I know the dams at the top of the Murray River are very low, but there is still water in the lower reaches of the system.
Today I visited the so-called Murray Mouth which is part of the Coorong National Park.
We then drove around the western perimeter of the huge estaurine lake system.
While the national consensus appears to be that some sort of catastrophe is about to befall this region — interestingly there are new housing developments and new olive orchards and more…
Crossed the ferry at Wellington – what I think is the real Murray mouth.
And there was also water in the river a bit upstream of Wellington.
I’ll be back in Brisbane tomorrow. And many thanks to Phil Sawyer for a great few days in South Australia.
Jennifer Marohasy BSc PhD is a critical thinker with expertise in the scientific method.
Jenn
I am pleased you found the mouth of the Murray so reassuring. Perhaps there is no need now for those upstream to change their water use habits !!!
As an ex South Aussie visiting there a few years ago, I was disappointed to film cows standing in the river mouth relieving themselves of solid and liquid bodily waste in copious quantities. The surrounding flat land gets very inundated in winter so that even cows pooing up to a kilometere away are using the Coorong as a toilet. The mouth of our largest river system.
Jenn, what is the conclusion you make from your short trip to SA ? – Is the water crisis another red herring just like human induced climate change ?Are Tim Flannery and Jonny Howhard wrong again ?
The photo’s are deceptive, lotsa water and green paddochs, I would like copies, same with those of yesterday.
The coorong is nearly lifeless. The mouth is not open to the sea so Alexandrina and the coorong salt accumulation is dire, like 2.5 times saltier than the sea.
When they build the dam at Wellington Alexandrina will be a salty swamp unless they remove the barrages at the mouth and let the sea invade Alexandrina, as once it did.
Irrigation and domestic water would then be unable to drawn.
The famous Coorong mullet I’ve not eaten for a couple of years.
The dam plans do not advocate the removal of the barrages. One wonders what they’re thinking.
Sorry John.
fluff4
Thank you for making real an area we’ve only read about from thousands of miles away!
Jennifer: “While the national consensus appears to be that some sort of catastrophe is about to befall this region”
On ground water depletion, a new federal focus
IMO Stream flow has always depended on two things, rainfall and soakage. Our number one reservoir is the Great Dividing Range and it is dry. The vast majority of Australia’s irrigators lie between a rock and a hard place. Many rural townships are likewise threatened.
Understanding the freshwater spring process is the key to getting a handle on the Murray Darling Basin response to this current drought. What maintains the constant flow in the headwaters of all major rivers must become the next target for government studies. Significant run off in this system is unlikely in the near future
Since much of Australia’s water has been bore water, over allocation of this resource too in the past will cause a great deal of angst as we slide further into the ravages of climate change. Bottling the remainder is our task. Capping this storage becomes as important as installing individual rainwater tanks.
Shading the soakage is not something we do well today. Natural ground cover also depends on maintaining a reasonable water table level. Lager forests act in combination with rocks and soils as a two way wick in good times by allowing for increased rain fall soakage over time. Crops on the other hand have accelerated the ground water depletion.
Gavin Bugg
It’s a lot greener than when I was there last year and the river is just as full.
Although I didn’t see any cows in the mouth itself I’m surprised to hear they’re not toilet trained down there. I wonder if the cattle in the Murray’s catchments are equally inconsiderate.
The water crisis is real, there is hardly any water anywhere. The only difference being without the irrigation industry there would be none at all to flow to SA. Without the Hume and Dartmouth Dam releases flow would be nil.
The Murray has a negligble effect on the coorong, and I think the problem could be better eased by removing the barrages rather than by freshwater flow.
thanks Jen , I had almost forgotten the number of housing developments taking shape.
John,
The key issue with the health of the Coorong, and the Murray Mouth, is that the former has largely dried up, and the mouth has been closed, on previous pre-European occasions.
The only reason that there is water there now in the middle of this severe drought is because human interventions have stored about 3 times as much water (45 GL) along the river as the annual average flow (15 GL).
This is Australia. Droughts and rivers – even rivers as big as the Murray – come and go in keeping with the vagaries of the weather/climate.
As Jen has pointed out many times, the Murray (and that includes its mouth area) is in better shape now, from our Europeanized perspective, than it has been many times in the past.
The story is actually a good news one, which might explain why the press have so much trouble telling it.
Cathy
I see there are still people looking for reasons to doubt that climate change/global warming has already had an impact.
The river has been changed, its flow restricted and huge volumes of water were once stored in dams. Along the entire length of the Murray and Darling rivers 18 billion trees have been cleared for agriculture since European settlement. In 170 years land clearing and irrigation has washed the soils away with its salt content into the murky slow moving shallow waters. Obviously this means the river (that has dried up before) is worse off now because of the changes. Salinity levels have increased while agricultural and human wastes have erupted into algae blooms.
There are ancient B/W photos showing that the river dries up but now these new photos prove the water just stagnates, which cannot be seen as an improvement. The evidence proves that this drought is even more severe than ever and that the river is on its last legs.
The term climate change should be taken to mean that Australia is experiencing a change in climate. Our nation’s water management plans were designed to exploit found rainfall patterns that no longer occur. Climate change has already established a new pattern where rain falls occur nearer to the coast. This change has established a trend leaving traditional catchments dry.
There is nothing that can be done to rectify the problem, because, quite simply, there is no water. Millions have already been spent just to keep the Murray mouth open, the sand dredgers failed to have any effect as there was no outward flow to counteract the force of the ocean. The sand was dedged and pumped into the sea where the waves carried it back to the dredger again, the effort was as pointless as that and I believe the dredger is still working!.
Lake Alexandrina is now a mud flat that can no longer supply the fresh water that dilutes the salt waters of the Cooroong. The last time I was there the smell of dead crabs was terrible, but by now the last living things would have succumed.
Further up stream the water pipes that pumps water to Adelaide disappear just below the surface. Recent heavy rains have given the state some time before plans to dam the river with a weir at Wellington are put into effect.
The Wellington weir will never have water passing over it so it will become the last dam that finally kills any chance that life will ever exist between the stagnant ditch created by human activity and the sea.
The only good thing to come out of the death of this river is an improvement in the quality of sea water off the coast from Gawler.
“The story is actually a good news one”
Cathy should tell where she got it from hey
Simon,
“Along the entire length of the Murray and Darling rivers 18 billion trees have been cleared”
That would be around 360 for every hectare in the basin. Take into account those trees that are left and the natural treeless areas and your figure seems fanciful at best.
“Lake Alexandrina is now a mud flat that can no longer supply the fresh water that dilutes the salt waters of the Cooroong”
Since the Lake is still half a metre above natural level, I will presume you are refering to the Mudflats around the lake and not the lake itself. The mudflats are mostly inundated former foreshores.
http://www.dwlbc.sa.gov.au/assets/files/USE_CoorongWQChangeDraftNov05.pdf
Have a look here and see if you think the Lakes have anything to do with diluting the Coorong. I did too previously.
“The Wellington weir will never have water passing over it”
Never is a long time, not prone to exaggeration are you?
http://72.14.253.104/search?q=cache:iPLpMfiOBnsJ:www.environment.gov.au/minister/env/2000/sp3sept00.html+15+billion+trees+lost+murray+darling+basin&hl=en&ct=clnk&cd=2&gl=au
The Murray Darling Basin is, of course, our most important agricultural region, covering just over one million square kilometres. The Basin accounts for 41 per cent of the nation’s gross value of agricultural production. Perhaps more importantly, its rivers provide drinking water for more than 3 million people, more than one third of whom live outside of its borders. But the Basin and its rivers are facing serious degradation problems, particularly in relation to salinity. This is largely the result of the cumulative effects of excessive land clearing within the basin combined with growing levels of water extractions. It is estimated, for example, that some 15 billion trees have been removed from the Basin since European settlement just over 200years ago.
According to CSIRO 16 billion trees are missing from the system.
Trees for Life published the figure at 28 billion, but I think thats exaggerating!.
I just split the difference to 18 billion, but I could be wrong because recently River Gums have been dieing in their hundreds due to drought conditions, disease and salt, so we can just keep on counting.
The trees once pumped groundwater which kept the salt in the soil from commuting to the surface. Farmers came in and replaced the trees with shallow rooted crops. Rains raised the ground water levels and bought the salt to the surface. More rain took the salt to the river and now not enough rain has raised the salinity of that catchment system.
The solution could be to build millions or thousands of windmill pumps along the system to do the job of trees, lowering the groundwater level mechanically until top soils have recovered sufficiently and trees can survive in salt free soils.
The problem at the moment is that huge areas of soil inthe system are too salty for trees to survive while most areas of clean soils are farmed which leaves very little room for forests.Besides which there is not enough water for a mass plantation of trees to survive, therefore windmill pumps geared to flush soils and leach mine salts would in decades solve the salinity problem restoring land suitable for tree plantations.
The Fed Governments knee jerk plan to save the Murray was to allow more environmental flows, thereby diluting the salt content in the river. Unfortunately there was no water available so the rivers natural or manmade backwaters are to be drained instead, but this will be a one off temporary solution which has equal or greater dangers.
The Snowy hydro is down to its last 8% and can no longer supply all those people with green electricity, but don’t tell anyone!
It seems all the changes to the river have killed it all the way to lake Alexandrina
You said
The Mudflats are mostly inundated former foreshores?’
WHAT? Like when the tide goes out, you mean?
It’s a lake; the mud you see is the bottom, so when it dries out completely it will be a saltpan.
Fairly obvious, don’t you agree?
Once able to supply fresh water into the Coorong, making the sea water brackish, Lake Alexandrina is now too shallow and too salty to effectively maintain the ecosystems balance.
The Wellington Weir plan is a SAGOV proposed temporary construction, which allowed me to be sarcastic. If indeed the rainfalls return to pre climate change levels the weir might just be overwhelmed by a torrent that might just reopen the mouth of the Murray as well, but I doubt it.
Simon, yes it is a lake with an average depth of 3m and yes it has mudflats just like it always had. You stated “it is now a mud flat” when there have always been mud flats, some 16000ha of them. They even call them wetlands.
The lakes pre european settlement could not dry out completely as the tide would flow in to replace water lost to evaporation. So no, the saltpan isn’t obvious.
“Once able to supply fresh water into the Coorong, making the sea water brackish, Lake Alexandrina is now too shallow and too salty to effectively maintain the ecosystems balance.”
Perhaps you could have a read of the study I linked and tell me if you still think the same.
How much shallower do you think the lake is?
sorry couldn’t detect the sarcasm, had a look back and still can’t.
I used an incorrect number for the MDB area, so you are closer to the mark than I thought. My apologies.
Rojo.
A few weeks, ago after heavy rains the lake seemed to have been replenished, a huge expanse of water had inundated mudflats after only just a couple of days of rain, I was amazed! Two days later the water was gone, and no evidence of the wet weather remained.
It had not been hot, so my first thought that evaporation had dried it up was wrong, it turned out that the water, no more than an enormous surface puddle, had just blown away in the wind.
The palaeontologist report is incorrect on so many levels so it’s hard to pick just one thing that might make you think again. However thankfully the authors actually locate the mouth of the Murray on the Indian Ocean, so there’s an easy place to begin ripping it apart; This geographical clanger might also give you good cause to doubt the executive summery and some indication that you should also question the study as it establishes the ancient salinity levels from just core samples alone.
Subterranean Water tables in the area are inundated by sea water which rises through the sand; this would interfere with any salinity levels in the core samples taken and make any conclusion unreliable.
The main study actually indicates that the Murray had an enormous effect on the system although in the executive summery this conclusion is reversed.
Therefore we must rely on common sense instead.
Before settlement Lake Alexandrina was tidal and a hundred years ago a barrage was put in place primarily to keep salt water from entering the lake. Before the barrage the system had the possibility of benefiting from partial flushing as the tides came and went.
This situation allowed river water to flow through the mouth at low tide and mix with incoming sea water lowering salinity levels at high tide when the tide carried a mix of water into the southern end of the lake.
The systems salinity was also diluted by the interaction from local catchments as rains added more fresh water to the dune system, so we should not presume that the river is the only source of fresh water.
In conclusion the systems salinity levels depends very much on the location from where tests are taken as flows through either the mouth, lake or local catchments determine water levels within still or stagnant sections of the system.
If water levels remain low salinity levels will remain too high throughout for the ecosystem to survive
There are only two sources of energy that power the system, the Southern Ocean and the river. These two sources of power deliver interaction of fresh and salt waters that has been undermined by human action.
For three decades between 1960 and 1990 South Australia recorded good rainfalls when much of the agriculture along the Murray was established. During this time environmental flows were only just enough to maintain life support system from the lake to the sea,15-20%. However since 1990 rainfalls across Australia have declined while a demand for water has increased. During this time policy makers have shown no effort to protect the environment. In fact the policy has been to ignore the problem until the system suffers complete collapse, which can now be guaranteed.
My mistake, the river does or did indeed flow into the Indian Ocean. I’m not sure how that can be but as feelings of patriotism now flood over me, I think we should mount a campaign to claim this slice of sea Australian.