Clutha River

Clutha River Mata-Au, Molyneux
Upper Clutha Valley, looking upriver toward the Southern Alps
Clutha River basin (Interactive map)
Etymology	Mata-au: current in the water. Clutha: from Cluaidh, the Scots Gaelic name for the River Clyde
Native name	Mata-Au (Māori)
Location
Country	New Zealand
Region	Otago
Settlements	Wānaka, Cromwell, Clyde, Alexandra, Roxburgh, Balclutha
Physical characteristics
Source	Mount Brewster
• location	Southern Alps
• elevation	1,540 metres (5,050 ft)
Mouth	Pacific Ocean
• coordinates	46°21′S 169°48′E / 46.350°S 169.800°E / -46.350; 169.800
• elevation	Sea level
Length	338 km (210 mi)
Basin size	c. 21,000 km2 (8,100 sq mi)
Discharge
• average	614 m3/s (21,700 cu ft/s)
Basin features
Progression	Makarora River → Lake Wānaka → Clutha River → Pacific Ocean
Tributaries
• left	Hāwea River, Lindis River, Manuherikia River, Beaumont River, Tuapeka River
• right	Cardrona River, Kawarau River, Pomahaka River, Waiwera River
Waterbodies	Lake Wānaka, Lake Dunstan, Lake Roxburgh
Islands	Inch Clutha

The Clutha River (Māori: Mata-Au, officially gazetted as Clutha River / Mata-Au) 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 surounding areas. It is the highest volume river in New Zealand, and a discharging mean flow of 614 cubic metres per second (21,700 cu ft/s).^[1][2]

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 the Clutha catchment.^[3] It has the biggest catchment and outflow in New Zealand. About 6% of all water in the South Island discharged by the Clutha River alone. With a mean discharge of approximately 500 m³ (18,000 cu ft), a catchment area of around 22,000 km² (8,500 sq mi). An economically significant river for the country. The Clutha River encompasses two hydropower stations, which provides 14% of 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 the nearby plate boundary, defined by the Alpine Fault.^[3]

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.