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CANBERRA - The mighty Murray River, the lifeblood of eastern Australia, is facing a crisis that will continue to deepen even after new emergency measures to keep it alive through the drought are implemented.
The river has been groaning for years under massive demand that has dramatically reduced its flow, led to the closure of its mouth in South Australia, and added to salinity that has killed hundreds of thousands of hectares of farmland along its 2500km course.
Relentless and severe drought in New South Wales, Victoria and South Australia has created new urgencies: last year inflows into the river plunged 60 per cent below the previous record lows.
If the drought does not end this year, or if inflows trickle into the lowest one per cent of years on record, major cities and towns will face critical water shortages.
Key among these are Adelaide - whose one million people take 90 per cent of their water from the Murray - and large regional centres such as Swan Hill, Mildura and Echuca in Victoria, and the twin New South Wales-Victoria border cities of Albury and Wodonga. As many as 2.5 million people could be affected.
So far authorities believe the worst can be avoided and that there will be enough water for the time being but say contingency measures are needed.
Researchers warn climate change will create long-term problems as snow vanishes from the Snowy Mountains and bushfires ravage more alpine forests.
Professor Mark Adams, of the University of New South Wales Laboratory for Ecosystem Science and Sustainability, said Australia's high country was crucial.
Water and hydro-electricity generated there fed cities, agriculture and much of Australia's economy. But new studies predict that almost no snow will fall on the Snowy Mountains by 2050, eliminating a major flow to the river system. Adams also said that more frequent and severe bushfires will further hit the Murray.
"Unchecked bushfires create large-scale forest regeneration that uses more water than the mature forests they replace," he said. "Research shows that the 2003 fires, for example, will likely reduce flows by more than 20 per cent for the next 20 years in the Kiewa River, a major tributary of the Murray."
A new A$1.7 million ($1.9 million) research project has been launched to study the interaction between water, soils, trees and fires in the high country.
In the meantime, the federal, NSW, Victorian and South Australian governments have agreed on radical measures to tackle the drought crisis now facing the Murray and the possibility that this will be another dry year.
Following a summit last November, senior officials drew up an emergency plan that includes tough new town water restrictions, lower end-of-season reserves in NSW's Lake Victoria, reduced minimum flow targets and early pumping to boost reserves in South Australia's Mt Loftystorages.
