The Oroua River is a river of the southwestern

North Island The North Island, also officially named Te Ika-a-Māui, is one of the two main islands of New Zealand, separated from the larger but much less populous South Island by the Cook Strait. The island's area is , making it the world's 14th-largest ...

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

Name

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 arts, culture, built heritage, sport and recreation, and broadcasting sectors in New Zealand and advising government on ...

gives a translation of "place of dredging for shellfish" for .

Description

The Oroua River is a tributary of the Manawatu River, it flows generally southwestward from its source in the

Ruahine Range The Ruahine Range is the largest of several mountain ranges in the North Island of New Zealand that form a ridge running parallel with the east coast of the island between East Cape and Wellington. The ridge is at its most pronounced from the cen ...

. In its upper reaches, near the small town of

Āpiti Āpiti is a small township in the North Island of New Zealand. It is located to the northeast of the small town of Kimbolton, New Zealand, Kimbolton in the Manawatū-Whanganui region. It is located on a small plain, the Apiti Flats, close to the va ...

, the river passes through a deep gorge before emerging onto plains south of Kimbolton. Near

Feilding Feilding ( mi, Aorangi) is a town in the Manawatū District of the North Island of New Zealand. It is located on State Highway 54, 20 kilometres north of Palmerston North. The town is the seat of the Manawatū District Council. Feilding has w ...

, the Oroua River is fed by the Makino and Kiwitea streams, which are both significant tributaries. The river passes along the eastern edge of

, through Timona Park, where it is a popular local swimming spot. Beyond Feilding, the river feeds into the Manawatu River just to the west of

Opiki Opiki is a small rural settlement in the Horowhenua district of New Zealand's North Island. It is located on the floodplain of the Manawatu River, southwest of Palmerston North. Opiki and its surrounds had a population of 522 at the 2013 New Ze ...

(between

Palmerston North Palmerston North (; mi, Te Papa-i-Oea, known colloquially as Palmy) is a city in the North Island of New Zealand and the seat of the Manawatū-Whanganui region. Located in the eastern Manawatu Plains, the city is near the north bank of the ...

and Shannon).

Water Quality

Oroua River is in the bottom 25% of New Zealand's most polluted waterways. Some significant causes include run-off from local agriculture and issues relating to the Feilding Wastewater Treatment Plant. A 2011 report concluded that the quality fell from fair to poor at the AFFCO meat works effluent discharge point, but a 2015

resource consent A resource consent is the authorisation given to certain activities or uses of natural and physical resources required under the New Zealand Resource Management Act (the "RMA"). Some activities may either be specifically authorised by the RMA or ...

application claimed an 87% improvement in that effluent quality. In spite of this, Oroua was awarded the New Zealand River award from Land, Air, Water Aotearoa (LAWA) for significant improvements in dissolved reactive phosphorus, nitrogen,

e. coli ''Escherichia coli'' (),Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. also known as ''E. coli'' (), is a Gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus ''Escher ...

, and

turbidity Turbidity is the cloudiness or haziness of a fluid caused by large numbers of individual particles that are generally invisible to the naked eye, similar to smoke in air. The measurement of turbidity is a key test of water quality. Fluids can ...

Wildlife

Near the top of the Oroua River is one of the most significant

whio The blue duck or whio (''Hymenolaimus malacorhynchos'') is a member of the duck, goose and swan family Anatidae endemic to New Zealand. It is the only member of the genus ''Hymenolaimus''. Its exact taxonomic status is still unresolved, but i ...

populations. It is the southernmost wild population of the bird in the north island.

Flooding

The river, and surrounding areas, have been the site of many floods over the years. Major flooding has been recorded in the area in 1880, 1897, 1902, and 1953. In February 2004, significant rainfall in the surrounding streams caused a once-in-a-hundred-years flood. The flooding forced over 500 people from their homes and over $100 million in damage. The plains near Opiki have also faced flooding where the river meets the Manawatu River.

References

Rivers of Manawatū-Whanganui Rivers of New Zealand {{ManawatuWanganui-river-stub