The Ōreti River (formerly the Oreti River) is one of the main rivers of

Southland, New Zealand Southland () is New Zealand's southernmost Regions of New Zealand, region. It consists of the southwestern portion of the South Island and includes Stewart Island. Southland is bordered by the culturally similar Otago, Otago Region to the north ...

, and is long. The river has been identified as an

Important Bird Area An Important Bird and Biodiversity Area (IBA) is an area identified using an internationally agreed set of criteria as being globally important for the conservation of bird populations. IBA was developed and sites are identified by BirdLife Int ...

BirdLife International BirdLife International is a global partnership of non-governmental organizations that strives to conserve birds and their habitats. BirdLife International's priorities include preventing extinction of bird species, identifying and safeguarding i ...

because, for much of its length, it supports breeding colonies of

black-billed gull The black-billed gull (''Chroicocephalus bulleri''), also called Buller's gull or ( Māori), is a Near Threatened species of gull in the family Laridae. This gull is found only in New Zealand, its ancestors having arrived from Australia arou ...

s. The New Zealand

Ministry for Culture and Heritage The Ministry for Culture and Heritage (MCH; ) is the department of the New Zealand Government responsible for supporting the Creative New Zealand, arts, Culture of New Zealand, culture, New Zealand Historic Places Trust, built heritage, Sport Ne ...

gives a translation of "place of the snare" for . In November 2019, the name of the river was officially altered to Ōreti River. The Ōreti has its headwaters close to the

Mavora Lakes Mavora Lakes is a protected area in the South Island The South Island ( , 'the waters of Pounamu, Greenstone') is the largest of the three major islands of New Zealand by surface area, the others being the smaller but more populous North ...

between Lake Te Anau and

Lake Wakatipu Lake Wakatipu () is an inland lake (finger lake) in the South Island of New Zealand. It is in the southwest corner of the Otago region, near its boundary with Southland, New Zealand, Southland. ''Lake Wakatipu'' comes from the original Māori l ...

, and flows south across the

Southland Plains The Southland Plains is a general name given to several areas of low-lying land in the South Island of New Zealand, separated by the rise of the Hokonui Hills in the north. It forms a sizeable area of Southland region and encompasses its two p ...

to its outflow into

Foveaux Strait Foveaux Strait ( ; ) is a strait that separates Stewart Island from the South Island of New Zealand. The width of the strait ranges from about , and the depth varies between . The strait was first charted by an American Seal hunting, sealer, O ...

at the southeastern end of Oreti Beach. En route, it runs through the towns of Lumsden and Winton, before passing through the city of

Invercargill Invercargill ( , ) is the southernmost and westernmost list of cities in New Zealand, city in New Zealand, and one of the Southernmost settlements, southernmost cities in the world. It is the commercial centre of the Southland Region, Southlan ...

, close to the river's

estuary An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime enviro ...

. For the final part of the river's length, around the city of Invercargill and the river's estuary just south of the city, it is locally known as the New River, a name occasionally encountered to refer to the whole river. It shares this estuary with several smaller rivers, most notably the Waihopai River. The New River Estuary, which meets the end of the Ōreti River before it reaches the sea, is in decline. Recent science reports show that regions of the upper estuary are under stress and showing eutrophication. There is excessive macroalgal growth including sediment quality decline and high concentrations of chlorophyll-a in the water column. Chlorophyll-a was used as an indicator of eutrophic conditions in the water column, and is a colour pigment present in many types of algae that can give an indication of how much algae is present in the water column. The Invercargill Rowing Club relocated to the river in 1958.

References

Rivers of the Southland Region Important Bird Areas of New Zealand Foveaux Strait Rivers of New Zealand {{Southland-river-stub