Aropaoanui River

The Aropaoanui (Awapawanui) river runs through northern Hawke's Bay Region in the eastern North Island of New Zealand.

Etymology
Aropaoanui is a Māori word which roughly translates to 'big smoke'. In local myth, the area was named when the local tribe were roasting their captives on a fire after a victory in battle. The fatty pulp around the kidneys of their victims began to bubble, giving the impression that the victims were still alive, which terrified the tribespeople.

Geography
The upper part of the river, above its junction with the Mairau Stream, is called the Waikoau River, a name also given to a river in the South Island. The Waikoua rises from streams on the Maungaharuru Range, running generally south-southeastwards, flowing through steep-sided gullies. It is joined by a tributary, the Mahiaruhe Stream, which is the main outflow of Lake Tūtira, also known as Tūtira Stream where it leaves the lake, after which it continues south along the lake's western flank.

South of the lake, the river is crossed by State Highway 2 before veering eastward, joining with the Mairau Stream to become the Aropaoanui. It continues through a steep-sided valley past the Tangoio Forest, reaching its narrow floodplain just 3 km from the coast. Some small farms dot the upper part of the floodplain, accessed by a metal road which meets the Napier–Wairoa highway. The river empties into Hawke Bay, the waters joining the Pacific Ocean, just north of the small settlements of Tangoio and Waipātiki Beach, some 25 km north of Napier.

Ecology
The Aropaoanui has been described as one of the cleanest rivers in New Zealand by the Department of Conservation (only phosphorus levels are in the category of worst 25% of rivers and the river has longfin and shortfin eels, koura, inanga, torrent fish, blue gill bully, common bully, redfin bully, banded kōkopu and pātiki), and is fished for many species including trout and whitebait.

History
Floods in 1938 swept away the bridge on the Napier-Wairoa section of State Highway 2. The area around the river was also badly affected by floods in 2022.