Murray-Darling Plan 2012 includes regaining 450GL a year for South Australia's Coorong and lakes at river mouth

The Coorong and lower lakes at the mouth of the River Murray are threatened with salinity without a proper river inflow.
Image courtesy South Australian government environment and water department

The historic Murray-Darling Basin Plan of 2012 – signed off after long and painful negotiation by South Australia, Victoria, New South Wales and Queensland and the Australian Capital Territory – included 450 gigalitres (GL) to be recovered from the rivers systems for the ultimate benefit of the Coorong and lower lakes in South Australia.

The 450GL was sought by South Australia to keep the River Murray mouth open, to reduce salinity in the Coorong and lower lakes, and to increase flows to the Coorong. The Coorong has special importance as a Ramsar site: wetlands of international importance according to a convention signed in the Iranian city of Ramsar in 1971.

In 2007, in response to drought and concerns about “shortcomings of the current model”, the federal government sought, and eventually gained, powers to oversee the managing of water in the Murray-Darling Basin.

The Murray-Darling Basin Plan of 2012 was hailed as an historic bipartisan agreement about how to use the water that flows down the nation's longest river system. It aimed to recover the equivalent of 2750GL of water a year by 2019 and an additional 450GL each year (for South Australia’s Coorong and lower lakes) by 2024, to restore the health of the rivers, through water efficiency and the cutting the amount used by irrigators.

Although the Murray-Darling Basin Plan was signed into law by prime minister Julia Gillard in 2012, the plan remained highly controversial. Some argued it didn't go far enough in favour of the environment and won't return the rivers to health. Others said it went too far, causing irreparable damage to irrigation-dependent communities and agricultural production.

The Murray-Darling Basin drains one-seventh of the Australian continent and represents one-third of its agricultural production. It is home to more than two million people and 16 Ramsar-listed wetlands.

The Murray-Darling Basin Plan included an “adjustment mechanism” to change the water recovery target but it left it to future governments to work out how, or if, that should happen.