The 87-year-old man was coming out of his driveway in his Mazda Familia sedan just after 1pm yesterday, and police believed he failed to see a Kenworth logging truck, owned by Philip Wareing Ltd, travelling south, Sergeant Wayne Brew, of Oamaru, said.
The unladen logging truck, with its trailer on the rear deck, hit the front of the car on the driver's side, and both vehicles travelled about 35m before they stopped on opposite sides of the road.
The car was pushed into about a metre-high bank, the front partly blocking the southbound lane.
The truck stopped on the opposite side of the road on top of a bank with its nose in a tree.
Police, ambulance and the Oamaru fire crash unit, along with a commercial vehicle investigation unit, attended the crash.
The police serious crash unit attended later.
The man was trapped in his vehicle for more than an hour.
Rescuers had to cut the roof off and lever the crushed driver's side door open before he could be removed from the car.
He was taken by ambulance to a paddock beside the historic Clark's Mill, just south of the crash, where he was picked up by the Otago Regional Rescue Helicopter and transferred to Dunedin Hospital.
The truck driver received a minor back injury.
A detour away from SH1 around the crash site was in place for about seven hours.
Initially, vehicles were diverted about 18km to Gemmels Crossing across the Kakanui River via Kakanui Valley and Woolsheds Rds.
However, the detour was shifted closer to the crash using Round Hill Rd, a diversion of about 16.5km, after some drivers lost their way and were driving through the crash site.
Later, heavy vehicles were allowed through the crash site on one lane.
