PASSIONATE about the wine industry, Philip White grew up in the Bremer Valley of the Lower Murray. He now lives on the opposite side of the South Mount Lofty Ranges at McLaren Vale. He tastes wine and writes about wine, and the wine growing regions of South Australia.
Today he was judging at the inaugural Currency Creek Wine Show. Currency Creek empties directly into Lake Alexandrina. Mr White describes it as, “A small, but very pretty appellation on an estuarine river system flowing into the lakes at the mouth of the Murray.”
And I love his description of the Currency Creek region more generally:
“Cross that range and you’re in rain shadow country, where Currency Creek and its neighbouring stream, the Finniss, flow out of Mosquito Hill country, Cox’s Scrub and Ashbourne, toward the south-east. Into the Murray estuary.
Over that way the stones are more aggro and tortured, and vary from the heavily-mineralised metamorphic schists of Kanmantoo, where I grew up on the Bremer River, to the intensely-varied fruitcake of chaos some big glacier dumped where the Finniss escapes the hills. It’s highly picturesque, from the almost English pubbiness out Ashbourne way, with European trees (just outside the declared region), to the wild reaches of samphire and reeds between the old river ports of Milang and Goolwa.
The vineyards seem largely to have been planted on the alluvial sands and clays of the sedimentary flats, and some terra rosa over limestone, but some have been more adventurous. Dr. Berthold Salomon, the Austrian winemaker, planted upstream on a rocky fruitloaf of glacial moraine: the complexity of the many ancient geologies shaved up, transported and dumped by massive ice has given him a multi-epoch pudding of stones of myriad mineral flavours and water-retaining capacities. A moraine terrine terrane, if you like. In these ancient parts, these are my favourite geologies for viticulture. Gimme chaos; get complexity.
But I’ve been up and down that eastern side of the range with him, licking rocks, finding the ones with the flavours that best match home.”
Mr White is not only still excited by the topography and geology of this region that borders Lake Alexandrina to the southwest, but he is also fascinated by the notion of opening the barrages.
Just yesterday he wrote at his blog:
“While the debate about the Murray-Darling reaches anarchic crescendo, there is a persistent and increasingly laudible argument that the barrages be removed from the Murray Mouth. These are a series of weirs which secure the freshwater coming downstream by holding the saltwater of the ocean out. It’s supposed to be like a dam, with the fresh river water flowing over the barrages and into the ocean. Recently, it’s been the other way round, with seawater leaking back through to the dirty polluted puddle of droughtwater within. Diluting it, if the truth be known…
“The history of our estuary has been a long string of unfortunate mistakes…
Now it has some reasonably fresh, if not exactly clean, water in it, the river system is being provided a short breathing space for these estuarine industries: down this end, dairying is also vital, but entirely dependent on a good supply of fresh river water.
The thing that scares me about all this is the ongoing popular presumption that the floods are somehow normal. These floods are not normal. Drought is normal. And ongoing.
I discussed this recently at Burra with the radical Natural Sequence Farming genius, Peter Andrews.
He pointed out that during the white exploration of its coastlines, Australia’s rivers were barely visible: there was no mighty Mississippi or Nile Delta emergent, and no surge like the hundreds of kilometers of freshwater that whoosh into the South Atlantic where the Amazon emerges from its jungle.
“The rivers here hardly ever made it to the sea,” Andrews said. “The water stayed in the country and kept it good. The rivers were explored from the interior. Somehow we’ve got to remember what it was like before us. We’ve got to learn to spread the water out, use it where it falls, take its energy and destructive force away, slow it down, and let it fill the country while cleaning and draining it in its own complex way. Slowly. If there’s any left to flow into the ocean, that’ll be good.”
And along these same lines I’ve written that if the current water reform process is truly about giving back to the environment, then we should be thinking back to a period before rivers and creeks became constricted by sheets of water running off compacted soils, before swamps were diverted, before river de-snagging and before the blasting of rock bars for paddle steamers.
As historian Bill Gammage notes in The Biggest Estate on Earth: How Aborigines Made Australia back in the dreamtime shallow streams and overflows flushed more of Australia, filling billabongs, swamps and holes, and recharging springs and soaks.
That was a time when the health of a landscape was measured less by how much water was in a river, and more by how many kangaroos it could support.
In 1901 James Cotton, a Cobar pioneer, wrote that before the district was stocked with sheep and cattle it was covered with a heavy growth of natural grasses and that the ground was soft, spongy and very absorbent.
Overstocking was a problem throughout the Murray Darling Basin particularly during the late 1800s resulting in significant land and water degradation. Overstocking transformed soils in many districts from soft and spongy to hard clay that, instead of absorbing water, caused the rain to run off in sheets as fast as it fell – to again paraphrase Mr Cotton.
In the past one hundred years there has been a gradual improvement in land management. Stocking rates have fallen, some native grasses are returning and there has been a move to minimum tillage conservation farming practices. This has resulted in a general improvement in soil structure.
The ground may not be as soft, spongy and very absorbent as it once was, but there is no doubt that when the rain now falls on the Murray Darling, much less water runs off into adjacent rivers and streams than it did one hundred years ago. This must have implications for the amount of water flowing to South Australia.
Indeed a truly healthier Murray Darling Basin would mean less water for South Australia and as I’ve argued repeatedly, don’t waste what’s left on the dammed Lower Lakes; certainly not on the Lower Lakes during drought. Instead let’s open the barrages, or at least remove the Mundoo barrage, and let these coastal lagoons fill with some seawater as once happened naturally each autumn and for longer periods during drought.
Mr White is not frightened of the idea. And if the salt water should on occasions extend beyond the Lakes and as far up the river proper as Jervois, where the off-takes for the irrigation pipeline begins, Mr White suggests that:
“They simply shoved a pipe into another place further upstream where the water was better, pumped her down and kept irrigating…”
Why not!
******
Read about Philip White and good wine at http://drinkster.blogspot.com.au
More specifically at
Tasting the End of the River
An anticipatory Mediation
Of A Brand New Wine Region
By Philip White
read about the Barrage Removalists, link here
http://drinkster.blogspot.com.au/2012/04/up-next-currency-creek-wine-show.html
And you can post a comment.
********
PS
Interestingly the blog post by Mr White links to ‘A fresh history of the lakes: Wellington to the Murray Mouth, 1800s to 1935’. This 2004 report certainly provides a lot of useful historical information about the Lower Lakes and how they were often fresh before the barrages. But the same report omits so much information to the extent that it denies Lake Alexandrina was once the central basin of a wave-dominated barrier estuary. If you are interested in a longer history consider my report ‘Plugging the Murray’s Mouth: The Interrupted Evolution of a Barrier Estuary’ that is available for download here:
http://jennifermarohasy.com/wp-content/uploads/2012/02/Plugging-the-Murray-Rivers-Mouth-120212.pdf
And there is also my recent submission to the Murray Darling Basin Authority here:
http://jennifermarohasy.com/wp-content/uploads/2012/04/MDBA_Submission_Marohasy_Abbot_April16_2012.pdf (sorry this is 10Mb)
Doug Proctor says
The engineering mind sees opportunity for “improvement” in unregulated nature. It is a reflection of how we advanced as a species. That is the characteristic’s upside. The downside is that it/we can’t leave well enough alone most of the time.
Opening the barrage is a decision made on cost-benefit analyses, with the benefit of doubt going to the status quo and previous engineering decisions. Find a higher benefit than cost for opening it, and they will enthusiastically agree. You can even use foolish, optimistic scenarios that get politicians excited. It doesn’t really matter as long as the spreadsheet shows a three digit precision.
(By the way: Since the engineering mind sees only unique “best” solutions, if a previous engineer decided that what we have today is the best solution, the current engineer must agree. To think otherwise is to reject the unique solution hypothesis AND say a previous engineer made a mistake. You don’t get an iron ring because you make mistakes. He didn’t either.)
jennifer says
Hi Doug
At the moment A$10 billion is being spent on water reform ostensibly to keep the Murray’s Mouth open and the Lakes in freshwater.
So, in short the government could save A$10 billion… if it simply removed at least the Mundoo barrage and let the Southern Ocean do the job of both filling the lake and scouring the Murray’s Mouth. This is a job the Australian Conservation Foundation, Australian Greens, Labor and Liberal parties want done by freshwater because this provides a reason for taking freshwater from upstream food producers… something currently very fashionable to advocated. Ask Malcolm Turnbull.
It has nothing to do with economics and everything to do with misguided green politics. Read my address to the Sydney Institute under ‘publications’ link from LHS column of this page.
Debbie says
Yep,
Everything to do with misguided green politics.
I would be inclined to add misanthropic and duplicitous to that description.
Of course engineering should be part of creating good outcomes Doug.
That is perfectly sensible.
Of course we are very good at improving unregulated nature…..but of course sometimes we do make mistakes…..only recognised in hindsight or recognised when circumstances/conditions change.
The desired outcomes are the sticking point here. I believe Jen is entirely correct that it is being driven by misguided politics rather than credible evidence.
Re the ‘mistakes’.
There is a remarkable lack of any accountability in this debate, which White says is at an ‘anarchic crescendo’.
You have pointed that out from a slightly different perspective.
No body likes to admit to a mistake…that’s true.
However, it is a much bigger mistake to waste $10 billion attempting to ‘cover up’ the first mistake.
There is no long term economic advantage, social advantage or environmental advantage in that behaviour!
Mark A says
Doug Proctor
“if a previous engineer decided that what we have today is the best solution, the current engineer must agree. “
Why?
Quite apart from the fact that this has nothing to do with engineering solutions, do you assert that no engineer ever made a mistake, or always found the best solution?
In my work I’m sometimes called upon to find solutions to problems caused by management decisions, that to me really were the wrong decisions in the first place.
But I’m not always in the full knowledge of why the decision were made and even if I were, can’t do a thing about them.
The barrages were built because of a political decision, foisted upon the then government by pressure groups, and politicians being politicians, the “seems like a good idea!” worked and took it up.
Nothing to do with foresight or common sense or engineers.
As a matter of fact many in the know recommended against the barrages, but like with AGW today if you go against a political agenda you have no voice, or worse labeled a “denier”.
Peter R. Smith – OAM - Mannum says
Hi Doug,
Let’s first look at Mr. White’s situation, he grew up in the Bremar Valley where if seawater were allowed to invade into Lake Alexandrina irrigation would no longer be viable, but now irrigates on the opposite side of the Mount Lofty Ranges, so now he really doesn’t care, that is obvious from his stupid comment, “They simply shoved a pipe into another place further upstream where the water was better, pumped her down and kept irrigating…” and he knows it is not that easy.
Shoving that pipeline at Jervios cost a mere $120-Million and that is straight from the River Murray unfiltered irrigation and stock water.
As I have tried to make people understand for well over a decade, if the Barrages were to be removed or opened the level of the Lakes Alexandrina and Albert and the River Murray to downstream of Lock 1 at Blanchetown would drop by 0.75-Metre and ALL off takes downstream of Lock 1 would have to be moved upstream of Lock 1.
To shift all of those off takes, I have no idea of the costs but if it was less than a couple of Billion Dollars I would be surprised.
Hi Jeniffer,
I see you are at it again, “So, in short the government could save A$10 billion… if it simply removed at least the Mundoo barrage and let the Southern Ocean do the job of both filling the lake and scouring the Murray’s Mouth”
and once again you continue to make it sound like the tides will keep the mouth open and that will be the end of it.
Please read the above and tell me how will the Lower River Murray survive during times of no flow or low flow over Lock 1.
Hi Debbie,
Good to see you are back supporting fiction!
Hi Mark A,
Irrespective of why the Barrages were built accept for in the first plan for weirs along the River Murray there was to be 26 Locks and the trade off for Lake Mulwala removing them has disastrous ramifications which can only be solved by engineering solutions.
Mark A says
Peter
You neither listen nor care what others say, just keep blowing your own trumpet.
For the last time I say this to you, engineers do not decide what to build, customers do, in this case politicians.
Keep that in mind.
Peter R. Smith – OAM - Mannum says
Hi Mark A,
How wrong you are I am extremely interested in what is being said and want to see all options put forward and discussed openly so whatever is the best solution for the Basin is the outcome.
It is my desire that the best options will be accepted and whatever they may be the Lower River Murray has to be as productive as it can be and the source of a potable water supply.
It’s about the Basin not individuals!
Ian Mott says
Here we go again. When both the science and the logic of her delusional scam fails to stand up to scrutiny in her post below she just rounds up another mug punter to flog the same snake oil from a slightly different angle. You really are a piece of work, Jennifer.
But much worse is your downright dangerous claim that barrage removal is a superior option to $10 billion worth of budget outlays. The most dangerous aspect of all green ideology to date has been the pure fantasy that leaving a modified landscape to its own ends will somehow “restore” some sort of mythical garden of eden. And what does Jennifer do when put to the test? She drags up exactly the same infantile crap as if it were some sort of intellectual breakthrough.
I have lost count of the number of times it has been explained to her that the natural operation of the asymetrical tides in that region, without the addition of very large volumes of irrigation water, is to completely close the dunes to the point where even the lakes turn into hypersaline stink holes. But she persists with this fantasy of hers that assumes the characteristics of East Coast tidal estuaries will also apply in Encounter Bay.
She has never provided even the most rudimentary scrap of evidence or science that would support her totally untenable grasp of local geophysical reality. She does a dab little jig with historical anecdotes presented out of context but little more. And worse, she has attempted to portray the conditions in 1830 as if they were some sort of norm when the evidence is overwhelming that Sturt’s Feb 1830 observations were made at the end of a very severe, 1 in 50 year drought.
Regretably, like so many PhDs in the ecological field, she has spent a small amount of time adding to the sum of knowledge under supervision only to then spend the rest of her time peddling complete bull$#it.
Hasbeen says
Ian, after years of admiring your posts, on many things, I find your rant above, & a previous one, in a similar vane on the same subject most disappointing.
It is unlike the person I came to admire to behave in such a manner, & especially give so little argument to support your view. I am used to, & expect better of you. Such a post sounds all too much like one an AGW adherent would make on his topic, & the way it is presented makes me want to say, “up yours mate”. This is not the way to have your point of view respected, or the way to make me think again about my position on the subject.
In fact it makes me want to make a smart ass comment such as, “is your sciatica playing up”, so I will.
If you do wish to get others to think about your position, perhaps a bit more evidence would help. Without that I’m inclined to think “so what”. Perhaps we should close SA down, or perhaps give it to the boat people. To “save” it appears to be becoming too expensive to the rest of Oz, & perhaps not worth the effort.
You see, more than one can become unreasonable.
Johnathan Wilkes says
Hasbeen
I have also remarked on Ian’s tone before, asking what has happened to make him so abusive and antagonistic towards Jen, but it’s obvious that it is a private matter.
Still as you, I have read his contributions on other outlets and while not actually “admired” them I found most of them well reasoned.
There is no need for this kind of public airing of disagreement, sort it out privately.
Please?
Jennifer Marohasy says
Johnathan and Hasbeen
There is no “private matter” that I know about.
Jennifer Marohasy says
Hasbeen
I’ve been collecting maps and photographs of the Murray’s Mouth before the barrages, including to get an idea of how the sand used to shoal back then. There is a fascinating aerial photograph from I think 1927 showing a sand spit following a really deep but narrow channel from the ocean across towards the Mundoo channel almost blocking the Goolwa channel… With memories of holidays at Noosa back in the 1970s when aged about 10 a group of us used to jump into that ebb tide rushing around the south bank at Noosa Woods towards the River’s mouth. We thought it a great lark being carried by those waters.
Philip WHITE says
Well goodness gracious me.
Tony Price says
Hasbeen April 29th, 2012 at 10:08 pm:
“Ian, after years of admiring your posts, on many things, I find your rant above, & a previous one, in a similar vane on the same subject most disappointing.
It is unlike the person I came to admire to behave in such a manner, & especially give so little argument to support your view. I am used to, & expect better of you. Such a post sounds all too much like one an AGW adherent would make on his topic, & the way it is presented makes me want to say, “up yours mate”. This is not the way to have your point of view respected, or the way to make me think again about my position on the subject.”
Indeed, I’ve read several of Ian’s posts in the past, and he made a lot of sense, with much data (though thin on references). He doesn’t argue, or present data to refute, but makes condescending and disparaging remarks, insults, and just repeats himself ad nauseam. He’s doing himself, his reputation, and his mental health no favours. So far I’ve not seen him accept that anything anyone else says or cites might possibly be true or relevant in any way. His mind is made up. In a blogger and commenter, that’s lamentable. For many politicians or AGW sycophants it’s par for the course. I normally refuse to label anyone, but……
His fixation with daily tidal range (on an earlier thread) rather than actual height makes no sense. Someone standing on the beach cares not a tinker’s cuss what the current tidal range is, but whether he’ll wet his boots unless he moves inland. A boat skipper wanting to enter harbour (or the Murray Mouth) isn’t concerned with tidal range but with tide level and maybe grounding his boat.
Insulting commenters is one thing, though most of us abstain unless retaliating under duress; repeatedly insulting a blogger and her guest posters while taking advantage of her hospitality and tolerance to push (and push, and push again) his case is outside the pale. I wonder at Jennifer’s patience. I wonder if she’ll consider marriage (or at least a “meaningful” relationship) if she’s single or contemplating divorce. I wonder… no, I’d better not.
PS – is Peter R. Smith possibly Ian’s alter ego? I see similarities.
John Sayers says
Ian Mott is just being his normal arrogant self.
His solution is to put pipes under the sand dunes to fix the Coorong, what would you expect from an accountant/slum landlord who fancies himself as an environmentalist.
Debbie says
Getting back to the post,
I think it’s also interesting that White points out that droughts are more prevalent.
That is probably a bit of an over exaggeration and really only applies to the level of flows at the bottom of the system.
Flooding is also common but is far more sudden and dramatic (and over) than drought.
The real point is that the ‘environmentalists’ are refusing to recognise the realities of this system and are instead relying on a romantic illusion about the mighty river Murray and an international convention to argue a case for more fresh water to be forced to the lakes.
So even if Ian’s disagreement with Jen is valid, it doesn’t change her major argument that this whole debate has been driven by misguided green politics and that we’re likely in the process of senselessly wasting billions to solve the wrong problem.
Peter R. Smith – OAM - Mannum says
Hi Tony,
Re, “PS – is Peter R. Smith possibly Ian’s alter ego? I see similarities” well that’s wrong but we both agree the removal of the Barrages will cause massive problems for the Lower River Murray.
Hi John,
There have been many suggestions/ideas put forward as ways to fix the Murray mouth and Coorong problems and Ian’s idea of pipes is but one of the many.
The Ngarrindjeri have looked at many of these ideas and will not allow excavation on or through the Younghusband Peninsula that is why the SA Government have done the planning to pump out the Southern Lagoon.
Hi Debbie,
Re, “So even if Ian’s disagreement with Jen is valid, it doesn’t change her major argument that this whole debate has been driven by misguided green politics and that we’re likely in the process of senselessly wasting billions to solve the wrong problem” by wrong problem I suppose you mean the Barrages which is wrong, we know must be upgraded, but removed NO WAY!
John Sayers says
Peter – Ian’s approach is one of a pragmatist – he accepts that the majority of people on the case want the lakes to remain fresh, so he has come up with a solution accordingly.
Ian Mott says
Hasbeen, kindly take a look at http://regionalstates.wordpress.com/2012/04/17/barrages-and-murray-mouth-mirages/ and then tell me why Jennifer so consistently sidesteps the major flaws in her scam.
Explain to me why it is appropriate for anyone involved in public policy to make highly misleading statements about the size of the benefits of an action, in this case savings of river water evaporation. More than a third of her claimed million megalitres of evaporation savings come from local rainfall and will continue to do so if the lakes are fresh or sea water. Jennifer defended that gross misrepresentation of fact on this blog and others.
When it was pointed out to her that no substitution of sea water for fresh can take place while ever there was more than a measly 500,000ML of annual flow (ie 19 out of 20 years) she claimed that substitution would occur during the low-flow parts of the year. My submission to the MDBA, reprinted at the above link, explains in great detail how the low-flow period also coincides with the lowest evaporation rates and the highest rainfall, and highest local runoff. The net result being that in 9 out of 10 years there is no net evaporation deficit that could be taken up by sea water.
The only time the removal of barrages would actually produce a meaningfull substitution is in the next 1 in 50 year drought like the last one and the one observed by Sturt in 1830.
And I make no appologies for taking a hard line when a person who has held themselves out as a champion of honesty and full disclosure in science starts employing all the obfuscation and sleaze that we have all spent the past two decades opposing.
Remember that it is not Ian Mott who has defined the key elements of fraud, it is the courts. And the facts are capable of establishing that Jennifer has made;
Serious misstatements of omission,
misstatements of fact rather than opinion,
made with a knowledge of of their untruth, and
made with an intention that they be acted upon.
If she did the same in a prospectus or company return she would cop a stretch.
Debbie says
Peter,
Suppose away all you like,
You repeatedly accuse me of having opinions about those barrages that I do not have. You are also very rude, very emotional and dismissive.
Pasting a comment and then saying Crap or no way or that’s wrong or numerous variations thereof is not achieving any valuable contribution to this discussion….neither does a personal dismissive comment like the one you made about Peter White.
That’s called ‘shooting the messenger’ and it is becoming a particularly unnatractive and unproductive tactic of yours.
You either have a comprehension problem or Mark A is correct.
I agree with Jen that this debate all along has been driven by misguided green politics. There is no question that the area under discussion is influenced by its coastal position yet the ‘fresh only’ and the refusal to recognise the power of oceanic influences is bewildering.
As the submission from a person who works in the business of water management and who is also a South Australian and who is also very experienced and well read on this issue says:
‘The great myth about the volume of water keeping the mouth of the Murray River clear and a lack of river water being the cause of the mouth silting up must be the greatest con ever perpetuated. Can you tell me that the MDB Rivers can counter the power and force of the Southern Ocean which shapes the littoral coast where the purported Murray mouth is?
I want someone to tell me where Australia’s greatest river system’s estuary is and why it hasn’t developed a delta if it is such a land builder.’
There is a an article in last Friday’s Australian by Josephine Kelly that helps to explain why this is happening, I don’t know how to attach it but maybe others here have read it and could attach it?
The tilte is: The Strange Idea Behind Ecological Law.
I definitely suggest Peter reads it.
I also agree with John’s appraisal of Ian’s approach…. first and foremost he is focusing on solutions that could perhaps be more palatable to the majority of South Australians.
After all, the majority of the problems there are in fact man made and as Doug and Mark A have both explained, they need to be correctly identified and then will require a man made solution.
I find it rather predictable that Peter has focused on yet another obstacle rather than discussing the actual merits or otherwise of this proposal or any other proposal other than his own….which he also repeatedly complains is fraught with insurmountable obstacles.
John Sayers says
here’s the article Debbie.
http://www.theaustralian.com.au/business/legal-affairs/the-strange-idea-behind-ecological-law/story-e6frg97x-1226339201916
Susan says
Interesting to note Peter Andrews quoted in Philip White’s blog saying “…We’ve got to learn to spread the water out, use it where it falls, take its energy and destructive force away, slow it down, and let it fill the country while cleaning and draining it in its own complex way. Slowly. If there’s any left to flow into the ocean, that’ll be good.”
I came across some interesting newspaper letters to the editor by some early settler landowners in the 1900’s. They describe the interaction between lake and sea water, how water used to drain through the Mundoo Channel, and how the barrages would block this drainage of sea water which they predicted would make the Lakes saltier in the long run.
“I notice with pleasure that a petition has been presented to Parliament against the Murray Mouth barrage, and that Mr. McDonald has asked if a modified barrage could not be erected. Even the first proposed would not keep out the sea water at high spring tides. The river now at Mundoo Island is pure; but with the high tide and high wind, although the river is 18 in above summer level, this tide comes up the Mundoo channel and makes it as salt as the sea. If any obstruction were erected all these channels and the lake would be continually salt, or the fresh water could not force the salt water back again only to the level of the barrage, while with the higher fresh water the salt water would go back to low tide level.”
http://lakesneedwater.blogspot.com.au/2011/09/side-effects-of-no-tides.html
John Sayers says
Susan, Peter Andrew features in tonight’s Australian Story.
http://www.abc.net.au/austory/
Debbie says
Mark A,
It looks like you might need to take yourself over to the blog: http://drinkster.blogspot.com.au/2012/04/up-next-currency-creek-wine-show.html
and defend your name….AGAIN!
They have commented on the discussion here and they have mixed you up with Peter.
What is it about your post name Mark A that causes that happen to you quite often?
🙂
Mark A says
Don’t know Debbie, but it doesn’t matter.
I only post on our trade related blog and here, so I can’t imagine how they confuse me with others, probably just a cut and paste error, most likely. Unless there are several MAs out there?
Thanks for the reminder.
Ian Mott says
Tony Price only highlights his ignorance when he disparages my “fixation with daily tidal range (on an earlier thread) rather than actual height makes no sense. Someone standing on the beach cares not a tinker’s cuss what the current tidal range is, but whether he’ll wet his boots unless he moves inland”.
It is, after all the amplitude of the daily tidal range that determines the volume of water in each tidal flow, which in turn determines the velocity of that flow, which then determines the volume of sediment that is moved by that flow. All three of these key elements are capable of quantification. If he was even vaguely interested in understanding what is actually going on then he would recognise this quantification as essential facts. But no, he adopted the perspective of this weeks day tripping mug punter standing on the beach, with a vague idea of what he was actually observing, and concerned only by whether he’ll wet his boots. We can only be thankfull his focus is not on his navel or his genitalia.
And Hasbeen, this is the “tone” I have always applied to illinformed boofheads influenced primarily by misplaced tribal loyalties. You just found it acceptable when it was directed at those you disagreed with but are obviously now having trouble grasping the fact that members of your own tribe are demonstrably capable of deserving the same response. Have you bothered to get up to speed on the substance of my objections to this scam yet? Or are you still filling in the blanks of your own, and Jennifer’s narrative with only 15% of the brief.
The truth always comes first, daylight second, and bull$#it can please itself.
John Sayers says
“Tony Price only highlights his ignorance”
and you follow it up with yours.
Nature determines the tidal flow.
The Coorong/Lower Lakes is a natural system. Why can’t you understand that?
Jennifer Marohasy says
Tony Price
Thanks for the great info and link at the earlier thread.
http://jennifermarohasy.com/2012/04/answers-for-simon-birmingham-shadow-parliamentary-secretary-for-the-murray-darling-basin/
In particular the following is relevant here so I’m filing below:
*****
From Tony Price
Tide data for Goolwa Beach is actually BOM data for Victor Harbor.
The Data
Tide times data has been adjusted for daylight saving where and when applicable. WillyWeather interpolates its tide times for many locations by converting the tide forecasts provided by the Australian Bureau of Meteorology for standard ports, and data from the Australian National Tide Tables. The tide times on the Goolwa Beach tides page have been adjusted by 0 mins for low tide and 0 mins for high tide to the official tide times for Victor Harbor. Tide height data is for Victor Harbor, no adjustment has been made.
http://tides.willyweather.com.au/sa/fleurieu-peninsula/goolwa-beach.html
I can not only read a tide table, I can avoid cherry-picking periods shorter than the lunar cycle to “prove” my argument.
You [Motty] consistently refer to tidal range, though anything above MSL cares not a tinker’s cuss what the tidal range is, but peak tides. Though the data on your favourite tide site has a coarse resolution of 0.1m ( BOM says Victor Harbor is consistent with the Murray mouth), it’s within +/- 5 cm of the BOM data, so I can use the WillyWeather charts for quick analysis. Over the period 1st April to 28th April, peak tides were as much as 0.6m above MSL, almost double the 0.35m your [Motty] tidal range suggests.
Your statement [Tony quoting Ian Mott]
“There is generally only one tide each day, and that is only during the 50% of the lunar cycle when they even take place at all. And, aside from storm surges, they only exhibit a tidal range greater than 70cm on 4 or 5 days each month.”
This statement bears examination. “When they even take place at all” is saying that there are no tides whatsoever for 14 of the 28 days?
You [Motty] need a reality pill, or to take off your blinkers.
There are two distinct tides, though often of disparate heights for 14 of the 28 days 1st-28th April 2012.
Minimum daily tidal range is 0.3m, maximum is 1.1m, peak tide is 1.3m. I’ve estimated MSL as 0.7m which is being generous, and means that peak is at least 0.6m above MSL, and there are 8 other days with identical peaks.”
End of quote.
****
Noted. Cheers
jennifer says
Tony Price
Also worth having a look here: http://www.abc.net.au/news/2012-04-26/barrages-lower-lakes-closed-murray-salinity/3973258?section=sa
Water authorities in South Australia have closed the Goolwa and Mundoo barrages on the lower lakes near the Murray mouth, due to high tides.
Other barrages remain open as high flows move downstream into the sea.
Richard Brown of the Water Department said there could be isolated spikes in salinity from sea water entering the lower lakes region.
“High tides are normal in autumn in South Australia, they’re often known as king tides and they’ll occur usually in April and May each year,” he said.
“It’s not something that is going to persist for very long.
“The flows at Lock One remain high at around about 50,000 megalitres a day, so you’ll appreciate there’s plenty of water coming down into the lower Murray.”
****
Cheers
Ian Mott says
For a guy who accused me of cherry picking, it is quite telling that Tony Price did not respond to my specific invitation to also look at the November tide graphs as a point of comparison to the April ones. Nor did Jennifer, despite the fact that she posted this quote above,
“High tides are normal in Autumn in SA, they’re often known as king tides and they’ll occur usually in April and May each year,” and, “Its not something that is going to persist for very long”.
Yet here we have Price and Marohasy employing a classic cherry pick to mislead readers into thinking my statements about tides has no basis in fact. So I invite readers to go to Willyweather again and start at May 2011 and right arrow through the entire 12 months to gain an understanding of the whole truth and nothing but. http://tides.willyweather.com.au/sa/fleurieu-peninsula/goolwa-beach.html
Note that Price’s focus on total height (in April) is not replicated throughout the year. And he has been very misleading in quoting the height of the main daily inflowing tide without mentioning that the outgoing phase often only goes back to half the amplitude before a small rise leads to a further drop to near the original bottom, depending on the phase.
And after going through a whole 12 month sequence again I am pleased to have been reminded of another flaw in Jennifers science that I had failed to mention before. The time of year when evaporation is highest is also the time when river flows are highest BUT it is also the time when mean sea level is lowest. And when mean sea level is lowest it is also when potential for tidal intrusion is least.
This anti-barrage scam is looking more and more like a really ignorant cargo cult by the day. But don’t mind me. If you really want to immitate Gillard, and have your good name attached to some really stupid ideas for the rest of your life then, by all means go for it.
Denis Webb says
Motts
Jen and Tony Price have done no damn cherry pickn.
They have been as honest as you a scoundrel.
As Jen has written in all of her many reports and submission that you can’t have read: the Southern Ocean comes pourn in through the Murray’s mouth each autumn when the southwesterly winds pick-up and with the king tides.
Until today you were denyn king tides.
Peter R. Smith – OAM - Mannum says
Hi Dennis,
I may be wrong but are you saying/indicating that the Murray mouth would not be closed by tidal movement if the Barrages were removed?
Yes we have king tides which deposit quite a load of sand with the incoming tide but do not remove all of that load with the outgoing tide unless there is sufficient freshwater flowing out with the tide, which under natural (which can never be again) conditions, would keep the mouth open but alas when low inflows occur in the Basin with the diversions the mouth would be closed and the damage would catastrophic in the Lower River Murray.
Debbie says
Peter?
Pardon?
You need to clarify that comment about the returning power (or lack thereof) of a king tide.
You also need to explain why there was no delta either forming or formed before the barrages were constructed if natural conditions were reversing the power of intermittent King tides.
jennifer says
Peter and Debbie
You are both making very relevant comment. There has been a very significant change in how the sand shoals at the mouth since construction of the barrages. The ebb tide which once had great force on King Tides has perhaps lost its grunt since construction of the barrages, in particular the Mundoo barrage.
Peter R. Smith – OAM - Mannum says
Hi Debbie,
I realise you do not know the area but what I am saying is incoming tides deposit more sand than outgoing tides remove unless the outgoing tide is combined with a large amount of freshwater flowing out of the mouth. As we (white-man) has removed much of the amount freshwater outflows there would be a permanent build up of sand and silt and the mouth would close.
Ian Mott says
Debbie, take another look at the graphs at willyweather, or a first look if you have not done so, and observe the number of times when the pattern shows a steep inflow over about 8 hours and a gentler slope on the outflow over about 16 hours. This can only mean one thing. The volume of water that came in took twice as long to go back out again so the speed of the outflow was only half the speed of the inflow.
And as I have had to state ad nauseum in every discussion on this topic, THE VOLUME OF SEDIMENT THAT IS MOVED BY WATER VARIES BY THE SQUARE OF THE VELOCITY. Ergo, the sediment moved on the outflowing tide is only a quarter of the sediment deposited by the inflowing tide. Historically, this imbalance was usually remedied by the 12 million megalitres of mean annual flow that is now diverted to Adelaide and upstream irrigation.
And as I have also said ad nauseum, this is not the case on the east coast where tides are much more symetrical. Yet, Jennifer has consistently avoided this core principle of fluid dynamics and has yet to provide us with an alternate principle, other than the most pathetic vaguaries based on nothing more than her observations of east cost estuaries.
And Debbie, the reason why a delta didn’t form there was because the silt load and the runoff volume never got within cooee of the volumes discharged by the well known delta forming rivers like the Mississippi or Nile. The “once (in a blue moon) mighty Murray” has never been in the same class. But the river flow was still able to reverse the tidal deposition because most of the time the tides are so piss-poor. You can be excused for not understanding this but the fact that Jennifer didn’t get it is just more evidence that she is out of her depth.
So whats the story Jennifer. Are you contesting the fact that local tides are asymetrical?
Do you have an alternate theory to explain how much sediment flowing water can transport?
Does anyone with an engineering degree or hydrologist agree with your theory?
And if so then HOW, EXACTLY, DO YOU reconcile local flows with local sediment loads?
Debbie says
Ian,
thank you for that.
The point of the question was indeed that the Murray is not like other rivers and while sometimes able to shift sediment it was not as powerful as Peter claims and also, by association, flushing more water down it, out of season, will not solve the issue of a silting mouth.
It does not have the power that would be necessary to consistently counter the influence of the Ocean. If it did, that area there would look very different.
I accept that I may not understand the tides as well as you and/or Jen but I do understand the river/s in the southern MDB. What Peter claims about that mouth is not possible even if all upstream diversions were stopped. In times of low inflows, with engineering works still in place down there, the river would unlikely prevent mouth closure. It is not a good solution.
BTW I am a fan of your work on solving the developing problems in the LRM especially re the Coorong.
Peter R. Smith – OAM - Mannum says
Hi Debbie,
Could you please explain, “What Peter claims about that mouth is not possible even if all upstream diversions were stopped?”
As Ian points out, “Historically, this imbalance was usually remedied by the 12 million megalitres of mean annual flow that is now diverted to Adelaide and upstream irrigation.”
Historically prior to ‘white man’ the average out flow through the Murray mouth was calculated at 730-Gigalitres per year.
I CERTAINLY DO NOT want the diversions removed what we want is the Barrages COMPLETELY up-graded the remedial work carried out to re-instate Lake Albert and a full investigation into Lock Zero.
With the above completed we can then see our future track to manage the Lower River Murray successfully!
Re, ‘The point of the question was indeed that the Murray is not like other rivers and while sometimes able to shift sediment it was not as powerful as Peter claims and also, by association, flushing more water down it, out of season, will not solve the issue of a silting mouth” no what I have been saying is that if the Barrages were removed the mouth of the Murray River would close.
So I am in complete agreement with Ian, “It does not have the power that would be necessary to consistently counter the influence of the Ocean.”
Debbie says
Peter,
This is what you claimed:
Yes we have king tides which deposit quite a load of sand with the incoming tide but do not remove all of that load with the outgoing tide unless there is sufficient freshwater flowing out with the tide, which under natural (which can never be again) conditions, would keep the mouth open but alas when low inflows occur in the Basin with the diversions the mouth would be closed and the damage would catastrophic in the Lower River Murray.
‘Natural (which can never be again) conditions’ did not consistenly ensure the mouth was kept open because Peter, if they had, the natural landscape would be different there.
It was actually my comment that you have pasted last, not Ian’s.
Here:
So I am in complete agreement with Ian, “It does not have the power that would be necessary to consistently counter the influence of the Ocean.”
So maybe you meant you are in complete agreement with Debbie?
That has always been my point….the river does not naturally do what has been claimed on a consistent basis….regardless of upstream diversions….it doesn’t work that way and never has either before or after regulation.
It is not the mythical ‘mighty river Murray’ that has been fabricated in the court of public opinion.
Under natural conditions, sometimes the outflows influenced behaviour at the mouth and in the lakes and sometimes the ocean did.
Nobody really wants natural conditions restored there Peter….least of all SA.
In one very important regard Jen and Ian are both correct…..this debate has been driven by misguided green politics….as well as a completely inappropriate and unproductive knee jerk reaction to a millenium drought.
Peter R. Smith – OAM - Mannum says
Hi Debbie,
I regret my error it was what you (Debbie) said not Ian so I agree with the Debbie who has NOW ADMITTED what I have been saying for over a decade that NATURAL can never be restored again or for the Lower River Murray and our Lakes Alexandrina and Albert the removal of the Barrages (To return to the Tidal/Estuarine of prior to the Barrages) would be a disaster.
So re, “So maybe you meant you are in complete agreement with Debbie” yes the Debbie who has changed her stance!
Re, “That has always been my point….the river does not naturally do what has been claimed on a consistent basis ….regardless of upstream diversions….it doesn’t work that way and never has either before or after regulation.
It is not the mythical ‘mighty river Murray’ that has been fabricated in the court of public opinion’ “the regardless of upstream diversions” is drawing a long bow (I totally agree with the diversions at the present time) but if there were no diversions and infrastructure the NATURAL occurrence would ensure the history was freshwater accept for about 20% of the time.
Re, “Nobody really wants natural conditions restored there Peter….least of all SA” and “In one very important regard Jen and Ian are both correct” I am sorry I can’t agree as Ms. Marohasy wants the Barrages removed!
Ian Mott says
Thanks Debbie, but your belief that the river isn’t powerful enough to counter the influence of the sea is based on two flawed assumptions.
You appear to assume that the conditions described by Sturt are representative of pre-barrage norms when he was actually describing conditions at the end of a 1 in 50 year drought similar to conditions in 2009.
You also assume that tidal and oceanic influences outside the dunes cannot be modified by conditions inside the mouth. One of the things I have also been saying ad nauseum is the fact that the barrages themselves significantly reduce the impact of tidal and oceanic factors by reducing the volume of the tidal prism.
The tidal prism is the volume inside an estuary mouth that is subject to tidal variation. So a 1000 hectare area that experiences a 1 metre tidal range (ie 10ML/ha) will have a tidal prism with a volume of 10,000ML. And this 10,000ML then forms the upper limit of inflow volumes that a 1 metre tide can deliver.
If the area was 2000ha then the upper limit of inflow volume with the same tidal range would be 20,000ML and it would mean that, assuming the same mouth cross section, the flow would be twice as fast and it would bring in four times more sediment than it would for the 1000ha prism area.
So when the barrages were built they reduced the volume of inflows over the entire range of tidal amplitudes at the very time when the river’s capacity to deal with tides was being reduced by higher extractions. If the barrages had not been built the rivers reduced capacity to deal with tides and storm surges would have resulted in a semi-permanent inflow delta which then further restricted tide flows to the point where the conditions described by Sturt became the norm.
It should also be noted that the actual shape, and therefore the volume, of a tidal prism is altered by distance from the mouth and the size of the mouth opening. So a 1 metre tide on the beach can be less than 50cm at the Tauwitcherie barrage for the simple reason that the tide will already have turned by the time 50% of the water reaches its destination. The prism is irregular in both area and height.
And as sediment is deposited inside the mouth, and that deposition must end up at the bottom of the channel, it means that there will be no actual inflow until the tide has already risen higher than the deposited sediment. And this then reduces the time in which the inflow at the top half of the cycle can flow which then produces an even lower tidal range near the barrages.
And this is why I continue to point out that the only way to fix the problems at the mouth is to use pipes under the dunes to get half of each tidal volume into the estuary in a way that does not bring sand with it. And when the pipes have valves that don’t allow water to flow back out through them then this water will have to go out through the mouth and produce an equilibrium flow (ie twice the outflow over twice the time) and an equilibrium sediment flow.
Barrage removal is downright foolhardy if this equilibrium is not already in place. Only when the equilibrium is achieved with a continuous supply of cheap, abundant and reliable cycling sea water can a portion of existing fresh water outflows be diverted to other ecological or economic uses.
And if the South Australians want to use their share of the resulting water savings to maintain a fresh water lake then that is entirely their own choice.
Debbie says
Peter,
I did not say Ian and Jen agreed about the removal of the barrages….they quite clearly don’t…so you have neither disagreed or agreed with my comment about the fact that this debate has been largely driven by misguided green politics and an inappropriate knee jerk reaction to a millenium drought.
It’s rather lucky for us all, including SA, that natural conditions were not in operation for the last period of drought …20% or otherwise….don’t you think Peter?
That 20% argument is not productive or practical because SA doesn’t want to be devoid of access to fresh water from the Murray River even 1% of the time I would imagine….I certainly wouldn’t want to be if I lived there.
The rest of your comment is once again accusing me of changing my stance….that is not correct… and therefore there is no point in me engaging with you.
Ian,
Thankyou for your explanation…I do not believe however that I am operating under flawed assumptions…. I just apparently have not made myself clear?
I don’t pretend to know as much as you as far as tides are concerned…..I do however understand the way the southern MDB rivers and regulatory systems work and the inflows into our largely ephemeral system do not have the ‘consistent’ power to maintain a stable river mouth and extra flushing from upstream storages will not achieve that either as they are physically incapable of emulating what would be required. (except in a mythical computer model)
In fact, I don’t believe that the river mouth or the Coorong was ever ‘naturally’ interested in being ‘stable’….it’s us humans that want to create a stable environment there.
I don’t have a problem with that BTW….I’m just tired of the duplicitous ‘environmental and natural’ justifications and the very dodgy ‘end of system flows’ hydrological modeling that uses meaningless ‘long term averages’…to justify a number and claim that will ‘fix’ the problem.
I am aware that Sturt’s descriptions apply to drought conditions….that was not what I was basing my comment on….but drought conditions and low inflow conditions are nonetheless quite common in our ephemeral MDB system and they commonly resulted in no flows at the bottom of the system.
Those no flow conditions sometimes only operated for a few days or weeks, sometimes for a season or two and then in severe drought conditions for years.
I entirely agree that if SA wants to maintain a fresh water lake then that is entirely their choice….but it must be done by using a sensible solution there…not the one currently on the table…..your solutions from my perspective appear to have a great deal of practical merit.
Hope that helps?
Peter R. Smith – OAM - Mannum says
Hi Debbie,
Whilst there is some truth in, “the fact that this debate has been largely driven by misguided green politics and an inappropriate knee jerk reaction to a millennium drought” your other comment, “That 20% argument is not productive or practical because SA doesn’t want to be devoid of access to fresh water from the Murray River even 1% of the time I would imagine….I certainly wouldn’t want to be if I lived there” I don’t believe it is not productive as it is a fact of history but your other part of the comment, “I certainly wouldn’t want to be if I lived there” was fact and that is how we feel and want the rest of Australia to support us!
Re, “I entirely agree that if SA wants to maintain a fresh water lake then that is entirely their choice….but it must be done by using a sensible solution there…not the one currently on the table…..your solutions from my perspective appear to have a great deal of practical merit” I want to see Ian’s proposal discussed as well as all the others but as for what SA wants it must be remembered that the cost of maintaining Murray Darling Infrastructure is shared, NSW 38%, Vic 35% and SA 27% so decisions must be made by those three States and the MDBA.
Tony Price says
I’ve been otherwise engaged , so I’ll respond to comments from others, and misrepresentation from Ian here in bulk, and in two posts so it doesn’t break my browser.
Ian Mott April 30th, 2012 at 5:39 pm
“It is, after all the amplitude of the daily tidal range that determines the volume of water in each tidal flow, which in turn determines the velocity of that flow, which then determines the volume of sediment that is moved by that flow.”
No, it’s the ability of the tides to flow over an obstacle which matters, and tidal range has no direct bearing on that, unless the peak tide is greater than the height of that obstacle. If there’s little difference between the peak above the obstacle height, and the next trough, any backflow is reduced. Tides with large range but where the peak is barely higher than the obstacle, or even below the height of the obstacle have little or no effect on intrusion, but aid outflow. Too simple for you to understand?
“We can only be thankfull his focus is not on his navel or his genitalia.”
More insults – the refuge of the intellectually and factually barren, Your invective is falling like sea water off a duck’s back, or peak tides of LOW tidal range over the sand at Murray Mouth. You began last year by informing and entertaining me, continued this year by beginning to irritate me, and have finally, by your repetitive and invective-ridden retorts and rants (rather than measured and reasoned responses) managed to get me involved in what might be called “Jennifer’s pet topic”. For that at least, I thank you.
Jennifer Marohasy April 30th, 2012 at 9:18 pm : Thanks for the copied summary, saved me the trouble. BTW you didn’t respond to my earlier tentative proposal. I’m crushed, devastated, yet strangely unaffected, and remain of sound mind.
Denis Webb May 1st, 2012 at 3:29 pm: Thanks for your support. Do you know where I can get one? Cherry-picking is anathema to me, and to Jennifer too, who also has an open mind, and has demonstrated that continually.
Ian Mott May 1st, 2012 at 11:51 pm:
“Debbie, take another look at the graphs at willyweather, or a first look if you have not done so, and observe the number of times when the pattern shows a steep inflow over about 8 hours and a gentler slope on the outflow over about 16 hours. This can only mean one thing. The volume of water that came in took twice as long to go back out again so the speed of the outflow was only half the speed of the inflow.”
No it doesn’t “only mean one thing”. Only the part of any cycle which results in inflow is relevant to that inflow; the rest of the entire cycle below that level results in outflow if the level inside the mouth is high enough. Your “2 to 1” is insupportable unless you take the actual height into account, and not the range, as you continue to do. You don’t know, nor can predict, the volume of water which would flow in, nor that which would flow out; it depends on the height of the tide, the level of water inside the mouth, the change in that level due to river flow, and the cross-sectional profile of the mouth. There’s no indication on any sea-level or tidal charts of the level of, nor cross-sectional profile of, the Murray Mouth. I don’t know it; you don’t know it. Your assertions are unjustified assumptions.
“And as I have had to state ad nauseum in every discussion on this topic, THE VOLUME OF SEDIMENT THAT IS MOVED BY WATER VARIES BY THE SQUARE OF THE VELOCITY. Ergo, the sediment moved on the outflowing tide is only a quarter of the sediment deposited by the inflowing tide. Historically, this imbalance was usually remedied by the 12 million megalitres of mean annual flow that is now diverted to Adelaide and upstream irrigation.
It’s an unjustified and illogical obsession.”
You don’t need to shout, though perhaps it’s the only way you see of getting your message across, unrefined, unhoned and unpolished by comment from others as it remains to this day. Your mind is closed, but your mouth is wide open. You hear but you don’t listen, you see but you don’t identify, you touch but you don’t feel, though perhaps you are touched, if you know what I mean, though I doubt you know what anyone means.
No, it’s the volume of water which is proportional to the square of the average velocity of the flow. The volume of sediment depends on how the sediment is transported, which depends on the nature of the sediment, and any turbulence in the flow. Sand and larger stony sediment will tend to stay near the bottom of the flow, where the flow will be lower. Fine sediment will be mostly in suspension, and will “go with the flow”. There’s likely to be a much greater proportion of the latter in river or lake water. Because the heavier sediments stay towards the bottom, outflow favours suspended sediment. That combined with the slower outflow results in a net inflow of sand. “ad nauseum” – I said it, you said it, except I spelled it correctly.
Ian Mott says
Price, you clearly personify what could be termed “an articulate bimbo”. You have mastered the format of a coherent argument but without any of the substance. You plucked your understanding of sediment transportation out of your own backside and, very conspicuously, failed to provide any means of calculating the volume of sediment. And this reinforces my very first assessment of you when you blathered on about “potential inconsistencies” when, at the time, you had no evidence of any and have failed to identify any since then.
And you are clearly out of your depth. I said that the volume of SEDIMENT carried by water flows is in proportion to the square of the velocity, to which all you could come up with was that breathtakingly moronic, “No, its the volume of water which is proportional to the square of the velocity of the flow”. Don’t you think the cross section of the channel might have something to do with water volume as well? And even then, your point is? If you can’t get your tiny brain around that simple hydrological principle then there is little point trying to educate you further.
The fact is you are completely out of your depth. Muttering on about barriers, tossing in your favourite tabloid character assessment simply because you like the sound of it, and adding nothing of scientific merit.
Tony Price says
You’re quite right about proportional to the square of the velocity, in principle that is – I copied a chunk of text I had meant to discard. You managed to continue your insults though, and took more than 2 hundred words to say what a dozen could more concisely and elegantly. I can admit mistakes. You however, being a perfect and infallible being, cannot. You selectively answer, and ignore the rest. You fail to give anyone here any credit for any knowledge or expertise whatever. You really are a toxic bugger, and while I heartily dislike you, I fear for your health. You’re a heart-attack in the making.
Part 2 will follow shortly.
Ian Mott says
Price, you are the object of derision because you have consistently responded with irrelevant bluster and had to be dragged kicking to admit that the relationship between the velocity of water flow and its capacity to carry sediment is as I have consistently claimed.
So how many other vacuous morons on this blog are still contesting this long established engineering fact as if it were some sort of recent fabrication by the climate mafia?
What about you, Hasbeen? Keep in mind that assessments of respect go both ways.
And you, Jennifer? Do you reject this relationship or not? And if not then what is the relationship?
You can’t have it both ways. If you seriously believe the removal of the barrages will allow the tides to scour the mouth and keep it open then you are also contesting the relationship between velocity of flow and sediment load. And it means you are also rejecting the very shape of the tidal curves that have been consistent in the area for more than two centuries.
So stop hiding, Jennifer, and answer these key questions that go to the very heart of your professional competence.
Debbie says
So Peter,
hypothetical question according to your claim that SA has only a 27% influence on MDB infrastructure.
What would happen if Vic with 35% and NSW with 38% decided that it is more economically sensible to just keep dredging the mouth and just open the barrages when there is insufficient inflows to convey enough water to SA to keep those Lakes covered in fresh water?
Remember, it is a hypothetical question, because I do not believe that is the best answer.
I do believe however as Ian points out too, that if SA wants to maintain a fresh water system 100% of the time that is SA’s choice.
Also, the point of the 20% argument is that is not what SA wants. You are not helping your cause by using it. Nobody, including SA, wants the system returned to ‘natural’.
Using environmental arguments and claiming we need to restore the environment above all else is not solving the real problem.
We of course need to be environmentally responsible as we repair and improve our outdated regulatory infrastructure but we’re not doing that because of some notion about a utopian, stable MDB environment. If nothing else, Jennifer has exposed the flaw in that argument.
She, along with many others (including Ian) has pointed out that pretending this process is based on solid, irrefutable science is not achieving any good results. That’s because the science being used is neither the appropriate branch of science to deal with the actual problem we need to solve nor is it being used appropriately because it has been hijacked by misanthropic environmental politics.
The fact that Jen and Ian have a disagreement over the power of tides vs river flows vs barrages etc is further proof of this basic problem.
Did you read the article by Josephine Kelly that John posted?
Doesn’t her main point lie at the bottom of this mess?
The people who have the most to lose and the least resources are the ones who have had ‘the burden of proof’ dumped in their court.
It makes it very easy to ‘divide and conquer’.
Tony Price says
Mott May 3rd, 2012 at 10:16 am: (No first name, the adjective “Christian” implies something or other)
“Price, you are the object of derision because you have consistently responded with irrelevant bluster and had to be dragged kicking to admit that the relationship between the velocity of water flow and its capacity to carry sediment is as I have consistently claimed.”
I said “You’re quite right about proportional to the square of the velocity, in principle that is”
Right as usual of course, what I said clearly involved being “dragged kicking”. It was a mistake, as I knew that you were basically right, though there are many factors involved which you haven’t mentioned. You said I “very conspicuously, failed to provide any means of calculating the volume of sediment”, something you cannot do, and have not done. How can I compete (I didn’t try, just made some observations) as a “vacuous moron”. Careful, you’ll be running out of invective, though it shouldn’t be a problem, as you repeat yourself “ad nauseum” (sic).
The other “vacuous morons” (I’m proud to be one of them if it distances me from you) haven’t challenged you on that. You’re seeing enemies where none exist, and we all know what that mental state is termed.
This is the real part 2. You’re a bully, Mott – I won’t use your first name since you refuse to use mine. You don’t debate, you belittle and insult and move the goalposts constantly. Trying to argue with you is like trying to nail a jelly to the wall.
Mott May 1st, 2012 at 1:36 pm:
“For a guy who accused me of cherry picking, it is quite telling that Tony Price did not respond to my specific invitation to also look at the November tide graphs as a point of comparison to the April ones. Nor did Jennifer, despite the fact that she posted this quote above, ”
So April and November (actually it was October, your selective memory is showing) reflect an entire year? You don’t know whether I looked at October or not. I looked at the entire year, but didn’t bother to comment on it because an analysis of April/May 2012 was sufficient. You said on the other thread:
“Go to http://tides.willyweather.com.au/sa/fleurieu-peninsula/goolwa-beach.html and look at the graphs below the tables. At the graphs go to the calender and go to 13/04/12 and right click the arrow forward for the next few frames and observe the changing patterns. Then go back to the calender and go to 18/10/2011 and right click through to 5/11/2011 and observe the same sort of patterns I referred to.”
Is 18/10/2011 to 5/11/2011 “November”? 13/04/12 and the “next few frames” is NOT 28 days. 18/10/2011 and “right click through to 5/11/2011” is NOT 28 days. Two periods of 20 days and 25 days doesn’t represent a year, nor even 2 complete tidal cycles. The balance between single-tide and distinct 2-tide days varies throughout the year. Some months have more single-tide days, some more 2-tide days, as an annual hourly plot shows.
“Yet here we have Price and Marohasy employing a classic cherry pick to mislead readers into thinking my statements about tides has no basis in fact. So I invite readers to go to Willyweather again and start at May 2011 and right arrow through the entire 12 months to gain an understanding of the whole truth and nothing but.”
So analysing your selective cherry-picked periods is also “cherry-picking? Do you expect everyone to click through 73 5-day frames to get the “whole picture”? That would involve 72 clicks to see the entire year, and you knew knew full well no-one would do it (I’d done it already). You’re looking through a 5-day keyhole at the tide charts, and just seeing what you want to see.
“High tides are normal in Autumn in SA, they’re often known as king tides and they’ll occur usually in April and May each year,” and, “Its not something that is going to persist for very long”.
“King tides” occur from end April through into July. Highest are in end May to end June, and they occur over several days as part of the monthly lunar cycle, not isolated “spikes”
“Note that Price’s focus on total height (in April) is not replicated throughout the year. And he has been very misleading in quoting the height of the main daily inflowing tide without mentioning that the outgoing phase often only goes back to half the amplitude before a small rise leads to a further drop to near the original bottom, depending on the phase.”
Really? Selective memory again, though some would call it something else. I said
“There are two distinct tides, though often of disparate heights for 14 of the 28 days 1st-28th April 2012. Minimum daily tidal range is 0.3m, maximum is 1.1m, peak tide is 1.2m. I’ve estimated MSL as 0.7m which is being generous, and means that peak is at least 0.6m above MSL, and there are 8 other days with identical peaks.”
Is 0.3m half of 0.7m or less? Is quoting max and min daily tidal range just “quoting the height of the main daily inflowing tide without mentioning that the outgoing phase often only goes back to half the amplitude”?
You said “There is generally only one tide each day, and that is only during the 50% of the lunar cycle when they even take place at all. And, aside from storm surges, they only exhibit a tidal range greater than 70cm on 4 or 5 days each month.”
So let’s look at a month, your month of April 2012 in this combined chart of 29 days, to encompass a full lunar cycle:
https://lh4.googleusercontent.com/-kJ2My_OWzbU/T6GtOUqlc9I/AAAAAAAAAyM/xR1oG9q12QQ/I/Victor%252520Harbor%25252C%252520SA_April%2525202012%252520tides.gif
To remind everyone, 70cm is a little less than 1.5 vertical divisions. Count Ian’s “4 or 5 days a month” – I make it 12. Check out the “50% of the lunar cycle when they (tides) even take place at all”. The other 50% seems to be varying up and down quite well, though rather less. The BoM rates that part of the coast as having a tidal range of 125cm.
http://www.bom.gov.au/oceanography/tides/MAPS/sagulf_range.shtml
Here’s a chart for Victor Harbor from 2000-2010 (monthly, latest data available)
https://lh5.googleusercontent.com/-hZ7IyA01JQ0/T6EJZqPR-uI/AAAAAAAAAx0/PmMbDy58Xl0/I/Victor%252520Harbor%25252C%252520SA_2000-2010%252520monthly.gif
The max and min are each just one reading for the month, so the range is rather less than the 150+ suggested by those plots, and chimes with the BoM range figure of 125cm.
Check out also Portland, VIC, which I used as a model for Victor Harbor, so I could plot hourly data.
http://tides.willyweather.com.au/vic/western-district/portland-harbour.html
… and compare ANY 5-day period with that for Victor Harbor to see the almost identical tidal envelope.
http://tides.willyweather.com.au/sa/fleurieu-peninsula/goolwa-beach.html
… except that the latter has higher peaks, which justifies my use of Portland as a proxy for Victor Harbor hourly data.
Some of you might care to check out the links for enlightenment. I know one who won’t. He doesn’t need to, He is the fount of all knowledge.
I didn’t focus on April YOU did. How could I? I wasn’t even aware of the WillyWeather site, and I responded with a summary of tidal patterns over the 28-day lunar cycle which show that your claims are delusional. You pointed readers to periods in April 2012 and October 2011. The tides have both a monthly and an annual cycle. To get the whole picture it’s necessary to look at a whole year MINIMUM. Looking at 2 months in 12 is cherry-picking, by any standards. It’s another bully tactic, accusing your opponent of doing what you’ve been doing.
“It is, after all the amplitude of the daily tidal range that determines the volume of water in each tidal flow, which in turn determines the velocity of that flow, which then determines the volume of sediment that is moved by that flow.”
Does a high amplitude (range) but relatively low peak tide “determine the volume of water”? Can a 6-foot man see over an 8-foot wall when he’s standing on the bottom rung of a ladder a foot off the ground? Can you see anything through your selective 5-day keyhole?
I’ll put all the charts and graphic into a blog page so they’ll be easier to scan and compare with what’s been said (and claimed) here. Link to follow.
To all vacuous morons (I want the t-shirt) everywhere, goodnight, and don’t elect any politicians who make very specific promises while I’m away. I’ve got enough to blog on as it is.
jennifer says
Tony
I look forward to the blog post where you put all the charts and graphics in a format where its easy to scan and compare what has been said.
But an issue that I think both you and Mott are ignoring is that the really big waves associated with storm events remove significant volumes of sand. That is evident from a general reading of the literature associated with the Lower Murray.
In short, it would seem that day to day there is mostly an accumulation of sand from wave action, but that big waves associated with storms drag that same sand back out to ocean. Also big flood events also push sand out to the ocean (or used to before the barrages and would be much more effective at the same if channelled e.g. down the Mundoo channel).
As with so much to do with the Australian landscape, the extreme events of short duration are critical to understanding the system but too often ignored.
Anyway, look forward to your blog post.
Ian Mott says
Tony Price’s very first post at the previous article made it clear that he was going to troll through my posts looking for the “potential inconsistencies” that he had already claimed to be there but had not identified. He copped a serve because it was already clear that he had no intention of making a balanced assessment.
And that is exactly what he has done since. He would take a general statement of mine, which was necessarily not 100% correct due to the competing need for brevity and prance about as if he were Mussolini on a viagra holiday. And for what? A vain attempt to stooge people into believing that the difference between the low tide and the high tide determined the volume and velocity of the inflow and the eventual outflow. Note that he doesn’t actually refute this fact, merely serving up an infantile analogy about 6ft men behind 8ft walls.
And by the time he has arrived at his last post above the only thing missing from his diatribe is the spittle. Note also that he has not made a single comment about the majority of my position, that the claimed “savings” of fresh water evaporation from the lake have minimal basis in fact.
More importantly, Jennifer has again refused to make any statement about whether she accepts or rejects the fundamental relationship between flow velocity and sediment load. Why, Jennifer?
And for the record, I gave the April tide charts because, at the time, it was still April and I gave the October/November charts because it was half a year later than April/May. But the fact that Price is now so over-the-top on minor irrelevancies like refering to November only when some October data was included only highlights his pathetic search to mention anything but the matters of substance.
And his accusations that I will not admit to error are even more off the mark. This very blog has numerous instances where I had previously made clear that I supported Jennifers position on the barrages. In fact, it is my recollection that I called for their removal before she actually did. But it is also a matter of public record that my 2010/11 submission to the MDBA included a clear admission that my previous position was based on ignorance of the fundamental hydrodynamics at play. When faced with new evidence that contradicted my past opinion I admitted my errors and altered my conclusions.
It is also a matter of record that Jennifer, when advised of the additional evidence, not only ignored it like she has done on this thread, she went out of her way to disparage my conclusions in a way that carefully avoided any form of substantiation.
Denis Webb says
Who would have thought that the scoundrel Mr Mott might fear an audit by Mr Price? Bring it on.
As regards Dr Marohasy, she demolished Mr Mott over at the Just Grounds Community blog some months ago.
Looking forward to seeing it all again courtesy of Mr Price.
Tony Price says
“And by the time he has arrived at his last post above the only thing missing from his diatribe is the spittle. Note also that he has not made a single comment about the majority of my position, that the claimed “savings” of fresh water evaporation from the lake have minimal basis in fact.”
Why should I be forced to take a position on something I know little about? I know nothing about most things (like most people), I know a little about some things (like most people), I know a fair bit about a few things (like most people). I know a lot about sea level, and temperatures, and physics, and chemistry, and computers, though only a fraction of what there is to know. I can put that knowledge, and the means to expand on it on the ‘net, to good use skewering alarmists, apologists, and also so-called sceptics who deny (no better word for it) the laws of physics, draw consequently flawed conclusions, and beat everyone in reach (worldwide with the ‘net) over the head with their “new truth”. Doug Cotton (new mercifully totally engaged by the total heroes over at tallblokes and out of our faces) is an extreme example.
I didn’t think I’d see his like here. I’m not suggesting for one moment that Ian’s denying any kind of science, but he’s exhibiting the same kind of “believe me, I know, and the rest of you are ignorant bludgers if you can’t or won’t agree totally with me” stance.
Ian’s (I’ll use his first name again as he seems to have calmed down a bit to something approaching his normal acerbic and derogatory style) general technique is to make unsupported statements of opinion, lace it with a lot of impressive though unreferenced statistics (blinding with statistics), use lots of technical terms like “tidal prism” which most here are unfamiliar with (blinding with science), draw tenuous conclusions which bear little examination, and beat off any challenge with diatribe and bluster.
I stumbled upon a post Ian made here in 2006 while doing an unrelated Google search – I hadn’t realised he’d been that involved here. I pay little attention to blog sidebars so I didn’t see the Author’s list on the left, or if I did I ignored it. Reading through some of his posts, and his replies, I began seeing logical or factual flaws in several posts, and found myself at least sympathising, in several cases agreeing, with comments from Luke of all people (amongst others). Here’s an example from 5 years ago:
Comment from: Luke January 28th, 2007 at 4:08 pm
Readers will note Ian’s typical groin-kick style as way of saying hello. Readers might also note this is why Ian doesn’t do well in discussions with guvmint anymore as extreme rudeness doesn’t make a good basis for discussions. Although some people are probably immune by now. Instead of doing the nana coz you know I’v made some reasonable points try a discussion for a change.
http://jennifermarohasy.com/?p=846&cp=1#comment-22014
On one post, Ian challenged someone who disagreed with his statement (no citation nor links) on the impact of temperature extremes on fauna to produce a list of threatened species! Sound familiar? Here’s what he said above “You plucked your understanding of sediment transportation out of your own backside and, very conspicuously, failed to provide any means of calculating the volume of sediment”. I haven’t got the means, as he said, but NEITHER HAS HE. It would take a lengthy and costly survey of tides at the mouth, water levels within, likely satellite images also, and a flow and transportation model to do that. Ian maintains it’s simple and keeps shouting “it’s the square of the velocity, stupid!”. What velocity, Ian?
He pointed out I didn’t know the cross-sectional area of the mouth wrt flow. I don’t know, I didn’t know, I didn’t claim to know, I didn’t NEED to know. NEITHER DOES HE KNOW. He claimed to know exactly what the tidal profile at the mouth was by scanning through a few 5-day frames at WillyWeather, then invited others to do the same, to “prove his point”. No-one can know what that profile is without analysing (not just squinting at) an absolute minimum of a years tidal data, preferably many years, and not just peering at a few 5-day frames at WillyWeather. His “4 or 5 days a month” doesn’t hold any water, his “mostly single tides” doesn’t hold any water, his “50% of the time” doesn’t hold any water. The only thing which holds any water is the barrages, and they’re saying nowt.
That gets me back to my point. I don’t need to know anything at all about Australia, the Murray-Darling Basin, the history of the barrages, river flows, estimates of evaporation and rainfall, or the colour of Julia Gillard’s hair to challenge him on tides and sea-level, and make (informed or otherwise) observations on his posts and comments. It’s his prerogative to challenge me on anything I say, and it’s my prerogative to present evidence in rebuttal. It’s therefore incumbent on him to examine that evidence and not to rubbish it without examination, as he’s done so far.
I work with facts and data, cite sources for them or provide charts or images. I graph data and count things and don’t make assumptions based on opinion alone. I don’t constant;y insult or belittle others, but read what they say, analyse and respond. I’m gentle with the uninformed, and brusque with the blusterers. I can learn from anyone “be he ne’er so base” (Henry V), and like that king’s faithful followers, am eager for the fray. “Once more unto the Mouth, dear friends! Once more!” One novice or casual visitor who is made to think and research rather than simply state opinions is worth a dozen “experts” who refuse to.
I like this blog, which means I like the people who present it, who frequent it, who express opinions, who learn from others, who’ll admit when they’re wrong, who don’t try to force their opinions down others throats, who can use humour and appreciate humour, and take a little gentle ribbing, whose mere presence adds spice to the debate. I hope I’m seen as one of them, of you. I’m even beginning to understand Luke better, and realise his apparently dismissive and combative tone is as much a reaction to his treatment by a person or persons who shall remain nameless as any inbuilt attitude problem.
BTW – completely off-topic, but did anyone actually look at my chart of sea-level at Victor Harbor? The 2000-2010 trend is flat, totally flat, zero, zilch. It’s a gauge the CSIRO ignores of course, for them the only way is UP (except for rainfall and the Great Barrier Reef. It’s DOOMED I tell you, DOOMED!).
Tony Price says
I was going to post a critique of one of Ian’s Posts here, but this takes the biscuit:
“Tony Price’s very first post at the previous article made it clear that he was going to troll through my posts looking for the “potential inconsistencies” that he had already claimed to be there but had not identified. He copped a serve because it was already clear that he had no intention of making a balanced assessment.
And that is exactly what he has done since. He would take a general statement of mine, which was necessarily not 100% correct due to the competing need for brevity and prance about as if he were Mussolini on a viagra holiday. And for what? A vain attempt to stooge people into believing that the difference between the low tide and the high tide determined the volume and velocity of the inflow and the eventual outflow. Note that he doesn’t actually refute this fact, merely serving up an infantile analogy about 6ft men behind 8ft walls.”
“He would take a general statement of mine, which was necessarily not 100% correct due to the competing need for brevity” what? WHAT? Not 100% correct because of the need for brevity? A “general statement” which is not correct? You admit to making statements “not 100% correct”, and blame the need for brevity? You say that someone who picks you up on such a statement should be allowing you leeway because you cant condense words into correct statements? You have a serious mental condition – you need help.
You then say I was trying to “stooge people” into believing something you then say is a fact which I can’t refute? How can I refute something and try to convince people it’s true at the same time? You’re mad – you can’t even read and understand what you’ve written.You’re thrashing about in denial and confusion. Can’t take the heat of criticism, constructive or otherwise? You’re also a 100% liar Mott, plain and simple – I was able to overcome the need for brevity and make a 100% correct statement there.
Tony Price says
Jennifer said:
But an issue that I think both you and Mott are ignoring is that the really big waves associated with storm events remove significant volumes of sand. That is evident from a general reading of the literature associated with the Lower Murray.
No, I’m not ignoring it, I’ve put it on one side. Such events are easily identifiable in the tidal record, they have a signature, if you know what to look for. Remember Ian was claiming I was confusing high tides with storm surges when counting peak events to refute his “x times a month” theme. Ian assumes storm surge effects have only the effect of depositing sand, whereas you know the truth, that they often leave a beach denuded of sand, or can remove large net quantities from the Murray mouth, especially if heavy rain has softened or even liquefied the sand inside. Such events are of course infrequent but important.
Ian is myopic, and he’s now stooping to accuse me of what he’s guilty of, and making excuses for incorrect statements made “because of the competing need for brevity”. Yes, really – you should read his post before this one.
Peter R. Smith – OAM - Mannum says
Hi Debbie,
My percentage figures are not a false claim they are figures from MDBA via David Dreverman!
I don’t know, “What would happen if Vic with 35% and NSW with 38% decided that it is more economically sensible to just keep dredging the mouth and just open the barrages when there is insufficient inflows to convey enough water to SA to keep those Lakes covered in fresh water?” but I would have thought the agreement was robust enough so that could not happen.
And Ian is correct, “I do believe however as Ian points out too, that if SA wants to maintain a fresh water system 100% of the time that is SA’s choice” but once again, “I would have thought the agreement was robust enough so that could not happen.
I am the first to agree, “We of course need to be environmentally responsible as we repair and improve our outdated regulatory infrastructure but we’re not doing that because of some notion about a utopian, stable MDB environment. If nothing else, Jennifer has exposed the flaw in that argument” but as for Jen, exposing the flaw the flaw she her opinion!
Yes I, “Did you read the article by Josephine Kelly that John posted?”
Hi Tony Price,
Re, “Why should I be forced to take a position on something I know little about?” is that not a good reason to butt out of the Barrages either staying or being removed debate?
Tony Price says
Some thoughts on one of Mr. Mott’s posts I would have posted earlier:
“So much Murray River flow and so little to show for it.
The alternatives to fresh water for both tasks are far more effective and come at a fraction of the cost. Just one large, unidirectional, 1km pipe under the dunes, of the same 6.4m diameter as the 22km Tumut-Eucumbene tunnel that was cut through solid rock, would passively on each high tide, deliver more than a million ML of fully oxygenated sea water a year to the South Lagoon. This would flow north to the Murray mouth, completely flushing the entire Coorong four times a year and returning that entire system to habitat values and water quality that it would only have experienced briefly in the past 10 millennia.”
http://regionalstates.wordpress.com/2011/12/15/so-much-murray-river-flow-and-so-little-to-show-for-it/
Pipes. A big pipe for the Snowy River, four pipes for the Murray mouth, one biggie for the South Lagoon. All we need is pipes, but let’s not be negative, there’s more to pipes than meets the eye, as we shall see. “On each high tide, deliver….” – rather depends on the height of the tide and the height of the water inside the lagoon, methinks. The height inside would tend to build, reducing inflow, as we’ve been told often enough that outflow (through the mouth) is reduced by the asymmetric shape of the tidal profile, and as we’ve also been told, there are barely any tides at all for 2 weeks in the 4-week lunar month.
“Flow north to the Murray Mouth” would needs be rather slow over the 50km distance, unless the tides are bribed to stay outside the mouth, and not flow through the mouth and the newly installed one-way pipes there. Four pipes and the mouth to the north, one pipe in the south. Which will predominate I wonder? The sensible multi-pipe approach would seem to me to leave the lagoon pipe open as the tide falls, so a mixture of fresh and salt water is drawn from the north into the Coorong, but then, what do I know? I’m just a vacuous moron.
“Two more pipes on either side of the Murray mouth, with ocean intakes above the sea floor, will ensure that half of each tidal inflow gets inside the mouth without bringing any sand with it. And by blocking the pipes on the outflow the total volume will then flow out the mouth, taking the sand with it.”
Er, no, not quite – the floor of the mouth is a sandbar, with deeper water each side. Sand is heavier than water, as any child on a beach knows, so the sand coming through the mouth is deposited inside the mouth in deeper water, and as we’ve been told “ad nauseum” (sic), the outflow is slower and over a longer period than inflow. Unless sand can be driven uphill by the much slower outflow, it will still accumulate inside, though to a lesser extent because of the sand-free pipe inflow, if such a thing is possible. What’s been missed here is that the pipe inflow will build up the level inside the mouth much faster than before, and inflow through the mouth will be reduced. Less inflow, slower velocity, less sand brought in. Right result, partially wrong reasoning.
Two minor observations on accuracy :
“And this is on top of the above mentioned 5 million ML of long term average annual discharge into the sea, which obviously flows 100% of the river length, delivering ecological benefits to every mile it flows through.”
Delivering floods in every mile of the upper reaches too, if that volume “obviously flows 100% of the river length”.
“Furthermore, the other two weeks in every four have a very modest tidal range and this produces much less sand deposition to be corrected. So half of each cubic kilometer that flowed out to sea in 2011 was wasted because there was no sand deposition to be counteracted while that outflow took place.”
Note that “much less sand deposition” immediately becomes “no sand deposition”. The “Riddle of the Sands” indeed.
I can’t comment on the statistics in the post, as there are no references whatsoever, and I’m not prepared to do someone else’s work for them, Googling for hours to check their validity or at least provenance. Perhaps that’s what’s intended, but if not it’s a very lazy and unsatisfactory way to blog. What might be perfectly valid comes across as mere opinion. At least Luke provides copious links and quotes in his comments. He’s striving to change peoples’ minds by making them read more widely and think for themselves, and while I disagree with much of what he says, I can’t fault his technique, most of the time anyway.
I apologise in advance if I happen to have made any incorrect statements due to the competing need for brevity. That’s what Ian admits to above, so what’s sauce for the goose…..
Debbie says
Peter,
I did not say the % figs were false.
Why do you keep accusing people of saying things they did not say?
It leads you to answering the wrong question and then asking further irrelevant questions.
If you can’t or don’t want to answer questions then that’s your call, but please cease pretending that you are.
Tony Price says
Some observations on:
Barrages and Murray Mouth Mirages
http://regionalstates.wordpress.com/2012/04/17/barrages-and-murray-mouth-mirages/
“And just like the climate mafia MO, legitimate critique is dismissed as ‘junk science’ and the work of ill-informed opinionators with an axe to grind.”
Sound familiar to you? The, calling, kettle, black, the, pot – rearrange to make a well-known phrase or saying.
“Interestingly, there is a wide range of conversion rates from pan evaporation in the literature. The Coorong, Lower Lakes and Murray Mouth Long Term Plan, Appendix 3 appears to have adjusted Pan to Actual evaporation by a factor of 0.92 while The MDBA’s modeling for end of system flows (Heneker 2010) uses 0.85.”
Ian earlier used “about 20% less” which is 0.8. ‘Nuff said.
“But note that net evaporation would only produce a significant reduction in lake volume if there was zero flow in the Murray River over a full 12 months interval. And it would only be at the end of that 12 months that the cumulative 685,500ML shortfall allowed the same volume of sea water to enter the open lake.”
The first sentence is plainly nonsense. There would be a reduction in lake volume if the inflow was less than the evaporation, it need not be zero. Why need it be over a “full 12 months interval”, when most evaporation and low river flow occurs in the dry season, which would produce most of the effect?
Sea water would only enter “at the end of that 12 months”? Would the tides wait outside the mouth clutching a calendar?
“But they fail to appreciate that perfectly good fresh water that mixes with sea water and flows out to sea is just as ‘wasted’ as fresh water that is evaporated. And none of either type will amount to any benefit to up-stream irrigators”
How on earth could lake water or evaporation ever be of any “benefit to up-stream irrigators”? A canard, an irrelevancy.
“They have also failed to explain how this mixing might take place through the narrow entrance to Lake Albert”
Virtually nothing goes through that entrance now, nor would it with the barrages removed. Why should “they” even mention it, let alone explain it? This is Introducing yet another irrelevancy to give the impression of scoring points.
“It should not be forgotten that this “up to 1 million megalitres” claim implies that it will be saved each year. But when we deduct the mean annual rainfall figure from the actual evaporation it should also be obvious to most that 590,660ML average evaporation can be completely negated by a river flow of the same modest volume. As long as the river flow is greater than the evaporation shortfall there is minimal scope for a permanent transfer of sea water into the lakes because the fresh water continues to push the sea water back. But the fuzzy logic of the AEF appears to have a problem with the fact that the sea water that comes in on the few high tides each month that exceed 70cm amplitude is the same stuff that goes back out six hours later, leaving the fresh water exactly where it was earlier.”
No it doesn’t imply it, it’s an annual estimate. Doh! This doesn’t even begin to address the seemingly valid point that if the river were dammed or locked just above the outflow point into the lake, it’d be sea water that would be evaporating, and virtually ALL the river water would be available for use. Avoid the issue and liberally apply bluster – impresses some, but not me, and not Jennifer and her supporters. I have a sensitive bullshit detector, and it’s reading full scale.
The “fuzzy logic” of the AEF tells them that if any sea water comes in on the 8 to 12 (I counted ’em over 12 months) tides which are sufficiently high (well-nigh irrelevant “amplitude” cited here again) to cause incursion, some mixing will occur, so the fresh water may be back “where it was earlier” but well seasoned. Their “fuzzy logic” also tells them (and me, but not you, you’re doing your little Mott-step sidestep again) that there wouldn’t be any effect of mixing if the lakes were already sea water, other than the incoming sea water being less polluted and well oxygenated.
“the sea water that comes in on the few high tides each month that exceed 70cm amplitude is the same stuff that goes back out six hours later” – that same, easily refuted 70cm again. Six hours later? That means the tides are asymmetrical in profile, but shallow in, steep out. I thought he said elsewhere that typical tides were asymmetrical and steep so fast in, shallow so slow out – remember?
“When I explained that there can be no significant transfers of sea water while river flows were anything more than very modest, Ms Marohasy then asserted that significant intrusions could still take place during the low-flow half of the year.”
She said “could”? Then she’s right. you’re so in love with your 5-day window on the tides, you’ve never seen a full annual picture. There are tides of well over 50cm above MSL over the entire year, though fewer in late February/early March. 50cm means they exceed your myopic 70cm range by up to 30cm, sometimes more, often for 4 or 5 days at a time, twice a month. Do you understand that? Up to means “as much as”. The AEF’s “disturbingly vague, ‘up to 1 million megalitres a year” according to you, means “as much as….”.
“SALE – up to 50% off” is well understood by billions, yet you would find it “disturbingly vague”. You’re missing out on some real bargains, mate.
“From May to September in an average year local rain falling on the lakes themselves actually exceeds evaporation from them to produce a net outflow independent of interstate river flows. This period also coincides with maximum run-off from local creeks that drain into the lakes. The combined outcome is substantially diminished capacity to accommodate tidal inflow at the very time when Ms Marohasy claims such inflows will be greatest.”
King Tides, Ian, King Tides, much higher than the level inside the mouth in the first few months of that period – you brought it it up here. You said April/May when it’s usually late April to end June or early July. The tide charts at Willy Weather show them over that period, the sea-level chart for Victor Harbor shows them over that period, every year, year in, year out, varying of course, but always evident, and always BIG.
“This was not the case before the major storages were built. The annual melt water previously flowed quickly to the mouth and was colder than the sea water and produced much greater mixing with that denser sea water.”
This is called “making it up”. “Quickly to the mouth”? From where? How far? Into huge warmer lakes and out at the narrow seaward end well-mixed after days at least?. Perhaps the cold dense meltwater floated across the top of the warmer less-dense lake water? Fresh water at any temperature is much less dense than sea water, It’ll always stay on top.The density of fresh water can only exceed 1 by a tiny amount. Sea water is typically about 1.03 over a range from 10 to 25°C.
http://www.csgnetwork.com/h2odenscalc.html
“The AEF have consistently refused to accept the fundamental scientific reality that the capacity of flowing water to shift sediment is determined by the square of the flow velocity. At most times the inflowing tides take 8 hours while the outflow takes 16 hours and that means the inflowing tides, in the absence of river flows, deposit four times more sediment than the outflow can remove.”
He’s done my work for me! Remember that “stuff that goes back out six hours later” above? Have they “refused to accept”? Is this a “straw man” I see before me?
“An equilibrium of sediment movement is only achieved when river flows are sufficient to double the volume of outflows so the velocities of both flows are matched. Prior to irrigation allocations this was usually the case but since then it has become a less frequent norm. The barrages have been a very useful response to this by substantially reducing the size of the tidal prism so both tidal inflow volume and velocity have also declined and sand deposition has declined with it.”
I don’t understand that first sentence at all. Must have meant “inflows” not “outflows”. A tiny error introduced by the conflicting need for brevity? The barrages also ensure any sand is deposited close to the mouth and is not swept much further in, and therefore spread more thinly.
“sand deposition has declined with it.”, which is why the mouth has needed extensive dredging? Have a look at the mouth here (click to enlarge): http://blog.carbontalks.ca/archives/574
Sure looks like sand to me, lots of it, and mostly inside too. Also looks as though the sea needs rather more than a 70cm leg-up to get over that sand obstacle.
jennifer says
Thanks for all of this Tony. I hope a few of the people who email me thinking Mott actually has a rational argument read it.
I hope they at least come away from this thread acknowledging that there are some big tides, king tides.
Also, unfortunately I don’t think many people have much of a concept of just how “huge and warm” those lakes are.
I’m not even sure if Mott has ever been down and seen how vast they are.
I do get the impression many are UNAWARE that river flow needs to make it across a vast shallow evaporation basin, then through concrete barrages, before it can push any sand out the mouth.
Debbie says
Yes Jen,
That’s the bit that’s confusing me.
I don’t pretend to know much about the tides there but I do understand the rivers in the Southern MDB.
Except on intermittent occaisions, the Murray River is not capable of doing that.
If it was like the Amazon or some of the glacial fed rivers in Europe, then maybe it could…but it isn’t…never has been and never likely to be…..there would need to be seriously major engineering works installed to make it behave that way.
Also, if the river was able to do that with any regular consistency, then the area under discussion would look more like a delta wouldn’t it?… rather than what has naturally formed there pre and post river regulation?
Ian Mott says
Gosh, so much verbage from Tony Price and so little of substance. Rest assured, readers, whenever someone does such a massive dump on a blog thread it is because they are attempting to distract attention from something else. And in this case it is to divert attention from the fact that Jennifer has still avoided making any comment on her acceptance or rejection of the long held engineering/hydrological principle that the velocity of a water flow determins the volume of sediment it can carry. Why are we still waiting Jennifer?
Readers will also note that Price is so determined to find fault that he has now taken issue with the fact that a summary conveys less information than a detailed statement. He doesn’t appear to have the same problem with even greater and far more material inaccuracies in Jennifer’s statements, or his own, but the leering glee with which he jumps on my own quite willing admission that summaries are less accurate than detailed statements tells us much more about himself than anything else.
His claim that pipes under the dunes won’t work is more evidence that his eagerness to find fault has overtaken his reason. If he had bothered to go to the actual submission that was cited in the article he would have known that it was this formal document that contained all the relevant references that he accused me of not supplying. Those references include all the reports that conclude that local tides are asymetrical and that storm surges deposit sand rather than take it away.
And his claim that the pipes won’t work is based on the absurd notion that the pipes could only be located so close to the mouth that the existing deposited sand would impede their discharge. The reality is that there are a few km of channel in either direction where the pipes could be located without the problem he manufactured entirely for his own ends.
Ditto for the pipe to the south lagoon. This crazed nutter chose not to grasp the simple fact that, given that the level of the south lagoon is stable at or just below AHD, passive inflows can only take place during the upper half of the tides and as the inflows would eventually raise the level of the lagoon to produce a slow northerly discharge.
And then he even goes so far as to deny the simple fact that water that flows down the Murray delivers ecological services to the river as it flows. I never stated that all flows produce floods but he needed to extrapolate to the absurd to try and win a point.
Balanced readers will by now be recognising the rantings of a desperado who is so eager to defend his preconceptions that he is willing to quote the sequence of departmental goons who have operated the “Luke Desk” in Qld DNR/EPA to post on this blog.
Meanwhile, back at the key issue. Does Jennifer accept or reject the well established and hitherto unchallenged engineering/hydrological principle that the volume of sediment borne by water flows is determined by the square of the velocity of flow. Our raving mate Price has already accepted this principle but Jennifer has not/
Price’s blather about being unable to calculate actual flows and actual volumes completely misses the point. All we need to know is that for any given tide volume, through any given mouth dimensions, an inflow that takes half the time as the outflow will flow at twice the speed of the outflow and will therefore deposit 4 times the volume of sediment that the outflow can remove. The important factor is the comparison of the two flows based on the slopes of the tide graphs.
Reasonable men and women have no trouble understanding that the speed of inflows are not always twice the speed of outflows. Indeed, they would rarely present such a neat equation. But the evidence of tidal asymetry is overwhelming from any observation of the annual sequence of tidal graphs and is uncontested in the credible literature.
So what about Jennifer? Does she reject this conclusion as well?
Susan says
Enjoyed reading your posts Tony.
Tony Price says
I’ve posted a rather nice and very big picture of The Murray mouth, a handy map of the barrages, and my own sea-level and tidal charts here:
http://mostlyharmless-room-101.blogspot.com/2012/05/australia-murray-mouth-effect-of-tides.html
I’ll be adding to it later.
Debbie says
From today’s weekly report…..
At the Lower Lakes, all Barrage gates at Goolwa and Mundoo were closed for two days to minimise saline incursions during a large swell event over the weekend. This resulted in a rise in water level of 19 cm at the Goolwa Barrage gauge but a much smaller rise in the average level across all Lower Lakes gauges. The level has since declined slightly after the gates were re-opened. At Tauwitchere and Ewe Island Barrages, 137 gates remain open to enable the passage of the current high inflows that continue at the Lower Lakes.
The 5 day average level for the lakes is 0.76 m AHD or 1 cm above full supply. Renewed high tides with levels up to 1.46 m are forecast for the coming week. To prevent short periods of reverse flow, the gates at Goolwa and Mundoo will be closed for much of the coming week. High water levels in the Lower Lakes are therefore expected by week’s end. These operations are being adaptively managed, for although tide heights can be reasonably well predicted in advance, the impact of winds and swells on tidal surge are more difficult to predict.
Tony Price says
Mott is thrashing about treading water in a vain attempt to stay afloat. He can’t and doesn’t recognise that anyone else might have a valid viewpoint. He contradicts himself in his posts and his comments here and appeals to your joint mercy. If he’d actually read what I’d wrote and engaged his brain before before he put fingers to keyboard he’d have realised that I didn’t say the pipes wouldn’t work, just the opposite. It’s not necessarily the best or cheapest solution but it has merit and should not be dismissed out of hand. I didn’t do so, but he sees enemies under the bed and dastardly criticism in every statement, or at least those he bothers to read and understand. He pigeon-holes people and what they write, and that leads to misunderstanding and exposing himself to ridicule.
He challenged me to put up or shut up on my promise to give his blog posts a good lookover, and doesn’t like the outcome. Tough luck. Does he expect every reader to roll over muttering “a masterpiece!”? His ego’s taken a knock, and he doesn’t like it because he’s not used to it. This is the real world out here Ian, and by blogging and writing submissions you expose yourself to detailed analysis and criticism. It you can’t take the heat….
What would most people (Ian is not “most people” btw) deduce from “All we need is pipes, but let’s not be negative, there’s more to pipes than meets the eye, as we shall see.” and “The sensible multi-pipe approach would seem to me to leave the lagoon pipe open as the tide falls, so a mixture of fresh and salt water is drawn from the north into the Coorong,”. If I was saying as he claims that the pipes wouldn’t work I could hardly use the words “sensible multi-pipe approach” in any context.
“If he had bothered to go to the actual submission that was cited in the article he would have known that it was this formal document that contained all the relevant references that he accused me of not supplying.
I’ve posted”
I have it, I’ve read it, and I’ve seen the references, and they’re comprehensive. My point was that most people won’t download the pdf, but will move on. A few key references at the bottom, or inline links as is usual with published abstracts of scientific papers is all that’s necessary. “It’s all in here” forces people to read it, and most will move on uneducated and unimpressed, or worse, get entirely the wrong impression, as I did initially. I only persevered because I’d said I would.
Your submission is quite professional, your blog posts are amateurish and bordering on a rant. Why do you do it? You have a perfectly valid argument, whether I or Jennifer or anyone else agree with you or not. You mess the whole thing up by being pig-headed about things like tidal range, supposition about many aspects of water movement and so on, and STATISTICS. You have no clarity nor brevity, and that leads to silly errors, which is why you open yourself to detailed criticism.
You could have said what you had to say in far fewer words and got your message over far better, especially if you’d refrained from rubbishing the opposition. You gave a link to your submission – summarise the arguments, point out what you say are errors and inconsistencies in contrary arguments, and move on. Simple statements of your and their positions and claims while leaving the reader to judge is best. You’re in love with statistics and quantities, and expect others to be impressed by them.
Statistics support arguments, they don’t make them.
Comment from: Peter R. Smith – OAM – Mannum May 4th, 2012 at 4:16 am
Hi Tony Price,
Re, “Why should I be forced to take a position on something I know little about?” is that not a good reason to butt out of the Barrages either staying or being removed debate?
He was referring to evaporation estimates. If I knew, or thought I knew little about the overall situation and issues I’d not be typing this right now. I could discuss aspects of the prison system without being forced to take a position on corporal punishment. I could discuss the pros and cons of owning an Audi without being forced to say whether it’s better than a Merc. Why can’t I discuss the aspects of the Murray Basin without knowing if evaporation estimates are correct or not? There are many general principles and key points under discussion, no-one should be forced to discuss and form an opinion on every one. You and Mott are being unreasonable and churlish, or perhaps you just misunderstood what he said and what I meant, in which case I apologise.
Tony Price says
“what I’d wrote” – just spotted it. I meant of course “what I wrote” or “what I’d writt”. Or something.
Ian Mott says
Now I have heard it all. This verbose boofhead has the gall to claim that I could have said it all in a lot fewer words. And nice try at a sidestep, you clearly claimed that the deposition at the mouth would impair the flow but when the stupidity of your claim was exposed you took off to the other end of the Coorong.
The most pathetic part of your spleen dumps is the fact that you manufacture your own spin on what I have said, place it out of context, and then show us what a clever dude you are by demolishing your own invention. Your little wank about the cold melt water is a very good example and reveals all your attempts to portray yourself as an impartial critic for the sham they are. Snow melt used to take 30 – 40 days to flow the length of the Murray but these days it gets to spend the summer in the Hume Dam where it warms up before being released. Simple stuff but you couldn’t help yourself from inventing your own absurdity so you could then ridicule it. Pathetic.
And after your performance on this thread I am surprised that you would even know what a professional submission looks like. From anyone else I would have thanked them for the compliment but a compliment from a scrubber like yourself would have to be the kiss of death.
And while you may not understand how river water can balance sediment flows and offset the effect of the asymetrical tides, resonable men and women without a retention deficit will have no such problem. It is very simple folks (no wait, you are the expert Price, how about you and Jennifer get together over the weekend and explain it to your punters). I’m off to the farm for 3 days so you’ll have plenty of time to work it all out. And then we’ll see what sort of experts you really are.
Still no word from Jennifer on her very own remake of the fundamentals of sediment loads in water flows. Is she finally trying to get herself up to speed or is she just making it up as she goes along?
jennifer says
Tony
Brilliant aerial shot of the Murray’s mouth at your most recent blog post showing so much sand:
http://mostlyharmless-room-101.blogspot.com.au/2012/05/australia-murray-mouth-effect-of-tides.html
And as per my comment at your post, I’m still puzzling over the two very uneven tides.
Much thanks, and cheers,
Tony Price says
Yes, Jennifer – what a magnificent pic! But its’ not just a picture, it’s evidence also. It shows that what I said about the Murray mouth forming a raised “sandbar” is accurate. Maps imply it, logic dictates it, but that picture shows it. The incoming tides dump sand over the bar which any outgoing flow cannot remove entirely. There’s deeper water towards the Coorong SW of the mouth, and there’s deeper water off the bottom left NW towards Goolwa (clearly visible on Google Maps/Earth).
Ian’s picture is too simplistic; water coming in over the bar brings sand with it; an amount of sand which depends on wave action and consequent turbulence, speed of flow, and direction of wind which can have an enormous modifying effect on both. Turbulence increases the amount of sand pulled or thrown into suspension by the incoming tide; that amount will be much in excess of that calculated from flow velocity alone. The stronger the wind, the higher and more frequent the waves, the more turbulence results, the more sand is picked up by the water to be carried onto the beaches or more importantly over the bar to be dumped on the edges of the growing “inflow delta” evident in maps and photographs, and beyond. But not far beyond – the picture also shows that clearly too.
If the wind is from the SW, it will drive sea water towards the mouth and the two peninsulae either side, amplifying a rising tide, holding back an ebbing tide. The curving-in “shoulders” either side of the mouth will have a focussing effect, as in a river estuary but obviously much less, and provide further amplification.
Tides at Victor Harbor have a greater range (seen mostly in the higher peaks) than further along the coast to the SSE towards Portland. The peninsula on which Victor Harbor sits, and Kangaroo Island both block and focus the rising tide towards the peninsula. The effect at the mouth to the east would be similar though rather less, so the Victor Harbor gauge is a good indication of what’s happening the mouth but exaggerates it a little.
A NE wind will obviously have the exact opposite effect. NW or SE winds run parallel with the coast, so the amplifying effect will be little or none at the mouth; the effect on wave turbulence will be much less but will still be positive. Ian doesn’t understand the important modifying effects of wind – those writing at “Lakes Need Water” seem to understand full well.
http://www.lakesneedwater.org/letters/lower-lakes-and-coorong-tidal-flows
For the moment I’m not going to respond to any of Ian’s vain thrashing and bluster. This is the first time ever I’ve not had to justify anything I’ve said about someone’s posts, or what I’ve said about his/her comments. All I have to do here is to show that what he claims I said, or what he claims I meant, is incorrect by re-quoting my writing and demonstrating his distortion of it; I don’t have to defend or justify anything else at all. It’s actually very easy and enjoyable, as readers may have deduced. He appears to be running out of specific insults it seems; perhaps I could lend him my unopened and unwanted copies of the “Bullshitters and Blusterers Big Book of Bile” and “101 Irrelevancies to Confound Critics” and lend wings to his waffle.
Peter R. Smith – OAM - Mannum says
Hi Debbie,
I am sorry if I accused you as I did not mean to and if I have not answered any of your questions to the best of my knowledge please ask them again.
Hi Tony Price,
No I was not referring to, “evaporation estimates” I was of the opinion from your posts that you were in favour of the removal of the Barrages but if I am wrong I apologise and as far as my, “being unreasonable and churlish, or perhaps you just misunderstood what he said and what I meant, in which case I apologise” I am trying to be reasonable about all ideas being put forward as a solution in regard the Lower River Murray but do not accept any scenarios that call for the Barrages to be removed..
Debbie says
Ian Mott,
Out of respect for the reasons why you have put your hand up in this debate (which are quite similar to mine) and also out of respect for the great deal of work you have put in that returns no personal benefit to you (to the best of my knowledge), I am going to politely ask you to explain this statement:
Snow melt used to take 30 – 40 days to flow the length of the Murray but these days it gets to spend the summer in the Hume Dam where it warms up before being released.
Because Ian, from all the research I have done, this is fundamentally incorrect on more than one level.
The evidence in fact points to the opposite.
I will also point out that this statement is therefore in direct contradiction to what you are arguing occurs at the bottom of the system re the behaviour of water when it contains turbidity levels and it is stored. In the Hume Dam (and other large storage facilities) water does behave in ways related to its temperature, its turbidity levels and therefore its comparative density.
You also need to keep in mind two other factors:
1) How much the Hume dam as a single entity actually affects what happens at the bottom of the system and…
2) How water is stored in the Hume Dam and even more importantly, how/when it is released into the Murray River at Albury.
I believe you will find that the difference in the water temperature when it finally arrives at the bottom of the system and we factor in all the other places that water comes from by the time it reaches the LRM…. is non existent…..and if we could be bothered to actually work out what the difference is…..the specific released water from the Hume Dam would actually be colder than it would have normally been by the time it reaches the bottom of the system….but I don’t believe it’s worth the effort Ian because it’s probably likely to be about a poompteenth of nothing.
Please also qualify this statement:
And while you may not understand how river water can balance sediment flows and offset the effect of the asymetrical tides, resonable men and women without a retention deficit will have no such problem.
You are correct that river water CAN balance sediment flows and probably, if it was all left up to nature, the last couple of seasons would have seen that occuring.
However….this statement seems to be resting on a false assumption that the Murray River WOULD HAVE always balanced sediment flows….and Ian….to my knowledge, no such balance has ever existed.
I do not pretend to know as much as you, Jen and Tony know about tides in the Southern Ocean but I do know that our inland ephemeral river system in the MDB does not respect ‘long term averages’ and therefore does not maintain a consistent balance with the overwhelming presence and influence of the Southern Ocean.
If it did, there would have been no need to build any of our regulatory systems in the first place!
All inland MDB communities and the communities at the LRM could have just relied on the regular and balanced flows and formed their ‘sharing’ rules around that.
I hope you don’t decide to take offence at this comment because I do sincerely respect your reasons for being involved in this debate.
However, I do not believe your assertions about the behaviour of the inland rivers in the MDB are likely to stand up to scrutiny.
Tony Price says
Comment from: Ian Mott May 2nd, 2012 at 11:58 am
Ian Lecturing Debbie on Tidal Prisms:
“The tidal prism is the volume inside an estuary mouth that is subject to tidal variation. So a 1000 hectare area that experiences a 1 metre tidal range (ie 10ML/ha) will have a tidal prism with a volume of 10,000ML. And this 10,000ML then forms the upper limit of inflow volumes that a 1 metre tide can deliver.
If the area was 2000ha then the upper limit of inflow volume with the same tidal range would be 20,000ML and it would mean that, assuming the same mouth cross section, the flow would be twice as fast and it would bring in four times more sediment than it would for the 1000ha prism area.”
This is in the “making it up” and “nonsense” categories.. Twice as fast”? There are three factors which influence influx of water; height of the tide, cross-sectional area of the mouth, height of the water behind the mouth. The only force driving the influx is water pressure, defined by height of tide and constrained by the cross-section of the mouth. If the level of water behind the mouth sandbar is lower than that sandbar, the influx will be at a constant rate, which is also the initial rate, and also the maximum possible rate. Initially a low-height tidal wave spreads out across the prism area. Once that wave has covered the prism, the height of water there begins to increase. Once that level equals the height of the mouth sandbar, any further increase reduces the difference between the inner/outer levels. It’s that difference which defines the pressure differential, so as the height difference reduces, the pressure difference drops, and the rate of influx drops, finally to zero when the water level inside is equal to the level outside.
Put simply, it’s the height differential between the water outside and that inside which controls the rate of inflow. Initially, the size of the prism has no effect; the influx of water hasn’t even crossed it, let alone begun to fill it. When the influx has crossed it, it begins to fill, and the result is a reduction in inflow. There can be no doubling, tripling or any other -ing of the rate according to the size of the prism. The only effect the size of the prism has is on how soon the influx slows. If the inner prism is doubled, it will take twice as long to fill, all other things being equal, not fill at twice the rate; it obviously cannot.
To see how ridiculous this assertion is, consider the exact opposite: The water inside and outside is at the same level, and the tide begins to ebb. Water now starts to flow out of the mouth, the rate increasing as the level outside drops. If the outflow is proportional to the area of the outer prism, which is now the entire Southern Ocean, and thousands of times larger than the inner prism, is the outflow rate thousands of times bigger than the previous inflow rate? If water flows along a channel (river, gutter, what you will) is the flow greater if the channel is longer?
Before lecturing someone, make sure first that you know what you’re talking about, second that you can exercise simple logic, and last but not least, that there’s not someone around who either knows more than you do, or can identify total and utter bovine excreta when they see it.
Tony Price says
Comment from: Peter R. Smith – OAM – Mannum May 5th, 2012 at 9:42 am
“Hi Tony Price,
No I was not referring to, “evaporation estimates” I was of the opinion from your posts that you were in favour of the removal of the Barrages but if I am wrong I apologise and as far as my, “being unreasonable and churlish, or perhaps you just misunderstood what he said and what I meant, in which case I apologise” I am trying to be reasonable about all ideas being put forward as a solution in regard the Lower River Murray but do not accept any scenarios that call for the Barrages to be removed.”
Your apology accepted as gracefully as it was made, but it wasn’t really necessary – I’m less sensitive than some here. I’m also “trying to be reasonable about all ideas being put forward as a solution in regard the Lower River Murray” which is why I haven’t expressed an opinion one way or the other. On the face of it, I think the barrages create more problems that they were intended to solve, but I also think “act in haste, repent at leisure”. Removal might solve some problems but almost certainly create others. I’m not taking sides in this debate, merely trying to “stir the pot” and point out errors in arguments and proposals (as I see them, I speak for no-one else), and make people think. That has the added benefit of making ME think, and that’s good.
Years ago, part of my job involved risk assessment, and I learned a lot of fundamental principles back then. One was that every aspect must be examined and assigned a relevance or importance rating. You shouldn’t give equal weight to problems of differing impact or cost. (Some of) the real questions, to my mind at least are:
1) What are the barrages achieving right now?
2) Are those achievements/benefits in any way significant, and if so how significant?
3) What are the cost and ecological and other impacts of losing those benefits?
4) What are the cost and impacts of removing the barrages? – note that it may not be a black & white situation, perhaps only some of the barrages should be removed, and some remain, possibly to perform some function or achieve some benefit that they weren’t originally designed for. Just a thought, might be irrelevant, but shouldn’t be dismissed out of hand.
5) If some or all of the barrages are removed, what must be done (if anything) about the river(s)? Are there any impacts or cost implications wrt the rivers? I know there is at leas one suggestion of a dam or more likely a lock of some kind, with access for fish going up river to spawn.
6) Apart from the cost of physical removal, are there any consequent costs or negative ecological impacts, and what is the relative size and/or importance of each?
7) If barrage removal is intended to return the lakes to a salt-water or at least salty environment, how successful is this likely to be? Clearly any purely fresh-water species will lose out to the point of extinction.
8) The success of any subsequent outcome after removal will depend, to a greater or lesser extent on the mouth remaining open, at least for part of the year, to keep the lakes in good health.
9) Will removal achieve this healthy outcome?
10) Will removal achieve an open, or partly open mouth by itself, or will it need assistance in some way, e.g. dredging, or inner channel modification, or perhaps even complete removal of an obstruction to flow, e.g. Bird Island? If so, what assistance, and at what cost, financially and ecologically?
11) Is anyone still following me?
12) Can all or most interested parties come together to at least identify major issues, and establish some facts amid the politics, vested interests and pet theories?
If this looks suspiciously like a brain-storming exercise, you’re right, that’s exactly what it is. Seemingly off-beat ideas, or apparently insignificant points or observations shouldn’t be dismissed out of hand. Think, discuss, weight, accept or reject or modify. It’s an informal version of a decision-making model my then employer paid a lotta dosh for some years ago. It proved to be worth its weight in gold, sometimes throwing up previously unthought-of solutions or pitfalls, and most often identifying the best all-round and cost-effective solution, which in many cases totally satisfied no-one. I’ve used this informal but structured approach ever since to good effect.
Seems to me minor issues are often blown up out of proportion, and seen as major ones by some. Could these be identified, and put on one side or thrown out of the discussion? There’s far to much partisan feeling involved, and that’s not healthy. The only likely result is perpetuation of the status quo, which is likely in the end to satisfy no-one, whatever some may think.
These questions and their many possible answers are complex, and I doubt any one person or even organisation is qualified or equipped to provide those answers. A large part of the problem is even defining what the questions ARE, let alone answering them. I’m certainly not qualified, though at least I’m learning what the questions might be. It’s a necessary first step towards answering them!
Debbie says
Excellent questions Tony,
They are certainly making me think and I agree that a large part of the problem is that we are not asking the right questions and also that we are therefore not clear about what it is we want to actually solve or for that matter what we’re trying to achieve.
I do have a further question related to this comment however:
‘Clearly any purely fresh-water species will lose out to the point of extinction.’
Are there any purely fresh-water species in those lakes that are unique to that area only and therefore in danger of becoming extinct?
I would imagine that unique fresh water plant species would likely be the ones that we would need to be concerned about.
Fish, birds, frogs etc are generally capable of moving upstream…provided the regulatory structures allow access for the fish.
I don’t know the answer to the question BTW, but maybe someone else does?
Debbie says
Peter,
I’m not sure why I’m bothering…. but you have asked…..
Comments such as this one do nothing at all to advance any discussion you are having with me:
Hi Debbie,
Good to see you are back supporting fiction!
When I agreed with Ian Mott that the conundrum over the barrages and keeping those Lakes always fresh is ultimately SA’s choice with a qualifier that there is nothing on the table (so far) that shows SA is prepared to solve the problem there…you replied:
‘as for what SA wants it must be remembered that the cost of maintaining Murray Darling Infrastructure is shared, NSW 38%, Vic 35% and SA 27% so decisions must be made by those three States and the MDBA.’
When I asked a further hypothetical question about that statement you answered with a totally unrelated question/comment and then also inferred that I had accused you of using false figures….you also inferred the same with the point I was trying to make about the 20% figure.
When I asked your opinion of Josephine Kelly’s article with a little of my thoughts to help you get started here:
Did you read the article by Josephine Kelly that John posted?
Doesn’t her main point lie at the bottom of this mess?
The people who have the most to lose and the least resources are the ones who have had ‘the burden of proof’ dumped in their court.
It makes it very easy to ‘divide and conquer’.
You just answered that you read it….which I guess you can say answered a question….but that obviously wasn’t the question I was asking you to answer….
Hope that now answers your question?
Peter R. Smith – OAM - Mannum says
Hi Debbie,
Re “snow melt water” we down my end of the River always knew when we were getting the snow water because the water was colder but I cannot remember when I noticed that last.
Re the tides I have been trying (unsuccessfully) to explain the situation is different in the Southern Ocean near the mouth of the River Murray.
Your point about averages is correct but no one seems to be listening they still quote then as the norm.
Also once again correct, “All inland MDB communities and the communities at the LRM could have just relied on the regular and balanced flows and formed their ‘sharing’ rules around that” I am glad we didn’t the regulation was a must!
Hi Tony Price,
The reason we believe the Barrages must stay as by removing them that will create massive problems in the Lower River Murray.
Yes, “On the face of it, I think the barrages create more problems that they were intended to solve, but I also think “act in haste, repent at leisure” is what people could think of they did not understand the area.
Yes stir the pot by all means it is the best way to have all options properly investigated.
Looking at your questions I shall answer them from our point of view: –
1) What are the barrages achieving right now?
Answer – Whilst there is sufficient inflows into the MDBasin and over Lock 1and out through the Murray mouth the Barrages are achieving half of the reason they were constructed allowing sediment/salinity to be emptied out
into the Southern Ocean.
2) Are those achievements/benefits in any way significant, and if so how significant?
Answer – That significance is flushing.
3) What are the cost and ecological and other impacts of losing those benefits?
Answer – Without the flushing the Lakes Alexandrina and Albert would become (over time) a muddy sediment/salinity filled mess virtually good for nothing.
4) What are the cost and impacts of removing the barrages? – note that it may not be a black & white situation, perhaps only some of the barrages should be removed, and some remain, possibly to perform some function or achieve some benefit that they weren’t originally designed for. Just a thought, might be irrelevant, but shouldn’t be dismissed out of hand.
Answer – If any of the Barrages were removed the affect would be that when (like during the drought) there were no flows over Lock 1 salt water i.e. the sea would enter un-inhibited and the Lower River Murray would become saline firstly Lake Albert would become hyper-saline followed by Lake Alexandrina and the River Murray to
Lock 1 would, whilst not become hyper saline all pump outs for irrigation, human consumption etc would be un-useable. All Flora and Fauna relying on freshwater would eventually perish. We believe the Lower River Murray would never recover as it would/could become impossible to flush out all of the salinity.
5) If some or all of the barrages are removed, what must be done (if anything) about the river(s)? Are there any impacts or cost implications wrt the rivers? I know there is at least one suggestion of a dam or more likely a lock of some kind, with access for fish going up river to spawn.
Answer – If some Barrages where removed the decline would begin as soon as there were no flows over Lock 1.
I don’t believe there is anywhere in SA to build a dam of any significance. I am the spokesperson for the Lock Zero group (It can be viewed on my web site http://www.psmithesrmyriver.com)
6) Apart from the cost of physical removal, are there any consequent costs or negative ecological impacts, and what is the relative size and/or importance of each?
Answer – As far as the cost of removal I have no idea though we have been seeking a total up-grade of the Barrages for some years and believe the cost of Lock Zero could be as much as $1-Billion.
7) If barrage removal is intended to return the lakes to a salt-water or at least salty environment, how successful is this likely to be? Clearly any purely fresh-water species will lose out to the point of extinction.
The success of any subsequent outcome after removal will depend, to a greater or lesser extent on the mouth remaining open, at least for part of the year, to keep the lakes in good health.
Answer – Firstly all freshwater species and vegetation would perish and we believe the mouth would/could completely close during times of low flow and as I said before, “If any of the Barrages were removed the affect would be that when (like during the drought) there were no flows over Lock 1 salt water i.e. the sea would enter un-inhibited and the Lower River Murray would become saline firstly Lake Albert would become hyper-saline followed by Lake Alexandrina and the River Murray to
Lock 1 would, whilst not become hyper saline all pump outs for irrigation, human consumption etc would be un-useable. All Flora and Fauna relying on freshwater would eventually perish. We believe the Lower River Murray would never recover as it would/could become impossible to flush out all of the salinity.”
9) Will removal achieve this healthy outcome?
Answer – No1!
10) Will removal achieve an open or partly open mouth by itself, or will it need assistance in some way, e.g. dredging, or inner channel modification, or perhaps even complete removal of an obstruction to flow, e.g. Bird Island? If so, what assistance, and at what cost, financially and ecologically?
Answer – We believe removal will ensure the only way to keep the mouth open will be by dredging.
11) Is anyone still following me?
Answer – Yes!
12) Can all or most interested parties come together to at least identify major issues, and establish some facts amid the politics, vested interests and pet theories?
Answer – Re, “If this looks suspiciously like a brain-storming exercise, you’re right, that’s exactly what it is” we have been doing this for nearly a decade but can’t get the powers to be to listen.
Hi Debbie,
I hope my answers are understandable if not just ask differently.
Re, “Are there any purely fresh-water species in those lakes that are unique to that area only and therefore in danger of becoming extinct” there are some freshwater species found only in the Lakes but many others that would perish and that includes fish, crustations and turtles.
Re, “Fish, birds, frogs etc are generally capable of moving upstream…provided the regulatory structures allow access for the fish” that is correct but the ‘regulatory structures’ would be the problem.
Re, “Josephine Kelly’s article” it did not turn on any lights for me!
As I have already pointed out my mistake with the shared costs of infrastructure management.
If you believe that I accused you re the 20% figure my apologies though I feel that is an important point.
Tony Price says
Thanks for your detailed point-by-point response, Peter. It’ll take me a little while to go through that before I respond. Thanks also for restoring a little calm and decorum to this thread, and by your responses assuring me that I’m beginning to get a handle on this complex topic, even if I have no answers (does anyone, in truth?).
Debbie says
Peter,
On your advice, I will attempt to ask my questions differently:
When (as in specific timeframes) did you know it was definitely snow water?
How did you know it was specifically snow water?
How is your snow water comment actually relevant to my post and the point of my post?
In what specific way is the Southern Ocean different at the Murray Mouth? Compared to what specifically?
What are the specific fresh water species that are unique to the lakes?
Why didn’t the article turn on any lights for you?
Peter R. Smith – OAM - Mannum says
Hi Debbie,
Re, “Snow water” I have not really noticed the colder water for probably 10 or so years.
Re, “How is your snow water comment actually relevant to my post and the point of my post?” it probably wasn’t specific re your point but I was explaining about the realisation we were not getting snow water any longer.
Re, “In what specific way is the Southern Ocean different at the Murray Mouth? Compared to what specifically?” the Southern Ocean is where the Murray River empties to the sea, yes we all know that, but the tidal influences is not the same as on the Eastern seaboard.
Re, “What are the specific fresh water species that are unique to the lakes?” there are some really same fish (I don’t know the names of them that are unique to the Lakes area and of course freshwater Brim, Golden Perch, Murray Cod etc.
Re the, “Josephine Kelly” article and the Basin and Climate Change all we can do is ensure we continue to monitor change, use the best scientific information into attempting to work out the best way to move forward, but isn’t this what we do all the time?
It would be great if we didn’t have to rely on politicians to make the decisions about our future!
Debbie says
Peter,
Doing my best to frame my questions in the right manner.
If we are talking about 10 years ago, what has changed that stopped you from getting what you claim was snow water?
How did you know it was specifically snow water about 10 years ago?
When did anyone say that the Southern Ocean was the same as the Pacific Ocean?
Also, in what specific ways is the difference between the Southern Ocean and the Eastern Seaboard relevant to this discussion?
You are claiming that there are fresh water species unique to the lakes, why can’t you name them?
The species you have named are not unique to the lakes are they?
Where can we locate the best scientific information that would actually be able to help us to work out the best way to move forward?
Why has the science focused on numbers rather than looking for ‘best ways’?
Why does that number keep changing?
Why do we have to rely on politicians to make these type of decisions about our future?
Peter R. Smith – OAM - Mannum says
Hi Debbie,
Re, “If we are talking about 10 years ago” I don’t really know we stopped noticing the colder cleaner water not getting to below Lock 1 like it used to, maybe it was more than ten years ago. It is often a topic of discussion with some of the old timers’.
Re, “How did you know it was specifically snow water about 10 years ago?” another I am not sure but Darling water is always a different colour.
Re, “Also, in what specific ways is the difference between the Southern Ocean and the Eastern Seaboard relevant to this discussion?” the tidal movement.
Re, “You are claiming that there are fresh water species unique to the lakes, why can’t you name them?” I have email a friend and are waiting for that answer.
Re, “The species you have named are not unique to the lakes are they?” no there aren’t but will perish if the Barrages are either opened or removed to allow seawater to enter Lake Alexandrina.
Re, “Why do we have to rely on politicians to make these type of decisions about our future?” I wish the answer was no!
Debbie says
Peter,
Who is claiming that the tidal movements are the same?
Which old timers and how did they know it was specifically ‘snow water’?
The question about those named species has not been answered, you have answered another question I didn’t ask.
Who said they wouldn’t perish if sea water was allowed in and they did not move upstream?
Wasn’t the question about species extinction?
I will be interested to know if there are indeed fresh water species unique to the lakes. It appears you are like me and you do not know the answer to that question?
You also didn’t answer my last question, it was not a closed question, so yes or no does not answer it.
May I suggest you go to Jen’s latest post and ask yourself whether the MDB conundrum is perhaps being rather heavily influenced by what is being discussed there?
Tony Price says
Debbie said:
Where can we locate the best scientific information that would actually be able to help us to work out the best way to move forward?
Why has the science focused on numbers rather than looking for ‘best ways’?
Why does that number keep changing?
There seems to me to be a major disconnect in some of the thinking on this topic. If you read my list of questions above, you should have noticed a strong element of “if this is done to achieve that, will it achieve that and also will it change the situation in other ways not yet thought of?”. I said before “act in haste, repent at leisure”. I’m a great believer in the “Law of Unintended Consequences”, and there are many examples of it in operation.
It is entirely possible that the removal of the barrages might have such consequences, though I’m beginning to believe (a feeling, no more) that most could be identified and adapted to, or mitigated against. My gut feeling is that removal would be the best option in the long term, but I’m hard-headed and logical enough to realise that it’s not sensible to base conclusions and decisions on gut feeling. Ian’s pipes are, on the face of it, a good idea, but it’s a half-baked one (I mean than in the best possible sense); all the practical problems of building them, the operation of the “non-return valves” and the great difficulty of actually stopping sand entering the seaward ends and finally clogging them up haven’t been discussed, let alone solutions found. There may well be a height of channel/seabed difference which would preclude their use. They wouldn’t be of much use if the inner ends ended up under metres of sand.
I haven’t seen mentioned anywhere the idea of cutting a new mouth; everything focusses on the existing one – dredging it and inside the mouth (seems to me rather like peeing into the wind), pipes to augment the flow either side, etc. The existing islands are largely made of sand and sediment, the sandbanks and bars obviously are, and their pattern was formed before the barrages were built, with the mouth roughly where it is now, and modified since. The ancient mouth defined the islands and sand bars, those islands and sand bars modified the mouth, and the barrages changed everything. It could be argued that once the barrages were built, that the mouth was then (and now) in the wrong place. A look at the map shows that a more logical place would be opposite the Tauwitchere Barrage – it looks like the obvious place, directly opposite the widest channel to Lake Alexandrina.
Creating it would be an enormous challenge – excavating something like 4sq. km of dunes. Critics might scoff, but how much sand have the dredgers shifted (not disposed of, just moved about a bit) so far, and how much will they have to shift in the future? Maybe SA could become a major exporter of sand to the rest of Oz and the world. Just think – the list of exports could be headed “Coal, sand, Foster’s lager” with Flannery’s flummeries”at the bottom and with desalinated water not getting a mention. I might jest, but there’s a serious message herein.
To a greater or lesser degree, the difficulty of identifying both short-term and long-term effects and consequences is common to all solutions, partial or otherwise, and equally important for those who support the status quo, which also might have unintended consequences. I know I’m not helping much but I have to get my head around this; I’m hooked, and talking (writing) out loud helps. Writing things down for others to read focusses your mind on detail and clarity of expression. It’s good to talk but it’s even better to write. It might even help others here (who knows?).
Peter R. Smith – OAM - Mannum says
Hi Debbie,
Re, “Who is claiming that the tidal movements are the same?” I have been stating there is a major difference in the way the estuaries on the East coast are formed for many years and Jen and yourself have continued to ask why and in what way now you are contradicting yourself by asking, “Who is claiming that the tidal movements are the same” fair go Debbie.
I am sorry as I often forget how much you know about the LRM re, “Which old timers and how did they know it was specifically ‘snow water’?” as I listen to the what those who have lived on the LRM for in some cases over 80 years.
In my last post in answer to your question I wrote, “Re, “You are claiming that there are fresh water species unique to the lakes, why can’t you name them?” I have email a friend and are waiting for that answer” read before making comments.
Re, “Who said they wouldn’t perish if sea water was allowed in and they did not move upstream?” I do not want to see maybe hundreds of thousands of freshwater fish perish as swimming upstream if the River to Lock 1 becomes saline.
Re, “I will be interested to know if there are indeed fresh water species unique to the lakes. It appears you are like me and you do not know the answer to that question?” as above I am seeking clarification.
Re, “You also didn’t answer my last question, it was not a closed question, so yes or no does not answer it” which was “Why do we have to rely on politicians to make these type of decisions about our future?” how do we get out of accepting what our politicians have passed through parliament.
Don’t kid yourself re, “ask yourself whether the MDB conundrum is perhaps being rather heavily influenced by what is being discussed there?” if you think what we are posting would make any difference, it would be good to think it would but I fear alas.
And re which is, “Jen’s latest post?”
Peter R. Smith – OAM - Mannum says
Hi Tony Price,
Re, your answer to Debbie, “Where can we locate the best scientific information that would actually be able to help us to work out the best way to move forward?” that is the $64,000 question as all authors of information believe theirs is the best.
Re, “act in haste, repent at leisure” that is 100% correct the ramifications of removal (as I have continually stated) are a disaster without constructing Lock Zero.
I believe that the mouth has moved many times of the last seven thousand years but actually moving it be engineering I really don’t know but I do know the Ngarrindjeri would be violently opposed to, “excavating something like 4sq. km of dunes.”
Re, “To a greater or lesser degree, the difficulty of identifying both short-term and long-term effects and consequences is common to all solutions, partial or otherwise, and equally important for those who support the status quo, which also might have unintended consequences” I don’t believe is difficult as in the short term, whilst there are large enough flows over Lock 1, the mouth will remain open therefore continuing to clear all sediment being transported down the River from the source. But if or when there is no flow over Lock 1, and it will happen again, Lake Alexandrina will be disconnected from the Southern Ocean and both Lake Albert and Lake Alexandrina will become hyper-saline and the Lower River Murray will become saline.
Debbie says
Thanks Tony,
There is indeed a serious disconnect. We all do need to ask more questions and we all need to try and recognise what we want to achieve. You have certainly made me think and your questions have helped me to focus on goals and not keep falling back into this urgent ‘political’ trap.
Peter,
I am trying to make my questions as simple and direct as possible but you’re still not answering them, you are still firing personal shots at me and you are still making/asking irrelevant comments/questions.
If you don’t know the answers or you don’t want to answer then that’s your call. Please cease pretending that it has something to do with me (in terms of my knowledge, my motivations, my opinions about the barrages etc)
Tony Price says
Comment from: Debbie May 7th, 2012 at 10:33 am
Thanks Tony,
There is indeed a serious disconnect. We all do need to ask more questions and we all need to try and recognise what we want to achieve. You have certainly made me think and your questions have helped me to focus on goals and not keep falling back into this urgent ‘political’ trap.
Thanks for that – it at least assures me I’m not wasting my time and yours. Those responsible for the “Lakes Need Water” website have done a lot of work, covered a lot of ground (water?), and provided a lot of historical fact and many statistics. But, and it’s a big but, the site lacks “top down” structure IMHO, and the message, though strong, gets somewhat lost in detail, and thus diluted (an appropriate metaphor, in the circumstances). Links take the reader off in all directions, it’s tricky to get back to where you were, and that’s not good. There should be two main sections – the report and the proposal(s). If the time comes for a submission, most of the work will have been done, and most of the appendices will be almost in the form needed. The rest is for the interested reader, as background or reference.
Whether the best long-term solution is to open the barrages with a view to removing them altogether, or do that but keep them as a flood-prevention measure, or to remove them entirely, the current policy of buying back valuable fresh water in order to throw it in the general direction of the mouth just to shift some sand seems loopy to me.
I think it was Ian who said that one half-decent storm could undo the work of months of increased flow. The powers-that-be, in their haste to please everyone, have succeeded in disappointing everyone equally, and spent a lot of money, not their money of course, in doing it. Unintended consequences again. I may be wrong here, but it’s the impression I get.
Peter R. Smith – OAM - Mannum says
Hi Debbie,
As I have said plenty of time I will always do my best to answer all your questions I never shy away from inquiries.
To that end I have spoken to a number of commercial fishermen who operate in Lake Alexandrina re fish etc.
Over the last twenty plus years a number of species have already disappeared and if Lake Alexandrina became saline (sea water) firstly the level would drop by a minimum of 0.75-Metre and tube worms would become a problem for turtles, 2 species of freshwater snails, yabbies and freshwater mussels therefore wiping them out downstream of Lock 1.
The endangered fish that would be wiped out are Yarra Pigmy Perch, Purple Spotted Gudgeon, 2 species of Hardy Head, Black Fish and of course other fish upstream to Lock 1Silver and Golden Perch, Catfish, Murray Cod, Redfin and Bony Brim and of course European Carp but that would be good.
If you believe I am, “firing personal shots” maybe you need to get thicker skin because I am not concerned at what people say as long as check to make sure what I say is correct.
Debbie says
Peter,
My question was definitely about species that are unique to the lakes ….I may be incorrect but I do not believe the ones you have named are unique to that area?
They would therefore not become extinct ….not arguing that the tube worms are a problem….but didn’t that happen anyway during the drought?…with the barrages closed?
Hasn’t that problem been largely rectified because the drought broke…and therefore nothing to do with river management or upstream diversions?
I also agree ‘good riddance’ to the Carp.
My skin is fine thankyou .
Tony Price says
Keep it civil, Peter & Debbie – there’s been enough ill-feeling on this thread earlier. You’re both educating one another, that’s clear, and you’re both educating me, and vice versa, I hope. From your comments we’re at least making one another THINK, even if we’re not providing any solutions as yet, and that’s good. It’s good to talk.
Peter R. Smith – OAM - Mannum says
Hi Debbie,
Whilst some of the species ‘may not’ be ‘unique to the lakes’ is that any reason to make them extinct in the Lakes?
Yes the ‘tube worms’ caused massive problems during the drought when EC Levels rose markedly but we hope it never happens again.
I have agreed the breaking of the drought has done a massive amount of good throughout the Basin but we must come up with solutions for the future no matter what ‘Mother Nature’ throws at us.
Debbie says
Peter,
My question was a simple question:
Are there any purely fresh-water species in those lakes that are unique to that area only and therefore in danger of becoming extinct?
I did not know the answer and it was a genuine question.
You don’t appear to know the answer either and you certainly haven’t answered that rather specific question.
My answer to your question above, in relation to my original question, is they are not in danger of becoming extinct.
If it is not in relation to my question then we need to go back to Tony’s questions that prompted me to ask the question in the first place.
In particular questions 5, 6 & 7:
5) If some or all of the barrages are removed, what must be done (if anything) about the river(s)? Are there any impacts or cost implications wrt the rivers? I know there is at leas one suggestion of a dam or more likely a lock of some kind, with access for fish going up river to spawn.
6) Apart from the cost of physical removal, are there any consequent costs or negative ecological impacts, and what is the relative size and/or importance of each?
7) If barrage removal is intended to return the lakes to a salt-water or at least salty environment, how successful is this likely to be? Clearly any purely fresh-water species will lose out to the point of extinction
I would suggest that all of these things need to be considered, as a minimum, to answer your question.
Peter R. Smith – OAM - Mannum says
Hi Debbie,
Re, “Are there any purely fresh-water species in those lakes that are unique to that area only and therefore in danger of becoming extinct?” I thought you would have understood my answer, “Whilst some of the species ‘may not’ be ‘unique to the lakes’ is that any reason to make them extinct in the Lakes?”
Re, “I did not know the answer and it was a genuine question” and my answer was a genuine answer.
So in regard to, “You don’t appear to know the answer either and you certainly haven’t answered that rather specific question” you may not like the answer but that is it, “Whilst some of the species ‘may not’ be ‘unique to the lakes’ is that any reason to make them extinct in the Lakes?”
Re questions 5, 6 & 7 I thought the answers provided were quite easy to understand.
5) If some or all of the barrages are removed, what must be done (if anything) about the river(s)? Are there any impacts or cost implications wrt the rivers? I know there is at least one suggestion of a dam or more likely a lock of some kind, with access for fish going up river to spawn.
Answer – If some Barrages where removed the decline would begin as soon as there were no flows over Lock 1.
Also if one or more all of the Barrages were removed the degradation would begin immediately.
And re a dam I don’t know of any where in SA a dam of significance could be constructed.
6) Apart from the cost of physical removal, are there any consequent costs or negative ecological impacts, and what is the relative size and/or importance of each?
Answer – As far as the cost of removal I have no idea though we have been seeking a total up-grade of the Barrages for some years and believe the cost of Lock Zero could be as much as $1-Billion.
And on numerous occasions I have FULLY explained the ramifications.
7) If barrage removal is intended to return the lakes to a salt-water or at least salty environment, how successful is this likely to be? Clearly any purely fresh-water species will lose out to the point of extinction.
The success of any subsequent outcome after removal will depend, to a greater or lesser extent on the mouth remaining open, at least for part of the year, to keep the lakes in good health.
Answer – Firstly all freshwater species and vegetation would perish and we believe the mouth would/could completely close during times of low flow and as I said before, “If any of the Barrages were removed the affect would be that when (like during the drought) there were no flows over Lock 1 salt water i.e. the sea would enter un-inhibited and the Lower River Murray would become saline firstly Lake Albert would become hyper-saline followed by Lake Alexandrina and the River Murray to
Lock 1 would, whilst not become hyper saline all pump outs for irrigation, human consumption etc would be un-useable. All Flora and Fauna relying on freshwater would eventually perish. We believe the Lower River Murray would never recover as it would/could become impossible to flush out all of the salinity.”
Debbie says
Peter,
I do not want to be offensive but you are truly confusing me here.
This is not an answer to my question:
“Whilst some of the species ‘may not’ be ‘unique to the lakes’ is that any reason to make them extinct in the Lakes?”
That is most definitely a question…. which I attempted to answer in relation to my first question.
Actually to be pedantic…yours is a rhetorical question that contains your own answer inside your own question….which wasn’t my question.
See why I’m confused?
If you don’t know the answer to my original question…that’s perfectly OK….I don’t know it either….that’s why I asked it.
The remainder of your post was your answers to Tony’s questions….I’m reserving my judgement on those until he finds the time to deal with those….although there is no question he has got me thinking.
My question was simply a clarification question….and I’m not ‘clarified’ at this point.
Ian Mott says
So, after another 4 days Jennifer has still stated whether she accepts or rejects the link between flow velocity and sediment load.
And after 4 days Price has not bothered to explain how river water might reduce tidal inflows.
And Debbie just lost the plot altogether.
What little Price has revealed under all that self indulgent verbage is how little he actually understands about tides when he claims the size (volume) of the tidal prism has nothing to do with the velocity of inflow.
He forgets that an in flowing tide starts at low tide and continues to high tide. He correctly points out that the size of the cross section (including sand deposits inside the mouth) are one determinant of inflows. But if he didn’t have his head so far up his own backside he would understand a bit about what we call “head” or the drop from where the water starts and where it finishes up. He would understand that the available channel cross section increases as the tide gets higher. And this means that less water must flow to fill a small tidal prism than must flow to fill a larger prism.
The channel cross section is smallest at low tide so the capacity for the channel to fill the bottom of the prism is restricted. And when the prism is larger then that capacity to fill is further restricted. And as the tide level outside rises this results in a greater difference in water levels between inside and out. Ergo, the speed of inflows increases as the tide rises.
The larger the tidal prism, the more water is required during the inflow phase to keep water levels close to matching. But if the channel restricts this flow then a greater height difference is produced and the speed of inflow increases in line with the increased head or slope of flow. The same obviously applies to the outflow but, in cases like this where the tides are asymetrical, the outflow is slower because the lowering of tide height is lower.
A smaller tidal prism requires less flow to match the levels outside the prism so the slope of the flow is less, the speed of flow is lower and the volume of sediment carried is also lower.
But instead of actually getting himself up to speed on yet another basic principle of fluid dynamics, price goes trolling through my posts looking for anything that a twisted nutter could misconstrue. A good example is his response to statement about tides going back out six hours later. This was clearly a general reference to the fact that tides change. Water that was flowing in three hours before high tide will be flowing back out three hours later. Only a seriously biased bogan would interpret this as meaning the entire tidal cycle was completed within six hours.
Debbie, it is generally accepted that it normally takes 25 days for water to flow from the Hume Dam to the SA border. So 30 to 40 days to flow from the snow fields to the mouth (if unimpeded by dams) is an entirely reasonable conclusion. Nowhere did I ever suggest that the entire annual snow melt has gone out to sea in such a short time because the entire melt period lasts longer than that as the lower level snow melts first. And unless you can show me that there is zero thermal circulation in large dams I will continue to assume that these days melt water mixes with existing dam water which has already had significant exposure to sun, and warmer water is released into the river below. And it is obvious that the volumes being released are far more measured than the pre-dam snow melts so a greater proportion of the flow volume will be warmer. You may not think it is significant but logic suggests otherwise.
So where does that leave us?
With a blog full of goons who go out of their way to find anything in a post they can misinterpret to absurd lengths to support their fragile preconceptions.
With a groupthink that appears to reject the basic hydrological reality that flow volume determines sediment load.
A groupthink that still refuses to accept the implications of asymetrical tides.
A leader that refuses to respond to key elements of the science.
And a bunch of campaigning zealots who accuse others of “junk science” when they do not even understand the most basic interrelationship between the size of a tidal prism, the slope of a channnel flow and its speed.
So I will leave you folks to your little onanistic indulgences, safe in the knowledge that engineers and hydrologists who are free of such cognitive impairments will know exactly what I am talking about. I hadn’t realised how pleasent life was without this little inbred coven until I got another dose of it. But don’t worry, it is nothing that a good long shower won’t fix.
Tony Price says
Just when we thought it was safe to go back in the water, Mr Mott appears to accuse others of not understanding what he’s written in the past, and to accuse others of not understanding fundamentals that they’ve not disputed, and to make a pathetic excuse of an explanation for his ridiculous “twice the prism equals twice the flow”, which he’s now effectively agreed was garbage. His latest burst of hot air is therefore not worthy of detailed reply, it’s just more of the same.
Debbie says
Ian,
I’m willing to concede that you did not mean this statement to read the way you did indeed write it.
It was a straight copy/paste.
Snow melt used to take 30 – 40 days to flow the length of the Murray but these days it gets to spend the summer in the Hume Dam where it warms up before being released.
I am also not questioning what any of you are saying about the tides….I don’t know as much as any of you about those tides…I have only questioned the assumptions about the ‘consistent’ power of the river…..and also your assumptions about the temperature of water relased from the Hume Weir….which I am also familiar with.
I have no wish to get in a slanging match with you but please….you need to be careful about what you’re claiming about the water temperature from the Hume Weir.
In particular, water from the Hume is not released from the top where I would agree that it would be warmed from exposure to the sun in the summer months.
I would also agree that during the drought when the storage levels in the Hume Weir got down to single digits (and that included very, very limited snow melt) the water was generally warm.
The Hume weir is actually a big structure and when it is full….as it is now….it is also deep, especially at the bottom of the wall….I have forgotten the height….but is is big….have you been there?
Water is released from the bottom and you probably don’t need me to explain the reasons why that water would be significantly colder than the water that is already in the river, especially when turbidity levels are factored in….disregarding whether snow melt is included or not….and disregarding the fact that the actual amount of water that comes from the Hume specifically that ends up at the mouth (as a %) would probably make very little difference to the temperature of the water once it arrives there.
But when that weir is full, the water that gets released into the river is way colder than the water in the river just below it….way colder…..even in the cooler Spring season.
And again….the difference that makes once it eventually arrives at the mouth….approx 20 days later….and mixed in with other sources like the ‘Bidgee, the Darling, The Lachlan etc….is probably not significant anyway….but I have never seen a study done on that….have you?
There are however studies done on the effect of cold water releases directly below the big storages.
Because that water is sometimes very, very cold.
Hope that helps to clear up any misunderstanding?
Ian Mott says
Price claims that he knows a bit about tides but the “bit” that he knows does not include any consideration of the role of different heights in flows between two water bodies. Do all the lurkers on this thread really comprehend the scale of this man’s ignorance? Do you, like Price, attribute tidal flows to something other than differential water levels between two connected water bodies? Do you actually understand how stupid this man has managed to make you all appear?
You all, especially Jennifer, had 4 days to reflect on what he said and not one of you said, “hey wait a minute, Tony”. And it tells us a great deal about the poor quality of the AEF’s “peer review” processes.
So lets walk through this really slowly, shall we? Lets assume low tide is zero height and high tide is 1 metre and the inflow period is 10 hours. That would mean an approximate 10cm rise in sea level every hour.
So who among you, other than Price, is prepared to claim that a doubling of the area inside the channel will not require an approximate doubling of water flow to ensure that both water levels rise at a similar rate?
And who among you, other than Price, is prepared to state that any shortfall in that additional water flow in that first hour will produce a greater height difference between the two levels which will then produce a steeper slope/drop/head that will produce a faster flow in subsequent hours until the difference is addressed?
Stop hiding Jennifer? A larger tidal prism caused by the removal of the barrages MUST produce faster flows in both directions. And if the tides were symetrical then that faster flow would create a wider mouth. But that is not the case in SA and it can only mean the mouth will be closed by faster inflows depositing more sand than outflows can remove.
And stop hiding behind that ignorant crap about large waves taking sand away. We are talking about the inside of an estuary here, not the damned beach. Of course large waves agitate more sand than small waves. But the form of that greater sand disturbance is for it to be transported along the beach until it finds an inflowing (or outflowing) channel. And when that sand arrives inside that calmer water body the sand settles. The narrow face of the wave passes along the channel and then spreads (fans out) when it passes into the wider dimensions of the estuary. Its power dissipates and the sand settles. Its Geography 101 and you failed miserably.
So could all of you AEF clowns kindly stop poncing about like village idiots in the middle of a serious issue. The first obligation of anyone who accuses anyone of “junk science” is to make damned sure their own science is of the highest standard. All you have managed to do is reinforce a lot of anti-farmer prejudices and make it so much easier for the forces of darkness to ignore our legitimate concerns.
“My most feared enemy is a foolish ally” Sun Tsu.
Ian Mott says
Tony, your post of May 6th, 5.32 shows that you still have not read my reference submission. It does look at the option of other channels and explains why the same asymetrical tides will close them even faster than the existing one.
It does explain how the seaward end of the pipe, if located below the wave zone but well above the sea floor, will only suck in clean, sand-free water which cannot then block the pipe.
It does explain how a smooth pipe surface delivers water more efficiently than a rough sand sided and bottomed channel.
It does explain why a pipe system based on passive inflows on the high tide will maintain the Coorong at AHD while a system based on passive outflows can only work on the lower half of the tide range and can only produce Coorong levels lower than AHD.
It does explain how a simple flap, hinged from above, on the inward end of the pipe will allow water to flow in but be pushed closed by returning water. There are numerous methods of making cheap one way valves that can operate passively without human input.
And my second submission to the MDBA points out that Ngarrindjerri objections to excavation of the dunes would not appear to apply to the area near the current channel because those dunes have already been subject to major disturbance by nature when the mouth moved many kilometres in both directions in recent history. That would make the sand in the disturbed parts of the dunes no different to beach sand that has been deposited inside the mouth which has been subject to dredging for much of the last decade.
It is obvious that both of us could have started this exchange a little better. But “the moving finger writes, and, having writ, moves on etc”. The approved way of dealing with such issues, if or when we ever meet, is to say, “get f@#&d Mott” and pass the Port.
Tony Price says
There Ian goes again – he doesn’t know what I know or don’t know, and he doesn’t know what I have read or not. I have almost finished a detailed critique (which I will post on my blog) of his submission, which is almost entirely unreferenced, despite my initial impressions. In his comments here, Ian has been citing his own work in support of his arguments. Listing a few publications at the end cuts no ice with critical and informed readers. Under peer review, this submission wouldn’t get beyond the waste bin in the Journal’s post room.
His submission had not, and has not, a cat’s chance in hell of being taken seriously by anyone with any knowledge of hydrology, or tides, or the cost of construction, or the depth of water in the Coorong. It’s a submission that most peculiarly for the subject matter, doesn’t contain the key word “scour”. It’s a proposal to install pipes to increase sea water flow beyond the Murray mouth and under the peninsula to the Coorong, yet contains, for example the astonishing statement
2.74 Precise estimates of the likely cost of installed pipes are beyond the scope of this
paper…
Reply: And you expect this submission to be taken seriously?
2.09 When sea water can be substituted for fresh water the limit to the annual cost of any
infrastructure required in its capture, transportation and delivery to the place of use is
defined by the spot price/ML of the fresh water it is replacing. The capital cost of
infrastructure for the delivery of sea water is defined by the market price/Ml of a
fresh water allocation, plus an additional premium for the substantially improved
reliability of sea water supplies.
Reply: The capital cost of infrastructure for the delivery of sea water is defined by the capital cost of infrastructure for the delivery of sea water, and nothing else. It has nothing to do with the price of fresh water.
2.10 The difference between the market price of fresh water and the delivered cost of sea
water is the marginal profit from the substitution process. The gross profit from the
substitution is the marginal profit x the volume of all fresh water supplied.
Reply: The difference between two costs is not profit, marginal or otherwise.
2.01 A purely hydrological function like the transportation of sand and sediments can be,
and currently is, performed with equal effectiveness by equal volumes and velocities
of sea water or fresh water.
Reply: This statement is in a submission which makes much of the imbalance between inflow and outflow volumes and velocities. It can also be performed with equal effectiveness by differing volumes and velocities of sea water or fresh water.
2.52 A detailed analysis of the two kinds of tidal patterns shown in the graph at 2.13 above was conducted for the period from 6th to 20th November 2010. This covered a full week of each pattern and is considered to be a reasonable approximation of the other twenty five fortnights in each year.
Reply: The “tidal patterns” are taken from tide predictions for 2 weeks, and not from observations, which can and do differ markedly from predictions. The 2 weeks are extrapolated to 52 weeks, and by inference to any period at all. This is considered to be a “reasonable approximation” without any justification whatsoever. Monthly data for Victor Harbor just for that year shows how wrong this “reasonable approximation” is. Other years differ from 2010 markedly. All the detailed calculations are based on the extrapolation, and have not (and cannot have) taken into account essential data on the water level inside the mouth at any time. The whole thing’s a house of cards, with the calculations as one of the bottom cards.
Compare and contrast this with
4.01 The average duration of storm surges, (i.e., the time taken for frontal systems to pass)
and their range of variation, needs additional study, as does their mean height and
their range of variation in height. Without this information the more accurate
determination of the likely range of passive flow pipe yields cannot be made.
Reply: This important and neglected factor indeed “needs additional study”, for without it the “house of cards” has one of the bottom cards removed.
2.81 Many people, including myself in the past, have criticised this evaporative loss as a
waste of fresh water which had formerly been supplied from tidal flows. But this is
based on a misconception that past sea water in tidal inflows was at the surface and
extended to cover most of the lake surface. In fact the colder, denser sea water would
have intruded under the warmer, fresh water and, even with no loss of tidal signal,
would only have extended to 30% of the lake area.
Reply: Remember his lecture at Debbie above? “Twice the prism, twice the flow”? 2.81 says that tidal influx wouldn’t even extend to 30% of the lake area. This says the exact opposite, supported by
2.36 In reality the slope of a tidal inflow is much less than half the tidal range. The natural
tidal flow has difficulty fully supplying the potential tidal prism. Flow distance is
critical. The further from the mouth the greater the variance between the potential and
the actual prism as the tidal signal gets weaker and weaker.
… which is (with 2.81) the true state of affairs, AFAIK.
2.36 & 2.81 conflict fundamentally with “increase both the volume and velocity of inflows” here:
2.83 Calls for the removal of the Barrages, including my own in the past, have been based
on the mistaken belief that this larger tidal prism would produce larger flows through
the Murray mouth that would then help maintain the mouth in an open state. But the
tidal asymmetry shown at 2.13 above makes it clear that a larger prism would simply
increase both the volume and velocity of inflows but maintain the imbalance with the
volume and velocity of outflows. The result would be an increased potential and
incidence of deposition inside the mouth.
5.44 With this direct injection of tidal water into the Coorong system the full suite of
environmental values and ecosystem services can be maintained with a substantially
higher level of certainty. And the system can be maintained in a circumstance that
remains connected too, but is no longer dependent on, the vagaries of Murray mouth
hydrodynamics.
Reply: Gobbledygook.
Most of the very few direct references used in support do not in fact support the assertion:
2.20 The maximum potential for deposition of sand within the Murray mouth is when mean sea level is highest. According to Webster (2005),
“The modelling and measurements presented by WBM Oceanics (2003) show that this transport is likely to be particularly intensive under conditions of high waves and spring tides.”
Reply: Webster doesn’t say anything about MSL in this quote, but “high waves and spring tides” – not the same thing at all, and arguably the exact opposite.
2.33 According to Webster (2005) only the long term trends make it into that system.
“Low frequency water level variations in Encounter Bay, such as those
associated with the passage of weather systems, penetrate more effectively
through the mouth and along the Coorong than more rapid level fluctuations
such as those due to the tides. Similarly, the width and depth of the mouth affect
its ability to transfer water level fluctuations into the Coorong.”
Reply: It’s perfectly clear the quote doesn’t support the assertion at all.
Included in this submission is a proposal to install a 5m diameter pipe under the dunes (the peninsula) from the sea to the lower Coorong. There is no mention of the critical factor of depth of water.
2.70 Larger Diameter Pipes will obviously deliver more water more efficiently. An
increase in diameter from 3.6m to 5.0m almost doubles the cross section but in the
tidal constraints present at the lower Coorong the volume of inflow will increase by
237%.
The maximum depth of water in the Coorong is about 5m, in the lower Coorong it is much less. Enough said, I think.
I’ll provide charts and other data of course. I’ve enjoyed this exercise. For more than a decade I was critically examining proposals to spend lots of money on schemes whose merit ranged from “clearly of benefit” to “better to dig a hole and shovel the money in”. I leave readers to judge what my assessment of Mr.Mott’s submission would have been then, and is now.
Tony Price says
BTW, Ian’s “flow rates” were based on TWO days out of the 2 WEEKS he “analysed”. What does WillyWeather (Ian’s only data source) have to say?
Tide Clock Accuracy
The online tide clock displays the current tide for Goolwa Beach as supplied by the Bureau of Meteorology using methods of interpolation and offsets provided by the Australian National Tide Tables. Actual tide clocks such as those available through the store on this website are not accurate enough for scientific purposes as they do not take into account the gravitational effects of the sun, or changes in atmospheric pressure which may alter the state of the tides. Please note that in some areas, the gravitational effects of the sun are similar in magnitude to that of the moon.
I’m currently writing a paper on “The Climate of the Murray-Darling Basin and Lower Lakes” based on two days weather forecasts for Victor Harbor in November 2010.
Tony Price says
I’ll tell you why that submission is bad to the point that it’s worthless. It contains no actual data on tides, and therefore no data on day-to-day, month-to-month, or year-to year variations. It contains no data on storm-surges other than average number and an assumed increase in water level, which even a cursory study reveals are the events which dump vast quantities of sand inside the mouth and into the channels, and not tidal flow. It contains no maps of any kind, and just one diagram, a fictional diagram of a 1km pipe stretching from well below low tide level, beneath the dunes into the Coorong, of which more later.
There are no bathymetric charts nor data of any kind. There is no account of the topography of the beach, the seabed, the dunes of the peninsula, the lakes, nor the depth of the channels inside the mouth, and most telling of all, of the Coorong, the centrepiece of the scheme. It proposes installing one or more pipes under the dunes to the Coorong with no mention of exactly where. Into the Coorong whose maximum depth is 5m over just a very tiny area. Pipes up to 6.4m bore into the Coorong which is typically 2-3 metres deep over most of its area, and down to a few cm in places. Pipes which would consequently have their “non-return valves” (not described nor costed in any way) half-buried in the bed of the lagoons.
There’s an almost anal obsession with minutely detailed but fictional flow rates through the pipes. Fictional because the difference in head of water driving the flow is calculated from an idealised tidal pattern which applies to hundreds of km of shoreline and not from real data for the locality; a head of water which is calculated assuming no change of level inside the Murray mouth, the channels or the Coorong as the inward flow progresses, when of course the head of pressure decreases as the levels inside increase, decreasing the flow. Fictional because the flows are calculated for only two days tide pattern in November 2010, with the assumption that the calculated mean sea level for those two days applies not just to the rest of the month, but to any period, when the actual monthly average sea levels vary over a range whose maximum is 50% greater than the calculated MSL, and whose minimum is 20% less.
Because there’s no topographical data on the shallow-shelving beach, the proposed length of pipe(s) would be far too short; waves can be seen breaking as much as 4-500m out to sea on air photographs and Google Earth/Maps, which means that the seaward end of 1km-long pipes would likely be breaking the surface at neap tides, certainly so if they were 6.4m in diameter.
There’s an assumption (most of the document is assumption) that tidal flow through the mouth takes a significant amount of sand with it, when there are smooth sandbars and sandbanks and sand islands inside the mouth and channels. Sandbanks and sandbars which aren’t covered even by high tides; sand islands which aren’t covered by any tides. Clearly none of these got there by tidal flow; neither water nor sand flow uphill. Not none of them will be removed by reverse tidal flow nor river flow through the mouth. The action of river flow is to scour the mouth; river flow can’t lift sand from the deeper channels and push it over the rock/sand bar at the mouth. River flow is too slow to scour much sand from the bars and banks, and even if it does, it’ll just be moved a short distance closer to the mouth.
Clearly, under normal tidal conditions there’s a near equilibrium set up. – some sand sand comes in with the tide, rather less sand goes out with the tide. Normal tidal flow doesn’t shift much sand; if it did there’d be sand piling up daily on the beaches all along the peninsula. Storms shift sand through wind and wave action and much higher sea levels due to the combination of wind and low atmospheric pressure. Storms have created the sandbars and banks and islands, and the bordering dunes themselves. A 1-millibar (hPa) reduction in pressure causes a 1cm rise in sea level. Reductions of 10-30 hPa are common during storms, possibly more during full-blown tropical storms.
There’s a statement to the effect that additional river flow provided by releases of (valuable and expensive) fresh water won’t shift much sand (I’d say virtually none), and that the effect will be to do little more than scour the mouth (without once using the word “scour” anywhere). and widen it, and that this will make the mouth more prone to sand influx during storms. I accept this in the absence of contradictory evidence, it seems perfectly logical. What I don’t accept is that additional flow out through the mouth, as a consequence of introducing more sea water through pipes, and therefore over longer periods than currently will not do exactly the same and to a greater extent – widen the mouth and make it more prone to sand influx during storms. This is entirely overlooked in the justification, it can’t be denied, and is a serious flaw.
Many statements, assertions and conclusions contradict one another throughout. The few references used to “support” some conclusions do not in fact support them, as I mentioned in an earlier comment. Worst of all, there’s a whole section at the end which details much additional data which is needed to make a proper job of it, most of which I’ve mentioned above as missing entirely. You can’t make bricks without straw, and you can’t produce a detailed submission without essential facts and data.
Ian Mott says
The clown who seriously claimed that a larger prism wouldn’t influence the velocity of tidal inflows now runs a desperate attempt to cover his tracks with his standard search for anything he can first misinterpret, and then shoot down his own misinterpretation. But I guess that is the only way such a conspicuous plodder can fabricate a win.
The real classic is he then goes through the section of my submission called “4.00 What else do we need to know?” and then ponces about presenting the same issues as if they were omissions on my part that HE had actually discovered. What a troll.
Readers of that submission who have had officer training will recognise a format similar to what is called a battlefied “appreciation of the situation”, the core of any plan, which sets out, among others, essential facts, assumptions, unknowns, alternatives etc. Those with exposure to the planning processes covered in MBA courses will also recognise a familiar format.
And if Price had ever had any exposure to a proper planning role himself, he would also know that any plan should be a work in progress which allows for constant revision and addition of greater detail.
And given that Price is such an expert on MDBA submissions perhaps he would care to provide a link to his own submissions to the MDBA to compare the level and adequacy of his data. Indeed, take a look at Jennifers own work and see who is laying out information to inform and who is flogging spin based on anecdotal references out of context.
And then he has the gall to suddenly discover the relevance of differential water levels after being found to have completely ignored it, no actually rejected its relevance, in an earlier post. I will copy his pathetic post above and reply in detail on my own blog. This doofus is obviously trying to generate some traffic to his own site but I refuse to oblige. But rest assured, the more this clown tries to burrow into the detail the bigger fool he makes of himself. So go ahead, punk, make my day.
Ian Mott says
Ah, it all makes sense now. I was under the impression that Price was from some sort of honourable profession like farming but the reality is that he is nothing more than a pensioned off departmental boofhead. And what readers have been given is a very good example of the way bureaucratic low life can breach the trust placed in them and abrogate their duty to consider all issues in good faith.
He claimed he “knew a bit about tides” but then proceeded to claim that a larger tidal prism would not produce faster tidal flows through the same channel.
He had no idea how a pipe could allow water to flow through it without bringing sand with it, but instead of asking, he listed it as a flaw in my logic.
He had no idea how to make a simple one way valve on a pipe, but instread of a asking, he listed it as a flaw in my logic.
He favoured a flow that went the other way, ignorant of the fact that such a passive flow could only work during the lower half of the tide cycle, and not at all during storm surges, and could only then result in a substantial lowering of the Coorong’s water level.
He has no idea why a continuous inflow of sea water will NOT lead to a major increase in Coorong water level that would impair the efficiency of pipe flows. But instead of asking, or even reflecting on it for a few minutes, he listed it as a flaw in my logic.
He has no idea how a 5m diameter pipe could flow into a water body that is only 2m deep. But instead of asking how, he listed it as a flaw in my logic.
And he has no idea of the concept of opportunity cost, that the upper limit of what could be spent to keep the mouth open with sea water would be the value of the fresh water they wish to buy back and the value of the losses such a buy-back would inflict on the basin community. But instead of asking, the dumb turd listed it as a flaw in my logic.
Price never intended to consider anything I have said with an open mind. His selective quoting out of context and deliberate misintepreting to produce straw men is as painfully obvious as it is tediously repetitive. I don’t intend to redress any further gaps in his knowledge because he needs to place the full sum of his ignorance on display for all to see before any further response. Educating the village idiot can only end in tears.
And as for the merit of my submissions, they have clearly been intended to serve two purposes. Firstly to inform the policy process on an issue that has not had proper consideration. And secondly to provide sufficient understanding of the need for further investigation. But this bile soaked nutter then has the gall to complain that my pro-bono efforts do not meet the standards of a full engineering feasibility study, the cost of which would leave little change out of a million bucks.
Readers will now have noticed how Jennifer has consistently declined to substantiate any of her assertions. Does she agree with Price’s penetrating insights into flow rate responses to larger tidal prisms?
Is she prepared to explain to us how large waves behave when they enter an estuary? Or is she still claiming that there is no change from the way large waves behave when they hit a beach?
Is she prepared to enlighten us with her own understanding of how river outflows alter sand deposition volumes?
Or will she continue to avoid any statement that might tell us all what little she actually understands and how callously she disregards any evidence that challenges her ignorant whimsies.
Tony Price says
As usual, Ian uses the weapons of the intellectually barren to attack the messenger first, and then attack what they didn’t say second, and produces “straw men” from his hat with a wave of his wand.
Here are a few examples from his last comments:
“He has no idea how a 5m diameter pipe could flow into a water body that is only 2m deep. But instead of asking how, he listed it as a flaw in my logic.”
Why should I ask how? The onus is on the author of a proposal to utilise pipes to explain it, and in the proposal, not in a blog thread. Whether it’s a flaw in his logic or not, it’s a glaring omission in his submission.
“He had no idea how a pipe could allow water to flow through it without bringing sand with it, but instead of asking, he listed it as a flaw in my logic.”.
I indeed do, as with power stations’ water inlet pipes, but it shouldn’t be up to me, or any reader of his submission to provide a solution, but the author of the document, something he’s signally failed to do.
“He had no idea how to make a simple one way valve on a pipe, but instead of a asking, he listed it as a flaw in my logic.”
I indeed do, but not with pipes up to 6.4m diameter, where the valves or flaps must needs weigh many tons, and be a costly component of the installation. It shouldn’t be up to me, nor any reader of his proposal to know how to scale up a “simple valve” to the size and weight implied, but for the author of the document to know it, to explain it and equally importantly at least have a stab at the design and likely cost, which things he’s signally failed to do.
“Is she prepared to explain to us how large waves behave when they enter an estuary? Or is she still claiming that there is no change from the way large waves behave when they hit a beach?”
Ian hasn’t explained or quantified this anywhere, yet challenges someone else to do so.
“Is she prepared to enlighten us with her own understanding of how river outflows alter sand deposition volumes?”
Ian hasn’t explained or quantified this anywhere, yet challenges someone else to do so.
If someone’s intending to identify an engineering solution to an environmental problem, it might be expected that that person display some knowledge of, and some skill in, both disciplines. Ian has displayed little of either in both. I say displayed advisedly, as he’s clearly no “vacuous moron” as he described me, but the “vacuous” part applies as he leaves us in the dark, to ask questions about the detail.
He didn’t know that the WillyWeather tidal predictions (produced using a computer model) were actually for Victor Harbor. He didn’t read the warning there that the data there wasn’t “accurate enough for scientific purposes”. He chose to use data for only 2 days out of 365 to calculate flows, and to effectively extrapolate his calculated flow rates over a full year, when the period he chose doesn’t represent that year, let alone any year.
He didn’t show any bathymetric (depth) data for the mouth or channels, lakes or lagoons, or the very relevant seabed , something that would be considered to be essential for a scheme which proposes to pipe water from some distance out, above that seabed, and into the watercourses.
He didn’t even attempt to analyse the direct consequences that an injection of sea water into those watercourses would have (not even their levels), something that would be considered to be essential for such a scheme. In his flow calculations, he implicitly assumed no change in level in those watercourses, a major error, as such an increase in level reduces flow as it proceeds.
He finishes:
“Or will she [Jennifer] continue to avoid any statement that might tell us all what little she actually understands and how callously she disregards any evidence that challenges her ignorant whimsies.”
Ian says “instead of asking” a total of 5 times here. He has written a proposal, which purports to be a detailed solution to a problem, and leaves the reader to ask important questions not answered therein? Ian has the “don’t ask it’ll work fine when we do it and any problems can be solved along the way and by-the-way we haven’t costed it” approach of the simplistically minded to geo-engineering “solutions”.
Ian has displayed in all that he’s written here, on his blog, and in his submission, how little he actually knows, or at least is prepared to tell us, for he tells us very little at all of substance, and leaves us to ask questions instead. A solution is supposed to answer questions, or at least to suggest answers.
Tony Price says
I’ll be updating my “Murray mouth” post with bathymetric charts and links, and anything I consider relevant later today, for example the significant effect of barometric pressure on sea level. I’ll then restructure it with inline links to sections, links to other sources, rename it and elevate it to a fixed reference page linked at the top of the sidebar. It should prove to be a useful resource as it grows. If you have any suggestions for content, please leave them here, or better, on the response thread (or both, if you have the time and inclination):
http://mostlyharmless-room-101.blogspot.com/2012/05/australia-murray-mouth-effect-of-tides.html
Ian Mott says
Price is still clutching at straws with what he thinks is a relevant argument about the difference between Willyweather and the BoM data for Victor Harbour. But the reality is that the scale of storm surges on inflow volumes, when applied to a full month of tide values, (not 2 days, doofus)and applied to only the period when tide was above the AHD level of the South Lagoon, was found to increase total flow volume by 50% for an assumed storm increment of only 20cm.
This was why I identified the need for more detailed examination of the full range and frequency of actual events in the section “4.00 What else do we need to know?”
The submission made it ABSOLUTELY clear in the 1.0 General Principles section that the proper exercise of power by the MDBA went beyond the mere consideration of matters raised. It also extends to conducting proper (ie more detailed) examination of any relevant matters it may become aware of. It never set out to be a complete report, and at no stage have I ever held it out to be such a definitive statement of fact.
And Price is not acting in GOOD FAITH by suggesting that this invitation for the MDBA to further examine a relevant matter had an obligation to be 100% accurate. Has this goon seen the entire page of disclaimers that normally prefaces CSIRO reports that have had the benefit of substantial funding and major in-house resources?
Indeed, given the disparity between Jennifers claims of 1 million megalitres of saved evaporation from Lake Alexandrina and the squalid reality of zero savings while ever annual river flows exceed a very modest 600,000 ML, it is clear that Price is a first class hypocrite.
More importantly, a firm calculation of the actual volume of inflows through pipes is far less relevant than the fact that inflows will vary to match whatever tide maximum occurs on any day. The higher the tide peak the greater the difference between outside and inside water levels and the faster the flow will be in response. Once again, Price thinks he is on to a critical point but the reality is that he is only up yet another blind alley for the ignorant.
And the fact that his only recourse, in filling in the gaps in his understanding of the issues I pointed out in previous posts is to demand that I enlighten him, only highlights how out of his depth he really is. I have no problem explaining, eventually, but only after this goon has shown us all a clear record of what he thinks is the case. Price has a date with his own stupidity and I want a permanent record of that stupidy. So go for it, doofus.
The irony is that local MP for the region, Patrick Secker, on hansard for the Windsor Committee, estimated the cost of a pipe to be only $30 million each. I made no cost estimate of my own because I am not an engineer. But even if Secker is out by 100% and each pipe costs $60 million, they will deliver the same 3 million megalitres of sea water a year in perpetuity for $180 million that the MDBA already has a budget to deliver intermittently with $6 Billion worth of buy-back water.
And this Price (Prize) freak show has the gall to work himself into a lather over the variance between Willyweather and BoM tide records? Talk about lost the plot.
Tony Price says
I like this game, the more I look the more I find – I spotted this one a while ago, but kept it in reserve. Since you mentioned both Jennifer AND evaporation:
2.48 The North Lagoon is 48km long. Its average width at AHD is 1.5km, depth is 1.2m, surface area is 7,200ha and volume is 86,400 ML (CFMI , 1992). Mean annual pan evaporation is 16 ML/ha so the actual (80%) is more like 12.8 ML/ha. Mean annual rainfall is 5 ML/ha giving a net evaporative loss of 7.8 ML/ha. It requires an average 56,160 ML each year (65% of volume) to replace net evaporation losses.
SFSG (so far so good) Mean annual rainfall is 5 X 7,200 = 36,000 ML (remember this figure), net evaporation loss (evaporation – rainfall) = 56,160 ML.
2.57 When the historical average 77 annual storm events were included, at an assumed median height increase of 20cm and of 24 hour duration, the total annual inflow was estimated to increase by 25% to 228,200 ML or an average 625 ML/day.
2.58 Add the mean annual rainfall of 36,000 ML and the total water increment would be 264,200 ML/year. Deduct the evaporation loss of 56,200 ML and we are left with a minimum net injection of 208,00 ML each year, or a 240% turnover of the original volume. These 2.4 complete exchanges of volume each year will deliver in full, and well, the ecosystem services that a much larger volume of fresh water spilled over the Barrage does only partially, intermittently, and poorly.
… but the evaporation loss of 56,200 ML (56,160 ML in 2.48) has already taken rainfall into account, it’s a NET evaporation loss. Ian’s added the rainfall in TWICE.
No wonder Ian had a go at Jennifer over evaporation as opposed to net evaporation figures. If she’d added it in ONCE, it wouldn’t have been enough for him.
Tony Price says
Since you mentioned AHD, ” the period when tide was above the AHD level of the South Lagoon”, you don’t know either of these, that is the level wrt AHD of the surface of the South Lagoon, nor (more importantly) how tide-gauge zero and therefore tide height relates to AHD. It’s clear from your assumptions that you don’t. If you do, explain for all us “doofuses”.
Peter R. Smith – OAM - Mannum says
Hi all,
The article that began this thread was in reference the Lakes Alexandrina and Albert and is COMPLETELY separate from the Coorong.
The problems in Coorong are caused by circumstances and just for readers information most experts on the Coorong (I am not totally versed on the Coorong) believe the Southern Lagoon should be pumped out so therefore totally devoid of hyper-saline water and the height should be maintained at approximately +0.3-AHD.
Ian Mott says
Thanks Price, you have finally identified a valid error, for which I have no problem with thanking you for identifying it. The deduction, that applies only to that particular part of the analysis, should have been the gross evaporation, not the net. And the implications are that the particular pipe dimension’s inflow would replace the entire volume of the North Lagoon 1.99 times each year instead of 2.4 times. And note that this was a hypothetical case using a smaller pipe to illustrate the point. The recommended larger pipe would introduce more than a million megalitres a year, rendering that error irrelevant.
The more important point is that Jennifer left out all mention of rainfall or net evaporation altogether and not only did none of her acolytes say a word about it, they sat by passively while she attempted to excuse her gross omission of an essential fact.
Re pumping out: The budget for a single pump-out of the South Lagoon is over $39 million which will bring salinity levels back to that of sea water for just a few years. The infrastructure will then sit completely idle (and uncosted) until it is needed again. The Ngarindgerri have stipulated that the pipe for pumping cannot be burried due to concerns over disturbance to ancestral burial sites.
But this does not preclude the use of pipes for passive inflows because the option works equally well, and much cheaper, if the pipes operate on a syphoning basis. I opted for burrial of the pipe out of an assumed primary visual concern. But as long as the ocean entry and lagoon discharge points remain lower than MSL then the passive inflow during high tides will continue. I do hope that Price actually understands the concept of syphoning.
Ian Mott says
So eager is Price to find any pretext to criticise that he would now like readers to believe that the annual variations either side of mean sea level are of such significance as to render the general calculations of inflow above AHD invalid. So once more for the plodders, these are the minor nuances that a fully funded feasibility study would add to the picture. And given the variances between the $6 billion cost of buy-back fresh water and the $60 to $90 million cost of pipes for sea water, this minor nuance in flow volume is totally irrelevant.
The same applies to Price’s red herring about raised internal water levels as a result of the piped inflows. That would only be a factor if the Coorong was a closed system that prevented water from flowing north to the murray mouth.
Note also from his site, how the only tide graphs he shows are for April/May 2012. This just happens to be during an atypical Perigee, the one period in more than a decade when tidal range and heights are most pronounced. Good one, scrubber, really representative.