Saturday 30 May, 2009 – 07:25 by David Boyd in Irrigation
Solution flows from fewer licences and more dams
May 30, 2009
There seems to be a fundamental misunderstanding of the cause of our record low river flows, particularly in the Murray-Darling, and buying back water licences won’t fix it (“River rescue deal leaves NSW spluttering”, May 29).
Take a look at the graph on the Murray Darling Basin Authority website that shows record low run-off into the Murray in recent years. The problem is clearly not extractions, which in any event are limited by low, or no, allocations. The problem is lack of run-off and too few efficient water storages.
There has been no discernible benefit from the water licence purchases and lower allocations that have taken place. Why? Because there has been no widespread heavy rain in the catchment. Thus, throwing another $300 million at buying back water licences is fiddling with the problem and will only restrict production when the rain does come.
The central feature of Australia’s inland rivers is their massive variability. Storages can even this out and make production not only possible, but economically and environmentally sustainable.
Under natural conditions the Murray would have stopped flowing about two years ago and salt water would have entered Lakes Alexandrina and Albert (the Lower Lakes), as it always did when river flows were low before the building of barrages. Yet in this drought, with some water available from Eildon, Hume and Dartmouth dams, and from the Snowy system, a flow in the Murray has been maintained.
Conclusion: what we need are more dams and more efficient dams, not fewer licences. The Federal Government needs to recognise this and apply its collective mind to the profligate waste of fresh water in the form of evaporation from the man-engineered Lower Lakes and Menindee Lakes, and to identifying new sites for efficient storages. When it does so I will believe that it has
moved on from shallow, South Australia-centric political games and is addressing the problem.
With increasing world food shortages, Australia has a moral duty to maximise production, providing this can be done, as it can, without damage to our long-term productive capacity.
David Boyd St Ives