The Waioeka River is found in the north of New Zealand's North Island. It flows north for from Te Urewera National Park to reach the sea at Opotiki. It shares its estuary with the Otara River. History The area around the Waioeka valley was the scene of much fighting during the New Zealand wars. Rivers of the Bay of Plenty Region Rivers of the Gisborne District Rivers of New Zealand Ōpōtiki