On Saturday I debated Arelene Harriss-Buchan, from the Australian Conservation Foundation, on the subject of ‘Water usage in the Murray-Darling Basin’ at the AUSVEG 2011 National Convention and Trade Show in Brisbane. Following are the notes I used in opening…
THIS morning I want to talk about the single largest user of water in the Murray Darling Basin – the Lower Lakes.
When six concrete barrages spanning 7.6 kilometres were completed in 1940, blocking inflows from the Southern Ocean, the lakes became an artificial freshwater system. The barrages were built during the depression, generating employment and to stabilize water levels in Lake Alexandrina, and they destroyed a once thriving River Murray estuary.
Today, the Lower Lakes are Ramsar listed, meaning they are considered an environment of international environmental significance, and there is a campaign to increase their annual water allocation by four million megalitres per year. But it is all so unsustainable in this land of drought or flooding rains.
Arlene Harriss-Buchan, representing the Australian Conservation Foundation, is on the public record campaigning against irrigated agriculture in particular claiming that over-allocation has ruined the Murray River system. But after at least 15 years of water reform I believe we have finally got the balance right between environment, communities and agriculture – where it not for the barrages.
I say this because during the recent protracted drought the river did not run dry as it has during previous droughts. There was enough water in upstream storages to supply Adelaide. The quality of the water was good; it was not salty.
There was even enough water for the world’s largest ever environmental watering with 515 Gl flooding the Barmah-Millewa forest in October 2005. There was not enough water to grow rice, but we don’t expect to grow rice during drought.
One environment, however, did suffer terribly and its suffering had nothing to do with Australian agriculture. The Lower Lakes were allowed to dry-up and it was so unnecessary. The lakes could have filled with seawater as once happened naturally. But instead the barrages were slammed shut keeping out the Southern Ocean.
Once upon a time each spring, after good winter rain and snow melt, the Murray would tumble down from the Mountains spread over the vast Riverina, wind its way through the limestone canyons of the Riverland, before flooding into Lake Alexandrina. But often by New Year, the river exhausted, and a breeze picking up from the southwest, the Southern Ocean would pour in through the Mouth. With the seawater came vast schools of Mulloway.
The fish came each autumn to spawn.
The sea would work its way up across the lake and sometime into the river. And so the lakes would be sometimes fresh and sometimes salty, but always full of water and each autumn full of Mulloway.
Then the massive steel and concrete barrages were built.
In the autumn of 1940, the year the barrages were completed and sealed, the Mulloway entered the Mouth, passed along the Goolwa channel and died in their hundreds of millions entrapped by the barrages and the falling tide.
The barrages killed the Mulloway fishery and crippled the estuary.
Visit the pub in Milang today – the little town that used to be home to a thriving Mulloway fishery – look at the menu and there is no Mulloway. Instead there is barramundi from Queensland, because the lakes are now full of the pest, European Carp.
The barrages created an artificial freshwater lake system, and there are now demands for an extra 4 million megalitres per year of freshwater to maintain this large, artificial oasis in the driest state on the driest inhabited continent.
Visit the new marina at Hindmarsh Island, the new housing estates, go water skiing at Milang and you soon realize there is not very much natural environment left.
The Lower Lakes are Ramsar listed, but they are neither natural, nor healthy.
For many South Australians the water allocation is about maintaining a lifestyle, for the Australian Conservation Foundation the Murray’s mouth has been a symbol for a long-running campaign against irrigated agriculture.
What upstream irrigators need to realize is, that like it or not, the Water Act 2007 puts environment first: the Lower Lakes before agriculture. To quote Sydney Barrister Josephine Kelly “The Water Act puts the environment first when allocating water in the Murray-Darling Basin. Social and economic considerations are not relevant to deciding how much water the environment needs. Water available for human use is what is left.”
This system of prioritising is reflected in the New Guide with the largest single water allocation destined for the Lower Lakes.
The lakes did not need to dry out during the recent drought. That they were allowed to is a sad indictment of Australian politics. The barrages could have been opened. But the South Australian government choose to keep them slammed shut.
The problem for the Murray, for its estuary is not agriculture. It is politics and the barrages. During the prolonged recent drought the South Australian government sacrificed the lakes to make a political point.
And during the recent drought, the Australian Conservation Foundation could have campaigned to have the barrages opened, but instead Dr Harriss-Buchan was silent on this issue.
Let’s be honest, the Australian Conservation Foundation have clearly chosen to ignore the plight of the Congolli, the Mulloway, and other estuarine species and to campaign against Australian agriculture when they should, especially during the recent drought, have been campaigning for the removal, or at least opening of the barrages.
That the Lower Lakes are now full of water has nothing to do with the Australian Conservation Foundation, or government’s water reform agenda but rather natural climate cycles and the breaking of the drought with flooding rains.
The truth is there can be no River Murray estuary as long as the barrages are in place.
So, today, I ask Dr Harriss-Buchan to join with me and campaign against the barrages and for the restoration of a healthy River Murray estuary.
And to the food producers here today, I ask that you acknowledge that given the current legislation, until this is achieved, there will be limited water for agriculture, for food production. Because the environment must come first, the Lower Lakes must be saved, and given current arrangements with freshwater from upstream, rather than by the Southern Ocean.
But let us reform the current unsustainable arrangements. Let us save the Lower Lakes by removing the barrages and restoring the natural ebb and flow between the Southern Ocean and what was once a healthy estuary.
And in removing the demands of the Lower Lakes – the single largest user of water in the Murray Darling Basin – in removing this burden from the system, there will be more water available for upstream environments, communities and food producers.

Jennifer Marohasy BSc PhD has worked in industry and government. She is currently researching a novel technique for long-range weather forecasting funded by the B. Macfie Family Foundation.