Mr McEween was speaking in response to yesterday's release of a CSIRO report outlining a future of fewer inflows to the Murray River catchment.

"While South Australian irrigators are the most efficient along the Murray and have been for many years, this report confirms we need to position ourselves to use water smarter and do more with less," Mr McEwen said.

The report is the latest in a series produced through the CSIRO Murray-Darling Basin Sustainable Yields Project and covers the Murray region of southern New South Wales, northern Victoria and south-eastern South Australia.

The project is assessing the potential impacts of climate change and other risks on inflows for each catchment in the Murray-Darling Basin to provide governments with estimates of future water availability.

In comparison to historical climate conditions, the report has found that by 2030:

• Under the best estimate of climate change, surface water availability in the Murray region would be reduced by 12pc and flows to the end of the system by 24pc. SA irrigation would lose 3pc.

• If the dry conditions experienced between 1997 and 2006 continued, average surface water availability would fall by 27pc and end of system flow by 50pc. SA irrigation would lose 12pc.

"The $610 million Murray Futures project, approved at COAG, will enable us to change the way we manage the River Murray system and irrigation industries and be prepared for a drier future," Mr McEwen said.

He said the CSIRO projections must be used in setting new and sustainable limits on how much water can be extracted from the river system.

"As part of the new agreement between all jurisdictions on a national approach to the system’s management, the new Murray-Darling Basin Authority will develop a basin-wide plan that sets new caps on future surface and ground water use," he said.

"This will be vital to address over-allocation in the River Murray system.

"The report also shows that under future climate change scenarios, in extreme droughts the current Murray water sharing arrangements may not give the security we need to meet all of South Australia's critical human needs and water quality requirements.

"This is why the State Government is investing in desalination as a climate-independent source of water that will be an insurance policy against the future climate variability outlined in this report."