I stayed in a house by the Murray River just upstream from Barham in the Central Murray Valley in November 2007. Every morning I drank a large glass of water from the kitchen tap; water that had been pumped straight from the river. The water tasted fine, and I didn’t get sick.
In the afternoon, I sometimes swam in the river. It was deep and there was often a strong current because water was being released from Hume Dam.
The bird life was especially amazing, with wood ducks on the river, cockatoos and galahs on the lawn, superb blue wrens amongst the roses and red-rumped grass parrots in the red gums.
According to Penny Wong, then Minister for Climate Change and Water, the two-year period to November 2007 recorded the lowest ever inflow to the Murray River. Inflows during that period were 43 percent lower than previous record lows which occurred at the end of 1938.
Given at the height of the drought there was water in the Murray river, and that it was of such a high quality that I could drink it, a reasonable person might conclude that all things considered the Murray River was okay – even healthy.
But for the computer modelers at the Murray Darling Basin Authority (MDBA), it wouldn’t have mattered if I had died of dysentery drinking that water. Their only concern – the only concern of the models currently underpinning the new water plan, also known as the guide – is how much water goes down the river.
And while the bureaucrats claim the new guide is not about returning rivers to their natural state, in fact these models average and then compare quantities relative to a hypothetic pristine condition again defined solely in terms of amount of water. Any reduction in the amount of water is considered bad, so irrigation is automatically bad.
Some old-timers complain about the quality of the water in the rivers and streams of the Murray Darling Basin because they remember it before the carp.
This introduced fish has muddied the waters.
But the computer models don’t consider carp, or the resulting turbidity, and so this pest is irrelevant to the new guide.
As the newly-appointed head of the MDBA, Craig Knowles inherits the computer models.
And as the new boss, he ought to come to terms with how they work because they underpin the planning process which is unreasonable and illogical.
I suggest Mr Knowles begin by reading an important book by Aynsley Kellow, head of the School of Government, University of Tasmania, titled ‘Science and Public Policy: The Virtuous Corruption of Virtual Environmental Science’ (Edward Elgar, 2007).
It explains the history and limitation of the type of computer modeling that is currently obsessing the MDBA technicians.
Professor Kellow explains, in particular, the dangers of developing public policy on the basis of these tools.
Mr Knowles would do well to heed this advice and consider a planning process that incorporated not only the impact of carp, but may other aspects of the river’s ecology.
First published in The Land newspaper on February 3, 2011, page 31, under the title ‘Knowles needs to know models’