Senior Sergeant Craig Brown of the Police Southern District Communications Centre said the driver managed to get out of the cab and received only ''superficial injuries''.
The Otago Daily Times understands the man initially struggled to get out because the cab was partially submerged in water contained in the ditch.
The truck left the road on a 65kmh corner 4km south of Lawrence. Empty pallets and bottles it was carrying were strewn across a farm paddock and a neighbouring road.
The road was reduced to one lane when the crash happened about 9.15am and again about 2.30pm.
A Mainfreight Auckland headquarters spokesman confirmed the truck was dispatched from the Cromwell branch and was heading south at the time.
Senior Constable Robert Wallace, of Lawrence, said the Commercial Vehicle Investigation Unit attended the scene and inquiries were continuing into the crash.
Mainfreight Cromwell would not comment on the accident.