A B-double truck carrying pig compost has rolled on the Hexham-Woorndoo Road.
Terang police Sergeant Danny Brown said a 54-year-old Maryborough man lost control of the truck at Woorndoo about 8am on Thursday.
"The driver has come around a bend and the truck has rolled over onto its side, dumping compost onto the road," he said.
"I think it will be rather fertile on that side of the road."
Sergeant Brown said half the road was blocked and police were diverting traffic around the scene.
He said the driver was not injured and the truck would be towed.
He said speed could be a factor in the crash but investigations were ongoing.
Warrnambool Highway Patrol are also at the scene.
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