The Mangaone River is a river of the
Hawke's Bay region
Hawke's Bay ( mi, Te Matau-a-Māui) is a local government region on the east coast of New Zealand's North Island. The region's name derives from Hawke Bay, which was named by Captain James Cook in honour of Admiral Edward Hawke. The region is ...
of
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 ...
's
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 ...
. Its source is numerous streams draining the slopes of the Te Waka Range in the
Rukumoana Forest area. The river flows southeast then south through rugged hill country until it meets the
Tutaekuri River. For most of its course it is deeply
incised
Incision may refer to:
* Cutting, the separation of an object, into two or more portions, through the application of an acutely directed force
* A type of open wound caused by a clean, sharp-edged object such as a knife, razor, or glass splinter
...
in the
tephra
Tephra is fragmental material produced by a volcanic eruption regardless of composition, fragment size, or emplacement mechanism.
Volcanologists also refer to airborne fragments as pyroclasts. Once clasts have fallen to the ground, they rem ...
,
ignimbrite
Ignimbrite is a type of volcanic rock, consisting of hardened tuff. Ignimbrites form from the deposits of pyroclastic flows, which are a hot suspension of particles and gases flowing rapidly from a volcano, driven by being denser than the surrou ...
and
lapilli
Lapilli is a size classification of tephra, which is material that falls out of the air during a volcanic eruption or during some meteorite impacts. ''Lapilli'' (singular: ''lapillus'') is Latin for "little stones".
By definition lapilli range f ...
volcanic rocks, which are a bit over 30,000 years old. The deep valleys are partly due to the soft rocks and partly to the rapid rise of the
Mohaka Fault, at over a year.
Totara
''Podocarpus totara'' (; from the Maori-language ; the spelling "totara" is also common in English) is a species of podocarp tree endemic to New Zealand. It grows throughout the North Island and northeastern South Island in lowland, montane and ...
was being felled along the river in the 1860s. The river suffers from pollution by nitrogen and phosphorus.
After
Cyclone Gabrielle
Severe Tropical Cyclone Gabrielle was a severe tropical cyclone that devastated the North Island of New Zealand and affected parts of Vanuatu and Australia in February 2023. It is the costliest tropical cyclone on record in the Southern Hemisphe ...
in February 2023,
Rissington bridge was replaced by a long
Bailey bridge
A Bailey bridge is a type of portable, pre-fabricated, truss bridge. It was developed in 1940–1941 by the British for military use during the Second World War and saw extensive use by British, Canadian and American military engineering units. A ...
on 31 March 2023 and
Dartmoor
Dartmoor is an upland area in southern Devon, England. The moorland and surrounding land has been protected by National Park status since 1951. Dartmoor National Park covers .
The granite which forms the uplands dates from the Carboniferous ...
bridge on 5 April 2023. They are the only bridges over the river.
See also
*
List of rivers of New Zealand
This is a list of all waterways named as rivers in New Zealand.
A
* Aan River
* Acheron River (Canterbury)
* Acheron River (Marlborough)
* Ada River
* Adams River
* Ahaura River
* Ahuriri River
* Ahuroa River
* Akatarawa River
* Ākiti ...
References
Rivers of the Hawke's Bay Region
Rivers of New Zealand
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