Constable Sam Rundle said the woman, transported to Dunedin hospital by the Otago Regional Rescue Helicopter with ''reasonably serious injuries'', was expected to be released in the next day or two.
Two other people involved in the crash, which occurred just before 10am on Saturday, were released from Dunstan hospital in Clyde yesterday afternoon.
Alcohol was believed to be a factor in the accident, and police were awaiting results of an evidential blood test, Const Rundle said.
The vehicles involved in the accident at the Cromwell entrance to the Kawarau Gorge were both removed from the scene by a tow truck.
Const Rundle said one of the vehicles, a Mazda MX5 travelling towards Cromwell, was ''pretty destroyed''.
''There has been a lot of force involved,'' he said.
A male and female in the car were cut free by emergency services, he said.
Senior Sergeant Matt Scoles said another female, the sole occupant of the other vehicle travelling towards Queenstown, was taken to the Cromwell Medical Centre and then Dunstan Hospital to be treated for shock.
After the accident the road was closed at either end for periods as emergency services worked at the scene, before being cleared by roading contractors and opened about 11.15am.
Road conditions overnight in Central Otago had been reported as ''pretty good'', and it was not clear if driving conditions were a factor.
Const Rundle said both vehicles involved were registered to Cromwell owners.
