The Ōhau River is a river in the

Mackenzie Basin The Mackenzie Basin (), popularly and traditionally known as the Mackenzie Country, is an elliptical intermontane river basin, basin located in the Mackenzie District, Mackenzie and Waitaki Districts, near the centre of the South Island of Ne ...

of New Zealand's South Island. It is the primary outflow of

Lake Ōhau Lake Ōhau is a lake in the Mackenzie Basin in the South Island of New Zealand. The Hopkins River, New Zealand, Hopkins and Dobson River, New Zealand, Dobson rivers fed into the northern end of Lake Ōhau. These rivers have their headwaters in ...

, from which it flows in a roughly eastward direction until reaching the artificial

Lake Benmore Lake Benmore is New Zealand's largest artificial lake. Located in the South Island of New Zealand and part of the Waitaki River, it was created in the 1960s by construction of Benmore Dam. Characteristics The lake has an area of about 75&nbs ...

after a distance of roughly . In 1981, the artificial

Lake Ruataniwha Lake Ruataniwha is an artificial lake in the Mackenzie Basin in the South Island of New Zealand. It was formed in 1977–1981 as part of the Waitaki hydroelectric project. It lies on the traditional boundary of the Canterbury and Otago provinces ...

was created along the river's length to power a small

hydroelectric Hydroelectricity, or hydroelectric power, is Electricity generation, electricity generated from hydropower (water power). Hydropower supplies 15% of the world's electricity, almost 4,210 TWh in 2023, which is more than all other Renewable energ ...

power station as part of the Waitaki hydro scheme. Prior to the creation of the Waitaki hydro scheme, the river flowed directly into the

Waitaki River The Waitaki River is a large braided river in the South Island of New Zealand. It drains the Mackenzie Basin and runs south-east to enter the Pacific Ocean between Timaru and Oamaru on the east coast. It starts at the confluence of the Ōhau Ri ...

rather than through a series of lakes. The river forms part of the traditional boundary between

Otago Otago (, ; ) is a regions of New Zealand, region of New Zealand located in the southern half of the South Island and administered by the Otago Regional Council. It has an area of approximately , making it the country's second largest local go ...

and

Canterbury Canterbury (, ) is a City status in the United Kingdom, city and UNESCO World Heritage Site, in the county of Kent, England; it was a county borough until 1974. It lies on the River Stour, Kent, River Stour. The city has a mild oceanic climat ...

regions. Prior to European settlement of the region, the river was a traditional '' mahinga kai'' (food gathering site) for

Māori Māori or Maori can refer to: Relating to the Māori people * Māori people of New Zealand, or members of that group * Māori language, the language of the Māori people of New Zealand * Māori culture * Cook Islanders, the Māori people of the Co ...

travelling through the Mackenzie Basin, providing valuable food sources such as

weka The weka, also known as the Māori hen or woodhen (''Gallirallus australis'') is a flightless bird species of the rail family. It is endemic to New Zealand. Some authorities consider it as the only extant member of the genus '' Gallirallus''. ...

tuna A tuna (: tunas or tuna) is a saltwater fish that belongs to the tribe Thunnini, a subgrouping of the Scombridae ( mackerel) family. The Thunnini comprise 15 species across five genera, the sizes of which vary greatly, ranging from the bul ...

(eels), and pora (''Brassica rapa subsp. sylvestris'').

References

Rivers of the Canterbury Region Rivers of Otago Rivers of New Zealand {{CanterburyNZ-river-stub