Ahuriri Lagoon
Ahuriri Lagoon was a large tidal lagoon at Napier, on the east coast of New Zealand's North Island, that largely drained when the area was raised by the 1931 Hawke's Bay earthquake.
Before the earthquake, the lagoon stretched several kilometres from north to south, and covered roughly 4000 hectares, or 40 km2. The Tutaekuri River flowed into the southern end, and the Esk River into the northern end. Following the earthquake, the Esk was no longer able to flow into the lagoon and ran more directly to the sea. The Tūtaekurī still flowed into the lagoon after the earthquake but it caused flooding for the next few years, and by the end of the 1930s it had been diverted away from the lagoon to enter the sea at the mouth of the Ngaruroro River.
The land rise in the earthquake drained much of the lagoon, leaving a smaller estuary. Land reclamation and drainage work further reduced the estuary to its present size of 470 ha.
Cultural history
Māori named the lagoon Te Whanganui-a-Orotū after the chief Te Orotū. It was an important food source for Māori and supported a large population.European settlers established Napier on Scinde Island in the harbour, and it soon became a prosperous region on New Zealand's east coast. Napier's growth then halted, as there was not enough flat land to build on. The southern end of the lagoon stretched between Scinde Island and the mainland, separating Napier from the settlement of Taradale, and many people moving into the region chose Taradale over Napier because of the abundance of land. In the 1931 Hawke's Bay earthquake the lagoon was uplifted, exposing roughly 30 km2 of seabed. This included a new land bridge between Napier and Taradale. The towns grew over the years and Taradale amalgamated with Napier, forming Napier City, in 1968.