Large plastic membranes shaped like submarine hulls are being proposed as a way of alleviating Australia's crippling drought.
Brisbane physicist Ian Edmonds, who runs a building industry research and development company, proposes using the east Australia ocean current, which sweeps down the coast of Queensland, to float 15.6 million-gallon polyurethane membranes filled with water from north to south Queensland.
The membranes would travel almost 100 miles south from the Tully River, near Cairns, where fresh water is abundant, to the Gold Coast. Edmonds said the membranes would take about 20 days to drift on the current. At the Gold Coast, they would be corralled, towed ashore and emptied into the southeast Queensland regional water supply.
Edmonds said each membrane would be the size of a medium bulk freighter and would be unaffected by wind on its journey south. Because fresh water is less dense than seawater, Edmonds said 97 percent of the membrane would sit below the surface. They would be fitted with lights and radio beacons to warn ships.
Edmonds has asked Gold Coast-based Fabric Solutions Australia Pty. Ltd. if it can manufacture the giant membranes. Chief Executive Officer Peter Ives said, ``Of course,'' but there will be ``some engineering challenges.''
Fabric Solutions currently manufactures a range of flexible tanks, using material reinforced with PU. The company is under contract to provide large water bladders for the Australian Defense Force and fuel bladders to remote mining sites in Australia and Indonesia.
Fabric Solutions's material is a U.S.-military-specification PU that Ives said has ``great inherent strength.''
``Even though all our bladders and membranes are currently for static use only, with a marine engineer, we can build whatever Dr. Edmonds needs.''
Edmonds said he believes each membrane will cost A$600,000 (US$494,000), with the total cost around A$30 million (US$25 million) for 40 membranes plus towing costs to and from ocean currents. That makes more sense, he said, than installing pipelines from north Queensland to Brisbane or building expensive desalination plants.
``The technology of this plan can be easily exported anywhere in the world where there is a need for fresh water and a favorable ocean current.''
Edmonds has written a comprehensive paper outlining his proposal and the funds required to make it reality. The scientific community generally has backed the idea. University of Queensland civil engineer Tom Baldock said floating the membranes down the coast is ``feasible,'' but the key will be ``keeping track of them in case something happens.''
Australia is in the grip of the worst drought in 20 years, with most dams in southeast Queensland at their lowest levels ever. Severe restrictions are in place in much of Queensland.