Waimakariri River
Template:Short description Template:Use dmy dates Template:Use New Zealand English Template:Infobox river The Waimakariri River is one of the largest rivers in Canterbury, on the eastern coast of New Zealand's South Island. It flows for Template:Convert in a generally southeastward direction from the Southern Alps across the Canterbury Plains to the Pacific Ocean.
The river rises on the eastern flanks of the Southern Alps, eight kilometres southwest of Arthur's Pass. For much of its upper reaches, the river is braided, with wide shingle beds. As the river approaches the Canterbury Plains, it passes through a belt of mountains, and is forced into a narrow canyon (the Waimakariri Gorge), before reverting to its braided form for its passage across the plains. It enters the Pacific north of Christchurch, near the town of Kaiapoi.
Instead of being unoccupied Crown land as are most New Zealand river beds, the bed of the Waimakariri River is vested in the Canterbury Regional Council (Environment Canterbury).<ref>Waimakariri River Improvement Act 1922, Section 17(1) – Parliament of New Zealand.</ref>
Name
The name Waimakariri comes from the Māori words Template:Lang, meaning water, and Template:Lang, meaning cold.<ref>Template:Cite book</ref> The river was briefly renamed as the Courtenay River in 1849 by the chief surveyor of the Canterbury Association, Joseph Thomas, in honour of Lord Courtenay. However, this name quickly fell into disuse in favour of the traditional Māori name.<ref name=Blain>Template:Cite book</ref><ref>Template:Cite book</ref> The Waimakariri is colloquially referred to as the 'Waimak', a shortening of the Māori name.<ref name=Logan>Template:Cite book</ref>
Geography
The source of the Waimakariri is located in the Southern Alps, at the head of a valley to the west of Arthur's Pass, where it is primarily fed by snow melt and glacial runoff. The river flows in a southerly direction, before turning east around the base of Mount Stewart. The river at this stage becomes braided, and is joined by the Bealey River as it flows across wide shingle beds.
As the river is joined by the Esk River, the Waimakariri river is forced into a narrow series of gorges and ceases being braided. This continues as the river flows through the foothills of the Southern Alps, and its valley is used by the Midland Line railway as part of its traverse of the Southern Alps. The river exits the foothills at the Waimakariri Gorge, at which point it again expands to a braided system.
Once on the Canterbury Plains, the Waimakariri flows in a roughly east-south-easterly direction towards the Pacific Ocean. As with other braided river systems, the main channels frequently change within the primary riverbed, especially during periods of high flow rates. Geological evidence indicates that this mobility has extended to the river itself in the past, at times flowing through the current location of Christchurch into what is now the Avon Heathcote Estuary, and in a different era flowing into Lake Ellesmere / Te Waihora, to the south of Banks Peninsula.<ref>Waimakariri River, An important asset to the region Template:Webarchive, Environment Canterbury website, retrieved 18 April 2008.</ref> To protect Christchurch and other settlements near the river, multiple flood protections have been constructed either side of the river since European settlement, dating as early as the Canterbury Rivers Act 1868.<ref>Template:Cite web</ref>
The river currently reaches the Pacific Ocean just to the north of Christchurch, entering Pegasus Bay by way of Brooklands Lagoon. The Waimakariri marks one of only a few breaks in the roughly Template:Convert length of Pegasus Bay. Along with two other rivers which enter Pegasus Bay (Ashley River / Rakahuri and Waipara River), the Waimakariri is almost entirely responsible for the sediment which forms the bay and its coastal plain.<ref>Template:Cite journal</ref>
Waimakariri River Regional Park
Template:Main Environment Canterbury manages a regional park covering Template:Convert including the Waimakariri River bed and land on the river margins, to allow for recreation and conservation activities in addition to flood protection.<ref>Template:Cite web</ref><ref name="ecan-official">Template:Cite web</ref> The first stages of the regional park were opened in 2005.<ref>Template:Cite web</ref> The park is divided into sections with different characteristics, and can support a range of activities including walking, picnicking, trail running, mountain biking, fishing, gamebird hunting and horse riding.<ref name="ecan-official" /> There are 14 mountain bike trails.<ref>Template:Cite web</ref>
Ecology
As one of the largest rivers on the Canterbury plains, the Waimakariri is an important habitat for wildlife, including many endangered species of plants and animals. The dry sections of riverbed are home to black-fronted terns, where braids in the river provide a natural barrier to predators.<ref name="ECan Biodiversity">Template:Cite web</ref> The river and its tributaries are home to native species, including crayfish / kōura, New Zealand longfin eel, short-finned eel, lamprey and many species of invertebrates. The river is one of the few remaining habitats for the critically endangered Canterbury mudfish (kowaro), which previously inhabited wetlands across the Canterbury plains, while a portion of its riverbank is home to one of only two known remaining populations of Olearia adenocarpa.<ref name="ECan Biodiversity"/>
Introduced fish are common along the entirety of the Waimakariri River, making the river a popular location for fishing. As with most of New Zealand, this primarily includes brown and rainbow trout, as well as Chinook salmon (Oncorhynchus tshawytscha).<ref>Template:Cite web</ref> The salmon population dates to the early 1900s, when they were introduced from California, and results in large salmon runs near the river mouth in summer.<ref>McDowall, R. M. (1990) New Zealand freshwater fishes: a natural history and guide. Heinemann-Reed, Auckland, 553 p.</ref>
Development
In 1923 the river was mainly investigated for a hydroelectric dam to supply electricity to Christchurch. It received support from the community but the dam was never built since the Government offered inexpensive electricity from the Lake Coleridge scheme.<ref>Template:Cite news</ref>
The Central Plains Water Trust is proposing to take Template:Convert of water from two points on the Waimakariri River as part of the Central Plains Water enhancement scheme.<ref>Central Plains Water Trust applications for resource consent Template:Webarchive Environment Canterbury Resource Consents webpage, retrieved 6 October 2007.</ref>
Pollution
In 2007 the Waimakariri was ranked as one of the ten most polluted of the larger rivers in New Zealand.<ref>Template:Cite web</ref> Some of the pollution was caused by liquid wastes from industries such as a meat processing plant and wool scourers in the vicinity of the river. The wastes were discharged directly into it but as of 2012 it was piped to the municipal sewage treatment plant. There had been some non-compliance issues with the resource consents for water discharge.<ref>Template:Cite web</ref>
Cultural references
The Waimakiriri River is described in several works by author Ruth France. Her poem "After Flood", published under the pseudonym "Paul Henderson", describes "the alive / Roar of the river loud on the loose", and as being an "age-long wanderer, age-wily".<ref>Template:Cite book</ref> Her novel, Ice Cold River (1961), describes the flooding of a family farm at Christmas after the Waimakariri River bursts through a stopbank:
The water advanced so slowly and quietly that it seemed no more than the tide making in an estuary backwater.... [Q]uite suddenly, the lake of water seemed to lift itself, hurled itself over the garden and against the house in a wave that thumped as did a blasting operation at a distance. Immediately the house was surrounded, and the wave went on, eating up the fields with rapid teeth of dirty foam, in which sticks and grass and debris turned over, were engulfed, and reappeared in an endless sucking whirlpool.<ref>Template:Cite book</ref>
- REDIRECT Template:Clear
Template:Redirect category shell
Bridges
From upstream to downstream, the current bridges are:
| Name | Coord | Type | Notes |
|---|---|---|---|
| Waimakariri Falls | Template:Coord | Suspension foot bridge | Adjacent Waimakariri Falls Hut |
| Bealey Bridge | Template:Coord | Single lane road bridge | On State Highway 73 |
| Midland Railway Bridge 42 | Template:Coord | KiwiRail bridge #42 | On Midland Line |
| Mount White Bridge | Template:Coord | Single lane road bridge | |
| Waimakariri Gorge Bridge | Template:Coord | Road bridge | Category II historic place<ref>Template:NZHPT</ref> |
| SH1 Waimakariri Bridges | Template:Coord | Twin three-lane road bridges | On State Highway 1 |
| Main North Road bridge | Template:Coord | Two lane road bridge | |
| Main North Line bridge 17 | Template:Coord | Rail bridge | On Main North Line |
- Bridges across Waimakariri River
-
Waimakariri Falls Bridge
-
Bealey Bridge
-
Midland Line bridge
-
Mount White Bridge
-
Waimakariri Gorge Bridge
-
SH1 bridges (looking north)
-
Main North Road bridge
-
Main North Line bridge
References
External links
- Waimakariri River Regional Plan at Environment Canterbury
- The Waimakariri River as a water resource. Dalmer, 1971
Template:Waimakariri River Template:Waimakariri District Template:Arthur's Pass National Park