Draining one seventh (14%) of Australia’s land surface is the Murray-Darling basin, is formed by two major rivers the Murray and the Darling rivers. For most of its length the Murray-Darling traverses low lying land and has a low flow regime. The south eastern rim is the main source of water to the river. Most of the tributaries entering the system are slow flowing, mainly because of the low gradient of the landscape. As the slow flowing river system travels through the arid inland plains, evaporation rates are high adding to water loss and decreased flows. However the system is home to many native species including 16 endangered mammals and over 35 different native fish species.
The river is an important water source for irrigation, industry and domestic users, though 95% of water removal goes to irrigation. Of Australia’s agriculture 40% is contained in this basin, making it Australia’s most important farming region.