The need to rescue the Murray-Darling river system has given rise to some fairly outlandish cost estimates, as well as to the usual extremes of overdone pessimism and Panglossian optimism.
I thought of the following as a back-of-the-envelope exercise in cost estimation. Suppose the government bought back 1500GL of water at $40/ML/year, this would be an annual payment of $60 million, which could be financed from a capital sum of $1 billion at 6 per cent interest. I’d guess that increasing natural flows would solve about half the problem, which would imply a total cost of the order of $2 billion. This is incredibly crude, but I’d think the order of magnitude $1 billion – $10 billion is about right, and that we are likely to end up spending something around the low end of this range.
Update: My estimate doesn’t look too bad according to this report
Gary Sauer-Thompson has responded, arguing that the mess we’ve made of the Murray
puts into question the deployment of the modernist conception of the Baconian Enlightenment project by the liberal state to make Australia modern. This use of modernist science (reductionist and elimination of old ideas by new ones) involved an ahistorical, instrumental reason to improve the human condition coupled to an appeal to a tacit notion of progress. It has been thrown into question because its categories got things messed up