09 June, 2009

Irrigation Misunderstandings

Irrigation
Wednesday 18 March, 2009 - 09:50 by David Boyd
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 licenses simply won't fix it!
Take a look at the Murray Darling Basin Authority website and the graph showing 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.
Likewise consider the considerable “cut backs” that have already taken place, from which there has been no discernible benefit. Why? Because there simply hasn’t been any widespread heavy rain in the catchment.
Thus, throwing another $300m at buying back water licenses is really fiddling with the problem and will only restrict much needed production after we have the inevitable big rain event.
The central feature of Australia's inland rivers is their massive variability. Storages can even this out and make production possible and economically and environmentally sustainable.
Under natural conditions the Murray would have stopped flowing 2/3 years ago and salt water would have entered Lakes Alexandrina and Albert (the Lower Lakes), as it always did before The Barrages were built when river flows were low. Yet 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 is more dams and more efficient dams, not less licenses. When the Australian Government recognises this and applies its collective mind to doing something about 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 additional efficient storages, I will believe that they have moved on from shallow, South Australian centric, political games and are actually addressing the real 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 Australia's longterm productive capacity.
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