The Lower Lakes and  Coorong extend over approximately 140,000 hectares. It is a surprising diverse environment, with 23 different wetlands types, from very fresh to saltier than the sea. It is one of the 10 major havens for large concentrations of wading birds in Australia, and is recognised internationally as a breeding ground for many species of waterbirds and native fish. The Coorong is ranked among the top six waterbird sites in Australia, based on the diversity and number of species found there. Both the Coorong and the Lower Lakes are listed as part of the Ramsar Convention, and international agreement which aims to protect the worlds most precious wetlands. The area is a an important feeding and breeding grounds for birds who then travel throughout the Murray Darling Basin, and in some cases, all the way to Japan and China. We have international agreements with these countries to maintain suitable habitats for birds which are part of our joint natural heritage. Japan and China are of course, our largest trading partners, which makes this connection pretty special. The Lower Lakes and Coorong are particularly important during periods of drought, and act as a refuge for fish and birds when other parts of the river are dry.

But the maintenance of these habitats is not the only reason that scientists and the MDBA think it is important to keep the River Mouth open. Australia is an old and saline environment. The River Murray flows across an old sea bed as it makes its way through South Australia and as a result, picks up a lot of salt which need to be flushed out of the system. A report from the Goyder Institute identifies that at least 3,500 GL of end of river flows are required (on average) to ensure there is not a build up of salt throughout the River system. Under careful management, the average flows suggested by the Basin Plan will achieve the salinity targets in the SA reach of the River Murray (see below). With no changes to the current extractions from the Murray Darling Basin, these salinity targets will not be met. This will have a major economic consequence for Adelaide, will reduce irrigation efficiency in other parts of the River system, and risks Australia’s current brand as a clean and green source of food products.

So you can see that it is not just South Australia that benefits from a healthy Lower Lakes and Coorong. But South Australia does benefit in a very important way. The city of Adelaide, home to one million people with $60B of economic production, relies on the River Murray for its water supply. Because of its limited water storages, Adelaide draws up to 90% of its water requirements from the River Murray in any one year. Even with the construction of a large desalination plant in Adelaide, one million people and $60B of economic output is reliant on the River Murray for potable water. How is this linked to the Lower Lakes? In the severe drought during the 2000′s, the Lakes water level dropped so far, there was a major risk that the Lakes would turn acid sulphate. Within a week, the acid, and released heavy metals would have moved back up the River Murray to beneath the inlet pipes for the water that is pumped to Adelaide, cutting off Adelaide’s water supply of last resort. Furthermore, increases in salinity in the River have a major impact on the lifespan of expensive infrastructure in Adelaide, so there are some important targets for salinity in the off-takes for Adelaide’s drinking water that have been agreed to, for economic reasons as much as anything else.

What is we removed the Barrages?

It is sometimes suggested that the Lakes would have been saline much more before that Barrages were put in to maintain Lake levels, and so the barrages should be removed. Such people I find are unwilling to use the same logic (ie. let’s make things how they used to be) to argue for more water for wetlands along the River, but nevertheless, lets follow the logic. The Lakes were almost exclusively freshwater (sorry, paper is behind a paywall, I can email if you want a copy), meaning that those who argue for things to return to ‘normal’ are asking for the Lakes to remain as freshwater systems. Those who say removing the Barrages would return the Lakes to an estuarine environment would also have to argue for all of the water currently diverted to be put back into the River to maintain the original estuarine condition. The argument is a red herring. There may be reasons to remove the barrages, but to return the Lakes to their original condition is not one of them.

Proposed reductions in evaporative losses from the Lakes

Ever since I can remember, there have been proposals to reduce the size of the Lower Lakes. These have been explored and usually rejected as returning poor value for money. The net evaporation from the Lower Lakes is 750 GL to 800 GL per annum. This is already built into South Australia’s long term, historic entitlement flows. This compares with total evaporation and ‘consumption’ by wetlands across the MDB system of 11,000 GL, nevertheless it is a large amount.

The MDBC explored options to reduce evaporation in the Lower Lakes. The savings identified were relatively small (10GL – 60GL) and incurred both significant costs, and some potential major benefits, including more habitat for wader birds. These options should be explored but they do not make much difference to the overall size of buybacks suggested by the MDBA in the Basin Plan.

The Murray Mouth impact on the health of the Coorong

Another argument bandied about with little scientific evidence is that the health of the Coorong is only dependent on flows from the South East. As a matter of fact, these flows are being restored to the Southern lagoon of the Coorong, but the scientific consensus is that an open Murray Mouth is required to ensure that the Southern Coorong continues to exist as a site of high ecological importance. Any suggestion to the contrary is simply wishful thinking.

The impact of the Basin Plan on the health of the Coorong and Lower Lakes

A recent scientific review of the impact of the Basin Plan on the health of the Coorong and Lower Lakes identifies that while not all environmental water requirements are met under the Guide scenarios (3,000, 3,500, 4000 GL), they represent an improvement on baseline conditions and, in some cases, they represent a large improvement. Obviously, more environmental water requirements are met under the 4000 scenario than under the 3500 scenario, and under the 3500 scenario than under the 3000 scenario, respectively. This is a useful starting point.

I would note personally, that the existing environmental water requirements, while entirely defensible scientifically, will need further refinement. I am sure there is a lot we don’t know about how water could be managed differently to achieve the same ecological outcomes. Just as I am sure that with a renewed effort to improve irrigation efficiency in Australia, we could make another big improvement as we did in the 70′s and 80′s when we spent a lot on R,D & E in this field. These outcomes are, I am confident, what the MDBA has in mind when they say that local communities will have a say in the adaptive management of water to balance environmental and economic outcomes. A lack of perfect knowledge is no reason to hold back reform, but it is a reason to ensure review points in the reform process, more research, and for all parties to retain an open mind and be willing to adapt their positions over time as new knowledge becomes available.

Socio-economic impact of Basin Plan

The Goyder Institute also undertook a socio-economic impact assessment of the Basin Plan. It misses a major component of the socio-economic impact (irrigation!) but argues that it did not have the skills to do the regional input output modelling. I would love to see some regional input output modelling of the Basin Plan. Please post a link if you see something. Nevertheless, the Goyder Institute does a fascinating analysis and comes up with some surprising results.

Some of the key papers quoted:

Options for Water Savings in the Lower Lakes and Improved Flows Through the Murray Mouth (MDBC report)

Salinity in the Lower Lakes and Coorong ( SA Government report)

Murray Darling Water Resources Fact Sheet (MDBC report)

Scientific review of Basin Plan and its implications for South Australia (Goyder Institute)

Palaeolimnological evidence for the independent evolution of neighbouring terminal lakes, the Murray Darling Basin, Australia, Fluin et al, Hydrobiologia, 591, 117-134

Analysis of South Australia’s environmental water and water quality requirements and their delivery under the Guide to the proposed Basin Plan (Goyder Institute)

Socioeconomic implications of the Guide to the proposed Basin Plan – methods and results overview (Goyder Institute)

The problem is that while the Lakes were estuarine (salty to taste but much fresher than marine), they were never marine. Jennie Fluin’s research (pdf) on the history of the Lakes suggests the Lakes were nearly always fresh. Remember that before the barrages were put in, the amount of surface water diverted for consumptive use was about 2,000 GL/y whereas it is now over 13,000 GL/y. The long-term average amount of water that used to flow through the Murray Mouth before development was 12,500 GL/y according to the Basin Plan (pdf). With current levels of development, the long-term modelled average amount of water flowing out of the Murray Mouth is about 5,100 GL/y (figure also taken from Basin Plan). Without the barrages, the system would not only become marine (assuming we artificially keep the mouth open with a dredger), it would probably become hypersaline and start to silt up. My understanding is that in the longer term, the changes that the Lakes would be a thriving marine system are unlikely. More likely, it would be a hypersaline swamp.I know there has been modelling done on this but cannot find any published work. I would be keen for others to point to where such reports could be found.

Originally it was thought that adding marine water would stop the Lakes from turning acid. My understanding is that this is not the case, and that the salts in the marine water would still result in a major acidity event. But again, I cannot find any published reports on this. I would be interested if anyone could point to them.

Currently the Lower Lakes are an internationally recognised wetland system. The reasons are many, but include that it is a nesting site for international migrating birds, and is also a drought refuge for many birds that live across the whole Murray Darling Basin system. The values of the wetland system are listed in this report (pdf). When functioning properly, the Lakes are a breeding ground for fish, and the link between the mouth and the River is necessary for some fish species to breed. These fish find their way right up the River system. Changing the Lakes would not just effect the lower end of the River, but the effects would be felt across the whole Basin.

But probably the main reason the Lakes are being kept fresh at the moment, is that if seawater was allowed to flood in, the salt would very quickly find its way up the River and contaminate Adelaide’s water supply. It would be a brave government who told a million people in Adelaide they no longer had a secure supply of water. Mind you, its also a brave government that tells irrigation communities in the River that they are going to have their allocations cut. Who’d be a politician, ah?

The only way the Lakes can be kept in their current form is to keep more water in the River so that it freshens the Lower Lakes and naturally keeps the Murray Mouth open. The Murray Darling Basin Authority suggests that a minimum of 3,000 Gl is required to achieve this plus keep other wetland systems in the River Basin healthy. By putting this much water back into the system, the River Mouth would be kept open 90% of the time. Without it, the River Mouth will only be open 40% of the time. On a side note, it is tempting to think that the River is back to normal now that it is full. But it is important to remember that this year had perfect conditions for heavy rainfalls in the east of Australia. It was an La Nina year and also the Indian Ocean Dipole was negative. Both result in higher rainfall in Australia and the two of them together happens only a few times a century, and when it does  – usually results in massive floods in the Murray Basin. We had floods this year, but the the River at the lower end is only experiencing average flows.  In the long term, without changes to water extractions, we will witness a drying of the River and Lakes again, with the resulting misery for the irrigation community and damage to the ecological systems that sustain the whole River system.

Written by Paul Dalby, 2 November 2010

• Economic report into biodiversity crisis reveals price of consuming the planet

“You can’t value nature per se, other than to say it’s priceless, and you’re part of nature and you would not exist were you not,” declares the man in charge of the biggest attempt ever to measure nature’s worth.

“But what you can do,” he continues, “is measure the economic value of services that come to you from nature.”

The speaker is Pavan Sukhdev, study leader of the UN’s three year project to measure The Economics of Ecosystems and Biodiversity (TEEB). The project should show us all how expensive the global destruction of the natural world has become and – it is hoped – persuade us to slow down.

Written by Paul Dalby, 23 May 2010

The reason we have a political process is to try to balance all of this information and all of these needs. You will never be able to model it perfectly and come up with THE right answer. We live in a political system where all ideas are contestable, even ideas based on very sound science. This is a good thing. Whenever communities have vested all knowledge and power in a few people – disaster has always ensued.

If scientists want to be influential in this world, they must be:

1. Very honest about what the science says. As we can see from the climate change debate, it does not help the cause of putting across a credible message on science when the results are exaggerated to try and build support for a particular cause. Let the truth tell its own story. In the end civilisations rise and fall on the political process. There is not much you can do to change that. Go along for the ride.

2. Very vocal about what the science says, but more circumspect about what the response should be. Scientists can appear arrogant when they presume that they know the right response. It is important to suggest policy responses and explain what you think the implications are of different approaches, but stick to your knitting and talk about what you know about most of all – the science.

3. Tell your story. People love stories, which is why singing contests, sport, soap operas and crime shows are more popular than shows about science. If you want to reach more people, put a story around what you are trying to say. Corey’s blog-post on  how frogs were disappearing because of the global appetite for frogs legs went viral because it was a interesting story. And the science message got out as a result. Some scientists  complain to me that this is “spin”. True, but not in the sense that you are trying to deceive someone, just that you are trying to get them interested. You are showing respect to your audience by “spinning” the message in an interesting way.

4. I need to hear it at least seven times before I’ve heard it. Putting out one media release, or one article or one presentation and thinking that you’ve done the job of communicating is delusional. Good communicators get their message out lots of times in lots of different ways. When your audience has heard the message so many times they are getting sick of it, (think Kevin Rudd and “working families” or Tony Abbot and “great big Labor tax”) they have finally heard it.

5. Maintain patience and pressure. It is sometimes frustrating that no action occurs even when you think it is obvious that it should. Don’t burn your bridges by taking it out on policy makers in government. You may need to work with them for many years to come, and they are likely to get more powerful over time, not less.  But on the other hand, don’t let up the pressure. Maintain a professional tone to your discussions and presentations in the media. In the end, you will mostly be respected if you keep telling the story about the science. And policy makers can be just as frustrated as you about the lack of action as you are, even if they are not allowed to show it.

I’ll finish this post with a quote from Machievelli, one of the great thinkers on political science, said that “… nothing is more difficult than to introduce a new order. Because the innovator has for enemies all those who have done well under the old conditions and lukewarm defenders in those who may do well under the new…”

True

Written by Paul Dalby on 2 February 2010

Written by Paul Dalby on 16 September 2009

Biologists like Corey should know that the selection pressure for being able to respond to immediate scary, dangerous things has been much more powerful than the selection pressure for being able to see well into the distance and respond to dangers that will effect populations down the track. Our DNA just isn’t up to the task. A few outliers and individuals who get pleasure and/or income directly from biodiversity conservation might really care, but the general huddled masses who vote people in and out of government do not so much. We might donate money or sign petitions, but we rarely vote governments in and out of power based on their biodiversity conservation policies. We also rarely choose NOT to buy something because of that companies impact on biodiversity (except dolphins and tuna – I give you that). This is not true for climate change. It was not an issue globally until there were heat waves in Europe, unseasonal hurricanes in the US and a long, long dry period in Australia. It is a direct impact that got people scared. The fickle populations who could not give two hoots about climate change the year before voted governments out of power because they were soft of climate change, and now you can buy carbon neutral beer! Seriously – a beverage MADE with carbon dioxide!!

It is not government who are the problem. It is us. Our brain is too interested in the immediate problems of how to survive, get sex and not be bored. Genetic engineering is required if you want lots of interest in biodiversity conservation. Or we need the bees to die out to show us the direct impact of no free services.

Written by Paul Dalby on 20 May 2009

At present there is a push by two local groups backed by the local media to prevent housing on the Farm. If you support the university’s woodland recovery initiative then please see the web pages below and vote yes to the question proposed. This poll is all about creating a perception that no-one wants the housing or the Woodland Recovery Initiative and its outcome may sway politicians to reject the University’s proposal.

Select “yes” on the Guardian Messenger’s online poll (just under the main headline section) to support the Woodland Recovery Initiative for Glenthorne.

http://guardian-messenger.whereilive.com.au/

Written by Paul Dalby on 22 March 2009