State Highway 7 in North Canterbury has re-opened after a crashed truck and trailer unit was cleared from the road near the Hanmer turnoff.
Police were called to the scene about 5pm on Tuesday and say the truck and trailer unit jack-knifed before crashing and spilling timber on the road.
The truck driver suffered serious injuries and has been flown to Christchurch Hospital.
Motorists had been warned to expect long delays as the truck and its contents blocked the highway and there was no possible detour.
Specialist machines were needed to clear the road, which reopened at 9.30pm.