Sharing River Murray Water
The water in the River Murray is shared between three states - Victoria, New South Wales and South Australia under the Murray-Darling Basin Agreement. All of the River Murray system inflows and the storage capacities are apportioned between these states. Victoria has one half share of River Murray flows above Albury, plus all of the Victorian tributary inflows below Albury into the River Murray, plus a share of Darling River flows. Victoria can also store these inflows in Victoria's "half" of Dartmouth Dam, Hume Dam, Lake Victoria and the Menindee Lakes. From these flows, Victoria must provide half of South Australia's water requirements.
The Murray-Darling Basin Commission keeps a complicated set of water accounts which define the water resources available to each state at any point in time and how much they have used.
The application of these continuous water accounting rules allows Victoria to hold water it wishes to save from one season to the next. These accounting rules effectively isolate Victoria's water resources from New South Wales' water allocation practices.
Within Victoria's share of Murray Darling Basin water resources, Goulburn-Murray Water uses the seasonal allocation rules detailed elsewhere.
As Victoria shares water in storages and inflows spread from the Snowy Mountains to the South Australian border including the Darling River catchment, rain far away can influence the availability of water for Victorian users. For example, floods in southern Queensland in January 1995 provided significant flows in the Darling River which were used to meet South Australia's water requirements. This freed up water in Hume and Dartmouth for use in Victoria and led to an increased seasonal allocation for Victorian River Murray water users.
