Waihao River
Encyclopedia
The Waihao River is a natural watercourse
in the Canterbury
region of New Zealand
's South Island
.
, foothills of the Southern Alps
, and its catchment
area is 550 km². The catchment receives approximately 1,000 mm of rain annually. In its upper reaches, the river has two branches, the North Branch and South Branch, which join together at Waihao Forks. The river is well defined, but when it nears the coast, it becomes a braided river
and has a floodplain
of 25 km². When it reaches the coast, the river turns and flows northwards, being joined by the Waimate Creek
before discharging into the Wainono Lagoon
in Studholme
, a locality to the east of the town of Waimate
. However, a culvert known as the Waihao Box has been cut into the gravel berm
that separates the river from the Pacific Ocean
to provide permanent sea access.
crosses it near the coast between Willowbridge and Morven, while State Highway 82
crosses it inland at Waihao Forks. Near the State Highway 1 crossing, it is also crossed by the Main South Line
railway, and inland, it was formerly crossed by the Waimate Gorge Branch
. This branch line
closed in 1953 and the bridges have been removed.
. It is also followed by a walkway for approximately 5 km near Waihao Forks.
to lower erosion, and restricting development to mitigate damage.
In 2000, two special needs students aged 13 and 15 drowned while on a school trip to Black Hole, a swimming hole on the Waihao River. This event stimulated a re-assessment of school policies, and partly as a response to the incident, new safety guidelines were issued by the Ministry of Education
. In 2004, the mothers of the students sued the high school for breaching its duty of care to the students; the case was settled out of court in September 2007.
Stream
A stream is a body of water with a current, confined within a bed and stream banks. Depending on its locale or certain characteristics, a stream may be referred to as a branch, brook, beck, burn, creek, "crick", gill , kill, lick, rill, river, syke, bayou, rivulet, streamage, wash, run or...
in the Canterbury
Canterbury, New Zealand
The New Zealand region of Canterbury is mainly composed of the Canterbury Plains and the surrounding mountains. Its main city, Christchurch, hosts the main office of the Christchurch City Council, the Canterbury Regional Council - called Environment Canterbury - and the University of Canterbury.-...
region of New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
's South Island
South Island
The South Island is the larger of the two major islands of New Zealand, the other being the more populous North Island. It is bordered to the north by Cook Strait, to the west by the Tasman Sea, to the south and east by the Pacific Ocean...
.
Characteristics
Its headwaters are in the Hunter HillsHunter Hills
Hunter Hills is a neighborhood located west of downtown Atlanta, Georgia, United States. Its motto, "One Community, One Family", has been its cornerstone since 2001. The neighborhood is encompassed in the 30314 zip code. Hunter Hills shares borders with Mozley Park, Dixie Hills and West Lake...
, foothills of the Southern Alps
Southern Alps
The Southern Alps is a mountain range extending along much of the length of New Zealand's South Island, reaching its greatest elevations near the island's western side...
, and its catchment
Drainage basin
A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...
area is 550 km². The catchment receives approximately 1,000 mm of rain annually. In its upper reaches, the river has two branches, the North Branch and South Branch, which join together at Waihao Forks. The river is well defined, but when it nears the coast, it becomes a braided river
Braided river
A braided river is one of a number of channel types and has a channel that consists of a network of small channels separated by small and often temporary islands called braid bars or, in British usage, aits or eyots. Braided streams occur in rivers with high slope and/or large sediment load...
and has a floodplain
Floodplain
A floodplain, or flood plain, is a flat or nearly flat land adjacent a stream or river that stretches from the banks of its channel to the base of the enclosing valley walls and experiences flooding during periods of high discharge...
of 25 km². When it reaches the coast, the river turns and flows northwards, being joined by the Waimate Creek
Waimate Creek
Waimate Creek is a natural watercourse in the southern Canterbury region of New Zealand's South Island. Its original Māori name was Te Waimatemate, which means "slowly moving waters".- Catchment :...
before discharging into the Wainono Lagoon
Wainono Lagoon
Wainono Lagoon is a shallow lake in the southern Canterbury region of New Zealand's South Island. A number of rivers flow into the lagoon, including the Hook River from the north and the Waihao River from the south...
in Studholme
Studholme
Studholme is a locality in southern Canterbury in New Zealand's South Island. It is named after Michael Studholme, a pioneer European settler who arrived in the area in 1854.- Geography :...
, a locality to the east of the town of Waimate
Waimate
WaimateUrban AreaPopulation:2,835 Extent:Territorial AuthorityName:Waimate District CouncilPopulation:7,206 Land area:3,582.19 km² Mayor:John ColesWebsite:...
. However, a culvert known as the Waihao Box has been cut into the gravel berm
Berm
A berm is a level space, shelf, or raised barrier separating two areas. Berm originates in the Middle Dutch and German berme and came into usage in English via French.- History :...
that separates the river from the Pacific Ocean
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
to provide permanent sea access.
Crossings
The river is crossed by two major roads. State Highway 1State Highway 1 (New Zealand)
State Highway 1 is the longest and most significant road in the New Zealand roading network, running the length of both main islands. It appears on road maps as SH 1 and on road signs as a white number 1 on a red shield, but it has the official designations SH 1N in the North Island, SH 1S in the...
crosses it near the coast between Willowbridge and Morven, while State Highway 82
New Zealand State Highway network
The New Zealand State Highway network is the major national highway network in New Zealand. Just under 100 roads in both the North and South Islands are State Highways...
crosses it inland at Waihao Forks. Near the State Highway 1 crossing, it is also crossed by the Main South Line
Main South Line
The Main South Line, sometimes referred to as part of the South Island Main Trunk Railway, is a railroad line that runs north and south from Lyttelton in New Zealand through Christchurch and along the east coast of the South Island to Invercargill via Dunedin...
railway, and inland, it was formerly crossed by the Waimate Gorge Branch
Waimate Branch
The Waimate Branch was a branch line railway built in southern Canterbury, New Zealand to link the Main South Line with the town of Waimate, the centre of the surrounding rural area. It opened in 1877 and operated until 1966; for some of this time, it included an extension to Waihao Downs that was...
. This branch line
Branch line
A branch line is a secondary railway line which branches off a more important through route, usually a main line. A very short branch line may be called a spur line...
closed in 1953 and the bridges have been removed.
Uses
Agricultural activity occurs the length of the river and it is thus a source of irrigation. It is also used for recreational purposes. Fishers visit the river to fish for brown troutBrown trout
The brown trout and the sea trout are fish of the same species....
. It is also followed by a walkway for approximately 5 km near Waihao Forks.
Events
The river has been prone to flooding, with eighteen major flooding events occurring in the 20th century. The only decades during which major floods did not occur were the 1910s and 1970s, and major floods occurred every year from 1950 to 1953. Environment Canterbury and the local council have implemented strategies to reduce flooding, including the maintenance of stopbanks, managing the riparian zoneRiparian zone
A riparian zone or riparian area is the interface between land and a river or stream. Riparian is also the proper nomenclature for one of the fifteen terrestrial biomes of the earth. Plant habitats and communities along the river margins and banks are called riparian vegetation, characterized by...
to lower erosion, and restricting development to mitigate damage.
In 2000, two special needs students aged 13 and 15 drowned while on a school trip to Black Hole, a swimming hole on the Waihao River. This event stimulated a re-assessment of school policies, and partly as a response to the incident, new safety guidelines were issued by the Ministry of Education
Ministry of Education (New Zealand)
The Ministry of Education , is the primary state sector organisation of New Zealand responsible for New Zealand's education system...
. In 2004, the mothers of the students sued the high school for breaching its duty of care to the students; the case was settled out of court in September 2007.