The Murray Darling Basin is fed by two rivers, the Murray and the Darling, and their numerous tributaries. It is Australia's most significant river system, and covers 1 061 469 square kilometres, which is about 14% of the Australian continent. This means it is vital to the irrigation of crops, the watering of livestock, and the supply of hundreds of towns' drinking and washing water in four states: Victoria, New South Wales, South Australia and Queensland.
The basin supplies irrigation to around 53% of Australian cereals grown for grain (including 100% of our rice production), 95% of oranges, and 54% of apples; it waters around 28% of Australia's cattle, 45% of sheep, and 62% of pigs; while around 39% of Australia's national income from agricultural production is generated within the Murray-Darling basin.
The wetland areas, of which there are thousands, are significant for their ecological and biological diversity.