The woman was the sole occupant of the vehicle, which had hit a bank, and she was treated by an off-duty paramedic for injuries to her sternum and right clavicle until St John Ambulance officers arrived.
Senior Constable Lox Kellas, of Portobello, said there appeared to be an oil slick of some sort on the road, and the Dunedin City Council had been called to clean it up.