Longest Rivers - Geoscience Australia Longest Rivers Landforms from Space Longest Rivers The lengths of the 10 longest rivers in Australia were re-calculated in September 2008 by Geoscience Australia using data from the National Topographic Database. The calculations confirmed that Australia's longest single river is the River Murray at 2508 kilometres. However, if the longest tributaries of the Darling River, the Culgoa, Balonne and Condamine, are taken into account its total length increases to 2740 kilometres, making it Australia's longest waterway. The National Topographic Database is a nationally consistent dataset containing a range of topographic features, such as relief and drainage, which has been captured and maintained at a scale of 1:250 000 for the whole of Australia. Use of the database to digitally calculate the longest rivers has resulted in more precise estimates than those available previously. River names in the database are acquired from the place names authorities in each Australian State and Territory or other authoritative sources such as the Murray-Darling Basin Authority . The use of official names only for the latest calculations has resulted in significant differences from earlier calculations.

For example, the 1545 kilometre length of the Darling River is based solely on those river sections called Darling River in the database. Separately named tributaries have not been included because they are not strictly part of the officially named Darling River. As a result, the Darling River is now apparently shorter than previously stated. However, if its major tributaries, the Culgoa, Balonne and Condamine, are included, its total length increases to 2740 kilometres. It is important to note that the new lengths are still only approximations, because they have been measured from a cartographic representation of the rivers, rather than the actual rivers. These are the revised top rivers in rank order: NAME What is the Longest River in Australia What is the Longest River in Australia 02 Sep, 2012 what is 0 Australia is a island nation and one of the largest countries on Earth in terms of total area. It is also considered to be a continent, although sometimes it is combined with the surrounding islands and called Australasia or Oceania. Most of Australia is considered to be semi arid or desert and parts of the country are virtually devoid of water.

Despite this, there are many rivers that run through the country. Let’s find out which of these is the longest. What is the longest river in Australia? The longest river in Australia is the Murray River, also called River Murray in South Australia. The river is approximately 2,375 km (1,476 mi) long and begins in the Australian Alps, which is the highest mountain range in the country. The river drains to the west and forms the border between the Australian states of Victoria and New South Wales before passing into South Australia where it eventually flows into Lake Alexandrina and the Indian Ocean. The largest settlement on the river is the twin cities of Albury and Wodonga with a combined population of approximately 90,000. The following is a map of the Murray River: Did you know? The Murray River is very important to Australia as a source of drinking water and irrigation (much of Australia’s food is grown in the Murray basin). Unfortunately, this has caused a reduction in the water levels of the river and threatens the environment. At the beginning of the decade it was estimated that the river now receives only 58% of the natural flow.

The introduction of carp, a non-native fish species, into the river has caused environmental damage and led to a reduction of native fish in the river. The Murray cod, a much loved native species, is just one of the species that is now considered to be critically endangered. Related Articles How long is Australia's longest river? | Reference.com How long is Australia's longest river? A: Quick Answer The River Murray is the longest river in Australia, with a total approximate length of 1,558 miles. This measurement makes the River Murray the longest single river in Australia, not counting tributaries. Full Answer When the primary tributaries are considered, including the Darling River, Culgoa, Balonne and Condamine, the river's total length becomes 1,703 miles, making it the longest waterway in Australia. The River Murray's total length is measured from its source in the Upper Murray through the Kosciuszko National Park. Its length makes this Australian river the third longest navigable river on a global level, behind the Amazon and the Nile. The River Murray winds through three states: Victoria, New South Wales and South Australia.

There are four major dams along its length, with 16 storage wiers and 15 navigable locks. The Murray River starts as a small stream in the Australian Alps. It winds through steep river banks into Mallee, at which point it makes contact with the desert. This river was used as a water highway for at least half a century, starting in the early 1850s. The biggest canoe race in the world is held annually on this river. The Murray River is home to large redgum forests and ibis rookery along its banks. Australian rivers with regulated flows - the Murray-Darling, Snowy, Hunter, and Ord Rivers | australia.gov.au Australian rivers with regulated flows - the Murray-Darling, Snowy, Hunter, and Ord Rivers Australian rivers with regulated flows - the Murray-Darling, Snowy, Hunter, and Ord Rivers Murray River downstream from Hume Weir, 2007, courtesy of ABC Most Australian rivers are located near the coast. Many of the largest and longest Australian rivers, found in the eastern part of the country, especially in the Murray–Darling Basin, have had their flows regulated by humans.

In a massive engineering scheme, the waters of the Snowy River are diverted to the Murray River. In Northern Australia, the greatest diversion of water is on the Ord River around Kununurra, to provide water for irrigation and hydro-electric power. In comparison, there are wild free flowing rivers in other parts of Australia such as the Daly, the Victoria, the Fitzroy and the Gascoyne in the north-west of Australia, the Oxley River in northern NSW and Queensland, and the Franklin in Tasmania. These wild rivers are free flowing heritage listed rivers which contain sites of international significance. There are also free flowing dry inland rivers, such as the Diamantina, which on occasions flows into Lake Eyre in northern South Australia. The Snowy River Hydro Scheme at Talbingo, NSW, courtesy of MDBA The change to the flow of rivers has mostly occurred with dams and weirs. The damming of the Snowy River, for example, diverts water for use in farms, industry and day-to-day urban living. An irrigation system was introduced on the Murray River as early as 1887.

However, these changes in water management have affected the flow and quality of water in the Murray–Darling and salinity is a major issue. Salinity and changes to the water flow in rivers has affected the plants and wildlife. In the same period when irrigation was introduced in the Murray River, in the Hunter Valley, north of Sydney, there was extensive removal of most of the native vegetation surrounding the Hunter River. This led to erosion and, along with overgrazing and the building of levee banks, has dramatically affected the flow of the Hunter River and the natural river environment. The management of Australia's regulated rivers is now negotiated as part of strategic plans to improve the river's health as well as balance the needs for other uses. The Australian Government measures the health of Australian rivers by their condition before European settlement. As part of collaboration between the federal, state and local governments, as well as catchment authorities, the Murray–Darling Basin Agreement aims to limit salinity in the Murray river and manages programs to ensure free passage by native fish.

Use of rivers – Indigenous and early European settler uses The 'Yuki', 13 foot-long bark canoe made from a Red Gum tree by SA south east Aboriginal Communities, courtesy of ABC Aboriginal people who lived along the banks of rivers used them for many purposes. They fished and hunted and ate the plants that grew in the area. The land beside the rivers was used as campsites. Rivers were also used for transport and recreation by Aboriginal people. There is evidence of Aboriginal occupation and use along the banks of many Australian rivers: burial sites, scarred trees whose bark was used to make canoes, and campsites. Aboriginal occupation on the Murray River goes back 40,000 years at Mungo National Park close by to the Murray River. The early European settlers also used rivers as a transportation system as there were few roads. They used paddle steamers, especially on the Murray River, to transport people and essential supplies as settlements were established. The paddle steamer Canberra on the Murray River near Echuca, 2011 by Kathryn Wells Paddle steamers were used to carry wool, wheat, and other goods up and down the river systems including the Murray, Darling and Murrumbidgee Rivers.

Rivers were the inland highways of Australia until the introduction of railways in the 1850s, although paddle steamers continued on a commercial basis until the 1890s. The first irrigation system on the Murray River was introduced in 1887 by Canadian George Chaffey. This reliable and convenient access to water greatly accelerated European settlement as well as the exploitation of the river's water supply around Mildura in Victoria and Renmark in South Australia. Degraded condition of Australia's rivers in southern Australia The health of Australian rivers is measured against their condition before European settlement. In the Australian 2011 State of Environment report, it was noted that The use of this benchmark does not imply that we should restore inland water ecosystems to their near-original condition – it is simply the condition from which we measure change where we can…. State of the Environment 2011, Inland water , Current state and trends of the inland water environment Salinity Salt affected irrigation channel, courtesy of MDBA The introduction of European farming and water management techniques has had a dramatic effect on the Australian environment. The quality of available water in the Murray–Darling is a growing concern.

Salinity is one of the most serious causes of water degradation facing Australia's rivers today. Saline water in the Murray–Darling Basin filters down into underground aquifers and is a problem for agriculture, regional communities and infrastructure. Water flow The problem of more water being taken out of Australian rivers than is going into them has also created issues with flow. A river needs a certain amount of water to flow properly, to provide the right living conditions for animals and fish, and to provide enough water for plants. The water flow through rivers determines much of the environmental condition of inland rivers. Of course, natural water flow varies according to season. Seasonal rain affects how long, how often and the amount of water that flows in a river. Large variations in river flow are typical in Australia and this can be greatly affected by drought and floods. Hume Dam spilling at 40000 MLday, 2010 by Tony Crawford, courtesy of MDBA Drought-breaking rains in the Murray–Darling and the south-east coast from May 2010 to May 2011 had a dramatic effect on the amount of water stored.

The Murray–Darling went up from 28 per cent capacity to 80 per cent. The south-east coast catchment went up from 34 per cent capacity to 51 per cent. In comparison, with less rain, the south-west coast catchment went down from 38 per cent capacity to 21 per cent. However, natural flows are mainly altered by people developing water resources, such as the building of dams and weirs. People have also diverted rivers, such as the Snowy River, built levees on floodplains, as with the Hunter River, and extracted groundwater from the water basins. Murray Mouth and Coorong, 2004 by Michael Bell, courtesy of MDBA The development of water resources with dams and locks in the Murray–Darling division has caused major changes in the natural flow and flooding regimes. The natural flows support important floodplain wetland systems in the Murray–Darling Basin. It has been calculated that the total flow at the Murray mouth has been reduced by 61 per cent due to humans altering and building water resources along the way: Sediment and nutrients The waters of Australian rivers are also being affected by the addition of certain substances, like sediment and nutrients.

Nutrients are substances, such as fertilisers used on crops, that make plants grow quickly. Nutrients can leak into a river system. Sometimes when there are too many nutrients in a river, an algal bloom will occur. An algal bloom is a large growth of a kind of microscopic plant called algae. When the algae in algal blooms eventually dies, it can kill the other kinds of plants and animals that live in the river. Sediment occurs when dust and dirt resulting from erosion gets into the river water. Erosion is the natural wearing down of land caused by the weather. Removing trees and plants from an area can greatly increase the rate of erosion. Over grazing with large numbers of animals like sheep and cows can also contribute to erosion. More erosion means more sediment and rivers with high amounts of sediment can kill the plants and animals that live in them. The silting up of the Hunter River floodplain and estuary T R Brown, View of Hunters River, near Newcastle, New South Wales , 1812, Copper engraving showing deltaic islands in mouth of river, SLNSW The Hunter River catchment, north of Sydney, is one of the largest in New South Wales and reaches further inland than any other catchment.

Originating in the Mount Royal Range, the river is approximately 300 km long, and enters the sea through its mouth at the port of Newcastle. Before European settlement, the lower Hunter floodplain was covered with thick rainforest: The riverbanks were covered with tall eucalypts and swamp oaks which often extended to the water's edge. Alternating strips of rainforest and naturally clear land across the floodplain, marked floodways and abandoned river channels. Patterson Britton & Partners 1993 in NSW Department of Commerce, Manly Hydraulics Laboratory, Hunter Estuary Processes Study, 2003. Nobby's Island and pier, 23 January 1820 by unknown artist, Watercolour, SLNSW, DG SVIB/10 However, by the late 1830s, most of the cedar forest on the Plains was removed, the floodplain up to Singleton had been claimed by settlers and as a result, upstream of Maitland, the majority of rainforest had been removed.

Whilst there was some riparian bank vegetation downstream of Oakhampton (near Maitland), levee banks began to be constructed in the late 1800s to protect and improve agricultural land. At this time it was one of the most populated parts of New South Wales. Before Europeans arrived, the Awabakal clan of Muloobinba (Newcastle) who lived around the foreshore area and harbour entrance had good hunting and fishing facilities, and the area was popular for mud crabs and shellfish, as indicated by the large middens that have survived. In 1855, at the mouth of the river, Rev L.E. Threlkeld wrote Manual labour is now employed to fill up the space betwixt the Island and the main land so as to form a breakwater for the protection of the harbour at Newcastle, and a great part of the top of Nobby's Island has been taken down. Coal River project, History By 1900 the floodplain vegetation had mostly been removed and backwater lagoons or swamps had silted up to the point where they had become suitable for cultivation.

Newcastle in 1849, water colour by John Rae (1813-1900), SLNSW Dredging began in the 1840s, and was needed on a continuous basis from 1859. By the 1920s, the accumulation of the silt in the Hunter river mouth at Newcastle required dredging to allow access for ships. By 1951, the result of 20-years of dredging and reclaiming land resulted in the formation of a single land mass from what had been the deltaic islands of the lower Hunter. From the 1950s, infrastructure and flood mitigation works continued, aimed at reducing flooding. The Lower Hunter Valley Flood Mitigation Scheme, begun in 1956, led to 160 km of levees and spillways, 140 km of farm drains, 200 floodgates, 30 km of river bank protection works and 40 km of control and diversion banks. This led to a substantial modification to the flow of the river and the shape of the riverbanks.

It was later realised that periodic flooding of rivers and their floodplains is a natural phenomenon which serves to provide water to underground aquifers and replenish layers of silty topsoil on the floodplain, essential for river life, plants and animals. If river channels do not flood then sedimentation occurs and if the river channel becomes narrow, as in the case of the Hunter, and then the energy of any future flood increases – causing further damage. In the 1955 flood, there was a large deposit of sediment over a major area from Oakhampton to Morpeth. Following floods in the Hunter, salt enters the estuary at the river's mouth, and then, over a few months, is transported upstream against the river flow, especially during dry periods. Without proper flushing of the estuary, the water quality of the Hunter wetlands and lagoons is also affected by the lack of oxygen and an increase in algal blooms. In the 1970s concerns were raised by the public about the pollution and the extent of industrial development in the Hunter estuary and, in the 1990s, the rehabilitation of the estuary wetlands commenced.

Plants in the Hunter estuary and wetlands include: mangroves, saltmarsh, common reed swamps, Casuarina glauca (she oak) and Melaleuca spp. (paperbark) stands and remnant forests. Riparian fauna includes fish and prawns but a relatively low number of frogs, reptiles and mammals. There are a relatively large number of threatened species. The Hunter estuary provides habitat for at least 23 threatened bird species, one amphibian, seven mammals and two floral species. Irrigation and piped water from rivers Morgan-Whyalla pipeline, South Australia, courtesy of MDBA In the First National Survey of Water Use in Australia, 1981, over 74 per cent of water use was for irrigation compared to 8 per cent for other rural uses, 10 per cent for urban, commercial and domestic purposes and 8 per cent for industry and other activities. No other developed country uses such a high proportion of its water for irrigation and other rural uses. Over two-thirds of river water for irrigation is used for pasture and cereal production whilst a small amount is used for fruit and vegetables.

Irrigation can range from individual farmers pumping water from a stream to large private and government irrigation schemes which are found in all states, especially in the Murray Valley. However nearly all irrigation is dependent upon government-built and operated water storages. Over three quarters of these storages are in the Murray–Darling Basin. Water piped from the Murray River supplies over 75 per cent of Adelaide's water in dry years. Other cities have also had to look to rivers further afield to supplement their water supplies. Melbourne draws on the Thomson River and Sydney on the Shoalhaven River. Industrial use of water is highly localised in centres such as Newcastle and the Hunter Valley, Sydney, Wollongong, Melbourne and Geelong. Irrigation and hydro-electric power – The Snowy River Snowy River, Illawong, courtesy of NSW Office of Water The Snowy River starts in the Australian Alps in New South Wales and is part of the Snowy River Basin area in south-east NSW . The Snowy is fed by one of the largest run-offs in Australia and is one of the largest snowmelt rivers in Australia. Its natural flow runs south until it reaches the ocean at Marlo in eastern Victoria.

Along the way, it passes through the Snowy River National Park. However the flow of the Snowy River is diverted, and only half of the Snowy's water reaches the ocean. The other half is diverted through a series of tunnels and pipes so that it flows into the Murray and Murrumbidgee rivers instead. This diverted water is used mainly for irrigation. As it flows toward the Murray and the Murrumbidgee, the water passes through a series of hydro-electric power stations, which generate electricity. The Snowy Mountains Hydro-electric Scheme was constructed by Australia's post war migrants as part of the changing face of Australia. The alteration of natural river flows through the construction of dams and weirs, and erosion from land clearing, affect riverine health and contribute to water quality problems such as changes to water temperature. There has been a significant decline in the aquatic biodiversity of the Snowy below the town of Jindabyne where the river has been dammed. At the same time, the Snowy River is identified as being of high conservation value.

In October 2000, the NSW, Victorian and Australian Governments agreed to release environmental flows to the Snowy River in four stages to help preserve the water resources in river and groundwater systems. The river has mythical status as part of early European history with Banjo Patterson's poem The Man from Snowy River telling the story of a man whose skill as a horse-rider allows him to ride through mountainside country to recapture an escaped horse. Lower Ord system around Kununurra, Western Australia The greatest diversion of water in Northern Australia occurs in the Lower Ord system around Kununurra, to provide water for irrigation and hydro-electric power. The level of use of water diverted for irrigation is low, but hydropower demand can require release of more than half of all inflows to Lake Argyle. Of note, the creation of Lake Argyle and Lake Kununurra through regulation of the Ord River led to their listing as Wetlands of International Importance under the Ramsar Convention.

Northern Australia Land and Water, Science Review, full report, Water Resources in northern Australia , October 2009 The Murray–Darling River Basin A river catchment is the area of land that surrounds a river and all of its tributaries, from the headwaters to the mouth. The river basin includes all the underwater aquifers and related springs. The Murray–Darling Basin measures over one million square kilometres, which is almost one-seventh of all the land in Australia. When measured from its source in Queensland to its mouth in South Australia, the Murray is over 2,500 kilometres long. The Murray River and its main tributary, the Darling River, are the two main rivers in the Murray–Darling River Basin. The Murrumbidgee Aerial rice sowing in the Murrumbidgee Irrigation Area near Griffith, NSW, 1989. Image courtesy of the CSIRO Land and Water Murrumbidgee means 'big river' in the local Aboriginal language. The Murrumbidgee is one of the largest and most significant tributaries of the Murray. It has one of the largest run-offs for water collected because of its sources located in the Australian Alps.

It flows for 1485 kilometres from the Alps through the Australian Capital Territory (ACT) and then through the Riverina region of New South Wales to the point where it enters the Murray River. The Riverina is one of Australia's most productive farming and agricultural areas. The farms in the Riverina area are reliant on the Murrumbidgee as a water source. In 2007, the Murrumbidgee Irrigation Area produced $800 million in farm produce. The Murray River or Barmah Little Rushy Swamp, Barmah Forest The first Europeans to encounter the Murray were Hamilton Hume and William Hovell, who explored the rivers west of the Great Dividing Range to see if they flowed into the ocean, or into a great inland sea. They named the river the Hume. However six years later, Captain Charles Sturt came upon the river and named it after Sir George Murray, not realising that it was the same river that Hume and Hovell had already named. Moreover, it was already known as Bama or Barmah by its Indigenous inhabitants, the home of a great living serpent.

The Murray River valley was transformed by clearing of native vegetation for the production of crops and livestock. Red gum forests along the rivers were felled for timber, burnt for firewood and cleared for farms and towns. Grazing by livestock along the river banks prevented regeneration. The clearing ‘has allowed more rainfall to move down through the soil, filling the underground gravel and sand beds until they are now overflowing, forcing salty groundwater to the surface and into the River'. Irrigation enabled a massive increase in agricultural production but, at the same time, this increased waterlogging of the soil and salinization. Aboriginal burial sites and midden areas have been flooded by dams. Levees have been built to keep the River in its channel and protect adjacent farms and towns. The wetlands and floodplain beyond the levees are now alienated from the River, reducing habitat for fish and waterfowl. The Murray: A River Worth Saving The Murray has also been important for recreation and tourism with the Murray being continuously navigable for 1986 kilometres from Goolwa to Yarrawonga. A prized fish, the Murray Cod can easily grow up to 1.8m in size and is much sought.

The Murray–Darling Basin Authority Construction begins on the Hume Dam and Weir in 1919 Following the introduction of irrigation in 1887 and a succession of dry years from 1895 until 1902, three Premiers from NSW, Victoria and South Australia agreed in 1911 to appoint engineers to report and recommend on the use of water from the River Murray and its tributaries. The River Murray Waters Agreement (later changed to The Murray–Darling Basin Agreement) was ratified in 1915 by the Australian and state governments by Acts, and proclaimed on 31 January 1917 by the Australian Government. The Agreement set out the shares of water available to each of the states, funding and construction of works, and a Commission to administer the provisions of the Agreement, know now as the Murray–Darling Basin Authority (MDBA). Today, the Murray River has four major dams, 16 storage weirs and 14 navigable locks.

The Authority has a responsibility to promote the use and management of the Basin resources in a way that optimises economic, social and environmental outcomes protect, restore and provide for the ecological values and ecosystem health of the Basin ensure the return to environmentally sustainable levels of extraction of water resources. (Murray–Darling Basin Authority, Planning) The Murray–Darling Basin Authority aims to mitigate salinity in the river through schemes that prevent saline groundwater from entering the River Murray. As part of improving the quality of the river, salt interception schemes pump saline water from underground aquifers and dispose of the salt by a process of evaporation and crystallisation. The Authority also manages the Sea to Hume Fishway Program which aims to open up 2,100 km of the River Murray to free passage by native fish. The Darling The Darling River, which runs for approximately 1,545 kilometers, is Australia's second longest river. It starts in the north side of New South Wales and converges with the Murray River at Wentworth.

Darling River and the Brewarrina stone fish traps, Baiame's Ngunnhu Baiame's Ngunnhu, stone fish traps on the Barwon River near Brewarrina, NSW, courtesy of Department of the Environment. One of its tributaries, the Barwon River at Brewarrina, has one of the river's most significant features: its Aboriginal fish traps, known in the local Aboriginal language as Baiame's Ngunnhu. It is believed that Ngemba, Wonkamurra, Wailwan and Gomolaroi people have shared and maintained the traps for thousands of years. The traps are believed to be at least 40,000 years old, possibly the oldest surviving human-made structure in the world. Consisting of river stones arranged to form small channels, the traps directed fish into small areas from which they could be readily plucked. The traps form a complex net of linked weirs and ponds along 500 metres of the river. They operate at varying water heights and can be altered to suit seasonal changes. Indigenous people use their expert knowledge of fish species and the environment to maximise their catch.

Brewarrina Ngemba Billabong has been declared a World Conservation Union (IUCN) Category V and VI protected area. It was declared an Indigenous Protected Area in November 2010. The ready availability of fish made Brewarrina one of the great inter-tribal meeting places of pre-European eastern Australia. The design of the traps however did not alter the flow of the river. Ebb and flow The questions about both the flow of a river and also the issue of preventing erosion upstream are a critical part of managing regulated rivers. How much flow is necessary for a river's health to combat salinity and algae needs to be balanced with how much water we need from dams for agricultural production. More questions about erosion, deforestation and the deposit of sediment are also considered in managing a regulated river to ensure that the river meets the needs for a sustainable future. Flows and floods are now understood to generate life through stimulating ecosystems. Ebb and flow is both the life of the river and its people. Useful links Australia's wild rivers | australia.gov.au Australia's wild rivers Australia's fossil past Australia's wild rivers Aerial view of the mouth of the Mulgrave River, Queensland.

Image courtesy of the John Oxley Library, State Library of Queensland Accession number: P38. Australia's wild rivers are seen as relatively unaltered by modern human development, and exist in their natural condition – to flow freely without dams or other barriers. However, free flowing rivers have never been void of human activity. Indigenous and other peoples have long engaged in productive activities in and around wild rivers, with a deep knowledge base, awareness and attachment to the life of the river. This heritage tradition and contemporary engagement of Indigenous people has been recognised in heritage protection legislation in Australia. Indigenous people have a significant role to play in the ongoing management, use and conservation of wild rivers. The national importance of wild rivers across Australia was first recognised by the Australian Government in 1992. The Wild Rivers project set out to identify rivers, encourage protection, engage in voluntary management of the whole catchment, and promote the values of wild rivers. The project was guided by water resource management and nature conservation agencies, local government, farmers, conservation groups, Indigenous people and the scientific community. Franklin River, Tasmania, 2013, courtesy of Selmes Films Like other rivers in Australia, wild rivers are highly varied in their makeup.

Wild rivers may exist as a single channel, a channel network, or a network of waterholes and billabongs, as well as having some overland flow. They can exist as perennial (permanently flowing) or non-perennial (seasonally flowing) rivers. Wild rivers can also be characterised by spectacular gorges, waterfalls, deep water holes, and fast and slow flowing channels of water. Aurukun residents fish on the banks of the Archer River, Queensland, 2009 by Tim O' Reilly, courtesy of ABC At the same time, all the biological processes associated with the river and the land surrounding the river, extending to its intimate catchment, must not have been significantly altered by modern or colonial society. The catchment area for a river is the entire river system from its source, all the tributaries and down to its mouth. Australia has 12 catchment divisions. There are 208 major waterways in Western Australian and 48 have been identified as wild rivers. Many of the wild rivers (37) are found in the Kimberley and Pilbara regions of northern Australia.

Some of the large rivers in north western Australia – the Daly, the Victoria, the Fitzroy and the Gascoyne – form catchments which are heritage listed and their mouths contain sites of international significance. Australia's dry inland rivers, such as the Diamantina, which on occasion flows into Lake Eyre in northern South Australia, are some of the last of the world's unregulated dry river systems. Gascoyne River, Western Australia, 2009 by RhysThomas There are also highly valued and protected wild rivers in southern Australia, especially in Tasmania with the Franklin–Lower Gordon Wild Rivers, and in places such as the Oxley Wild Rivers National Park in New South Wales. Northern Australian and Tasmanian inland water environments are generally in good condition.

[In comparison,]… many of Australia's inland water environments in southern Australia, and particularly the Murray–Darling Basin are in a degraded condition...[due to] high levels of water resource development State of the Environment 2011, Inland water, Current state and trends of the land environment Like some of the controversial campaigns in the 1980s for the Franklin–Lower Gordon Wild Rivers, since 2009 there has been much debate about the appropriate resource development and management for Queensland's ten wild river areas, mainly on Cape York. Lake Eyre Basin – part of a unique dry land river system Cooper Creek, a river in the Lake Eyre Basin, 20 October 2010, courtesy of ABC The Lake Eyre Basin is one of the last unregulated or free flowing dry land river systems in the world. When major rains fall and the dry land rivers flood, the rivers can completely transform Australia's desert country into a temporary lush green wetland, bursting with birdlife and brimming with breeding fish. It is one of the most spectacular natural events on the planet.

None of the rivers and creeks of the Lake Eyre basin is permanent but in flood years they spill widely to spark a period of rapid growth and fertility. Long-dormant crustaceans multiply and flocks of waterbirds arrive in huge numbers to feed and raise their young before the waters evaporate. Dan Gaffney, ‘Floods bring mass bird breeding frenzy', 19 May, 2009, UNSW Science About 60 species of birds respond to its call – and six to eight million water birds make the pilgrimage from the Murray and other rivers in South Australia, New South Wales and Queensland. Some travel a thousand kilometers or more. The fresh water and food sources, as fish and crustaceans emerge on a fast-breeding cycle, encourages nest building and egg laying. Pelicans on Lake Eyre by Wayne Lawlor.

Cooper Creek, one of the major rivers in the Lake Eyre Basin, is one of the most unpredictable and variable of all the major rivers in the world: After soaking the soils and replenishing the waterholes, [water] will flow all the way down into Lake Eyre, turning the salt flats once again into a huge inland lake… Pelicans and Yellow-Billed Spoonbills and Black Swans fly over your head. It's a stark contrast to the normally bone-dry, sandy plain. Boom time for the Channel Country rivers of Lake Eyre Basin, 25 March, 2010, The Wilderness Society Cooper Creek, the Diamantina and Georgina rivers were protected by Queensland State Government Wild River legislation in 2010 although this was reviewed in 2012. The sustainable management of the Lake Eyre Basin is assisted by a panel providing world class scientific and technical advice. The panel is part of an Intergovernmental Agreement, the Lake Eyre Basin Ministerial Forum – a joint undertaking of the Australian, Queensland, South Australian and Northern Territory governments that works closely with the Basin community.

The Diamantina River – part of the Channel country One of the main rivers which flows directly into Lake Eyre is the Diamantina River which is 900 kilometres long, about the same length as the Murray River. The Diamantina is a river with its headwaters in Central West Queensland, south-east of Mount Isa and Cloncurry, and west of Winton in the Selwyn Range. The Diamantina River has no main channel but is a series of wide relatively shallow channels. This area is known as the Channel country that forms part of the Diamantina National Park . Floodplain north of Birdsville, courtesy of UNSW Science The Diamantina flows sluggishly in a southwesterly direction through central Queensland to form the Warburton River just past Birdsville. In extremely wet years, the Warburton River flows to Lake Eyre. The Diamantina River basin is approximately 157,000 km² of which most (140,000 km²) is used for agriculture, mostly grazing cattle and sheep. The variable nature of Australia's wild rivers is not seen in isolation from seasonal changes, natural disasters and weather patterns.

Drought, cyclones and flooding rains are intimately associated with Australia's rivers. Since its discovery by Europeans in 1840 until its first recorded filling in 1949, Lake Eyre filling was considered as an isolated, unique and independent event. Only recently have they been looked at as a predictable manifestation of the world-wide atmospheric and oceanic circulation, of which the El Nino-Southern Oscillation (ENSO) is one of the most significant phenomena which affects Australian weather and seasons. Dr Vincent Kotwicki, Lake Eyre Basics, Floods of Lake Eyre Northern Australia and the Timor Sea Basin The northern catchments: the Gulf of Carpentaria, Timor Sea and North Western Plateau divisions, and the northern third of the North East Coast division have many wild rivers. The first permanent water as you travel north from Alice Springs in the Northern Territory is the Katherine River. Its headwaters are in Nitmiluk National Park, it flows through the town of Katherine, and is a major tributary of the Daly River, which flows into the Timor Sea.

Flooding in the streets of Katherine, Northern Territory, 28 January, 1998 by the NT News, courtesy of Bureau of Meteorology. The rivers of the top end, like the Katherine, the Daly and the Victoria River, are prone to seasonal flooding and this has had a significant impact on the communities. Some of the heaviest rainfall and worst flooding over northern Australia occurs when a tropical cyclone crosses the coast and moves inland. On 25–26 January 1998, Tropical Cyclone Les, which had developed over the Gulf of Carpentaria, moved west towards Katherine. Rain fell and continued virtually without a break. By the 28 January, about 400–500mm of rain drenched significant areas of the Katherine, Roper and Daly River catchments. The flooding of the Katherine River was the worst in Katherine's history, eclipsing the previous record (set in 1957) by 0.7 metres. Two metres of water filled the main street, and the whole central business district was inundated. Some 2000 people had to abandon their homes.

Daly River Barra Resort At Daly River town, on 28 January 1998, the river inundated the town and the entire population had to be airlifted in an emergency evacuation to Batchelor, south of Darwin. The floodwaters, fed by heavy rainfall in the wake of Tropical Cyclone Les, continued to rise until 3 February, reaching a peak of 16.8 m, which was the highest level recorded to date for the Daly River. The Katherine, the Daly and the Victoria Rivers like other Top End Rivers attract people fishing for barramundi and other recreational activities. The rivers are also home to saltwater crocodiles, reptiles, cockatoos, feral water buffalo, mangroves, giant bamboos on the Daly, pandanus, and kapok trees. Victoria River The Victoria River, Northern Territory - part of the Timor Sea Drainage Division The Victoria River, at 560 kilometres in length, is the longest singularly named permanent river in the Northern Territory. The Victoria River enters the Timor Sea at the Joseph Bonaparte Gulf. Part of the area adjoining the river mouth has been identified as the Legune (Joseph Bonaparte Bay) Important Bird Area.

The IBA lies between the estuaries of the Keep and Victoria Rivers and is recognised as a site of international importance for bird conservation. It is possible to fly over the wetlands and see this extraordinary diverse floodplain teeming with birdlife. The Legune coastal floodplain, part of the Legune pastoral lease, extends across extensive tidal flats with large areas of mangroves which are not inundated by a flooding river mouth. The Legune wetlands comprise extensive areas of diverse freshwater and saline wetland habitat and are known to support more than 40,000 mixed waterbirds, mostly Wandering Whistling-Ducks and various egrets and herons. At least four waterbird breeding colonies have also been recorded on the floodplain, including the second largest waterbird colony in the Territory. Turtle Point supports high density nesting of the Flatback Turtles and significant aggregations of migratory shorebirds. Northern Territory Government, Sites of Conservation Significance, Legune coastal floodplain Fitzroy River, Western Australia – Mardoowarra, the river of life Just south of the Timor Sea, the Fitzroy River in northwest Western Australia flows into the Indian Ocean.

The Fitzroy River flows for 733 kilometres from the King Leopold and Mueller Ranges into King Sound south of Derby, in a catchment area of nearly 100,000 square kilometres. Its mouth features king tides, some of the most extensive in the world, where there is investment in tidal energy. Traditional owners at Gambanan on the Fitzroy River in the Kimberley, Western Australia, courtesy of Mardoowarra - ‘River of life'. The first European to visit the Fitzroy River was George Grey in 1837 aboard Charles Darwin's vessel, the H.M.S. Beagle. After the establishment of Yeeda station in 1880, other pastoral stations were established during the 1880s, along the Fitzroy river, further upstream including: Noonkanbah, Gogo and Fossil Downs Stations. The traditional owners know the river as Mardoowarra - ‘River of life'. In 2010, the Fitzroy River Catchment Management Plan identified the relatively unregulated water flow of the Fitzroy River as an asset. The river's flow helps to maintain a healthy river system by ‘annual cleansing during floods'.

The management plan recognises that the catchment contains unique ecosystems that are important to protect because of their high levels of biodiversity with rare plants and animals. The river and its vast floodplains are of great spiritual, cultural, medicinal and ecological significance to the Nyikina peoples to the west, and the Walmadjari and Konejandi peoples to the east, who have lived in the area for at least 40,000 years. The Horizontal Falls Kimberley Region In 2011, the Australian Government Environment Minister announced the heritage listing of most of the Fitzroy River catchment: the West Kimberley coast from Cape Leveque to Cambridge Gulf, the Kimberley plateau, the Fitzroy River itself, and land south of the Oscar and Napier ranges. The heritage listing means the protection of wildlife, coastline and Indigenous heritage, and that activities that might impact on those values must first be approved by the Federal Government. It was listed because of ‘Its unique wildlife, stunning coastlines, spectacular gorges and waterfalls, ancient Aboriginal cultural traditions as well as its pastoral and pearling history'.

The Gascoyne River and the Indian Ocean basin The Bibbawarra Crossing Gascoyne River near Carnarvon, 2011 by Alex Hyman, courtesy of ABC Further south and part of the Indian Ocean basin is the Gascoyne River. At 865 kilometres it is the longest river in Western Australia. Its unique features are its huge underground water system. The Gascoyne flows for about 120 days of the year and for the rest of the year, the river flows below the dry riverbed. It is in effect a huge water storage system with the river's aquifers lying below the desert sands. It still has the capacity to flood and residents then have to evacuate. The Gascoyne River rises on Three Rivers Station near the Great Northern Highway, 100 kilometres northeast of Peak Hill, and flows into Shark Bay and the Indian Ocean at Carnarvon. The river is made up of three branches and has 36 tributaries including the Landor and Thomas rivers. Its catchment is sparsely vegetated countryside used mainly for gold mining and sheep grazing. The river flows through many permanent pools that are valuable to both stock and native species.

Some of the main pools located along the river include Tibbingoona Pool, Mutherbokin Pool, and Mibbley Pool. The Franklin–Lower Gordon Wild Rivers, Tasmania Rock Island Bend, Franklin River by Peter Dombrovskis, a Tasmanian Wilderness Society advertisement, 2 March 1983 When the Franklin–Lower Gordon Wild Rivers National Park was accepted for World Heritage listing by UNESCO in 1982, the Western Tasmanian Wilderness National Parks World Heritage Area had satisfied more criteria than any other World Heritage Area. Yet, the Franklin River blockade campaign in Tasmania was one of the most controversial conflicts over the management of a southern river's water resources ever seen in Australian history. In the late 1970s, a campaign aimed at preventing the damming of the river was ignited when the Hydro-Electric Commission (HEC) released a proposal to construct a 180 megawatt power scheme in 1979. The scheme would result in the inundation of 37 kilometres of the middle reaches of the Gordon River and 33 kilometres of the Franklin River valley.

Not long after, in 1982, the Australian Government nominated the Cradle Mountain–Lake St Clair National Park, Franklin–Lower Gordon Wild Rivers National Park and the Southwest National Park for World Heritage listing. The listing was accepted at the December UNESCO meeting on World Heritage. Blockade campaign, Franklin River, 1982 by unknown blog supplied to The Age The World Heritage listing was in conflict with aims of the newly elected Liberal Premier, Robin Gray, who staunchly supported the building of the hydroelectric dam. Gray considered the Franklin River, ‘nothing but a brown ditch, leech-ridden and unattractive to the majority of people'. In June 1982 the newly elected Gray Government revoked parts of the Wild Rivers National Park to commence construction of the dam. In the summer of 1982–83, the nearby village of Strahan became the focus of the largest conservation battle ever fought in Australia: the battle to save the Franklin River. Goanna, a rock band from western Victoria, wrote a song called ‘Let the Franklin Flow' which became an anthem for the conservation battle.

The issue dominated Tasmanian politics throughout the late 1970s and early 80s and caused great rifts between those who supported the construction of the dam and those who sought the preservation of the wilderness values of the region. In 1983, the Hawke Government, which had recently been elected into office on an anti-dam platform, passed regulations forbidding HEC works within the World Heritage Area. Despite this, the HEC continued with the construction of works while the Tasmanian Government's challenge to the validity of the legislation was heard in the High Court. It was the decision of the High Court on the 1 July 1983 which, after a four to three majority ruling, prevented the damming of the Franklin River. Parks Tasmania, Franklin–Lower Gordon Wild Rivers National Park The Tasmanian Government accepted $276 million in compensation from the Australian Government to subsidise the cost of the King and Anthony HEC power schemes. Grants were also provided to assist with the Tasmanian Wilderness World Heritage Area Management Plan with coexisting environmental, Aboriginal, convict and settler heritage values.

River crew Franklin by Matthew Newton, courtesy of Tourism Australia Since that time the park has been recognised for its rich and remarkable heritage as it contains many Aboriginal sites extending back over 36,000 years, as well as for its remote and rugged beauty. The vegetation varies within local vicinities. For example, to the west of the King William Saddle area is high rainfall area, averaging 2500 mm per annum, which supports luxuriant cool temperate rainforest. To the drier east, eucalypt forests and button grass grassland communities are the dominant vegetation types. Visitors to the Franklin–Lower Gordon Wild Rivers National Park can drive through the park, bushwalk on a variety of walking tracks and nature trails, and travel on boats to see the beauty of the wild rivers region. Rafting enthusiasts are warned that the journey is not for amateurs as it can be extremely hazardous, and is only for those who are experienced and sure of their abilities. Rafting the Franklin is done with experienced guides, life jackets and helmets – all necessary ‘if you take on the Franklin, one of the savage rivers that riddle south-west Tasmania like a nest of snakes'.

Oxley Wild Rivers National Park, New South Wales Budd's mare lookout, Oxley Wild Rivers National Park, courtesy of NSW OEH Oxley Wild Rivers National Park, part of the Gondwana Rainforests of Australia World Heritage Area, features rare dry rainforest, dramatic gorges and waterfalls, extensive wilderness areas, wild and scenic rivers, and an amazing array of wildlife. First inscribed as a World Heritage area in 1986 and extended in 1994, the Gondwana Rainforests of Australia has: The most extensive area of subtropical rainforest in the world, large areas of warm temperate rainforest and nearly all of the Antarctic beech cool temperate rainforest. Few places on earth contain so many plants and animals which remain relatively unchanged from their ancestors in the fossil record. The outstanding geological features displayed around shield volcanic craters and the high number of rare and threatened species are of international significance for science and conservation. Environment NSW, Gondwana World Heritage Area Visitors to the area can explore the region by driving along the Waterfall Way as well as bush walking to explore the Apsley Macleay Gorges, one of Australia's largest gorge systems.

Wollomombi, the highest waterfall in New South Wales is part of the Oxley Wild Rivers National Park. Bushwalkers have access to overnight accommodation in heritage listed stockman's huts, as well as the East Kunderang Homestead. Review of wild rivers legislation for Cape York, Queensland Archer River rapids, Cape York, Queensland, 2009 by Glenn Walker, Wilderness Society, courtesy of ABC. Since 2005, 10 regions in Queensland have been declared wild river areas under the Wild Rivers Act . These include Settlement Creek, Gregory River, Morning Inlet, and Staaten River in the Gulf of Carpentaria, and the Wenlock, Archer, Lockhart, and Stewart river basins on the Cape York Peninsula, as well as Hinchinbrook Island and Fraser Island. In a wild river area, new large-scale development projects such as in-stream dams and weirs, surface mining, and intensive agriculture, are subject to certain restrictions. However, other low impact activities such as small-scale commercial fishing, ecotourism, and sustainable industries, are permitted with Government approval.

Queensland, Department of Environment and Resource Management, Wild Rivers Some opponents of the Wild Rivers Act are concerned about how the legislation will affect Aboriginal Traditional Owners who are seeking to develop their land. Lockhart River Aboriginal Shire Council has noted that Aboriginal people have successfully looked after these ‘wild rivers' for thousands of years, and that the river systems continue to be an important part of their culture and everyday lives today.' Aurukun Wetland Charters fishing Indigenous people carry on with activities like camping, fishing, hunting, conducting ceremonies, and traditional fire management as well as small-scale development projects, such as eco-tourism industries, and other developments with water reserves set aside for this purpose. An example is the Wik Projects Ltd enterprise, Aurukun Wetland Charters - using catch and release fishing and eco-tourism. Aurukun is located on the western coast of Cape York at the junction of three pristine rivers - the Archer, the Watson and the Ward.

Together with other river systems lying further south (the Kirk and the Love Rivers), this massive network of rivers forms the Aurukun Wetlands, one of Australia's largest wetland areas covering 1.1 million hectares, and containing some of the best quality coastal wetland habitats in Northern Australia. Aurukun Wetland Charters Murrandoo Yanner of the Carpentaria Land Council believes that: ‘The majority of the people ... would rather have the sustainable rivers so we can continue as we have for thousands of years to draw our food and nourishment from those rivers'. Aurukun Wetland Charters Wild rivers and Indigenous economic development In Queensland is now seen as part of a wider discussion about development options and Indigenous people managing their land within a wild river area. In 2011 a House of Representatives Standing Committee examined Indigenous Economic Development in Queensland as part of its Review of the Wild Rivers legislation, including examples of Indigenous Land Use Agreements (ILUAs) in the Cape York region providing economic opportunities. In discussing the details of wild rivers management, Reconciliation Australia suggests that most people agree that genuine and respectful partnership with Aboriginal communities is vital in managing wild rivers.

Question: What is the longest river in Australia?
Answer: River Murray