Could we make that flood worse?

Many landholders along the Tumut River have not returned to their homes because of increased outflow from the Blowering Dam. (AAP: Wolter Peeters). From the ABC site.

It’s not like we need another case study in just how creatively dumb bureaucracy can be, but Jennifer Marohasy has been relentless in pursuing the extraordinary case of a government contracting a corporation to pour nearly 7000 Mega litres into a area facing life threatening floods. That’s more than 2000 Olympic pools worth of water dumped into a flood zone just last Wednesday.

Remember, this legislation was made with good intentions, and it was supposed to help the environment…

The Whole Truth: Water Deliberately Dumped into Flooded Area

SNOWY Hydro chief executive, Terry Charlton, recently confirmed that water was dumped into the already flooded Murray-Darling Basin, but said the authority had little choice (The Australian, December 15, 2010, page 7).   A real time operational diagram, however, tells a very different story.

Last Wednesday, Snowy Hydro could have sent water into Eucumbene dam.  At only 20 percent it had a storage capacity of a whopping 4 cubic kilometres of water.

Instead, the water managers set the trans-mountain tunnels so water was flowing away from Lake Eucumbene at over 80 cubic metres per second (6,912 megalitres for Wednesday).

Tumut River residents were issued with urgent evacuation orders last Thursday after the increase in outflows.

Desperate farmers phoned Snowy Hydro last week asking why flood waters were being sent west, rather than east to Lake Eucumbene, given this dam was less than half full, but their calls were ignored.

Read more…

Killing tadpoles for the sake of bureaucracy

The water is being removed from one place where it could be useful to go to another where it’s desperately not needed.

ANGLERS fishing Lake Eucumbene in late October 2010 were pleased to see that the rising waters of the lake had created perfect spawning conditions for the frogs.

Frogs were in abundance and their future was assured through this massive spawning event, or so we thought.

Lake levels started falling even though the state was flooding?

More importantly anglers watched as the frog spawn was left high and dry.  The baby tadpoles yet to hatch suffered a miserable death by dehydration.  Caring anglers scurried around the lake margin; lifting spawn blobs and putting them back into the water, only to see the whole miserable cycle continue as the waters relentlessly receded.

How many frog larvae died we will never know, but the receding waters killed far more frogs than any number of trout possibly could – even the deadly chytrid fungus would have been hard pressed to match this slaughter.

Read more…

Ross Tyson sums it up:

“AN ARCHAIC agreement hatched in the air-conditioned suites of a Sydney office block has exposed the kind of chronic mismanagement at government level that is driving local farmers to the point of despair.

“The revelation this week that Snowy Hydro is sending millions of litres of water downstream every day into overflowing dams and flood-affected towns along the Murrumbidgee River has left irrigators dumbfounded.

Read more of the Area News Story at Jennifer Marohasy’s site

The Government only had 8 months warning

Back on Dec 14th the CEO of the Snowy Hydro was frustrated that he’d warned the NSW government in April that this could happen:

Snowy Hydro Wants Changes to Licence Provisions to Avoid Exacerbating Flooding

“The NSW government appears unable to make any decisions,” said Mr Charlton.

“The situation is ridiculous.  We are frustrated.   Late last week we pulled back on the water releases but this potentially puts us in contravention of our water licence,” said Mr Charlton.

Those details…

Jennifer Marohasy has been doing a great job. Isn’t this the kind of research that paid journalists are supposed to be doing?

Spinifex Computing is a supporter of this site. If you are a Unix or Linux developer, install small VOIP systems, are looking for a data logger, or a low power network storage provider, Spinifex might have just what you need. Plug computers have taken off in the EU and US, but are just being discovered in Australia. Why not pop in and find out more about the plug craze?
7 out of 10 based on 3 ratings

55 comments to Could we make that flood worse?

  • #
    Iren

    This should have been on the front page of every newspaper days ago.

    I actually sent a link to Jennifer Marohasy’s article to the Daily Telegraph earlier in the week but they were more concerned with Oprah at the point.

    10

  • #
    Rereke Whakaaro

    This is the New South Wales State Government – a bureaucracy in which collective responsibility is the norm – everybody is responsible, so nobody is actually answerable.

    This is a good example of the level of mediocrity that spontaneously appears whenever five or more bureaucrats have to work together or communicate on a common problem. I have observed it many times, in different organisations, in various countries. Decisions just don’t get made, or if they are, they get re-litigated to the point where everybody looses interest.

    I have no hypothesis regarding the causation, but the observations seem to be consistent. “Five” appears to be some form of tipping point.

    10

  • #
    Baa Humbug

    I’ve followed this story at Jennifers for a while now.

    As much as it’s a story of bureaucracy gone mad, it’s also a story of public servants cowering.
    Public servants who know a terrible thing is happening just turn a blind eye and say “oh well, I followed the regulations.”

    There was a time when public servants could do their job without fear or favour. Now they just serve their current political masters, whomever they maybe.

    Mr Charlton should have continued to pull back on the water release and possibly caught up at some stage later.

    So I would ask him, what if people had died downstream?

    Apparently the NSW Govt. will revisit the agreement, effectively admitting the original agreement was lacking. Isn’t that so typical of today, always shut the barn door after the horse has bolted and never ever take responsibility.

    A pox on all their houses, each and every one who was involved.

    10

  • #
    Rereke Whakaaro

    Off Topic, but interesting …

    This post at Bishop Hill carries a comment from “ManiacBeancounter” that I thought summed up the status of the debate quite nicely:

    The theory that greenhouse gases will cause the earth’s average temperature will [to] rise markedly, with catestrophic (sic) consequences, requires a number of “heroic” and unverified assumptions. If you open up doubts, then the compound effect will be to conclude that the worst fears are highly unlikely, and current policies will be of virtually zero benefit, but with huge economic costs. That is why no middle ground, or debate of the issues, can be countenanced.

    It certainly explains why the bureaucracy and the MSM have been “encouraged” to march in lock-step.

    10

  • #
    JPA Knowles

    I’ve been a bit painfull as a long time NRMA Insurance customer and share-holder and written to them asking them to investigate the issue. Somewhere down the track I might be paying larger premiums to cover the pay-outs of this flood which was exacerbated by Snowy Hydro and incompetent Government. Surely the smart thing to have done would have been to store as much water as possible and let it out after the rain flood.

    10

  • #
    Joe Lalonde

    Is the government so desparate to create employment that they helped to generate this disaster?
    Ops, sorry I had forgotten…AGW is to be blamed.

    10

  • #
    Baa Humbug

    Our policy makers are getting some terrific advice (sarc) from that bastion of knowledge, the formerly great CSIRO.

    Via Andrew Bolt and The Australian.
    Seems the CSIRO fudged field trials to deter the State and Federal Govts. from seriously considering computerised fire detection technology. And this after the deadly Black Saturday bush fires in Victoria.

    Makes me wonder what their beef is. Could it be that these technologies were developed overseas and not in Oz?

    Any CSIRO employee who has knowledge of this story is welcome to post a comment and set the record straight. They are losing what skerrick of credibility they may have left.

    10

  • #
    Jeremy

    “The marvel of all history is the patience with which men and women submit to burdens unnecessarily laid upon them by their governments.”
    — George Washington

    My full apologies to the Thompsons, I had shamefully forgotten these words.

    10

  • #
    Roy Hogue

    Public servants who know a terrible thing is happening just turn a blind eye and say “oh well, I followed the regulations.

    Baa,

    Exactly why laws, rules and systems never work. No one is ever empowered to actually think about what’s going on at any given moment and make good decisions. If you have a rule to follow you don’t have to stick your neck out by making a decision and risk any criticism from the boss.

    10

  • #

    Roy Hogue @9: No one is ever empowered to actually think about what’s going on at any given moment and make good decisions.

    There is good reason for this. To be “empowered” to do something means you have permission to do it from a higher power. Thinking about something and making good decisions is something that cannot be done by permission. It results from a life long intellectual and mental discipline with a foundation of absolute honesty about what YOU known and what is possible based upon that knowledge. If you have not been doing it since you were a young child, being allowed/required/commanded to do so by that so called higher power, you cannot do it. If you have, you do not need permission from that higher power. You will do it by habit. The higher power is irrelevant to getting positive results in any situation. ALL the higher power can do is stop the individual from acting based upon his thinking.

    This is the primary reason why the so called higher power’s only effective action is stopping foreign aggression and internal violation of rights. Any other activity will, by the basic nature of all parties involved, will be inefficient, ineffective, and ultimately a dismal failure even by the standards of the higher power. Unfortunately, this is exactly what some higher powers like. It gives them an excuse to do more of the same in an endless cycle of growth following failure which is in turn followed by still more failure followed by still more growth.

    A discussion of the mechanism that assures the above cycle of failure is beyond the scope of a single post. It is not that we don’t elect good enough people to office, its that the fundamental nature of reality, man, government, and rule based systems is such that it is all that can happen. That is unless and until government (the universal higher power behind this discussion) is successfully limited to only the stopping foreign aggression and internal violation of rights, overgrowth of government and the ultimate consequential collapse of the society under its power is assured.

    10

  • #
    MadJak

    This situation disgusts me.

    You’ll here me suggest this again in the future, and hopefully from others….

    If employees are subject to random drug testing, so should anyone in the pay of the public purse – bureaucrats, beneficiaries, politicians, the whole lot. If taxes pay for your wages, you should be subject to random drug tests. If found to have illegal substances in your system. Goodbye.

    Maybe this would result in less stupidity, although I think Rereke is right, five is a magic number – De Bono alluded to it.

    10

  • #
    Amr

    Great article but you last sentence is what is a great laugh;

    “Isn’t this the kind of research that paid journalists are supposed to be doing?”

    What a rhetorical gem?
    Amr

    10

  • #

    MadJak @ 11: five is a magic number

    Yes it really is. In any team effort requiring rapid and coordinated adaptation to the actual situation, a team of four is slightly less effective than a team of one. Go beyond four and the ability of each to communicate to each drops rapidly.

    For a fully connected network of active nodes there are n(n-1)/2 communication paths. See: http://en.wikipedia.org/wiki/Network_topology

    nodes = 1; paths = 0; communication overhead per node = 0.0
    nodes = 2; paths = 1; communication overhead per node = 0.5
    nodes = 3; paths = 3; communication overhead per node = 1.0
    nodes = 4; paths = 6; communication overhead per node = 1.5
    nodes = 5; paths = 10; communication overhead per node = 2.0
    nodes = 6; paths = 15; communication overhead per node = 2.5

    notes = 35; paths = 595; communication overhead per node = 17.0

    As you can see, the communication overhead of each node grows with each added node. Eventually more time is spent communicating (aka having meetings) than is spent on doing actual work to get real results. Hence the larger team is limited to action by rule or command rather than knowledge and thoughtful analysis. Reality rapidly diverges from the rules thus making the rule based activity ineffective and ultimately a failure.

    My experience indicates the breaking point of a fully connected network team is a team of four. Beyond that, if real work actually gets done, there is a core group of four who produce the results. The remainder of the team are little more than dead weight having meetings and consuming scarce project resources. They contribute nothing to the final outcome of the project and very often seriously degrade the possibility of project success.

    This is why almost all large projects tend to have meetings consuming almost all the time and resources available for getting work done. It is also why, large projects tend to go over schedule, over budget, and fail to deliver as promised. Some (most?) of them wildly so.

    What does this say about our largest project, the government?

    10

  • #
    MadJak

    Lionel,

    You’re preaching to the converted there mate. my experiences are very similar. Interestingly it is what Moltke referred to as friction. The more people involved the more incompetent the system becomes unless central control is delegated more so well informed front-line personnel can make the right decisions ( and be held accountable for them).

    With this situation, what was blatantly obvious on the ground was obviously far to complex for the command system to comprehend, let alone handle.

    10

  • #
    Another Ian

    More people should read the book of “Parkinson’s Law” IMO

    10

  • #
  • #
    Ray Hibbard

    Don’t know much about Australian jurisprudence but wouldn’t your insurance companies have a claim against the government in this case.

    10

  • #
    Siliggy

    Releasing large volumes of water into a flood is not just insane it is criminally insane. Did people who are well educated about the risks involved with letting water out at a fixed and dictated amount not take variation of rainfall into account? Really? For a license agreement like this to be reached and become binding on fixed quantities someone had to deliberately ignore a vary basic and obvious variable.
    Did they even consider the possibility that it may rain?
    Frogs killed, water wasted, farms and the food supply damaged, lives threatened and property (gov’t and private) sabotaged by vandalistic adherance to red tape.
    This crime is sabotage!
    The military were involved in fighting against this flood so the actions of making the flood worse were actions against our military also.
    In my view the ones who are guilty of this sabotage are the ones who said:
    “Australia may be facing a permanent drought”
    The intent of this sabotage may have been “the destruction of agriculture in Australia’s main food bowl.”
    http://www.newsweekly.com.au/articles/2003sep06_w.html

    10

  • #
    Bulldust

    The following piece is well worth a read. Michael Aston argues for climate science to be pulled out of the political arena and placed squarely back in teh scientific domain at The Australian:

    http://www.theaustralian.com.au/news/opinion/political-interference-will-cripple-climate-debate/story-e6frg6zo-1225972366783

    It is clear that he would be rated a skeptic or at least luke warmer, which is hardly surprising given his geologist background. I applaud his restraint in admonishing the politicos that interfere with the scientific process, funding and reporting.

    10

  • #
  • #
    wendy

    NOAA & NCDC Pursue Goal of ‘Warmest Year Ever’ For 2010 – Release Newly Fabricated Global Temperatures!!!!!!!!

    MORE AND MORE FRAUD!!!

    http://www.c3headlines.com/2010/12/noaa-ncdc-pursue-goal-of-warmest-year-ever-for-2010-release-newly-fabricated-global-temperatures.html

    10

  • #
    val majkus

    I’ve been following this story at Jennifer’s blog and at Online Quadrant for some time.
    It’s made me think that we’re so lucky to have people with the persistance and patience that Jennifer, Jo, Warwick Hughes and other independent and open minded experts display all of them giving us space on their blogs for comment good and bad.
    Don’t forget to buy Jo some chocolate for Christmas, she deserves it for the unpaid lonely hours at her keyboard educating people like me and giving us a supportive forum.
    Thanks Jo, Jennifer, Warwick and all the other experts I know and love and whose blogs I frequent and may you Jo get plenty of chocolate for Christmas!

    10

  • #

    I nearly fell off my chair laughing when I read about this a few days ago. Those wacky climate scientists are aided and abetted by two groups of people: useful idiots in the media and useless idiots in government.

    10

  • #

    Here was the tip off, of course:

    I love a sunburnt country,
    A land of sweeping plains,
    Of ragged mountain ranges,
    Of drought and flooding rains,
    I love her far horizons,
    I love her jewel sea,
    Her beauty and her terror
    The wide brown land for me.

    10

  • #
    pat

    california has adopted capntax today and, in the UK, it’s an equally bad day. huhne below shills (dishonestly, of course) for the financial bubble which is to replace the sub-prime bubble, the internet bubble and the rest of the bubbles that no 24/7 news channel will ever call a bubble, much less warn about in advance. and the non-business channels will do no better.

    but hey, there are over 9.500 news results on google’s main page today on assange. assange, who is not a whistleblower but merely hosts a website which coordinated – with the same MSM who push CAGW – the publication of some cherry-picked cables allegedly from a massive cache allegedly leaked by US soldier, bradley manning. those released tell us nothing we did not already know and may not even be from those released by manning.

    meanwhile manning remains in jail, in terrible conditions, while his supporters (very few) have not received the money allegedly pledged for his defense by wikileaks:

    9 Dec: Age: No WikiLeaks funds to pay for leak suspect’s defence
    WIKILEAKS has yet to make good on a July pledge to contribute to the legal defence fund of a US Army private suspected of leaking classified documents to the site, the fund’s director said on Tuesday.
    ”It’s a surprise to us that it hasn’t happened yet,” said Jeff Paterson, project director of Courage to Resist, a group seeking to raise $US100,000 towards legal fees for Bradley Manning (right), who was charged five months ago in connection with the leaking of classified material.
    Courage to Resist, a war resisters’ group, has donated $US50,000 to pay the fees of Manning’s lawyer, David Coombs. But as of Tuesday, Mr Paterson said, WikiLeaks had not transferred any money to him…
    In London last week WikiLeaks spokesman Kristinn Hrafnsson said the group had contributed to Manning’s defence fund ”a substantial amount of money,” while insisting WikiLeaks still did not know whether he was the source of the diplomatic cables and other classified material it recently posted…
    http://www.theage.com.au/national/no-wikileaks-funds-to-pay-for-leak-suspects-defence-20101208-18ps8.html

    yet, the public at large remains completely unaware of which websites published the Climategate emails/computer code and no-one in officialdom or the MSM wants to know if they were released by a whistleblower or, as they like to say, stolen.

    yet the contents of the Climategate emails/computer code destroyed the CAGW fantasy which affects every single human being on earth in a financially negative way!

    16 Dec:UK Telegraph: James Delingpole: Huhne: the final nail in the coffin of Cameron’s lousy Coalition?
    (Chris Huhne) By providing greater certainty, we can encourage new market entrants and investors, reduce the cost of capital, and provide low-carbon electricity at lower cost than under present policies. Our mix of four inter-locking policies should give greater assurance of decarbonisation and lower bills…
    http://blogs.telegraph.co.uk/news/jamesdelingpole/100068571/huhne-the-final-nail-in-the-coffin-of-camerons-lousy-coalition/

    there will be no protests on the streets, because the CAGW fanatics, with their celebrity chorus, still have the majority of that demographic under its spell.

    10

  • #
    cementafriend

    Joanne, someone with legal training should look if Snowy Hydro and some NSW government officials have breached NSW Public Service laws and the code of conduct of Public Agencies. Queensland has the Public Sector Ethics Act (1994). The Act says it binds all persons including the State. My reading of the act is that such as an occurance as you describe would be in breach of the Act. NSW has a different act (Public Sector Employment & Management Act 2002) which I think covers areas of ethical conduct towards the public. I understand there is also a Moral Code of Conduct of NSW Public Agencies which could be like a regulation under the Public Sector Act. The public sector is becoming politicised. Someone needs to take them on. A stretch in jail for those in breach might show the rest of the public service where there primary duty lies.

    10

  • #

    […] This post was mentioned on Twitter by Robert J, Tele Vision. Tele Vision said: Could we make that flood worse? « JoNova http://bit.ly/hBnmdt […]

    10

  • #
    wendy

    Subject: BIG BROTHER COMES TO COFFS HARBOUR!!

    http://www.coffsharbour.nsw.gov.au/www/html/5361-cancer-councils-sun-sound.asp

    Cancer Council’s Sun Sound

    Music is being used to help save lives on the Coffs Coast with an innovative jingle penned by acclaimed musician Ben Lee.
    The catchy Sun Sound is being trialled at Park Beach in the hope that it will help combat the 250 people diagnosed with melanoma on the Mid North Coast every year. It is an initiative of the Cancer Council NSW.
    Sun Sound will be played on loud-speakers every two hours reminding people to protect their skin with hats, sunscreen, sunglasses, clothing and shade.
    =======================
    HOW MUCH IS THIS COSTING??
    WHAT’S NEXT, CAMERAS TO RECORD WHETHER PEOPLE OBEY THE COMMAND?
    PENALTIES FOR NOT OBEYING??
    BANNED FROM THE BEACH FOR NOT COMPLYING??
    FENCING OFF THE BEACH AND NO ADMITTANCE IF YOU HAVE BEEN FOUND TO BE GUILTY OF NOT COMPLYING WITH THE COMMANDS BROADCAST??
    WELCOME TO GEORGE ORWELLS 1984 IN 2010 IN COFFS HARBOUR, AUSTRALIA!!!!!!!!!
    HOW LONG DO YOU THINK THIS SPEAKER WILL LAST BEFORE IT IS DESTROYED BY THE LOCALS?????????
    PITIFUL THAT THEY THINK THAT PEOPLE CANNOT TAKE RESPONSIBILITY FOR THEIR OWN ACTIONS!!!!!!!!
    THE F..KING NANNY STATE!!!!!

    Honestly, it seems to me that these people would simply DIE if somebody didn’t keep reminding them to BREATHE!

    10

  • #
    Another Ian

    Re Wendy #27

    Careful now!

    “michel says:
    December 17, 2010 at 2:29 am
    Interesting to see that another hysterical use of the precautionary principle just bit the dust. Health authorities in the UK are now advising people to go out without sun screens for ten minutes at midday in summer.

    Turns out that the ‘precautionary principle’, which said that even if there is the smallest risk that any exposure could cause skin cancer meant that there should be none, in fact raised the far greater risk of vitamin D deficiency.

    A classic really. You cannot avoid working out the best way through the risks, and the so called precautionary principle, when it comes to religion, climate or sun exposure, is a positive hindrance to doing that.”

    From comments at

    http://wattsupwiththat.com/2010/12/17/friday-funny-3/#more-29562

    10

  • #
    Senter

    A “must read” for today. Exploding the myth that Climategate was a hack.

    http://thepointman.wordpress.com/2010/12/17/why-climategate-was-not-a-computer-hack/

    10

  • #
    Ian Mott

    My comment on this thread at Jenblog. “Sorry folks, I’m with Polyaulax here. If the RAR is only 2% of the (total flow) volume then its impact on flood height is substantially less than 2% of the 9 metre flood height (at Wagga Wagga). The last 2% is spread over a much wider cross section than the first 2%. So even if the entire channel had vertical sides the RAR would only account for 18cm of flood height. But we know that the flood width will widen substantially as the water level rises. And it will do so in proportion to the slope of the flood plain towards the channel, which in the MIA is sweet FA. If the actual flood surface width was ten times the river width then this RAR would have only lifted flood level by 1.8 cm!!!

    Frankly, this whole thread is totally underwhelming. For fox ache, this was the last week before the deadline for submissions on what will happen to 3000GL EACH YEAR of real people’s precious water and this blog was wandering off up a barely relevant blind alley over what some bureaucrats might have done with 7GL/day during two weeks of a one in 50 year flood event. Yes, it might have pressed a few buttons but in the big picture it means absolutely jack $hit.

    10

  • #
    wendy

    “Ian Mott” (31), this “Polyaulax” character is a well known TROLL who frequents Andrew Bolt’s and various other blogs.

    “Polyaulax”, is known to be a bone head and Pillock.

    Anybody who agrees with that numskull is therefore tarred with the same brush………….

    10

  • #
    wendy

    “Another Ian” (29),

    Beware the Precautionary Principle (which is NOT a scientific principle)……….

    http://www.sirc.org/articles/beware.html

    10

  • #
    Ian Mott

    Wendy, did you actually read what I said? Or do you have a brain that slams shut when anything inconvenient comes into view? I’ll take a grain of truth from anywhere, even from known trolls, so either give me some clear data that would indicate that this snowy release is anything but a beat up or take your ignorant tushy and jump.

    We know the 6912ML/day from the snowy was split between the Murrumbidgee and the Murray, so it is only 3,456 ML into each river. And no-one has provided numbers for the total flow that would lead to any other conclusion that snowy water was only 2% of total flows. And that is unlikely to have added more than 2cm to the flood height. It is 3/5ths of 1/8th of sweet FA.

    10

  • #
    wendy

    Just as I suspected this “Ian Mott” is yet ANOTHER Arrorgant and Ignorant TROLL who has escaped from the LEFTIST LOVIN Centre, otherwise known as the ABC (Australians Being Censored).

    Please share with the class “Ian Mott”, how is that global warming thing working out for you????????

    What a shame that your property was not one of those flooded!

    Ignoramus!

    10

  • #
    Ian Mott

    Wendy, I have had some impressively self opinionated feedback in my time but this would be the first time ANYONE has ever called me an escaped troll from a leftist love-in. Can I forward your carefully researched opinion to the hundreds of bureaucrats that have had a dose of my “leftist love-ins” so they might understand the nature and extent of their missperceptions?

    Get a grip, you silly poop, and at least do a google search before you stuff your foot even further into your ample gob.

    And as for that “global warming thing”, I was co-founder of the Climate Sceptics Party, and you might care to take your sorry ass over to Jennifers own blog and read my articles there, especially the one sticking it up the ABC on “rising sea levels or sinking islands”.

    You are really fortunate to be only using your first name here, Wendy, because you have made a prize fool of yourself.

    10

  • #
    Tel

    If the RAR is only 2% of the (total flow) volume then its impact on flood height is substantially less than 2% of the 9 metre flood height (at Wagga Wagga). The last 2% is spread over a much wider cross section than the first 2%. So even if the entire channel had vertical sides the RAR would only account for 18cm of flood height. But we know that the flood width will widen substantially as the water level rises. And it will do so in proportion to the slope of the flood plain towards the channel, which in the MIA is sweet FA.

    This is completely wrong, try figuring out the units at every step and you will notice that a flow is measured as volume/time but the water on the ground is measured as volume. Thus, direct comparison of flow to volume is meaningless. Of course, the missing factor is time, and although the peak flow rate of the rain is high, the time spent raining is relatively brief. The “environmental flow” from the lake is continuous and so total volume over sufficient time is very large.

    For any given flood plain, available storage is part of the picture, but maximum rate of drainage is the other part. So when the inflow is greater than the maximum drainage, it consumes storage until it floods. The “environmental flow” pushes new water in as the existing water drains away, thus both increasing the height and prolonging the duration of the flood.

    As an example, consider that a factory worker on an assembly line takes an absolute minimum of 100 seconds to process one widget. You feed the line at a rate of one widget every 101 seconds and the factory worker takes a 1 second break between operations (just enough to take a deep breath). Feed the line at one widget every 99 seconds and what happens? The difference is only 2%.

    10

  • #
    wendy

    [snip… c’mon Wendy. — JN]

    10

  • #
    Ian Mott

    For pity sake, Wendy, go and get some decent roughage in your diet. Your posts read like you haven’t had a bowel movement for three weeks!! And if you can’t get laid, get a vibrator.

    Tel, I have seen some pathetic attempts by suburbanites at making sense of natural systems but likening a river to an assembly line would have to take the gong. When rivers exceed their capacity they just overflow, they don’t spin out, go haywire, or undergo any other sort of calamity. Get a Grip.

    I have a brother and a brother-in-law who have both lived and worked with the Murray river. I am advised that it takes more than 100,000 ML/day to break the banks at Wagga. And once it does the land slopes AWAY (down) from the bank and the water spreads over a very wide area. The width varies but over large parts of the Lachlan the flood waters are up to 70km wide.

    A hypothetical discharge of 80m/s, split between two rivers equals 40m/s in each would, if flowing at a speed of one metre/sec, and spread over a width of 70km, would lift the flood height by 0.57 of 1 millimetre. Halve the speed and it will lift the flood height by another 0.57 of 1 millimetre and halve the width as well and the total additional rise from the 40m/sec will only be 2.14 millimetres.

    So the parts of my analysis that assumed a spread of only 1.6km was way short of the mark. And that means my estimate of the insignificance of these SH releases was seriously understated.

    10

  • #

    Ian, thanks for bringing in numbers. I was wondering myself just how significant the flows were which is why I tried to translate that to the (not terribly useful) number of Olympic Pools it would fill.

    It doesn’t change the fact that it would have been useful and easy to include a clause where the floodgates were closed without penalty in the event of a flood. This still makes a good case study in bureaucratic ineptitude.

    this was the last week before the deadline for submissions on what will happen to 3000GL EACH YEAR of real people’s precious water and this blog was wandering off up a barely relevant blind alley over what some bureaucrats might have done with 7GL/day during two weeks of a one in 50 year flood event.

    Over here in isolated, mostly bone dry WA I haven’t tried to get into the details of national water policy. You’re most welcome to point us the big issues.

    Wendy — please stop attacking people who come armed with numbers and details.

    10

  • #
    Tel

    Ian, please read this to help see the problem with your approach:

    http://en.wikipedia.org/wiki/Dimensional_analysis

    You might have extraordinary levels of practical experience, but if your units don’t fit together then you are talking gibberish. Don’t take my word for it, ask as many people as you like.

    The assembly line example is illustrative of the importance of considering both rate of inflow and rate of outflow in a system. It’s a generic issue, maybe you feel uncomfortable that water and widgets obey the same basic rules, but they do never the less. If you were more on the ball you would point out that an assembly line has minimal storage capacity, while a river system has substantially more storage capacity, but of course then I would point out that the difference is only how quickly the system breaks down because all systems exhaust their storage capacity sooner or later (and yes, the concept of time creeps back into it — flow = material / time). Your analysis ignores the concept of time completely so it would be a wrong method for both the river, and the assembly line.

    I have a brother and a brother-in-law who have both lived and worked with the Murray river. I am advised that it takes more than 100,000 ML/day to break the banks at Wagga.

    I presume this means that the maximum working drainage rate (i.e. without spillage) of the river system is a bit less than 100,000 ML/day well I did a search for comparable figure on the environmental flows, Jenifer claims “80 cubic metres per second” which translates to about 7000 ML/day or about 7% of the total drainage capability.

    The document at …

    http://www.conservationsa.org.au/component/content/article/454-environmental-flows-for-the-river-murray.html

    … mentions a figure of 1500 GL/annum which translates to approx 4000 ML/day but then it also reserves the right to demand 3000 GL/annum (or 8000 ML/day) if they feel like it, so that’s at least on a magnitude ballpark with Jenifer’s figure. I’ll go with 7000 for argument’s sake.

    So we know that the operational drainage at Wagga Wagga is 100 GL/day but the inflow from rain is haphazard (with brief peaks). It happens I was watching the rain radar (as I regularly do for my job) and saw the two big waves pass over from Adelaide through to the East coast. First wave hit Wagga Wagga on 2010-10-03 but no flooding… why no flood? The influx was brief (less than a day) and local storage deals with it. The second wave came over 2010-10-09 which was only 6 days later, but it was also only a brief deluge lasting less than a day. Thing is that the environmental flow was going continuously for those 6 days, which represents ( time * flow ) = ( 7000 ML/day * 6 days ) = 42 GL of volume that would have drained out of storage between the two waves of storm that came through.

    http://www.bom.gov.au/climate/dwo/IDCJDW2139.latest.shtml

    That’s the rainfall in Wagga Wagga (and of course you could go to all nearby stations but trust me the rain rolled through from West to East over a duration of a bit more than a day).

    I’ll admit that I don’t have the details of how much local storage is available under what conditions, but I’ll guarantee that your calculation doesn’t work it out either. You need to know the input upstream flow as well (the one coming from Qld) because if that’s a significant proportion of your available drainage then it takes even longer to recover from a one-day weather event.

    Now here’s an example of how not to do the calculation:

    A hypothetical discharge of 80m/s, split between two rivers equals 40m/s in each would, if flowing at a speed of one metre/sec, and spread over a width of 70km, would lift the flood height by 0.57 of 1 millimetre.

    Trying to solve it by switching everything to linear velocity, is only valid for a steady state. Does the 70km wide flood plain operate in steady state as a continuous channel? Absolutely no it does not, there is always a pinch point somewhere downstream. I confess I don’t know exactly where that point is, but the drainage through the pinch controls the outflow with or without overflow at the banks, everything else is merely more local storage, which buys time. You can never solve it while you remove the concept of time from the picture. The environmental flows are continuous, the rainfall is sporadic.

    Seriously though, go and chase up the Dimensional Analysis, it helps you sort out a lot of concepts, and you can check your work, and provide a calculation that other people can follow.

    10

  • #
    Ian Mott

    Tel, you have managed to supply all the form of a coherent argument but with none of the substance. You have even managed to imply that the flood levels at Wagga are influenced by flows from Queensland. Get a bloody map before you open your mouth.

    And keep up with the brief. The 80m3/sec is split between the Murray and the Murrumbidgee, making 40m3/sec for each system or only 3500 ML/day. And you overstate the importance of the time variable. It is highly relevant over a longer period but in 2-3 weeks of close to constant high volume flood flows it is not relevant at all. Think about it, constant releases into a close to constant high volume flood flow provides minimal scope for anything but a quite predictable outcome.

    And for your information the 70km wide flow in the Lachlan does not have any “pinch point” as you call it. It just flows out into broad ephemeral lakes where it evaporates.

    10

  • #
    Ian Mott

    In fact, Tel, your methodology is fine for calculating the total volume of flow but that is not what we are trying to solve. We want to know the impact of the 40m3/sec on whatever flood volume was flowing at any time during the flood period. The snowy releases were constant, and as each tributory joined, the snowy release portion moved at the same rate as the waters it joined. And this allows us to derive an approximation of the impact of that additional volume on the upper layer of the water column.

    But I note that after dazzling us all with your methodology you then failed to provide us with the results of your calculations. Instead, you took the 100,000 ML figure that I supplied as merely the point when the river broke its banks at Wagga and used it as the denominator for a very rudimentary calculation. The fact is that the volume at Wagga was very much in excess of 100,000 ML for the simple fact that the banks had very much overflowed.

    This is the fundamental fallacy in your assembly line analogy. Flooding rivers do not choke from excess flow volume, they simply overflow to create a conduit of substantially greater capacity which continues to flow until, having flowed, moves on. And moving on would be a good thing for all of us right now.

    10

  • #
    Tel

    OK, so the Qld water joins downstream of Wagga, it still affects the result because higher river levels downstream will reduce the available drainage flow upstream. At any rate, the point I’m trying to make is that the system is not in steady state.

    The big rains hit on the 3rd and again on the 9th of Dec, and the river height was rising after that to a peak on the 12th. So that’s a bit more than a week of rising river which means more water is coming in than can drain away. So for starter’s the environmental flow meant that the river level was higher to begin with and thus had less room to rise, and as well as that, it rises faster because the system as a whole needs to cope with more input flow, for a constrained output flow.

    Let’s suppose the environmental flow was turned off as soon as the first big rain came down on the 3rd (which would have been the smart thing). That’s 9 days of flow that was not able to clear out of the system (when the river is rising, any additional water is not draining out, it just makes it rise faster). 7000 ML/day * 9 days = 63 GL of water that added to the peak volume of the river.

    After it hit peak and the water started going down again, the environmental flow results in longer time for the floodwaters to go down again. That means more economic loss for the people who are driven out by the floodwaters.

    Depending on evaporation to clear this will only get rid of approx 5 millimeters per day, so in order to evaporate away 7000 ML/day you need to would need to flood 1400 square kilometers of land (or 140000 hectares if you prefer).

    This is the fundamental fallacy in your assembly line analogy. Flooding rivers do not choke from excess flow volume, they simply overflow to create a conduit of substantially greater capacity which continues to flow until, having flowed, moves on. And moving on would be a good thing for all of us right now.

    When an assembly line goes wrong, the loss is to the factory owner. When the river floods people’s houses, the loss is to the nearby home owner. Of course the river is going to keep working as a river, from an environmentalist’s point of view that’s all that matters right? There’s land, there’s a river, the river is wet, tick the box, environment is all good.

    However, as humans we manage our environment, which means people who live next to that river call it home, and they benefit from the river not flooding, and if it does flood then best to minimise the area affected and the time it stays affected. That’s why dam building is a good thing for humans, that’s why sensible regulating of water flow is a good thing.

    How can I move on when so many government dingbats are making sure that we humans cannot operate in our logical capacity as humans? In most of the capital cities they are have built expensive desalination plants while making regulations to strongly limit the size of water tanks that ordinary householders can use (and now they are bringing in rules to make people pay for the rain runoff in their own gutters). While those desalination plants consume electricity they bang away at householders telling them not to run their air conditioners.

    Farmers can’t even build dams on their own properties because special environmental fairy dust says that it would hurt the river. Then when there is a flood, and people lose their livelihood the environmental fairy dust blames it on four wheel drives. When someone gets cranky about environmental flows feeding into the middle of a flood zone, we just get excuses and inaction. If it makes so little difference, then why not shut the flow off, just to be seen to be doing the right thing?

    If I try to point out that many local dams on farms all over an area increases storage capacity and therefore mitigates flooding when a sudden burst of rainfall comes through — you just ignore the entire concept of storage and calculate everything in steady state.

    How about the people who want to regulate the life out of everyone else take a turn to just move on?

    10

  • #
    Ian Mott

    “That’s 9 days of flow that was not able to clear out of the system (when the river is rising, any additional water is not draining out, it just makes it rise faster). 7000 ML/day * 9 days = 63 GL of water that added to the peak volume of the river.”

    So now you are adding the whole 9 days worth to the flood peak? Isn’t that in direct contradiction of your previous sermons on the importance of time? And you are STILL using the 7000ML/day figure not the split 3450ML/day in each river.

    Nine days worth of flow at one metre per second will be spread over 778km of river length. Divide the real 31,000 ML by that and we get 40 ML/km of river length or 40m3/metre of river length. Spread that over, say, an average 20km wide flood width and we get 2 millimetres added to the flood height.

    Clearly, Tel, you are inclined to selectively retain even the most basic essential facts and apply them in a logical manner. I have no quibble with the rest of your post but, please, what you are flogging is no longer even a dead horse.

    10

  • #
    Debbie

    Does it really matter how much the SHL releases precisely added to the floods? Why are some of you arguing about how much? Isn’t the real issue why they put any water on top of a major flood at all? Have we forgotten why the dams were built in the first place? Do you realise that in the highest inflow year this decade, they have been emptying Lake Eucumbene, which is the “mother lode” at the top of the system? They have been doing this under the guise of environmental releases. For heaven’s sake! Which part of the environment needs some extra water releases from Eucumbene? Shouldn’t we be trying to conserve as much of the excess water as possible? They have been releasing an average of 4,500ML per day since July. The amount of “wastage” and the future consequences of this action is staggering. It is particularly annoying that the very people who yabber on and on about “water savings” and also blame regional communities for “wasting water” are the same people who have dumped a huge amount of water onto a flooded system that doesn’t need it.
    NSW Office of Water and Snowy Hydro Ltd have been aware of the anomoly in this licence for at least 12 months. Several water bodies and representative groups have pointed out the anomoly over many months. They have been writing letters and emails to each other for at least 8 months and were not able to fix the problem. Why not?
    Emptying water out of the major storage dam in the middle of the best inflow year in ages and also in the middle of a major flood is just plain stupid and potentially dangerous. To offer the reason or excuse that it’s because of the operating licence is unacceptable.Their other excuse is that most of the rain fell below the catchment area. Are they kidding? The inflow graphs and rainfall records tell a much different story. These “public servants” have been wasting a precious resource and they’re being paid to do it. I fail to see any common sense or practical water management here.
    Congratulations to Jennifer and everyone else who brought this issue out into the open. And Jo you have asked an excellent question: Isn’t this the kind of research that paid journalists should be doing? Let’s hope they spot this issue when they return from their Christmas break.

    10

  • #
    Ian Mott

    I understand where you are coming from, Debbie, but I make no apologies for correcting a gross and misleading exageration, even if it might appear to help our cause. I also make no apologies for persisting with the facts when those facts are met with responses like “bone head and pillock” by association, and “arrogant troll from a left wing lovein at the ABC”. You forget that the original story was a lurid exageration with only a tenuous link to the facts. And I have not spent the past 15 years fighting the same sort of crap from the greens to now stoop to the same level for nothing more than a convenient headline.

    We can be in the facts business or the bull$hit business. We can’t be in both. And lets not forget that we are talking about an action of minor impact, that took place over 3 weeks during a one in 50 year flood event. And for what? For two weeks of media noise when no-one is actually taking any notice, and even those who have will have forgotten two weeks later? And for nothing more than to reinforce the self evident truth that bureaucrats waste resources and retard potential?

    I was quite content to simply point out the relevant facts and leave it at that. But the record makes it clear that those facts offended certain people who then demanded far more of my time than they ever deserved. But isn’t it ever thus?

    10

  • #
    Debbie

    Thanks Ian,
    I agree with you. It’s not a good idea to jump in the gutter with the people we are attempting to expose.
    My major complaint is the unforgivable wastage.
    I know how this is going to affect water allocations and dam storages next year. There are certain sectors of the farming community and also ironically the environment which will pay dearly for this water dumping and mismanagement of excess water.
    Unfortunately the water wastage has been going on for way longer than 3 weeks. The actual amount will total over 800GL. It became remarkably insane over the 3 week period in question. There was no way they could justify what they were doing with any of their reasons during that period.
    A good question to ask is: Why are we emptying Lake Eucumbene at the top of the system when there are tens of thousands of megalitres belting over the barrages at the bottom of the system?
    Another question: Why are we emptying Lake Eucumbene into 2 dams (Blowering and Hume) which have been at over 100% for a long time?
    Another Question: Where do these people think the water goes once it spills over Blowering and Hume?
    Another question: When was it ever a good idea to empty a major storage supply onto a minor or a major flood?

    It is particularly annoying because it is the same people who will crow loudly about storage and wastage when they calculate next year’s allocations.

    I also want to congratulate you again on your excellent submission to the MDBA. I wasn’t kidding when I asked if you would apply for the Mike Taylor position. The “wake up to your stupid selves” approach is sorely needed.

    10

  • #
    Tel

    So now you are adding the whole 9 days worth to the flood peak? Isn’t that in direct contradiction of your previous sermons on the importance of time?

    I use 9 days worth because it is a reasonable estimate of the time between when it would have been possible to see that a flood was likely and when the actual flood peak arrived. This does indeed account for the importance of time: if the flow had been switched off when the first big rain hit, and switched back on after the river level started falling again, then a total of 63 GL of water would not have been released.

    It’s a pretty simple idea, when river levels are rising then water is entering the system faster than it is leaving, and the excess is going into storage. Integrating flow over time gives the total volume that must find some place to be stored.

    You presume that it would split half/half down the two rivers, I’m happy to go with that if you have a reference, otherwise it’s just a presumption, and a favourable presumption at that, why shouldn’t I make an unfavourable presumption to consider the worst case?

    You make a further presumption that a flood of approx 20 km wide will spread out all the way along the 778km of river to give a total of 15560 square kilometers of flood area, for the water to wash into. That’s an awful lot of flooded land, but it’s also rather unrealistic. No river in the world breaks its banks evenly along the entire length of the river — the excess water pools in particular places and breaks the banks in some places not others. Thus the volume of storage is nowhere near evenly distributed.

    What really should be calculated is how many extra houses were flooded because of that additional environmental water, and more than that, of those houses that were flooded, how much longer did they stay flooded than they needed to?

    Going with your half-strength flow, we end up with the need to store 31 GL (i.e. 31 million cubic meters) which could cover 31 square kilometers of land to a depth of 1m (let’s suppose 1m of floodwater is enough to force someone to leave their home). Maybe at an average of 10 houses per square kilometer that’s 300 families (and making a worst-case presumption about the half/half split makes it twice as big). Naturally, the real inconvenience depends on exactly where those houses are in comparison to exactly where the overflow spills into.

    If you can find a news report to say how large the actual area of flooded land was in this particular case, then divide that 31 million cubic meters by the actual flooded area to get the height difference if you like. Don’t give me this silly 2 millimeters business, the entire local government area of Wagga is only 5000 square kilometers which would be 6 millimeters deep if the extra water covered it all evenly, but we all know perfectly well that it was not evenly spread at all.

    Clearly, Tel, you are inclined to selectively retain even the most basic essential facts and apply them in a logical manner. I have no quibble with the rest of your post but, please, what you are flogging is no longer even a dead horse.

    I’m just asking you to give me a calculation that doesn’t make outrageous presumptions like believing in a 20km wide channel, evenly distributed the entire length of a river. I still believe you don’t understand the basic interaction between volume, flow and time or you would not be asking about the significant effect of the number of days the environmental flow runs for before peak flood height.

    I was quite content to simply point out the relevant facts and leave it at that. But the record makes it clear that those facts offended certain people who then demanded far more of my time than they ever deserved. But isn’t it ever thus?

    I didn’t demand anything, I just pointed out that your calculations used a badly flawed methodology, which you continue to insist is right. The answer you are getting is not even ballpark plausible.

    I’m not saying my answer is spot on either, but at least I understand the basic concept that if you tip water into a leaky bucket faster than it can leak out then the level in the bucket will rise, and the longer you keep that up, the more additional volume will need to go somewhere (until the overflow happens after some time has passed). If you want to stick with your methodology then there’s nothing I can do to stop you, by all means wait for the next person to come along and point it out.

    10

  • #
    Mark D.

    Ian, please don’t think you have wasted your time explaining these things. I’m 1/2 a world away from these floods and this argument has helped me to understand more of the situation. You rightfully should be “on edge” from the misdirected comments by some (no name mentioned) but I don’t think Tel should be lumped into that pile either.

    Debbie @ 48 has asked simple questions about (apparent) policy that seems illogical to me. Tel has given some weight to why the logic might be missing. I appreciate both (yours and Tels) efforts to arrive at better understanding (even if only mine).

    I feel like the whole world is (or will be) suffering from illogical policies foist upon us by “greenies”. Every story even if mostly ignored, is a learning tool.

    10

  • #
    Debbie

    I think as far as noticing the total absence of common sense and logic goes, we’re all on the same page here.
    Mark @ 50 is right: These are definitely “illogical policies foisted upon us by ‘greenies'” !
    I also think that Ian and Tel are both correct about the nature of floods and how much SHL actually contributed. They just viewed the figures from a slightly different perspective.
    We would be lunatics to suggest that these releases were a major contributing factor. It was definitely “Mother Nature” who was the main player here. They (SHL) would however have contributed something. Chokes in the system and the irregularity of river depth and also those jammed up dams, particularly Blowering, would all have made a contribution to the floods.I understand the basics of our rivers and how they flow and where they choke and where they spread. I would not presume to be able to calculate any exact figures as there are too many variables. You 2 obviously have the talent to do that.
    As Joanne said earlier, what is missing is some sensible legislation.
    This is a good case study in bureaucratic ineptitude.
    We also need to remember that the whole presumption behind the MDBP is that they believe they have the abiltity and knowledge to “manage” environmental assets and that the “Government” needs to have control of more water and more water management. All I’ve seen them do lately is manage to waste water, one of our most precious resources. Why on earth would anyone think we will be safer if we give them more control?
    They have broken the most essential rule in water management on a regulated system. Those dams were built to store water in times of excess so that we could manage the resource in the inevitable times of shortage.
    What have they done?
    Wasted water in times of excess and also dumped it onto a minor flood and then a major flood!
    They also believe they have somehow helped the environment by doing this.
    Ian’s point about the tiny effect that theses releases made to the overall flood is a valid one when viewed from this perspective.
    Tel’s point that they did nothing to help the communities affected by the floods is also a valid point.
    Our water authorities have done nothing to help the environment. It was always “Mother Nature” who was going to flush the system.
    Our water authorities did nothing to help flooded communities because they did contribute “something” to the flood.
    Their actions did nothing but waste water. Our river system and our inland communities will pay dearly for this ineptitude in the next few years.

    10

  • #
    Ian Mott

    No, Tel, you are talking through your backside again. You plucked 9 days release but then made no attempt to reconcile it with any form of flow or any width of flow, or any speed of flow, and then had the gall to suggest that I was lacking understanding of the importance of time. You then plucked a convenient area out of your bum (31 km2) of flood area that gave you a neat 1 metre of flood height. And throughout this whole sorry show you have not lifted a finger to google up a single jot of hard data.

    For the f#$%& record, you boorish pillock, go to google earth, type in Wagga Wagga, NSW, Australia. The river you see there is the Murrumbidgee. Place your cursor over the river and observe the river height in feet as shown at the bottom of the image. Click on the ruler symbol in the top menu and you can then move your cursor up or down until you find the same height reading. Click at that point and then move the cursor back over the river to the next point where it shows the same height and click again. This will show you the distance between the two points which will also be the width of the flood water when the banks have overflowed.

    The rest of the readers can note that for nine such transects, done over 30km of river, (15km above and below Wagga Wagga) revealed an average width of 4.4km with a range from 1.8km to 8.5km. This 30km length of river would account for 8 hours of SH discharge if the mean rate of flow was 1 metre/second (ie 3.6km/hour or walking speed).

    The 40m/sec split discharge rate provided by Polyaulax, and not contested by Jen Marohasy, when spread over the 4400 metre mean flood width, would account for only 9mm of additional flood height at Wagga Wagga.

    For Tel to fit his stupid nine days of SH discharge into 31km2 of flood area to produce his even stupider 1 metre of flood height, it would fit into just 7.05km of river length. And that means the water would need 9 days to flow 7km, or 777 metres/day, 32m/hour, 54cm/minute, or 9mm/second. That is, it would be barely moving at all and it would take about 7 years to get to Lake Alexandrina, for fox ache.

    At a flow rate of 1 metre/second, or 82km/day, it will take flood waters 24 days to travel 2000km. So tell us all, Tel, which of us is working in the realm of reality and which of us is totally off the planet?

    For the record, transects taken further down river revealed a likely flood width at overbank of 17.8km at 10km East of Narrandera, 16.6km at 8km West of Narrandera, 22km at Leeton and 45km at Griffith. So the SH discharge is likely to have added 1.8mm to the flood height at Leeton and 0.88 of 1mm at Griffith.

    10

  • #
    Tel

    I’ve poked around a bit more and I will congratulate the Murray Darling Basin Authority for making the effort to release data openly. You can get live river data and graphs of a month of historic data on their website here:

    http://www.mdba.gov.au/water/live-river-data

    Although Wagga Wagga is on their map, when I click on it then I get taken to the Murray River, but I could find Balrandald which shows a peak Murrumbidgee River flow of 149000 megalitres per day on 12th December, and it has only dropped about 10% since that peak. This suggests that any new storms in the area will almost certainly flood Wagga again.

    No information further upstream though ?!?

    Also, for what it’s worth Wagga Council paid for a fully working dynamic model of the river which is documented in their 2004 Flood Survey but the model itself does not seem to be available to the public. Supposedly it has been closely calibrated against the 1974 and 1975 floods do at least in theory this model could be used to give an accurate estimate of the outcome of various operational scenarios (much better than a hand-waving back of the envelope calculation).

    There’s also an overall “Water in Storage” picture estimating the basin at 82% full (but only gets updated every few weeks, and no historic values).

    http://www.mdba.gov.au/water/waterinstorage

    The MDBA claim to operate the river as follows:

    Each day, MDBA staff ‘operate’ the river system by directing releases from storages and controlling diversions of water from the river for irrigation and agricultural use, and for consumer in urban areas. They then advise staff of the state authorities working at the various structures of the rates of release for that day. During floods, flows may be adjusted every few hours.

    Operational decisions take in a range of technical considerations such as flow requirements, salt and water level changes, estimated evaporation, forecast rainfall and the water-carrying capacity of the river at various locations.

    This might be some wishful thinking, I don’t find any list of operational directives, and I seem to remember Tony Windsor saying the the MDBA don’t actually have operational authority over the Snowy Monutains (or anything else much).

    10

  • #
    Tel

    Ian, sorry to have you swearing but you are still wrong, and I can tell you are wrong because you approach is broken even in principle. What’s more now that I’ve searched further, the Wagga 2004 Flood Survey already considered your approach to the calculation and rejected it:

    A steady state model uses a constant flow value. For a study area such as the Murrumbidgee River at Wagga Wagga, an unsteady state model is necessary to enable adequate simulation of the flood hydrograph with its variance of flow over time. A one dimensional model allows flow along only single paths or reaches. A quasi two-dimensional model uses one dimensional flow paths but allows for interconnecting branches and overflow branches or weirs. It is therefore able to represent interactions (flow transfers) between the main river and the overbank flow path areas. A fully two-dimensional model allows water to flow in any direction and does not need to use any pre-defined channels or flow paths.

    Huge amounts of measuring around on Google Earth aren’t going to fix a broken methodology, and all I was trying to point out is that your original calculation makes steady state presumptions that ignore the concept of available storage space being filled in a dynamic manner over a period of time.

    If you want to check the MDBA historic graph of Balranald you can see it here:

    http://riverdata.mdba.gov.au/sitereports/410130/mdba_410130_site_report.html

    Note that the river level was continuously rising for at least 16 days so if anything my 9 days was an underestimate, but I only recently found that data source. At any rate, the system is not remotely close to being in steady state, so you can take all of your steady state calculations and throw them out the window.

    As for propagation time down the river, no I’m not trying to take that into account because the propagation rate of the change is not the same as the average downstream velocity of the water, nor is it in any fluid (when you stamp on the brakes in the car, the fluid only moves a few cm under your pedal but the brake comes on instantly even at the end of a few meters of hydraulic pipe). Anyhow your steady state model also ignores propagation time so I don’t see why you are making such a big deal out of it. There’s no reason why the Snowy Mountains operators could not have seen the river levels starting their steady rise from right back as far as late November and it doesn’t require Einstein to figure out that if you tip extra water into a system where river levels are rising, then they will rise faster — why is this difficult?

    Finally the Flood Survey on the last page shows a map covering what has been surveyed to be the “at risk” area in Wagga which is around 15 kilometers long and 5 kilometers wide, let’s say 75 square kilometers. OK, that’s twice as big as my first estimate but obviously it isn’t going to fill up exactly evenly anyhow, as I point out above Wagga Council are sitting on all the tools to do a very accurate model anyhow, there’s no value in my trying to poke around with Google Earth, because they surveying has already been done.

    What I have successfully pointed out is that trying to wave this away with answers in the millimeter ballpark is completely incorrect. I think I’ve pointed this out with sufficient detail now, there’s no point in repeating myself any longer. I’ll not be bullied by your pushy pushy attitude, you either get it or you don’t. You are more than welcome to come up with any answer you see fit, I only hope that the Wagga Council takes the trouble to run a proper model and publish a real study of this incident (unlikely though that is). They should at least do that much on behalf of their voters.

    10

  • #
    Ian Mott

    Tel. The only person to use a steady state model on this thread was yourself with that stupid, totally arbitrary use of 31km2 to match 31 GL of release. You simply cannot get your mind around the fact that a 1 metre high surge in water flow could not possibly flow at the rate of just 32 metres an hour that would be required to get 9 days worth of discharge into such a small area of flood surface.

    You have provided a convenient quote but my use of multiple widths and my continual references to the implications of changes in flow rates over time, and with flow width, makes it clear to all but the seriously comprehension deficited that I was NOT applying a steady state model.

    And get a grip. Clearly the boundaries of the Wagga Wagga Council flood zone might have something to do with the boundaries of the shire instead of the boundaries of the flood.

    You should also keep in mind that evaporation at this time of year is in the order of 5mm per day. And that means the mere presence of cloud cover can reduce water levels by as much as five times the impact of the SH releases.

    I go back to my very first comment on your posts. You have mustereed all the form of a coherent argument but you consistently failed to deliver any of the substance. Indeed, on the few occasions when you have ventured beyond rhetoric you have been found to be seriously innumerate.

    10