Snapshot
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Catchment area
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2% of the Murray–Darling Basin
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Contribution to Basin water
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17%
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Annual stream flow
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2,550 GL per year (Hume Dam unregulated inflow)
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River length
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2,500 km in total; 300 km source to Hume Dam
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Major tributaries
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Victoria: Koetong, Cudgewa, Corryong and Thowgla creeks, Mitta Mitta River
New South Wales: Geehi, Swampy Plains and Tooma rivers, Tumbarumba Creek
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Major towns/cities
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Corryong, Khancoban, Tumbarumba
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Major water storages
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Hume Dam (3,005 GL), Khancoban Pondage (26 GL), Geehi Reservoir (21 GL) and Tooma Reservoir (26 GL)
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Key water users
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Hydro-electricity, urban water supply, stock and domestic
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Summary
The River Murray is Australia's longest river, running a course of 2,500 km from near Mount Kosciuszko in the Australian Alps to the Southern Ocean at Goolwa, in South Australia. The catchment description of the River Murray is split into 3 sections – upper, central and lower.
The upper River Murray catchment takes in the headwaters of the Murray and its many tributaries, and extends about 300 km to the Hume Dam. Located in New South Wales and Victoria, the catchment covers about 2% of the area of the Basin but provides about 17% of the water.
Up to 80% of the upper Murray catchment remains forested, much of which is national park and state forest, encompassing diverse environments from alpine grasslands and wetlands, to heavily timbered forest.
The eastern section of the upper Murray catchment is rugged mountain country and about 100 km from the Murray's source, the mountains give way to steep hills and deep alluvial valleys used for dryland grazing, dairying, forestry and niche horticultural crops. The Snowy Mountains Hydro-electric Scheme is located in the upper Murray (and Murrumbidgee) catchments.
The catchment is sparsely populated however it is a very popular destination for skiers, fishermen, hikers and campers. Tourism is an important sector of the local economy.
The landscape and its water
High in the Australian Alps, about 40 km south of Mount Kosciuszko, 3 springs in alpine grassland give rise to the Murray. The springs form a small stream that flows west and then northwards through the Alpine and Kosciuszko national parks.
The mountain reaches of the River Murray (sometimes called the Indi River) are joined by many mountain creeks and rivers, the most significant being the Swampy Plain River, which also rises high in the mountains. Much of the volume of the Swampy Plain River is gained from the Geehi River, which carries water through the Snowy Mountains Hydro-electric Scheme, including water diverted from the Snowy River.
After its confluence with the Swampy Plain River, some 100 km from its source, the Murray is a wide, swift river that flows through a wide alluvial valley in the foothills of the Great Dividing Range. Other creeks and rivers that rise and merge in the mountains, meet the Murray as it flows through the foothills. The Koetong, Cudgewa, Corryong and Thowgla creeks are major Victorian tributaries of the upper River Murray, and the Swampy Plain and Tooma rivers and the Tumbarumba Creek are the main tributaries on the New South Wales side. The western boundary of the upper Murray catchment is the Hume Dam, with the Murray forming the north arm of the reservoir. The Mitta Mitta River flows into the southern arm of the Hume Dam.
The upper River Murray rises at an elevation of over 1,000 m where snow lies on alpine meadows for several months each year. Average annual rainfall at the head of the catchment is about 1,500 mm. After the river descends the steep ravines and valleys of the western side of the Great Dividing Range, it starts its westward journey down a long and ever-broadening valley across the riverine plains. Elevation at the Hume Dam is 150 m and annual average rainfall is about 700 mm. Rainfall across the catchment occurs throughout the year but the highest falls are in winter and spring.
Surface water and groundwater systems in the catchment range from being highly connected – especially in the mountains – to disconnected. Most upland streams receive flow from fractured granite and sedimentary rock aquifers and alluvial groundwater is associated with the floodplains of some streams and rivers.
People, industry and water use
The upper River Murray and the surrounding mountains, hills and valleys have been important for First Nations culture for at least 21,000 years, however First Nations people did not live in the mountains permanently. Many groups would travel hundreds of kilometres to the region to feast on bogong moths that migrated from Queensland to the southern Australian Alps each spring and summer. These gatherings were also a time to perform ceremonies, share stories, and exchange knowledge and skills. The upper Murray catchment includes the traditional land of the Dhudhuroa, Djilamatang, Ngarigo, Walgalu and Yaitmathang Aboriginal Nations.
After the explorers Hamilton Hume and William Hovell passed through the region in the 1820s, squatters and settlers soon established grazing properties for cattle and sheep, attracted by the reports of good water and fodder. Cattlemen also grazed their livestock on summer pasture in the mountains from as early as the 1840s. The famous Banjo Paterson poem, The Man from Snowy River, is based on the stockman Jack Riley, from Tom Groggin Station in the east of the catchment. For a short time in the late 1800s, gold and tin were mined in the region.
The catchment is sparsely populated with a few small towns providing essential services to residents. These towns include Corryong in Victoria with a population of 1,400 people, and Tumbarumba in New South Wales with 1,800 people (ABS 2011). Khancoban, with a population of 300 people, is the headquarters of the Murray section of the Snowy Mountains Hydro-electric Scheme.
About 80% of the region is forested and largely non-arable. Some of the forested area is commercially managed pine and eucalypt forest for the production of timber and paper. The cleared and settled areas of the region support a range of agricultural enterprises, predominantly cattle and sheep grazing, but also dairying, pasture seed production, wine grapes, and niche crops.
Tourism is a significant industry in the upper Murray catchment with the mountain peaks, valleys and extensive forests providing endless options for outdoor recreation from bushwalking and bird watching, to skiing and trail riding, to fishing and water sports.
The 2008 Water availability in the Murray report by the Commonwealth Scientific and Industrial Research Organisation (CSIRO) was based on the whole Murray catchment, from the mountain headwaters to the Murray Mouth, as well as the lower Darling River catchment, below the Menindee. Average annual water use in the region was reported as high with 36% of available water in the Basin. Water use includes diversion for the major irrigation areas of the Murray Valley, northern Victoria, Sunraysia and the Riverland, as well diversion for large urban centres such as Albury–Wodonga, Yarrawonga, Mildura, Murray Bridge, Adelaide and regional centres in South Australia. The Murray region accounts for 11% of total groundwater use in the Basin, with most use occurring in the central and lower River Murray catchment. Groundwater use represented 5–8% of total water use in the reporting region.
Regulation of water in the catchment
The water resources of the River Murray are regulated from the mountains to the sea, to provide water for hydro-electric power generation, urban centres, irrigated agriculture and the environment, throughout the entire river valley (and beyond).
Irrigation development along the Murray commenced in the 1890s. The River Murray Waters Agreement in 1914, which took 13 years to negotiate, was the first of successive water sharing arrangements between the Basin states – South Australian, Victoria, New South Wales, Queensland and the Australian Capital Territory – and the Commonwealth. The Murray–Darling Basin Authority (MDBA)is the agency responsible for administering current intergovernmental agreements and legislation relating to the River Murray.
Weirs and dams were constructed along the River Murray throughout the 1900s to regulate water flow and service irrigation areas. Torrumbarry Weir (37 gigalitres (GL)) downstream of Echuca was constructed in 1924, Hume Dam near Albury was constructed in 1928 and then expanded in 1961 (3,038 GL), and Yarrawonga Weir (118 GL) was constructed in 1939.
Lake Victoria (677 GL), located 60 km downstream of the confluence of the Murray and Darling rivers, in far-west New South Wales, was constructed in 1925 around natural wetlands. River flows from the central catchment are captured in Lake Victoria to facilitate and regulate flows to South Australia.
The Menindee Lakes storage was constructed on the Darling River in 1968, around ephemeral lakes and associated wetlands, with a capacity of 2,050 GL. Water from Menindee Lakes is used to manage and augment supplies to the lower Murray system.
Dartmouth Dam (3,096 GL) on the Mitta Mitta River was constructed in 1979 to augment water supplies to the Hume Dam and the Murray catchment, and enable further irrigation development.
The Snowy Mountains Hydro-electric Scheme impounded water from several rivers (Snowy, Eucumbene, upper Murrumbidgee and Tooma), which is redirected through tunnels to power generation plants. Water that passes through the Murray power stations via the Geehi Reservoir and Swampy Plain River adds an additional 900 GL of flow to the Murray system. Khancoban Pondage (21 GL), at the end of the Swampy Plain River, stores water from the hydro-electric scheme and subsequently releases it in response to demand for water for irrigation and urban use. Water from the Tooma Reservoir is transferred out of the Murray catchment to the Tumut River, in the Murrumbidgee catchment.
Along the length of the River Murray, water is also pumped directly from the river or diverted through small weirs to secure water for individual properties.
Water management in the Murray catchment is complex and managed by the MDBA. Water is released from Hume Dam, the Menindee Lakes and Lake Victoria to meet daily demand of urban centres (including Adelaide) and irrigators. Water for the lower Murray is preferentially released from the Menindee Lakes and Lake Victoria rather than upstream storages, to minimise river conveyance losses and minimise evaporation losses. Water is preferentially stored in Dartmouth Dam due to its low evaporation losses compared with other storages. Water is transferred from Dartmouth Dam to Hume Dam, as required, to meet forecast demand.
End-of-river flows are captured in Lake Alexandrina and Lake Albert and releases are made to the Southern Ocean via the operation of a series of barrages.
Water delivery for consumptive or environmental use has to take into account a number of constraints in the system. Daily transfer of water from Dartmouth Dam to Hume Dam is limited to around 10 GL per day, flows between Hume Dam and Lake Mulwala is limited to 25 GL per day, and flows downstream of Yarrawonga Weir through the Barmah Choke are limited to 10 GL per day, even with regulators in place, to prevent unseasonal flooding of the Barmah–Millewa Forest. The channel system of Murray Irrigation Limited, in the New South Wales Riverina, may be used to bypass this section of river and augment river flows to meet downstream water demand.
Travel time of water is another important water management consideration. It can take 4 weeks for water to travel between upper catchment storages and the lower Murray. This has a significant influence on system operations, especially when management decisions need to be made well in advance of the range of meteorological forecasts.
Environmental importance
Much of the upper River Murray catchment is undeveloped, preserving large areas of the natural mountain environment. Kosciuszko National Park is recognised nationally and internationally as a UNESCO Biosphere Reserve. The alpine wetlands within the park are of national and international importance. Blue Lake is listed under the Ramsar Convention and all of the alpine fens, bogs and lakes within the park are listed in the directory of important wetlands in Australia.
The Sustainable Rivers Audit 2 (released in 2012) reported that the overall ecosystem health of the upper River Murray valley was poor. Flow regulation had severely affected species abundance and diversity of fish, with the health of the fish community being rated extremely poor. The macroinvertebrate community was rated good condition. Riverine vegetation was rated in moderate condition. The physical form of the river was rated in good condition but elevated sediment loads since European settlement had resulted in sedimentation within the river channel. Flow seasonality and variability were rated good in the mountain zone but poor in the slopes zone, where flows were impacted by water releases from the hydro-electric scheme and supply for urban centres and irrigation.
Water recovery
The Basin Plan specifies how much water is required to satisfactorily manage environmental sites and functions in the Murray–Darling Basin. A sustainable diversion limit (SDL) was established for each catchment (or group of catchments) and the reduction in diversions required to achieve the SDL was identified.
The New South Wales Murray surface water SDL unit applies to the upper and central catchment area on the New South Wales side of the River Murray, from the headwaters of the Murray to its confluence of the Edward River near Swan Hill. For this unit, the baseline diversion level of surface water determined by the Basin Plan is 1,812 GL per year. The required local reduction in take, to achieve an environmentally sustainable level of diversion, is 262 GL per year.
The Victorian Murray surface water SDL unit applies to the upper and central catchment area on the Victorian side of the River Murray, from the headwaters of the Murray to its confluence of the Edward River near Swan Hill, as well as small areas along the Victorian side of the river near Robinvale and Mildura. For this unit, the baseline diversion level of surface water determined by the Basin Plan is 1,707 GL per year. The required local reduction in take, to achieve an environmentally sustainable level of diversion, is 253 GL per year.
In addition to the 'local reduction' for each surface water unit, a further 971 GL per year is to be recovered from all southern Basin catchments (the southern zone 'shared reduction') to meet the needs of the whole Murray system.
Groundwater extractions and/or entitlements determined by the Basin Plan mostly matched the sustainable diversion limits set for the groundwater units in the Murray Alluvium and Goulburn–Murray groundwater water resource plan areas, in New South Wales and Victoria, respectively. Extraction from aquifers in the upper catchment was generally below the sustainable diversion level determined by the Basin Plan. For locally-specific detail of required reductions in water use, water users should consult regional water sharing plans developed by state government water departments.
Further information on water recovery in the Murray–Darling Basin, which includes an interactive map with catchment-specific information, is available at water recovery progress.
The Basin Plan allows for adjustments to SDLs if new works or changes in river operation and management rules increase the quantity of water available to be extracted, or efficiency measures through infrastructure works and upgrades reduce the quantity of water required in a delivery system.
The use of environmental water in a specific catchment or region will vary from year-to-year. The MDBA has produced a Basin-wide environmental watering strategy to guide the use of environmental water across the Murray–Darling Basin to help achieve the best possible results over the long term. Environmental water managers make the day-to-day decisions on what to water and when, in line with the strategy and taking into account seasonal conditions, priorities and the availability of environmental water. Watering decisions are made in consultation with various waterway managers and local landholders.
Catchment or regionally-specific details about environmental water use in the catchment including watering actions, portfolio details and planning, and monitoring of environmental watering, can be found through the Commonwealth Environmental Water Office or the state government environmental water manager (see table below).
Water management
The management of the water resources is the responsibility of local, regional, state and Australian governments.
Delivery to households, industry and farms is managed by local councils or regional water authorities.
State government departments for water ensures the network of authorities manages water responsibly and fairly, that catchment and waterway health is maintained or improved through catchment management authorities, and that water saving, re-use and flood management projects are implemented. State governments must manage their state's water resources according to state and commonwealth water legislation.
In addition to directing operations of the regulated River Murray system, the MDBA implements a number of plans and programs to ensure the waters of the Basin, which flow through 4 states and 1 territory, are managed cohesively and in the best interests of all water users of the Basin. Such programs include:
Useful links
