Police were advised of the crash south of Weld Pass at 7.15am on Thursday. Photo: Rafael Ben-Ari/Chameleons Eye/123RF
State Highway 1 near Seddon is blocked after a truck and trailer rolled on Thursday morning.
It is understood to have been carrying grapes, as harvest is underway in the Marlborough region.
Police were advised of the crash south of Weld Pass at 7.15am.
Hato Hone St John sent an ambulance to the scene, and the crew treated and transported one person in a minor condition to Wairau Hospital.
Waka Kotahi said the highway was expected to be closed for several hours while the crash scene was cleared, and no detour was available.
If travelling between Christchurch and Blenheim, drivers should delay their travel or use the inland route via Lewis Pass.