The Rakaia River is in the

Canterbury Plains The Canterbury Plains () are an area in New Zealand centred in the Mid Canterbury, to the south of the city of Christchurch in the Canterbury region. Their northern extremes are at the foot of the Hundalee Hills in the Hurunui District, and ...

New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...

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 Island and Stewart Island. It is bordered to the north by ...

. The Rakaia River is one of the largest

braided river A braided river (also called braided channel or braided stream) consists of a network of river channel (geography), channels separated by small, often temporary, islands called ''braid bars'' or, in British English usage, ''aits'' or ''eyots''. ...

s in New Zealand. The Rakaia River has a mean flow of and a mean annual seven-day low flow of . In the 1850s, European settlers named it the ''Cholmondeley River'', but this name lapsed into disuse. The name ''Rakaia'' comes from

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 ...

"Ō Rakaia", meaning the place where people were arranged by ranks.

Description

It rises in the

Southern Alps The Southern Alps (; officially Southern Alps / Kā Tiritiri o te Moana) are a mountain range extending along much of the length of New Zealand, New Zealand's South Island, reaching its greatest elevations near the range's western side. The n ...

, travelling in a generally easterly or southeasterly direction before entering the

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five Borders of the oceans, oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is ...

south of

Christchurch Christchurch (; ) is the largest city in the South Island and the List of cities in New Zealand, second-largest city by urban area population in New Zealand. Christchurch has an urban population of , and a metropolitan population of over hal ...

. It forms a

lagoon A lagoon is a shallow body of water separated from a larger body of water by a narrow landform, such as reefs, barrier islands, barrier peninsulas, or isthmuses. Lagoons are commonly divided into ''coastal lagoons'' (or ''barrier lagoons'') an ...

as it reaches the ocean. For much of its journey, the river is braided, running through a wide shingle bed. Close to

Mount Hutt Mount Hutt () rises to the west of the Canterbury Plains in the South Island of New Zealand, above the braided upper reaches of the Rakaia River, and 80 kilometres west of Christchurch. Its summit is 2190 metres above sea level. The New Zeala ...

, however, it is briefly confined to a narrow canyon known as the

Rakaia Gorge The Rakaia Gorge is located on the Rakaia River in inland Canterbury in New Zealand's South Island. Like its neighbour, the Waimakariri River, the Rakaia runs through wide shingle beds for much of its length, but is forced through a narrow c ...

. The Rakaia River is bridged in two places. The busiest crossing is at the small town of

Rakaia Rakaia is a town sited on the southern banks of the Rakaia River on the Canterbury Plains in New Zealand's South Island, approximately 57 km south of Christchurch on State Highway 1 and the Main South Line. Immediately north of the townsh ...

, from the river mouth, where

State Highway 1 The following highways are numbered 1. For roads numbered A1, see list of A1 roads. For roads numbered B1, see list of B1 roads. For roads numbered M1, see List of M1 roads. For roads numbered N1, see list of N1 roads. For roads numbered S ...

using

Rakaia Bridge The Rakaia Bridge is New Zealand's longest road bridge and crosses the Rakaia River, one of Canterbury, New Zealand, Canterbury's large braided rivers. The present bridge was opened in 1939 and replaced an earlier combined road and rail bridge f ...

and the

South Island Main Trunk Railway The Main North Line between Picton and Christchurch and the Main South Line between Lyttelton and Invercargill, running down the east coast of the South Island of New Zealand, are sometimes together referred to collectively as the South Isl ...

cross the river using separate bridges. These two bridges are New Zealand's longest road and rail bridges respectively, approximately long. A second bridge, much shorter and less used, spans the Rakaia Gorge. The Central Plains Water Trust is proposing to take up to of water from the Rakaia River as part of the Central Plains Water enhancement scheme. The Rakaia River is a celebrated

Chinook salmon The Chinook salmon (''Oncorhynchus tshawytscha'') is the largest and most valuable species of Oncorhynchus, Pacific salmon. Its common name is derived from the Chinookan peoples. Other vernacular names for the species include king salmon, quinn ...

fishery. It 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 it supports breeding colonies of the

endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching, inv ...

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 ...

. The river is also known for its large

wrybill The wrybill or (in Māori language, Māori) ngutuparore (''Anarhynchus frontalis'') is a species of plover Endemic (ecology), endemic to New Zealand. It is the only species of bird in the world with a beak that is bent sideways in one direction, ...

population which represents 73 percent of the total population. Other important bird species using the riverbed are

black-fronted tern The black-fronted tern (''Chlidonias albostriatus''), sea martin, ploughboy, or tarapiroe Māori language, (Māori), is a medium-small tern endemic to New Zealand. Black-fronted terns can be found in coastal habitats from the southern tip of th ...

and

banded dotterel The double-banded plover (''Anarhynchus bicinctus''), known as the banded dotterel or pohowera in New Zealand, is a species of bird in the plover family. Two subspecies are recognised: the nominate ''Charadrius bicinctus bicinctus'', which bree ...

.O’Donnell, C.F.J. (2000). The significance of river and open water habitats for indigenous birds in Canterbury, New Zealand, Environment Canterbury Unpublished Report U00/37.

References

External links

Selwyn District Council page for the Rakaia RiverTe Ara website page for the Rakaia RiverSalmon fishing on the Rakaia River
{{Rakaia Rivers of the Canterbury Region Braided rivers in New Zealand Important Bird Areas of New Zealand Rivers of New Zealand