Ian Edmonds has come up with a plan to use the powerful current to float massive sacks of fresh water 1600 kilometres south along the Queensland coast, from the Tully River south of Cairns to Tugun at the Gold Coast. The journey would take about 20 days and each membrane would need towing into shore before being emptied into the Southern Regional Water Pipeline for pumping around South-East Queensland.

The 60 million litre reinforced plastic membranes would be roughly the size of the infamous Pasha Bulker bulk carrier. However, instead of sitting above the water, the sacks would be almost completely submerged. "What you're doing with the bags is you're simply enclosing the water, not supporting the water and because the density of fresh water is slightly less than the density of sea water, the entire bulk of the thing is 97 per cent submerged with only three per cent sitting above the water," Dr Edmonds says.

He believes this would leave the membrane unaffected by wind and safe to stay with the current. Each vessel would cost $600,000 and the total cost of the proposal would come close to $30 million.

Dr Edmonds said that made more financial sense than the multi-billion dollar cost of a plan to build a pipeline from the Burdekin River in North Queensland to Brisbane, or expensive desalination plants. "The running cost of this scheme is low as the water used is pristine river water. (It) is transported the 1600km by the East Australian Current for essentially no cost with only 90km towing distance for transport between the current and the coast," he says. CSIRO research scientist David Griffin says the idea has merit, but needs tweaking.

"This is just a more sophisticated use of ocean currents," Dr Griffin says.

"You're using (the current) as a motive power but you can't just go in the direction of slavishly going with it, which just means a little bit of application of some sort of power at critical points." The EAC is the largest ocean current close to any coast of Australia.

From its source in the Coral Sea, it moves masses of tropical water south down the Australian coastline to the temperate regions, with ocean eddies peeling off into the Tasman Sea along the way.

However, winds within 10 nautical miles of the shore can slow down and even reverse the current and Dr Griffin believes that makes some sort of small propulsion power necessary. "You need the little bit of intelligent intervention at strategic times to make sure the bag gets from A to B," he says. University of Queensland civil engineering expert Tom Baldock also agreed Dr Edmonds' idea was feasible.

"The variability of the current might need to be taken into account but it certainly runs down this far and it makes sense to use the current," Dr Baldock says. "The key thing is keeping track of them and making sure if something happens they can be recovered."

Dr Edmonds concedes there is some potential for a stream of submerged membranes to become a shipping hazard, but believes fitting them with light and radio beacons would make them traceable to within a few metres.

Dr Griffin also raises environmental concerns about "masses of plastics sloshing around" on the Great Barrier Reef should a membrane float off course and shag on the coral. "The bags would have to be fairly strong and that would break reefs and no one would allow that to happen." Dr Edmonds acknowledges the potential hazard but says a large sheet of plastic is much easier to retrieve from a reef than an oil tanker.

"In the case of the Pasha Bulker, for example, you've got a real problem there because you end up with a very big steel vessel sitting on the reef and there's nothing you can do about it. "But if you've got a membrane that weighs 20 tonnes then that's easy to retrieve."

Dr Edmonds says he sent the proposal to a number of state government departments over the last couple of days and was eagerly awaiting their feedback. "You've got to weigh up the situation; if you really want to use river water you've got to use it somehow." He also believes his Northern Rivers plan is a wise alternative over the long term.

"Given the fact that the drying trend in South-East Australia is related to climate change, the use of high-emission desalination plants would seem to be very counterproductive. "The technology of this proposal could be readily exported to anywhere in the world where there is a need for fresh water and there is a favourable ocean current connecting to a river supply, however distant that supply may be."