Solving South Australia's Water Shortage with Plastic Bladders?
As far as unconventional ideas to resolve droughts go, this one by Queensland physicist Ian Edmonds is a winner. What he suggests doing is float large volumes of fresh water in plastic "bladders" down the East Australian current from the north of Australia (where water is plentiful) to the south, a scheme he argues would be much cheaper and more eco-friendly than relying on pipelines or desalination plants.
The fresh water would come primarily from northern rivers like the Tully River and be wrapped in large membrane-like "bladders," or bags, before being towed 90 km off shore and left to ride the current, which reaches speeds of up to 6 km per hour, down the Australian east coast. The costs would be minimal: the bags, made from 1 mm thick fabric reinforced plastic, and the tugs to tow them. According to his calculations, they would be roughly 30 times less than the costs to build an equivalent desalination plant (around $3-4 million).
"I think it's always good to look at new options, and it does at first count, of course, using the sea, the buoyancy of the sea to transfer water and therefore save energy in that transport is good idea, sending water long-distance by pipeline or worse, in an emergency trucking, that is, a very energy-intensive and very expensive business and this could actually have some cost advantages over that. The real question is whether it's needed and whether it's very sensitive to the operating costs and capital costs and could actually be more expensive than being suggested," said Stuart White, Director of the Institute for Sustainable Futures, who deemed the proposal promising.
Other scientists, including Martina Doblin of the Institute for Water and the Environment and David Griffin of the Commonwealth Scientific and Industrial Research Organization (CSIRO), have expressed reservations about the plan, citing concerns that the bladders could burst or get stranded along the way on the Great Barrier Reef. Edmonds, who concedes these points, still believes his scheme is valid and plans on applying for support from the Queensland government.
As far-fetched as it may sound, it would be great to see this type of DIY, out-of-the-box project succeed where many others have failed (green schemes don't have to be expensive or overwrought). While it remains to be seen whether it can work given all the countervailing factors, we'll be eager to see what the outcome is.