The Murrumbidgee River is the third longest river in Australia. The Murrumbidgee River catchment, located in New South Wales and the Australian Capital Territory, is diverse and complex.
The Murrumbidgee catchment is home to many wetlands and riverine environments, including the Lowbidgee wetlands and Tuckerbill and Fivebough swamps. The river starts in the Australian Alps and completes its journey on the semi-arid riverine plains.
Almost one-third of the Basin's population live in the Murrumbidgee catchment. A quarter of New South Wales' fruit and vegetable production, 42% of the New South Wales grape production and 50% of Australia's rice production comes from this region.
The Murrumbidgee’s largest tributary, the Tumut River, houses part of the Snowy Mountains Hydro-electric Scheme, and Canberra is in the upper catchment.
Snapshot
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Catchment area
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8% of the Murray–Darling Basin
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Contribution to Basin water
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16%
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Annual stream flow
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4,000 GL per year (Wagga Wagga)
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River length
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1,485 km
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Tributaries
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Cotter, Yass, Tumut
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Towns include
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Cooma, Canberra, Yass, Tumut, Gundagai, Cootamundra, Wagga Wagga, Narrandera, Leeton, Griffith, Hay and Queanbeyan
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Water storages
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Burrinjuck (1,026 GL), Blowering (1,628 GL), Talbingo (921 GL), Tantangara (254 GL), Googong (125 GL)
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Key water users
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Irrigated agriculture, hydro-electricity, urban water supply
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The landscape and its water
From its source high in the Australian Alps, the Murrumbidgee River winds through the alpine regions of Kosciuszko National Park and the Monaro High Plains, and then through the Australian Capital Territory. Once the river reaches the south-west slopes of New South Wales, it heads west across the riverine plains to its confluence with the River Murray near Balranald. The Tumut River is the largest tributary of the Murrumbidgee, and it also has its headwaters in the Australian Alps.
Annual average rainfall in the catchment ranges from over 1,600 mm in the cool temperate alpine regions, at an elevation up to 1,400 m, to around 350 mm on the semi-arid plains of western New South Wales, where the elevation is less than 100 m. Most of the inflow of the catchment occurs in the Great Dividing Range. Snow melt in the mountains contributes to water supply in the catchment.
Surface water and groundwater systems in the catchment range from being highly connected to permanently disconnected. The interaction between the sources is influenced by extraction of surface and groundwater use, seasonal conditions and frequency, significance and duration of floods. Most upland streams receive flow from fractured rock aquifers.
People, industry and water use
The largest Aboriginal nation on the slopes and plains of the Murrumbidgee catchment are the Wiradjuri, whose nation extends from the River Murray to beyond Dubbo in the north, and west to Balranald. In addition to the Wiradjuri, there are several smaller nations at the western end of the catchment, including the Barapa Barapa, Muthi Muthi, Nari Nari, Nyeri Nyeri, Wadi Wadi, Wamba Wamba, Weki Weki, and Wolgalu. The mountains at the eastern end of the Murrumbidgee catchment are the country of the Ngunawal and Ngarigo nations.
European graziers established pastoral runs in the Murrumbidgee catchment area in the 1820s, initially farming cattle, then sheep and later growing grain crops. The introduction of river steamboats encouraged trade of timber, wool and other goods from the 1860s until the early 20th century. The Murrumbidgee Irrigation Area was established in 1912, and the production of a wide range of horticultural crops commenced; with further development of the area and the construction of more dams in the upper catchment, rice production established in the 1920s.
The population of the Murrumbidgee catchment is about 550,000. The Australian capital city of Canberra, located in the east of the catchment, has a population of around 462,000. Across the border, Queanbeyan has a population of nearly 40,000. Wagga Wagga in the centre of the catchment is the largest inland city of New South Wales, with a population of 69,000. Other major centres include Cooma (7,000) in the upper catchment, and Griffith (27,000) and Leeton (11,000) in the lower catchment.
Land use in the Murrumbidgee Valley is diverse, reflecting the differences in geography and climate across the region. About 85% of the region is private land. Dryland grazing and cereal-based cropping account for more than 75% of land use and 5% is irrigated. Commercial forestry occupies about 3% of the catchment, mainly in the east. Tourism is also an important industry for the region. The region generates about 37% of all renewable energy produced in eastern Australia, through the Snowy Mountains Hydro-electric Scheme.
The Commonwealth Scientific and Industrial Research Organisation (CSIRO) reports that 53% of available surface water (including transfers from the Snowy Mountains Hydro-electric Scheme) is extracted for use, which is very high compared with other catchments in the Basin. Groundwater extraction is 17% of available resources, mainly in the mid to lower catchment.
Regulation of water in the catchment
Settlement along the Murrumbidgee River began in the 1820s but efforts to establish farms on the floodplains were thwarted by the cycles of drought and flood. Preliminary efforts to irrigate commenced at Yanco. As a result of a Royal Commission in the 1880s, the establishment of the Murrumbidgee Irrigation Area (MIA) commenced in 1903 with the construction of canals west of Narrandera and construction of Burrinjuck Dam in 1906. Subsequent expansion of Burrinjuck led to expansion of the MIA and the capacity to generate hydro-electricity.
The construction of Blowering Dam on the Tumut River, as part of the Snowy Mountains Hydro-Electric Scheme, made more water available for irrigation and the Coleambally Irrigation Area was established. The Berembed, Yanco and Gogeldrie weirs were constructed to control water flow from the Murrumbidgee River into the Murrumbidgee and Coleambally irrigation areas.
The Snowy Mountains Hydro-Electric Scheme impounded water from several rivers (Snowy, Eucumbene, upper Murrumbidgee and Tooma) and redirects it through tunnels (and power generation plants) to the Tumut River, and then the Murrumbidgee. Water management within the Murrumbidgee catchment is quite complex due to its interaction with the Murray and Snowy river systems.
Environmental importance
The Murrumbidgee River is an important water source for many wetlands, including Fivebough and Tuckerbill swamps near Leeton, and 16 wetlands listed as nationally significant in the directory of important wetlands.
The Lowbidgee floodplain is the largest wetland remaining in the Murrumbidgee Valley. Located between Maude and Balranald, the floodplain covers an area of over 2,000 km². It includes the 2nd largest red gum forest in Australia (along the river downstream of Redbank Weir) and significant black box, lignum and reed-bed communities. The wetlands support large numbers of waterbirds, many of which breed in the extensive lignum swamps, and provide habitat for many threatened species.
The mid-Murrumbidgee wetland is a network of riverine lagoons and billabong formations that occur along the river between Narrandera and Carrathool. These wetlands rarely dry out completely and provide drought refuge for a wide range of species including many listed as endangered or threatened. Fivebough Swamp is a permanent fresh to brackish, shallow wetland and Tuckerbil Swamp is a seasonal, shallow, brackish to saline wetland. Both wetlands are important waterbird habitat, provide refuge within the surrounding agricultural landscapes and are Ramsar-listed.
The Sustainable Rivers Audit reported overall ecosystem health of the Murrumbidgee River valley was poor. Flow regulation had severely impacted the abundance and diversity of fish, with the health of the fish community being rated very poor. The macroinvertebrate community was rated in moderate condition, with the greatest impact on the lowland zone of the valley. Riverine vegetation was rated in moderate condition in the valley overall, however condition was good in the lowlands and the montane zones. The physical form of the river was rated in good condition but elevated sediment loads since European settlement has resulted in sedimentation within the river channel and floodplains of the Lowland and Slopes zones. Flow seasonality and variability was rated poor in the valley, especially in the lowland where flows are impacted by the seasonal supply of water for irrigation.
Water recovery
The Basin Plan sets Sustainable Diversion Limits, which is how much water can be used in the Murray–Darling Basin, while leaving enough water for the environment. 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 use of environmental water in a specific catchment or region will vary from year-to-year. The Murray–Darling Basin Authority (MDBA) has 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 Holder or the state government environmental water manager.
More information
Water management
The management of 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 ensure 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.
Rural water authority
Urban water authority
Catchment management authority
State government water
Use of environmental water
Irrigation water allocation
Maps
