Australians have long been captivated by the idea of turning coastal rivers back, to irrigate the dry inland. The most famous advocate of such a scheme was John Bradfield, designer of the Sydney Harbour Bridge.
Such schemes have always foundered on the ugly physical fact that water is heavy. Any significant amount of uphill pumping is prohibitively costly, so schemes of this kind require lots of expensive tunnelling, and can only get access to water from the upper slopes of the Great Dividing Range.
As coastal populations have grown, we’ve seen increasing interest in the reverse option, of taking inland water to the coast. Adelaide is already buying water back from irrigators on the Murray. Current Victorian policy prohibits Melbourne from doing the same, but it’s hard to see this ban being sustained as water restrictions are tightened, and the technical difficulties are not great.
Today’s Australian has a proposal from Dennis O’Neill of the Australian Council for Infrastructure Development to take water from the Tantangara Dam on the Snowy to Sydney, via Googong dam near Canberra. This sounds a lot more expensive than the options for Melbourne and Adelaide, though not in the same league as Colin’s canal. And at least the scheme works with gravity rather than against it. I’ll look forward to seeing a more detailed proposal.
All of this will certainly make for interesting times for irrigators on the Murray-Darling, the main focus of my research and modelling. On the one hand, those who are able to sell water rights stand to do very well. On the other hand, those wanting to buy will be competing with the swimming pools and gardens of the big cities (the uses currently subject to the tightest restrictions).