The Waimakariri River is one of the largest rivers in Canterbury, on the eastern coast of New Zealand's South Island. It flows for 151 kilometres (94 mi) in a generally southeastward direction from the Southern Alps across the Canterbury Plains to the Pacific Ocean. Instead of being unoccupied Crown land as are most New Zealand river beds, the bed of the Waimakariri River is vested in the Canterbury Regional Council (Environment Canterbury).