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72-759: Clydevale is a township on the banks of the Clutha River / Mata-Au , in the Clutha Valley, 29 kilometres north-west of Balclutha . The township was established by the New Zealand and Australian Land Company in the 1860s. The company officially named the township in 1863, after the River Clyde in Scotland. French food company Danone operates milk factory at Clydevale, which produces toddler infant formula brand Karicare. A new biomass boiler plant

144-542: A taua for whom he had prepared a trap. Historically, Kāi Tahu travelled upstream the Clutha River to fish for eels and hunt waterfowl . Kāi Tahu used to travel in to the interior of the South Island almost every year and had campsites and burial sites along the Clutha River and its nearby lakes. The mouth of Mata-au was heavily populated, with many permanent and temporary Kāi Tahu settlements throughout

216-455: A discharging mean flow of 614 cubic metres per second (21,700 cu ft/s). The Clutha River played a prominent role in both the Māori and European history of the area. Rivers and valleys were the main transport system used by local Māori to access the interior of the South Island. The 1860s Otago gold rush resulted in the production of approximately 240 tonnes of gold, which was found in

288-454: A drainage basin, and there are different ways to interpret that data. In the unlikely event that the gauges are many and evenly distributed over an area of uniform precipitation, using the arithmetic mean method will give good results. In the Thiessen polygon method, the drainage basin is divided into polygons with the rain gauge in the middle of each polygon assumed to be representative for

360-540: A drainage boundary is referred to as watershed delineation . Finding the area and extent of a drainage basin is an important step in many areas of science and engineering. Most of the water that discharges from the basin outlet originated as precipitation falling on the basin. A portion of the water that enters the groundwater system beneath the drainage basin may flow towards the outlet of another drainage basin because groundwater flow directions do not always match those of their overlying drainage network. Measurement of

432-541: A mean discharge of approximately 500 m (18,000 cu ft), a catchment area of around 22,000 km (8,500 sq mi), and a length of about 340 km (210 mi), which makes it one of the longest rivers in New Zealand. The major tributaries include the Arrow River , Cardrona River , Lindis River , Manuherikia River , Teviot River , Pomahaka River , and the Waitāhuna River . Towns near

504-602: A multi-level hierarchical drainage system . Hydrologic units are defined to allow multiple inlets, outlets, or sinks. In a strict sense, all drainage basins are hydrologic units but not all hydrologic units are drainage basins. About 48.71% of the world's land drains to the Atlantic Ocean . In North America , surface water drains to the Atlantic via the Saint Lawrence River and Great Lakes basins,

576-529: A number of 32 huts and 79 rock shelters present in the area. Around 100 dredges have operated at various times during the area's history in the river bed and nearby gravels, including the present-day gorge to the east of the Old Man Range . The Clutha River and its tributary Kawarau transported alluvial gold across a distance of 200 km (120 mi) in river bed load. A Middle Pleistocene -age ancestral Clutha River delivered detrital gold across

648-502: A result, this caused significant damage downstream. Over 21,000 livestock were lost when waters flooded over 12,000 h (43,000 ks). The Balclutha Bridge collapsed on 13 October. The 1978 flood breached the banks of rivers from the Ōreti in the south to the Tokomairaro . Over 12,000 hectares (30,000 acres) of land was inundated, with the loss of over 21,000 livestock. Towns and areas affected stretched from Makarora in

720-561: Is an order of magnitude lower than on the Main Divide . The mean flow of the Clutha is around 614 cubic metres per second (21,700 cu ft/s), comparable to many much larger rivers. This heavy flow, combined with the relatively small size of the river in global terms, makes the Clutha notoriously fast-flowing. It is often listed as one of the world's most swiftly flowing rivers, alongside Australia's Macleay and Fitzroy Rivers ,

792-487: Is referred to as " watershed management ". In Brazil , the National Policy of Water Resources, regulated by Act n° 9.433 of 1997, establishes the drainage basin as the territorial division of Brazilian water management. When a river basin crosses at least one political border, either a border within a nation or an international boundary, it is identified as a transboundary river . Management of such basins becomes

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864-614: Is the Dead Sea . Drainage basins have been historically important for determining territorial boundaries, particularly in regions where trade by water has been important. For example, the English crown gave the Hudson's Bay Company a monopoly on the fur trade in the entire Hudson Bay basin, an area called Rupert's Land . Bioregional political organization today includes agreements of states (e.g., international treaties and, within

936-659: Is the second longest river in New Zealand and the longest in the South Island . It flows south-southeast 338 kilometres (210 mi) through Central and South Otago from Lake Wānaka in the Southern Alps to the Pacific Ocean , 75 kilometres (47 mi) south west of Dunedin . Gold is in abundance in the Clutha River and its surrounding areas. It is the highest volume river in New Zealand, and has

1008-668: The 2018 New Zealand census , an increase of 84 people (5.5%) since the 2013 census , and an increase of 48 people (3.1%) since the 2006 census . There were 570 households, comprising 879 males and 729 females, giving a sex ratio of 1.21 males per female. The median age was 36.4 years (compared with 37.4 years nationally), with 375 people (23.3%) aged under 15 years, 306 (19.0%) aged 15 to 29, 762 (47.4%) aged 30 to 64, and 165 (10.3%) aged 65 or older. Ethnicities were 84.1% European/ Pākehā , 9.1% Māori , 1.9% Pasifika , 8.0% Asian , and 3.7% other ethnicities. People may identify with more than one ethnicity. The percentage of people born overseas

1080-713: The African Great Lakes , the interiors of Australia and the Arabian Peninsula , and parts in Mexico and the Andes . Some of these, such as the Great Basin, are not single drainage basins but collections of separate, adjacent closed basins. In endorheic bodies of water where evaporation is the primary means of water loss, the water is typically more saline than the oceans. An extreme example of this

1152-723: The Amazon and Atrato Rivers in South America, and the Teesta River in the Himalayas. The highest recorded flow on the Clutha was during heavy storms in 1978, peaking at 4,581 cubic metres per second (161,800 cu ft/s). A 2022 report of the river by the National Institute of Water and Atmospheric Research (NIWA) indicated a result of 12 species of native fish, and 2 species from its tributaries, with

1224-607: The Eastern Seaboard of the United States, the Canadian Maritimes , and most of Newfoundland and Labrador . Nearly all of South America east of the Andes also drains to the Atlantic, as does most of Western and Central Europe and the greatest portion of western Sub-Saharan Africa , as well as Western Sahara and part of Morocco . The two major mediterranean seas of the world also flow to

1296-735: The Mississippi (3.22 million km ), and the Río de la Plata (3.17 million km ). The three rivers that drain the most water, from most to least, are the Amazon, Ganges , and Congo rivers. Endorheic basin are inland basins that do not drain to an ocean. Endorheic basins cover around 18% of the Earth's land. Some endorheic basins drain to an Endorheic lake or Inland sea . Many of these lakes are ephemeral or vary dramatically in size depending on climate and inflow. If water evaporates or infiltrates into

1368-809: The Nile River ), Southern , Central, and Eastern Europe , Turkey , and the coastal areas of Israel , Lebanon , and Syria . The Arctic Ocean drains most of Western Canada and Northern Canada east of the Continental Divide , northern Alaska and parts of North Dakota , South Dakota , Minnesota , and Montana in the United States, the north shore of the Scandinavian peninsula in Europe, central and northern Russia, and parts of Kazakhstan and Mongolia in Asia , which totals to about 17% of

1440-551: The 1860s. With several settlements quickly established along gold-rich rivers such as the Clutha and Kawarau , the rush to Central Otago was the largest in the region's history. A large number of miners' huts also existed during this era along the Clutha River. Roxburgh Gorge had a majority of the huts of this type, but they also occurred in Cromwell Gorge. A 1980 archaeological survey in the Roxburgh Gorge indicated

1512-737: The Andes. The Indian Ocean 's drainage basin also comprises about 13% of Earth's land. It drains the eastern coast of Africa, the coasts of the Red Sea and the Persian Gulf , the Indian subcontinent , Burma, and most parts of Australia . The five largest river basins (by area), from largest to smallest, are those of the Amazon (7 million km ), the Congo (4 million km ), the Nile (3.4 million km ),

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1584-726: The Atlantic. The Caribbean Sea and Gulf of Mexico basin includes most of the U.S. interior between the Appalachian and Rocky Mountains , a small part of the Canadian provinces of Alberta and Saskatchewan , eastern Central America , the islands of the Caribbean and the Gulf, and a small part of northern South America. The Mediterranean Sea basin, with the Black Sea , includes much of North Africa , east-central Africa (through

1656-450: The Clutha catchment . It has the biggest catchment and outflow in New Zealand. About 6% of all water in the South Island is discharged by the Clutha River alone. It has a mean discharge of approximately 500 m (18,000 cu ft) and a catchment area of around 22,000 km (8,500 sq mi) and is an economically significant river for the country. The Clutha River encompasses two hydropower stations, which provide 14% of

1728-596: The Clutha Catchment's rapidly expanding water needs will become more challenging in the future. Located at a maximum elevation of approximately 2,800 m (9,200 ft) on the Main Divide of the Southern Alps, the majority of the river's headwater flows originate from the melting of alpine snow cover and rainfall, with glaciers contributing a minor amount. In inland basins, annual precipitation totals can be less than 400 mm (16 in), while on

1800-812: The Clutha River include Alexandra, New Zealand , Balclutha, Cromwell, Roxbrugh , and Wānaka . The Clutha River extends about 340 km (210 mi), flowing roughly north to south through the Otago Region. The Clutha River's headwaters are located in the Southern Alps , receiving up to 8,000 mm (310 in) of precipitation annually from the west and north west. The Clutha River and its tributaries receive water from three lakes in Otago, Hāwea , Wakatipu , and Wānaka , along with its minor tributaries Arrow, Beaumont, Lindis, Manuherikia, Nevis, Shotover, Talla Burn, Teviot, and Pomahaka. The Clutha River may have taken its current course due to glacial advances in

1872-417: The Clutha River use it as a source for treatment plants to provide communities with potable water. Further dam projects have been proposed for the river, but as of 2012, all have been cancelled. The Clutha provides irrigation for stone fruit orchards and vineyards around Cromwell, Alexandra, and Roxburgh, which grow apples, apricots, nectarines, cherries, peaches and grapes. There are more vineyards in

1944-606: The Clyde Dam in 1982 and was completed in 1993. It was a somewhat controversial project, with opposition and criticism from environmentalists and local residents. Completion of the Clyde Dam took much longer than expected, at a final cost more than 45% higher than the first estimate. The Clyde Dam was one of Robert Muldoon 's and the Third National Government 's " Think Big " projects, an interventionist state economic strategy. Several Local Authorities along

2016-669: The Māori name as "Matou" and "Matua-a", and pronounced it "Mattoo". Māori also referred to the Clutha River as Maranuku . The first appearance of a European name for the Clutha River / Mata-Au was the Molyneux River ( / m ɒ l ɪ n ˌ ə ʊ / ); its mouth was named by Captain James Cook after his sailing master, Robert Molineux. The name is also applied to the small settlement of Port Molyneux . Early maps show Moulineux Harbour in its original spelling, but later maps indicate

2088-619: The South Island to recognise the "equal and special significance" of both the English and Māori names. Māori occupation of the Otago Region began in c.  1250–1300 . Māori learned to hunt the numerous species of moa and burned many of the inland forests. The first iwi in Otago were Waitaha , then Kāti Māmoe ; later came Kāi Tahu . By the end of the fourteenth century, the environment in Otago and Southland (Murihuku) had begun to shift, with podocarp woods retreating and

2160-568: The South Island's hydroelectric power supply to the New Zealand power grid . The Clutha River's first dam was the Nil Desperandum Dam in the Upper Clutha Valley, existing from 1864–66. The Roxburgh Dam was the first substantial dam in the South Island. Construction on the dam began in 1949. Four turbines were installed in 1956–57 and four more in 1960–61. Its installed capacity is 320MW. Construction began on

2232-450: The South Island, a whaling station was established close to the Clutha River's mouth at Port Molyneux , and during this period the sea was the source of almost all of the area's economy. The town of Port Molyneux, located on this bay, was a busy harbour during the 19th century. Its location at the mouth of the Clutha made it a good site for trade, both from the interior and for coastal and ocean-going shipping. A major flood in 1878 shifted

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2304-623: The US, interstate compacts ) or other political entities in a particular drainage basin to manage the body or bodies of water into which it drains. Examples of such interstate compacts are the Great Lakes Commission and the Tahoe Regional Planning Agency . In hydrology , the drainage basin is a logical unit of focus for studying the movement of water within the hydrological cycle . The process of finding

2376-498: The amalgamation of eight small schools, and two other schools merged with it in the 1940s. It became a primary school in 1967. Clutha Valley Primary School opened as a replacement in Clydesdale in 2008. In 2019, plans were announced to demolish the existing school buildings, and rebuild the entire school from scratch. Clutha River The Clutha River ( Māori : Mata-Au , officially gazetted as Clutha River / Mata-Au )

2448-586: The area as "well grassed and watered, a very land of promise" which attracted others to the region. In 1862, gold-rich bars of rocks and gravel were discovered by Christopher Reilly and Horatio Hartley during their winter 1862 expedition up Cromwell Gorge through the waters of the Clutha. They arrived in Dunedin on 15 August, 1862, deposited their 100 oz (2,800 g) of gold, and were rewarded with £2,000. A gold rush began in Central Otago in

2520-499: The area's potential was gradually recognised. Previously, the Kawarau River and the Clutha River running downstream from Cromwell were the primary focus. Māori were aware of gold in the Clutha River but they did not value it. The Clutha River is the South Island's largest river and has the largest catchment and outflow in New Zealand. About 6% of all water in the South Island is discharged through Clutha River alone. It has

2592-406: The basin, it can form tributaries that change the structure of the land. There are three different main types, which are affected by the rocks and ground underneath. Rock that is quick to erode forms dendritic patterns, and these are seen most often. The two other types of patterns that form are trellis patterns and rectangular patterns. Rain gauge data is used to measure total precipitation over

2664-421: The catchment. A 2022 study by Diversity and Distributions revealed that the river is home to a diverse range of Galaxias vulgaris clades; its diversity is likely a reflection of the Clutha River's complex geological processes. The study emphasises the importance of the genome -wide methods to identify species and understand biodiversity in freshwater ecosystems and conservation in the Clutha River. Before

2736-425: The construction of Roxburgh Dam , salmon could be found traversing the length of the Clutha River and spawning as far upstream as Lakes Hāwea and Wānaka. The Clutha is the southernmost recognised salmon river; salmon continue to arrive each spring and summer, though numbers have decreased since the construction of Roxburgh Dam. Common bullies , smelt , and perch are also found in the river. A 1981 assessment of

2808-473: The country's hydropower generation capacity. The Clutha River drains the high mountains of the Southern Alps in the west and passes through a complex topographic system of basins and ranges towards the east before reaching into the Pacific Ocean . A majority of the topographical features of the Clutha River catchment area are a direct result of the late Cenozoic and active tectonic processes that are occurring in southern South Island due to deformation along

2880-430: The discharge of water from a basin may be made by a stream gauge located at the basin's outlet. Depending on the conditions of the drainage basin, as rainfall occurs some of it seeps directly into the ground. This water will either remain underground, slowly making its way downhill and eventually reaching the basin, or it will permeate deeper into the soil and consolidate into groundwater aquifers. As water flows through

2952-441: The drainage area is dependent on the soil type. Certain soil types such as sandy soils are very free-draining, and rainfall on sandy soil is likely to be absorbed by the ground. However, soils containing clay can be almost impermeable and therefore rainfall on clay soils will run off and contribute to flood volumes. After prolonged rainfall even free-draining soils can become saturated , meaning that any further rainfall will reach

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3024-697: The drainage basin to the mouth, and may accumulate there, disturbing the natural mineral balance. This can cause eutrophication where plant growth is accelerated by the additional material. Because drainage basins are coherent entities in a hydrological sense, it has become common to manage water resources on the basis of individual basins. In the U.S. state of Minnesota , governmental entities that perform this function are called " watershed districts ". In New Zealand, they are called catchment boards. Comparable community groups based in Ontario, Canada, are called conservation authorities . In North America, this function

3096-538: The drainage divide line. A drainage basin's boundaries are determined by watershed delineation , a common task in environmental engineering and science. In a closed drainage basin, or endorheic basin , rather than flowing to the ocean, water converges toward the interior of the basin, known as a sink , which may be a permanent lake, a dry lake , or a point where surface water is lost underground . Drainage basins are similar but not identical to hydrologic units , which are drainage areas delineated so as to nest into

3168-434: The exception of upland bully , common river galaxias and roundhead galaxias . All native species are diadromous , meaning that they are recorded from the tributaries, and giant kōkopu and kōaro likely went through the mainstem while on their way to its tributaries. The Clutha River has a limited collection of native species, though it does provide a through route for the many other diadromous species. Brown trout are

3240-435: The ground and along rivers it can pick up nutrients , sediment , and pollutants . With the water, they are transported towards the outlet of the basin, and can affect the ecological processes along the way as well as in the receiving water body . Modern use of artificial fertilizers , containing nitrogen (as nitrates ), phosphorus , and potassium , has affected the mouths of drainage basins. The minerals are carried by

3312-781: The ground at its terminus, the area can go by several names, such playa, salt flat, dry lake , or alkali sink . The largest endorheic basins are in Central Asia , including the Caspian Sea , the Aral Sea , and numerous smaller lakes. Other endorheic regions include the Great Basin in the United States, much of the Sahara Desert , the drainage basin of the Okavango River ( Kalahari Basin ), highlands near

3384-665: The harbour's name was written as "Molyneux", rather than "Moulineux". The river is now commonly known as the Clutha, which comes from Cluaidh , the Scots Gaelic name for the River Clyde in Scotland , which runs through Glasgow . The official name for the river has been Clutha River / Mata-au since the Ngāi Tahu Claims Settlement Act 1998 , a landmark Treaty of Waitangi settlement , which added dual names to approximately 90 geographic features throughout

3456-601: The lower parts of what is presently the Manuherikia Valley near Alexandra. By Christmas 1861, 14,000 prospectors were on the Tuapeka and Waipori fields. The gold rush was short-lived, with most of the alluvial gold played out by 1863, but prospectors continued to arrive, swelling to a maximum of 18,000 miners in February 1864. Mining in the Clutha River upstream from Cromwell became significant after 1900, when

3528-636: The lower stretches of the river. Murikauhaka, a settlement near the mouth of the Mata-au, was at one stage home to an estimated two hundred people. Māori trading groups used the Cromwell Gorge as the main thoroughfare to their pounamu and moa-hunting expeditions to the interior of Otago. Many early Māori archaeological sites have been found in the Cromwell Gorge, featuring moa eggshell fragments. Unlike other Central Otago sites, no burned bones have been found. During early European settlement in

3600-669: The middle to late- Pleistocene , advances that nearly reached Cromwell. It is an economically significant river for the country. The Clutha River encompasses two hydropower stations, which provide 14% of the country's hydropower generation capacity. It drains the largest catchment in New Zealand, which is about 22,000 km (8,500 sq mi) in size, and has an area normalised flow of about 800 mm (31 in). It has an average annual discharge of 530 m (19,000 cu ft). Due to long-standing hydroelectricity commitments and increasing demands for urban water supply and irrigation for horticulture and agriculture , meeting

3672-466: The moa population declining. A few Māori settlements in the region started to lose importance, although several settlements still existed in Central Otago . Several locations along the Clutha River retain the names of Kāti Māmoe chiefs, such as, Taumata-o-Te-Hau , a hill on the north side of the Clutha River, above Balclutha , named after the chief who climbed there and watched for the arrival of

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3744-512: The most encountered fish in the Clutha River, occurring throughout the main river, streams, and nearby lakes. Rainbow trout also appear in the river but in smaller numbers, and they are more common in the lower section of the river compared to the upper stretches. At the minimum, nine species of freshwater-limited Galaxias have been identified in the Clutha River by genetics and morphology . A Nationally Critical species of Galaxias called "Clutha flathead species D" occurs in various parts of

3816-487: The mouth of the Clutha to the north and silted up the port, after which the town gradually dwindled. The first European to visit the Upper Clutha area and to see the inland lakes of Wakatipu , Wānaka and Hāwea was Nathanael Chalmers , who was guided by Chiefs Reko and Kaikōura in 1853. They returned him down the river on a mōkihi , a flax reed open kayak, that they built from flax stems and raupō from

3888-664: The nearby plate boundary, defined by the Alpine Fault . The river is known for its scenery, gold-rush history, and swift turquoise waters. A river conservation group, the Clutha Mata-Au River Parkway Group , is working to establish a regional river parkway, with a trail, along the entire river corridor. The Māori name for the Clutha River is the Mata-Au (sometimes shortened to Matau), meaning 'surface current'. Early settlers sometimes spelled

3960-589: The north to Invercargill in the south. The town of Wyndham was completely evacuated, and the towns of Balclutha , Milton and Mataura were seriously affected with many residents moved. The small settlement of Kelso on the banks of the Pomahaka River was completely abandoned and was not rebuilt once the waters subsided. At its peak, on 15 October, the Clutha's flow was measured at just over 4,500 cubic metres per second (160,000 cu ft/s). A major flood in November 1999 seriously damaged river communities, especially Alexandra . The flooding in Alexandra

4032-418: The rainfall on the area of land included in its polygon. These polygons are made by drawing lines between gauges, then making perpendicular bisectors of those lines form the polygons. The isohyetal method involves contours of equal precipitation are drawn over the gauges on a map. Calculating the area between these curves and adding up the volume of water is time-consuming. Isochrone maps can be used to show

4104-572: The responsibility of the countries sharing it. Nile Basin Initiative , OMVS for Senegal River , Mekong River Commission are a few examples of arrangements involving management of shared river basins. Management of shared drainage basins is also seen as a way to build lasting peaceful relationships among countries. The catchment is the most significant factor determining the amount or likelihood of flooding . Catchment factors are: topography , shape, size, soil type, and land use (paved or roofed areas). Catchment topography and shape determine

4176-404: The river by the Upper Clutha Valley Development with the Ministry of Works and Development emphasised the high-quality waters of the river and very low levels of phytoplankton biomasses present. Several major floods have occurred on the Clutha, most notably the "Hundred year floods" of October 1878 and October 1978. During the October 1878 flood, snow from the Southern Alps began to melt and

4248-461: The river rather than being absorbed by the ground. If the surface is impermeable the precipitation will create surface run-off which will lead to higher risk of flooding; if the ground is permeable, the precipitation will infiltrate the soil. Land use can contribute to the volume of water reaching the river, in a similar way to clay soils. For example, rainfall on roofs, pavements , and roads will be collected by rivers with almost no absorption into

4320-462: The river started to rise. Central Otago experienced widespread flooding and farm buildings were submerged to their rooftops while rivers filled with dead horses and sheep, timber from farms and mine workings, and trees with a diameter of 1 m (3 ft 3 in). A bridge in Clyde collapsed on 29 September, and its wreckage floated down to Roxburgh, where it struck a bridge there. The bridges at Bannockburn, Beaumont and Roxbrugh were swept away. As

4392-439: The runholders who had previously acquired territory up to the Waitāhuna River . When they returned to Dunedin after spending several days exploring the Manuherikia Valley, they submitted an application to the Otago Provincial Government to lease two blocks of land on either side of the Manuherikia River. The total land area was 100,000 acres (40,000 hectares). They brought sheep to the district in 1858. Watson Shennan described

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4464-585: The shores of Lake Hāwea. In 1910, 57 years after the event, Nathanael Chalmers remembered his boat trip through the Cromwell Gorge: "I shall never forget the "race" through the gorge ... my heart was literally in my mouth, but those two old men seemed to care nothing for the current." European "sheepmen" arrived later in the late 1850s, searching for grazing grounds in Otago's interior. Alexander and Watson Shennan set off from Milton (known previously as Tokomairiro) in December 1857 to Central Otago, looking for land to raise sheep. The brothers proceeded farther than

4536-418: The speed with which the runoff reaches a river. A long thin catchment will take longer to drain than a circular catchment. Size will help determine the amount of water reaching the river, as the larger the catchment the greater the potential for flooding. It is also determined on the basis of length and width of the drainage basin. Soil type will help determine how much water reaches the river. The runoff from

4608-415: The time taken for rain to reach the river, while catchment size, soil type, and development determine the amount of water to reach the river. Generally, topography plays a big part in how fast runoff will reach a river. Rain that falls in steep mountainous areas will reach the primary river in the drainage basin faster than flat or lightly sloping areas (e.g., > 1% gradient). Shape will contribute to

4680-477: The time taken for runoff water within a drainage basin to reach a lake, reservoir or outlet, assuming constant and uniform effective rainfall. Drainage basins are the principal hydrologic unit considered in fluvial geomorphology . A drainage basin is the source for water and sediment that moves from higher elevation through the river system to lower elevations as they reshape the channel forms. Drainage basins are important in ecology . As water flows over

4752-401: The upper reaches of the river at Bannockburn , Bendigo , Tarras and Wānaka . Catchment Other terms for a drainage basin are catchment area , catchment basin , drainage area , river basin , water basin , and impluvium . In North America, they are commonly called a watershed , though in other English-speaking places, "watershed" is used only in its original sense, that of

4824-509: The western edge of the catchment, they can surpass 4,000 mm (160 in). The contribution of snowmelt to the annual streamflow of the Clutha River is estimated to be 10% by the time it reaches the Southern Pacific Ocean . This proportion is considerably higher for alpine sub-catchments and large inland basins, rising as high as 30% to 50%. A number of large tributaries originate in Central Otago's semi-arid basins, where yearly precipitation can be as low as 400 mm (16 in), which

4896-468: The world's land. Just over 13% of the land in the world drains to the Pacific Ocean . Its basin includes much of China, eastern and southeastern Russia, Japan, the Korean Peninsula , most of Indochina, Indonesia and Malaysia, the Philippines, all of the Pacific Islands , the northeast coast of Australia , and Canada and the United States west of the Continental Divide (including most of Alaska), as well as western Central America and South America west of

4968-441: Was $ 40,100, compared with $ 31,800 nationally. 207 people (16.8%) earned over $ 70,000 compared to 17.2% nationally. The employment status of those at least 15 was that 795 (64.5%) people were employed full-time, 204 (16.5%) were part-time, and 30 (2.4%) were unemployed. Clutha Valley School is a full primary school serving years 1 to 8 with a roll of 106 students as of August 2024. Clutha Valley District High School opened in 1939 as

5040-447: Was 14.7, compared with 27.1% nationally. Although some people chose not to answer the census's question about religious affiliation, 51.3% had no religion, 39.6% were Christian , 0.6% had Māori religious beliefs , 0.2% were Hindu , 0.9% were Buddhist and 0.7% had other religions. Of those at least 15 years old, 183 (14.8%) people had a bachelor's or higher degree, and 216 (17.5%) people had no formal qualifications. The median income

5112-442: Was attributed to a rise in the riverbed resulting from silt loading in the Roxburgh reservoir behind the Roxburgh Dam , downriver from the town. The 1999 flood had significantly higher water levels in Alexandra than the 1878 flood, despite being only 80% of the volume of the latter. There are two hydroelectric power stations on the Clutha River, the 464MW Clyde Dam and the 320MW Roxburgh Dam , which together provide about 22% of

5184-470: Was installed between 2019 and 2021. The settlement has a war memorial with the statue of a soldier, and a plaque listing local men who died in World War I and World War II . The Clutha Valley statistical area covers 747.35 km (288.55 sq mi) and had an estimated population of 1,780 as of June 2024, with a population density of 2.4 people per km. Clutha Valley had a population of 1,608 at

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