How to save the Coorong
On this blog, there have been a number of posts about the plight of the Coorong, a terminal estuarine system at the end of the Murray River along the coast of South Australia.
In July 2007, I posted a link to presentations by Professor David Paton at the University of Adelaide on the “Death of the Coorong“. David Paton, the leading expert on the Coorong, described the horrible decline of birds, plants, fish and invertebrates in the Coorong system, as a result of years of man-made and natural drought conditions. It should be noted that 90% of waterbirds in the Murray Darling Basin used to live in the Lower Lakes and Coorong. David Paton said the result of continued inaction is likely to be the extinction of some species in the Coorong, and perhaps the compete extinction of the Fairy Tern globally. His student, Dan Rogers presented research on waterbirds in the Coorong in November 2007. Dan argued for an integrated management system to support policy decisions on managing the Coorong.
In May 2008, I pointed to a series of videos available for download from Catalyst describing the problems of acid sulphate soils and low flows in the Coorong and Lower Lakes. In one of the videos, Mike Young from the University of Adelaide, proposes a different water sharing model for the River Murray that would give the environment a larger share of the water in the system at low flows. In March 2008, I had interviewed Mike Young on the challenges facing the River Murray system and he proposed two key steps to create a “Future-proofed Murray Darling Basin“
1. Replace the current entitlement and allocation regime with a robust one that can be confidently explained as one that will work no matter what the climate scenarios in the future
2. Implement the resultant change in a just a fair manner.
This has not happened yet, and given the pace of reform nationally, is unlikely to happen for some time yet, if at all. This is a complex problem, and it is difficult to trade off the needs of different users of water in the River system, especially when you are not always sure who really needs what water and when.
In a piece of positive news, a recent study by scientists on the Coorong have identified an important number – 300GL. This is the amount of water that needs to flow out at the end of the Murray River to maintain the health of the River. This number is based on an impressive, interdisciplinary and integrated research program called CLLAMMecology, but it gives a simple piece of advice to government. You need 300GL of water flowing out the bottom of the River to maintain the health of the Coorong. The Coorong is a Ramsar wetland, and government has a responsibility to the global community to protect this habitat which supports bird populations that migrate to countries across the northern hemisphere. I suspect 300GL of water out of the bottom of the system will deliver a whole range of other environmental benefits upstream as well. 300GL would be 2% of diversions in an ‘average’ year, and 5% of diversions in years more typical of the last five. Setting such a target would meet Mike Young’s principle of “entitlement and allocation regime…that can be confidently explained ….that will work no matter what the climate scenarios in the future “.
You can download podcasts and videos from the CLLAMMecology study presentations here.
You can register for the Litfuse feed on your i-tunes or mp3 player: http://feeds.litfuse.com.au/litfuse
Written by Paul Dalby on 22 July 2009
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