| Ord River | |
|---|---|
Ord River from a boat |
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| Origin | Kimberley Plateau |
| Mouth | Cambridge Gulf, Timor Sea |
| Basin countries | Australia |
| Length | 650 km (400 mi) |
| Source elevation | 531 metres (1,742 ft)[1] |
| Mouth elevation | sea level |
| Avg. discharge | 3,870,000 ML/year[2] |
| Basin area | 46,100 square kilometres (17,799 sq mi)[3] |
The Ord River is a 320-kilometre-long river in the Kimberley region of Western Australia. It was named in honour of Harry Ord, Governor of Western Australia from 1877 to 1880.
The headwaters of the Ord river are located below the 983-metre Mount Wells and initially flows east and around the edge of Purnululu National Park before heading North through Lake Argyle then passing west of Kununurra and discharging into the Indian Ocean in Cambridge Gulf. The river has 35 tributaries of which the five longest are Bow River, Nicholson River, Dunham River, Panton River and Negri Rivers.
The lower reaches of the river support an important wetland area known as the Ord River Floodplain, a protected area which contains numerous mangrove forests, lagoons, creeks, flats and extensive floodplains.[4]
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The Ord River Irrigation Scheme (ORIS) was constructed on the river in 1963 and opened on 30 June 1972 by Prime Minister William McMahon. Allocation of farming land during Stage 1 of the project was completed in 1966.[5] 30 farms produced mostly cotton, however pest problems soon became apparent. The early 1970s saw the application of large amounts of pesticides on crops. The primary pest was the caterpillar Helicoverpa armigera which developed resistance to the pesticides. The resulting low crop yields combined with a drop in world cotton prices led to suspension of the commercial cotton industry in the region.[5]
The scheme created Lake Argyle, which is Australia's largest dam, covering an area of 741 km².[6] Lake Kununurra was also constructed as part of the project. Associated wetland areas have been preserved within the Lakes Argyle and Kununurra Ramsar Site.
ORIS provides water for irrigation to over 117 km² of farmland and there are plans to extend the scheme to allow irrigation of 440 km² in the near future. The dam also generates power for the local community of Kununurra. By 2009 more than 60 different crops were grown in the Ord catchment area.[7] One third of the area is used for sugar cane cultivation.[8]
The Ord River Dam Hydro Scheme is a privately funded, owned and operated power system in the East Kimberley region of Western Australia. It consists of a new 36 MW hydro electric power station at Lake Argyle interconnected, by lengthy 132 kV transmission lines, with existing diesel fuelled power systems at the Argyle diamond mine and the Kununurra township. The scheme can currently only produce 1% of the power the Snowy Mountains Scheme produces. The power station was constructed from 1995 to 1996.[8]
CSIRO research conducted in 2008 found that the water quality in the lower reaches of the river was good and that planned activities were not an ecological threat.[9] Salinity and erosion are also becoming an issue in the area, due to the rising of the water table in the area. The use of groundwater drains has been suggested by hydrologist Dr Tony Smith, as a possible remedy to salinity problems.[9]
Some concerns have been raised that the large body of water created by the dam could attract Asian insects and birds which may transmit dangerous viruses such as avian influenza.[5]
Like so many other experiments in tropical agriculture the scheme initially failed because of difficulties growing crops and attack from pests. Today the irrigated areas successfully produce a variety of fruits and vegetables, with the most successful being sandalwood.
The site forms part of the Ord Irrigation Area Important Bird Area (IBA), so identified by BirdLife International because of its importance for wild birds, especially estrildid finches.[10]
Much of the produce is exported to South East Asia.[5] Sugar from the ORIS is trucked to Wyndham where it is exported to a Korean-owned food manufacturing plant in Surabaya, Indonesia. Fruit and vegetables are sold to domestic markets and are trucked to all capital cities. The ORIS is also home to the largest commercial Indian Sandalwood plantations in the world.