Cooper Creek: Australia's Iconic Inland River System
Introduction
Cooper Creek stands as one of Australia's most remarkable and iconic waterways, weaving through the heart of the continent's arid interior. At 1,420 kilometers (880 miles) long, it ranks as Australia's second-longest inland river system, yet its story is one of paradox and extremes. Despite its name, Cooper Creek is perhaps the only waterway in the world where multiple rivers flow into it to form a creek, creating a unique hydrological phenomenon that has captivated explorers, scientists, and adventurers for generations.
Geographic Overview and Formation
Origin and Course
Cooper Creek rises as the Barcoo on the northern slopes of the Warrego Range in Queensland, flowing northwest to Blackall before being joined by the Alice River. The waterway originates from the western slopes of the Great Dividing Range around Longreach and Charters Towers, where the Thomson and Wilson Rivers converge, flowing through the Queensland Channel Country from Barcaldine as the Barcoo.
After receiving its principal tributary, the Thomson River, the waterway becomes known as Cooper Creek. From this confluence, it continues its meandering journey southwest across the Queensland-South Australia border, eventually heading west past permanent waterholes toward its ultimate destination: Lake Eyre.
The Channel Country
Cooper Creek spreads out into a vast area of anastomosing ephemeral channels, making its way roughly south into the far south-west corner of Queensland before turning due west into South Australia. This distinctive landscape, known as the Channel Country, represents one of Australia's most unique geographical features, where the river creates an intricate network of braided channels across the flat desert plains.
During floods, the Cooper can be 25 miles (40 kilometers) wide at Windorah, with water flow equivalent to three times the amount in Sydney Harbor passing over the Cooper Creek causeway at Innamincka daily during such conditions.
Connection to Lake Eyre
Cooper Creek drains the eastern side of the catchment of the Lake Eyre Basin, which at 1,170,000 square kilometers is the world's third-largest terminal lake system and is thought to be the world's largest salt pan. However, reaching Lake Eyre is far from guaranteed.
In most years, the creek is absorbed into the earth, fills channels and many permanent waterholes and lakes such as Lake Yamma Yamma, or simply evaporates without reaching Lake Eyre. Over the past ten thousand years, Cooper Creek has reached Lake Eyre much less frequently than the Diamantina and Georgina rivers, despite carrying twice as much runoff as the Diamantina and three times as much as the Georgina.
Floods of sufficient magnitude to connect with Lake Eyre are relatively rare; the river reached the lake only eight times during the 1900s, and again in 2011. Most recently, in 2025, abundant rainfall in Queensland caused Cooper Creek to begin filling Lake Eyre from the east in late July.
Climate and Hydrology
An Ephemeral River System
Cooper Creek's defining characteristic is its ephemeral nature. In most years, the Cooper is an ephemeral channel that flows briefly after rainfall, with mean precipitation of only 125 millimeters per year, evaporating long before reaching Lake Eyre. The lower reaches receive a modest annual rainfall of around 150 mm, with average temperatures around 30°C and mean annual pan evaporation of 3,500 mm.
The waterway does not experience regular seasonal floods, and being ephemeral, the creek is still prone to occasional flooding. When these rare flood events occur, they are spectacular. In 1940, a vast area surrounding the Cooper was underwater, with the creek being measured at over 43 kilometers wide.
Flow Patterns and Volume
With a mean annual flow of around 2.3 cubic kilometers, ranging from an estimated 0.02 cubic kilometers in 1902 to an estimated 12 cubic kilometers in 1950 at Barcoo, Cooper Creek's flow is highly variable. The average annual discharge at Currareva is 82 cubic meters per second, though this figure masks extreme variations between drought and flood years.
The flooding rains of summer 2010-11 brought the Cooper into very heavy flood, with the flat topography meaning water took six months to flow the 400 kilometers from Innamincka to Lake Eyre.
Historical Significance
Discovery and Naming
Cooper Creek was explored in 1845-46 by Charles Sturt and Sir Thomas Livingstone Mitchell, with Sturt naming it "Cooper's Creek" after Charles Cooper, the first Chief Justice of South Australia. The naming reflects an interesting geographical misunderstanding: Sturt encountered the creek during a dry year and, seeing only a modest watercourse, deemed it merely a "creek" rather than recognizing its potential as a major river system.
The Burke and Wills Expedition
Cooper Creek's place in Australian history was cemented by its association with one of the nation's most famous and tragic exploration expeditions. The Burke and Wills expedition, originally called the Victorian Exploring Expedition, was organized by the Royal Society of Victoria in 1860-61, with Robert O'Hara Burke leading an initial party of nineteen men and William John Wills serving as deputy commander.
On 11 November 1860, the party arrived at Fort Wills on Cooper Creek, the furthest extent of previous inland exploration. Burke established a depot and divided the party, instructing William Brahe to wait at Cooper Creek with supplies while Burke, Wills, John King, and Charles Gray attempted to reach the Gulf of Carpentaria.
The expedition successfully achieved its primary objective. Burke and his party reached the tidal channels of the Gulf on 10 February 1861, technically fulfilling their objective of crossing the country from south to north, though they were unable to cross dense mangrove swamps to reach the open sea. However, the return journey proved catastrophic.
Gray became ill during the trek southward and died from dysentery on 17 April. When the starving explorers returned to Cooper Creek on 21 April 1861, they found the depot deserted—Brahe's party had left that very morning. In one of Australian exploration's most tragic near-misses, Burke arrived just nine hours after Brahe had departed.
Brahe had left supplies buried at the foot of a coolabah tree, now known as the Dig Tree, with directions carved into the trunk. Despite finding these supplies, a series of miscommunications and poor decisions sealed the explorers' fate. Burke and Wills died within a few days of each other at the end of June 1861.
John King, the sole survivor, accepted the Aboriginal people's offers of assistance and survived to tell the tale. King's journal tells of the kindness of the Yandruwandha people and their treatment of him as 'one of their own' over the next three months until Alfred Howitt found him on 15 September 1861.
Burke and Wills were honored with Victoria's first state funeral on 21 January 1863, attended by approximately 80% of Melbourne's population.
Settlement and Development
Only ten years after the explorers' deaths, homesteads were being established on the watercourse, with a station at Innamincka becoming the first permanent settlement in the area. By 1880, the reliable water source had attracted more settlers to the point where the whole area was taken up and stocked with cattle.
This settlement came at a devastating cost to the Indigenous population. The expansion led to the displacement of local people from their traditional lands, and by 1900 the Aboriginal population had reduced to 30 survivors—just 10% of the original number—as influenza and measles took their toll.
Ecology and Biodiversity
Vegetation
During the Tertiary period, Cooper Creek flowed through an environment of forest, but as Australia dried during the continent's slow drift northward, this environment transformed into a narrow band of coolabah (Eucalyptus coolabah) and lignum (Muelhenbeckia spp.) snaking between the sand dunes and gibber plains of the Strzelecki, Sturt's Stony, and Tirari Deserts.
Further from the coolabah riparian zone and lignum thickets, vegetation becomes dominated by chenopod shrublands and hummock grasslands, with Mitchell grass on the gibber plains and Dodonea species, sandhill wattles, and sandhill canegrass on the dunes.
Wildlife and the "Boom and Bust" Cycle
Cooper Creek supports a remarkable boom-and-bust ecosystem driven by its ephemeral flooding cycles. Long dry periods ('busts') are punctuated by floods of high productivity ('boom' periods), creating one of the most dynamic wildlife spectacles in Australia.
Aquatic Life
When the creek fills with water, invertebrates like brine shrimp quickly breed to supply food for Australia's only inland fishery, an industry that targets golden perch, bony bream, catfish, grunters, and yabbies (a freshwater crawfish).
Waterbirds
The waterbird populations of Cooper Creek are among the most spectacular in Australia. During the 1989-1990 flood, when Cooper Creek ran into Lake Eyre and overflowed into Strzelecki Creek to fill Lake Blanche, there were about 500,000 waterbirds in December 1990, with 138,000 in Lower Cooper, 325,000 in Lake Eyre, and 40,000 in Lake Blanche. Researchers estimate that conceivably there were one million waterbirds during this period, making the area one of the most important for waterbirds in Australia.
Bird species such as Australian pelicans, cormorants, darters, egrets, ibises, grebes, stilts, and the endemic Australian black swans move in to access these riches during floods. Countless duck species join them, including pink-eared ducks, shelducks, hardheads, and grey teals.
During significant flood events, researchers have recorded pelican colonies of 30,000 to 60,000 nests, along with many colonies of ibises, egrets, spoonbills, and cormorants numbering in the hundreds or thousands. Following flooding times, the surrounding areas become resource-rich environments, with increases in rodent numbers and huge flocks of black kites soaring overhead, looking for meals of mice or fish.
Flood Frequency and Wildlife Patterns
Studies using flow data and rainfall over a 100-year period (1885-1995) estimated that the Lower Cooper south of Lake Hope receives water about every 4.5 years, but these floods seldom reach Lake Eyre (only 8 years in 100 years). Water is present in Lake Hope 62% of the time and in Lower Cooper Creek 39% of the time.
Conservation Status
In 2011, the government announced that Cooper Creek would be permanently protected, along with the Georgina and Diamantina rivers, declaring it a wild river under the Wild Rivers Act, protecting ten million acres in western Queensland.
Innamincka Regional Reserve, at 1.3 million hectares, is the primary conservation area on the Cooper, though farming and mining are both allowed in the reserve. Coongie Lakes National Park, within the regional reserve, is a wetland of international importance under the Ramsar Convention and was identified as an Important Birding Area because it supports more than 1% of the global populations of 12 species of waterbirds and waders.
Land Use and Human Activities
Pastoral Industry
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 500 mm at Blackall, the rainfall is much too erratic for cropping. The basin (area 296,000 square kilometers) provides cattle pasturage after floods subside.
Water Resources
The major source of domestic and stock water is the aquifers of the Great Artesian Basin. Projects for irrigated cotton farming were introduced in the 1990s; however, they aroused controversy because of concerns about overusing the available water and damaging the wetlands.
Tourism and Recreation
Cooper Creek has become an increasingly popular destination for outback tourism and recreation. The permanent waterholes provide opportunities for camping, fishing, birdwatching, and experiencing the Australian outback. Towns like Innamincka and Windorah serve as gateways to the creek, offering visitor facilities and access points to this remote waterway.
When major floods occur, biological booms are almost matched by tourism booms as people flock to see the birds and floods, with flights into Birdsville doubling during such events.
Environmental Challenges
Cooper Creek faces several environmental pressures despite its remote location. The creek has faced environmental pressures from pastoral activities and climate change, which threaten its hydrological health and biodiversity.
The potential for upstream water extraction remains a significant concern. Potential irrigation developments in the catchment could divert water from the river and decrease the frequency and flooding of wetlands of the Lower Cooper, resulting in fewer feeding areas and less breeding opportunities for waterbirds.
Cultural Significance
Cooper Creek holds profound cultural significance for both Indigenous Australians and the broader Australian nation. Despite the region's aridity, isolated permanent water sources allowed large populations of Aboriginal people to exist along these inland waterways. The Yandruwandha people, in particular, demonstrated deep knowledge of the land and its resources, knowledge that could have saved Burke and Wills had it been heeded.
For non-Indigenous Australians, Cooper Creek has become embedded in the national consciousness as a symbol of both the harsh realities of the Australian interior and the courage—however misguided—of early explorers. The expedition has become an Australian legend, providing important insights into nineteenth-century attitudes towards the Australian environment.
Conclusion
Cooper Creek stands as one of Australia's most extraordinary natural features—a waterway of paradoxes and extremes. It is a river called a creek, an ephemeral system that occasionally creates spectacular floods, a harsh desert environment that periodically transforms into a teeming wetland sanctuary. Its waters have witnessed both tragedy and triumph, carrying stories of Indigenous wisdom, European exploration, pastoral settlement, and remarkable wildlife adaptations.
Today, Cooper Creek continues to play vital roles: as a critical ecosystem supporting unique biodiversity, as pastoral land sustaining the Australian cattle industry, as a site of historical pilgrimage, and as a reminder of the power and unpredictability of Australia's inland waters. As climate change and water management challenges intensify, Cooper Creek's future depends on balancing these competing interests while preserving its unique ecological and cultural values for generations to come.
Whether flowing in flood or reduced to a chain of permanent waterholes, Cooper Creek remains an icon of the Australian outback—a testament to resilience, adaptation, and the enduring power of water in one of the world's driest continents.
