Cooper Creek

Cooper Creek
Coopers Creek
River
Cooper Creek Crossing in Innamincka, South Australia
Country	Australia
State	Queensland and South Australia
Tributaries
- left	Thomson River
- right	Barcoo River
Mouth
- location	Lake Eyre, Far North, South Australia
Length	1,300 km (808 mi)

Cooper Creek (28°23′S 137°41′E / 28.383°S 137.683°E / -28.383; 137.683) is one of the most famous and yet least visited rivers in Australia. It is also known as Cooper's Creek or the Barcoo River and is one of three major Queensland river systems that flow into the Lake Eyre Basin. The flow of the creek depends on monsoonal rains falling months earlier and many hundreds of kilometres away in eastern Queensland.^[1] At 1300 km in length it is the second longest inland river system in Australia after the Murray-Darling system.^[1]

History

Charles Sturt named the river in 1845 after Charles Cooper, the Chief Justice of South Australia.^[1] It was along Cooper Creek that the explorers Burke and Wills met their deaths in 1860. John King survived the expedition with the assistance of friendly aboriginals. Only ten years after the explorers death homesteads were being established on the watercourse. A station at Innamincka was the first permanent settlement in the area.^[1]

By 1880 the reliable water source had attracted more settlers to the point where the whole area was taken up and stocked with cattle.^[1] This led to the displacement of local Aborigines from their traditional lands. By 1900 the population had reduced to 30 survivors, just 10% of the original number, as influenza and measles took their toll.^[1]

Course

It rises west of the Great Dividing Range on low ground as two central Queensland rivers, the Thomson between Longreach and Charters Towers, and the Barcoo in the area around Barcaldine, about 500 kilometres inland from Rockhampton.

Cooper Creek spreads out into a vast area of meandering ephemeral channels, making its way roughly south into the far south-west corner of Queensland before turning due west into South Australia towards Lake Eyre. In most years, it is absorbed into the earth, goes to fill channels and the many permanent waterholes, or simply evaporates without reaching Lake Eyre.

In very wet years, however, it manages to flood the entire Channel Country and reaches Lake Eyre after flowing through the dry areas of Strzelecki Desert, Sturt Stony Desert and the Tirari Desert.^[2] Studies have clearly shown that, although with a mean annual flow of around 2.3 km³ (ranging at Barcoo from an estimated 0.02 km³ in 1902 to an estimated 12 km³ in 1950) the Cooper carries twice as much runoff as the Diamantina and three times as much as the Georgina, over the past ten thousand years it has reached Lake Eyre much less frequently than those rivers. This is because much more water is absorbed along its course than with the Diamantina or Georgina, but could possibly be also because centennial or multicentennial wet and dry cycles in those basins causing them to regularly reach the lake during wet periods (there is some evidence from terraces around Lake Eyre that this occurred during the Medieval Warm Period). During a flooding event the river upstream of Windorah may be as wide as 40 km.^[2]

Land use

Most of the basin of the Cooper is used for sheep and cattle grazing on natural grasslands: although the extreme east of the basin is relatively wet with averages of over 500mm (20 inches) at Blackall, the rainfall is much too erratic for cropping. The soils are mainly Vertisols or Vertic Torrifluvents and are quite fertile, though generally heavy in texture with a strong tendency to crack due to the erratic rainfall.

See also

Australia portal

• List of rivers of Australia

References

External links

• Aerial Video of the Cooper Creek at Innamincka
• Australian Society for Limnology
• Primary Industries and Resources SA - Cooper and Diamantina
• Floods of Lake Eyre
• Gerald Nanson Channel Country
• Department of the Environment and Heritage