A tow truck hauled the car up the bank before it was covered by the tide.
Speed combined with a wet road surface were thought to have contributed to the crash, Walker said.
Just 15 minutes earlier, only 5km further along the road, another driver had crashed into a barrier at a popular spot known as Fishermans Pt at Waikaraka.
The driver was not with the vehicle, which had a damaged front bumper, when police arrived, because a member of the public had taken the driver to hospital. The car was towed and police were to speak with the driver later. Charges were still being considered for the crashes.