Treacherous conditions saw accident and emergency services called out to three vehicle crashes within two hours and created traffic jams for motorists travelling to the region's skifields.
Constable Mike Thomas, of Wanaka, said the "extreme" black ice was among the worst winter driving conditions he had seen on Upper Clutha roads.
He attended three single-vehicle crashes before 9am and had received reports of "numerous" other vehicles sliding off the icy roads.
The region's three fire rescue brigades, based at Wanaka, Lake Hawea, and Luggate were called to the different crashes, Const Thomas said.
A 4WD, carrying a 45-year-old Wellington driver and his 14-year-old daughter, rolled after hitting ice at Cardrona Valley Rd accident spot "the larches" about 7am.
The uninjured pair were taken by ambulance for a check at a medical centre, Const Thomas said.
Emergency services took about an hour to clear the accident site, which snarled traffic to Cardrona.
Traffic delays were compounded at the entrance to the skifield access road, as vehicles required chains to travel up the mountain. Queues stretched more than 2km towards Wanaka.
Another 4WD, driven by a 38-year-old Lake Hawea woman, also rolled after hitting ice, Const Thomas said.
The accident happened on the Maungawera Hill as the vehicle was travelling towards Wanaka. The woman was not seriously injured.
A car went off the road and hit a bank on State Highway 8A's shortcut road to the Luggate Red Bridge, Const Thomas said.
He reminded motorists to keep their speed down and drive to the winter conditions.
