswoman Brooke Bova.
Callers to 911 first reported a “foam-like” substance spilling from the truck in Olympia, she said.
The driver eventually pulled over around South 56th Street in Tacoma.
By that time, black bags of dough were swelling, splitting open and spilling onto the shoulder.
The driver picked up the load at the state Route 12 exit near the Thurston and Lewis county line, Bova said.
He was on his way to a plant on Portland Avenue in Tacoma that processes food waste into animal feed.
A crew from the plant was headed to the scene at about 4 p.m. to clean up the mess but were delayed by heavy traffic, Bova said.
The driver was stuck in traffic as well, which could explain the unplanned rising.
Meanwhile, the doughy mass was expanding onto I-5, she said.
“There’s a bag now that looks like it’s about to burst,” she said.