Rivers Not Rice

The rice industry is finally looking to head north, and if they stop withdrawing water from the Murray-Darling Basin it would be one of the best things that has happened to the region. One of the things that annoys me most is when someone justifies their actions with "we have been doing it for XXX number of years", and farmers growing water-intensive crops with irrigation from a water-scarce region tend to top the list. The SMH talks about the rice industry ending its "dependence on flooded fields using the increasingly fickle Murray and Murrumbidgee rivers"...I'd use more aggressive language than that, along the lines of "the rice industry could end its gross exploitation of the damaged Murray and Murrumbidgee rivers".

Anyway, on a positive note the northern rice paddies will likely use rain-fed varieties during the monsoon season (as opposed to irrigated varieties in the south). While these produce less tonnage per hectare (Chinese farmers have produced 6-7 tonnes per hectare compared to 10 tonnes in the Riverina) the obvious advantage is that the farms are far less damaging to the natural water system. And it some point the argument against irrigated rice paddies is going to shift from "you shouldn't do that" to "it's really no longer possible for you to do that".

Australia exports 80 percent of its rice, which I suppose is good for the economy but in terms of exporting virtual water is a disaster. There are widely varying reports as to the amount of water required to make a tonne of rice -- this one (http://www.waterfootprint.org/Reports/Report16Vol1.pdf) suggests 3,000 cubic metres while the Australian National Water Commission estimates it's about 1,000 cubic metres in Australia (http://www.nwc.gov.au/resources/documents/DistilledJuly2008.pdf), or about the same as wheat. I don't know how the different numbers were calculated so I'll have to take them on face value. Accepting the Australian figure and using the 80 percent export figure, every tonne of rice produced effectively exports about 800,000 litres of water. Obviously it would be better to get that water from rainfall than from irrigation.

I notice that the National Water Commission has dismissed the idea of using the virtual water to allocate resources because "it can not provide a useful and reliable benchmark for choosing between alternative uses of the nation's scarce water resource". It provides a couple of examples, both which (along with the argument against virtual water calculations) fail because they assume that the proposal is that water allocation be decided solely on the "virtual water" calculation, when the argument is really that the amount of water used to produce something is one of the things that should be taken into account -- and where that water comes from is an integral part of the decision making process.