Perhaps the bigger question is whether Adelaide can support over a million people, particularly considering last week's 46C temperatures. I recall in 'Two Men in a Tinnie' it was thought remarkable that so many people depended on the Mannum pumping station. The Pomanda Weir will be needed to protect that site from saltwater incursion. If the sea level rise at the Murray mouth is around 2 mm a year the lower lakes will eventually be turned to salt anyway. Doing nothing is hardly an option. Since South Australia has perhaps a third of the world's uranium reserves they should combine nuclear power with desalination and then reduce its demands on the Murray.

Interesting point, Taswegian, but the existing barrages will take care of sea level rises and so your point is a red-herring to the real issue which is that agriculture of various kinds is sucking out too much of the river's water. If we banned irrigation of beef and dairy cattle in the basin, for example, and relocated these industries to more appropriate places in Australia this would have a huge effect on the environmental health of the river. If the saved water was shared between environmental and critical human needs (in that order) coupled with storm-water retention, desal etc. then Adelaide's population could grow with attendant benefits to the nation.

What matters most to me is that the building of the weirs will be the beginning of the end for the Murray Darling Basin. The river will become a toxic and dried out mess stage by stage upstream. Maybe when the desertification gets to Canberra they might take their snouts out of their troughs long enough to wonder how they could have been so stupid. How can any politician think that we wont notice that they are killing off the Basin that provides nearly half the food we eat. Agriculture and community depend on healthy river systems to survive. Kill the river off and you kill your community