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39 responses to “Amazing rain, and what the flood engineers did about it”

  1. Grey

    If the Wivenhoe dam engineers are shown to have mismanaged their management that opens up the possibility for insurance companies to sue the government (ie the taxpayers).

    This would allow the monied class to leverage the tax raising ability of governments to its own profit. An outcome that naturally the Australian would be very happy about.

  2. mediatracker

    Impressive report Brian obviously involving a tremendous amount of work. What a pity Hedley Thomas didn’t do as much.

  3. John D

    Good one Brian. Shame that most (all?) MSM failed to meet this standard. The message coming across from the MSM was that the manual was god, the engineers devious incompetents and that the CEO should have abandoned his holidays sooner than he did and take personal charge.
    My take on what you said is that the engineers did a good job on the basis of the information that they had at the time and their actions would have saved 300 houses from damage if the weather had been as expected when the decisions to delay increasing flows above 3500 were made. I must admit that experience as a commissioning engineer, operating manager and control room operator as well as working 12 hr plus shifts give me a feel for the sort of pressure the engineers would have been under. It also creates a wee bit of prejudice against lawyers and journo’s who have never been it the sort of situation.
    There are a number of dangers that arise from some of the things that have been said:
    Firstly, it would be very dangerous we have a legal situation that says the dam operators can only be sued if the manual is not followed. It is not practical to have a manual that covers all eventualities. This is why there were engineers on shift who had the technical competence to make decisions. It is crucial that that the engineers are able to make decisions without having to consider legal ramifications.
    Secondly, we are currently obsessed by the flood issue and seem to have forgotten how close Brisbane came to essentially running out of water a few years ago. If this had happened the economic damage would have made the flood costs look like petty cash. As you say,

    it seems to me insane to wind down the dam in September if an El Nino is predicted. It is also insane to be letting water out at the end of March, as happened last week, to bring the dam below 75% at the end of the wet season when the La Nina has broken up.

    This decision needs to be publicly challenged.

  4. Roger Jones

    Excellent post, Brian. Your first section shows the problem with legally-focussed commission investigations. They aren’t framed properly to address risk and they don’t understand risk. The Victorian Bushfire Commission is another example.

    My view is that these commissions be based on how risk was managed, have the skills to forensically examine risk and risk management, then assess whether the regulations and actions of individuals were adequate. Only then should responsibility be allocated. Responsibility should be assessed at personal, institutional and governance levels. The trouble with rules in these situations is they often don’t work in emergencies (for many reasons). So assessing actions against regulations is a key task.

    Then, it can be tested in court. Blame and allocation of penalty and recompense get dealt with by courts.

  5. David Allen

    The outcome of this event will be a further retreat from expertise and knowledge as in other professions. Prepare for your next flood to be managed by politics, vox pop & prayer. Perhaps talk back callers to radio stations could directly control the sluice gates. And a “War on weather” could be declared!

  6. Helen

    This will exacerbate the decline in numbers of engineers graduating in Australia. I’m not expert enough myself to know just how serious were the mistakes made but it’s obvious that you can work round the clock in shocking conditions, do your very best and then be demonised as criminals. I can’t imagine the health, family and career impacts on these men. Who’d do it? Years down the line the government will be all, “woe is us, there aren’t any engineers.” Oh that’s right, we’ll just poach them from other countries. As you were.

  7. billie

    Thanks for this post. I feel for the engineers named for contentiously doing the best they could which unfortunately flooded Brisbane. It’s not as if Brisbane wasn’t going to flood under that rainfall.

  8. Moz

    [email protected]: I’m not sure kids will be looking at things quite the same way. Your point might feed into it, but I get the feeling they’re more picking up on the “what a bunch of useless dicks those engineers are” vibe. And the “lawyers are much better at knowing what to do than engineers are”. Same result, but less nuanced. And I suspect you know my opinion of nuance and the media.

    It also directly feeds into insurance costs for engineers. Which doesn’t affect anyone directly, but it makes engineers more expensive to hire. So increasing the pressure to have fewer engineers working fewer hours. Otherwise how will we pay for the lawyers to defend them?

  9. Moz

    Brian: the people who exactly follow the manual are called technicians, and they’re a lot cheaper than engineers.

    Of course, when situations outside the manual arise the technicians will look for guidance. It’s quite clear from the media coverage that they should look first to the media, then to the insurance company lawyers for that guidance.

    There are few things more annoying to an engineer than being on site, looking at a problem, and not being allowed to fix it because someone irresponsible has made a rule. Irresponsible in both senses: not responsible for the outcome of their decision; and uncaring about the consequences.

    One key difference between engineers and lawyers is that lawyers are not liable for the consequences of their advice, but engineers make actual decisions and have to suck up the results.

  10. wilful

    Exactly the same stuff happens with fires. This issue will continue to come up, more and more, as the target area for fuel reduction burning increases. There will be less and less suitable weather, there will be less and less experienced fire incident controllers, there will be more pressure on them, and they will say sod this for a dumb job. If they’re held totally accountable for dumb politically motivated policies, and are operating in a risk management world where mistakes have to be accepted as occurring, and are then excoriated for the inevitable failures, of course things will go wrong.

  11. desipis

    Brian, thanks for this post. As an engineer currently studying to become a lawyer it’s interesting to see the view from someone who is neither. Reading the relevant sections in the report did little to ease my concern about the engineers being the subject of a witch hunt. I found the way the commission interpreted the manual, and the obligations it put on the engineers, to be overly legalistic given the context. In particular section 16.3.5, where there seemed to be a complete lack of understanding on part of the commission about the distinction between an engineering strategy and an operational procedure.

  12. Anderson

    I presume the initial manual was written with risk assessments in mind.

    They may have regarded that frequent low level floods is an accepted cost to lower the risk of damage of a much bigger flood. Even if this may have meant that the dam behaved as a ‘flood amplification’ dam for a period.

    So if the engineers deviated from the operating manual, they better have very good justification as to why they believe the original manual was wrong (in terms of risk/reward)

    And the fact that they’ve successfully used the same less-aggressive strategies many times in the past to avoid low-level floodings is not an excuse either.

  13. Occam's Blunt Razor

    You didn’t discuss the role of the dam. I was under the impression that it was built with the original purpose of flood mitigation. It wasn’t built for Water storage but subsequently became used for that role (as other proposed dams were cancelled).

    If this is correct then shouldn’t the dam engineers have been letting more water out to try and lower the level to 100% earlier?

  14. Tim Macknay

    One key difference between engineers and lawyers is that lawyers are not liable for the consequences of their advice, but engineers make actual decisions and have to suck up the results.

    I presume by that you mean that lawyers are not liable for the consequences of a client’s failure to follow their advice (although even that is not entirely true, since lawyers can be, and have been, held liable for not expressing their advice clearly enough, or not putting enough emphasis on a particular risk even if they did mention it).

    I’m not convinced there’s much to be gained by simplistic “engineers v lawyers” finger pointing. As a lawyer, my personal view is that the law of negligence suffers from a ’20/20 hindsight’ problem that too frequently creates unrealistic demands on people making decisions in situations of uncertainty (such as engineers, for example). This is partly the cause of the excessive litigation paranoia that infects every endeavour these days. Another partial cause, ironically, is the quite onerous obligation of lawyers themselves to identify every possible eventuality and alert their clients.

  15. John D

    The interesting thing will be what happens next time around. The operating engineering team was put together from a number of sources when levels in the dam were starting to be of concern. Given the crap this team of engineers has had to cop one wonders how many engineers with the necessary specialist knowledge will be willing to do the job?
    Anecdotal comments suggest that many engineers are unwilling to become mine mangers these days because of the legal exposure and the possibility of going to jail. I think it was Bligh who said that the dam engineers would be paying their own legal fees if found guilty. Few engineers have the sort of money required to cover those sorts of costs.

  16. Hal9000

    Brian @6

    I’m not sure how the whole insurance thing sits, but there is no legal requirement for the engineers to follow the manual.

    My understanding Brian (from an impeccable legal source) is that the engineers and the State are indemnified against litigation if and only if the manual is followed. Therein lies the problem.

  17. wbb

    Great reading. Thanks Brian.

    As one who works 18 hour oncall shifts under high pressure – but not where failures/accidents/misjudgements can destroy houses – I can only sympathise with the damn engineeers.

    I have many manuals at my disposal – but neither the time to consult them, nor the faith in their quality to follow them.

    Root cause analysis is just often a fancy term for scape-goating.

  18. Wantok

    Hal 9000 @ 20 :
    I would be checking that impeccable legal source because insurance (Professional Indemnity in this case) is all about human failings ” acts, errors and omissions”. If the manual was competent and the engineers failed to follow it and this was causal to the damage then the PI insurance comes into play to indemnify them .

  19. paul of albury

    Perhaps they can replace the engineers with lawyers if following the documentation is paramount. And they’d prioritise avoiding liability and any future enquiries by lawyers would understand their decision making better than they would engineers.

  20. paul of albury

    Brian, my comment was more sarcastic than serious. I’d hoped it was ridiculous enough for this to be clear.

  21. Bill

    They remained in W1 for 36 hours in clear breach of the manual. Had they followed the manual then the emergency releases made on Monday/Tuesday would have been much smaller, possibly zero. The unnecessary emergency releases undoubtedly contributed to the size of the Brisbane flood – how much would require detailed modelling.

    Then it seems they updated the operating logs nearly two weeks later, and were very economical with the truth.

    Open and shut case of negligence.

  22. John D

    Bill: If they had stuck to the manual and the weather had turned out as predicted 300 houses would have been flooded and 700 people displaced just to protect the engineers from the sort of claims you made @28. In this case we would probably have had an inquiry into unnecessary flooding with the engineers being scapegoated for not using their professional skills. If you look at the third graph in Brian’s article the clear message seems to be at first reading that it was sometime during the 9th at the earliest before there was any evidence that drastic action was required.

    It does seem, however, was that one of the things that was missing was an assessment of weather risk. Brian says:

    Both this document and the meeting notes mention the rain influence tending to miss the upper Brisbane segment and move south to the Lockyer and Bremer catchments according to the forecast…….
    the weather system did in fact settle over the Upper Brisbane and especially the Stanley catchment and Mt Glorious. An outflow level of 1400 cumecs decided at 3.30pm was passed at 6pm and increased steadily from there.

    The first peak inflow of 10,095 cumecs was reached at 8am on Monday 10.

    The cloudburst near Toowoomba which devastated Grantham occurred from about 2pm on Monday. The engineers didn’t know about it for about three hours as it fell between the gauges on the eastern escarpment of the range and didn’t show on radar.

    What appears to have been missing was a weather risk assessment that put a figure on the risk of the weather pattern and rainfall levels being critically different to the “most likely” prediction. This suggests that there needed to be weather experts working 24/7 with the engineers to flag the risk that reality would be much worse than the reality.

  23. John D

    During one stage of the flood the engineers were in a position where they had to decide whether to flood some houses (when this may not have been necessary) to reduce the risk of damage to other houses. This should never have been an engineering decision. It is what we elect politicians to do.

  24. desipis

    [email protected], there’s a key fault in your (and the commissions) reasoning.

    The strategies W1 to W4 only provide guidance as to the relative priorities of outcomes for dam operations. It’s only by applying modelling and professional judgement that one can arrive at a determination as to what action is appropriate. Prioritising an outcome, whether minimising damage to urban areas or protecting the dam wall itself, is a meaningless exercise if there is no actual risk. Where there is no risk to a primary outcome then it would be the other outcomes, presumably the primary outcome of the previous strategy that would effectively guide actions. This means that in many circumstances there would be no practical difference between one strategy or another.

    From my general engineering experience, engineering strategies such as the W1 to W4 covered by the operations manual are intended to be used to develop specific operational procedures with limited scope for technical staff or flexible frameworks (including configuring sensors, dynamic software models, processes, spreadsheets, etc) for engineers. The later need to remain subordinate to professional judgement as it’s not feasible to sufficiently consider all possible scenarios to develop more deterministic processes.

    Reading the dam operations manual, its obvious the strategies themselves are grossly insufficient to be considered something directly applied during operations, particularly crisis situations such as a major flood. While it might be considered an ideal for auditing purposes, nothing in the manual specifies the recording of the particular strategy selected. In fact the wording and structure of that section of the manual suggest its simply a recording of the current strategies used (potentially based on input from the operations engineers themselves), not a top down specification of the strategies that ought to be used. In such circumstances the strategies in the manual are likely to be gross simplifications of the complex issues of combining a large amount of data into qualitative assessment and forming a judgement about appropriate action. Attempting to consider the strategies as defined in the manual as authoritative in such circumstances would be irresponsible.

    The more important issue to record, from an engineering perspective, would be the point when circumstances cause the primary outcome of the relevant strategy to be under risk and begin to drive what actions are taken. It’s in this context that the report at 6pm on the 8th (~12 hours into your 36 hour window) and its reference to the “application of W2” should be read and understood (see section 16.7.2). It indicates to me that the engineers were already prioritising the primary outcome in W2 (if not W3) but at that stage had made the judgement that the outcomes were not at risk. By “application” I interpret it to mean changing actions (dam releases) to protect outcomes, to apply it in the real world, not changing the priority of outcomes in considering actions.

    This is another key point where I differ with the naive “plain reading” and legalistic approach of the commission. It’s also worth pointing out that judging from the report the commissions took a view that is contradicted by the views from 3 of the 4 experts giving evidence. Importantly a breach of the manual doesn’t necessarily mean they breached their duty in a negligence context; although the manual is potentially persuasive in determining what they had a duty to do.

    Had they followed the manual then the emergency releases made on Monday/Tuesday would have been much smaller, possibly zero.

    Further to whether they actually breach the manual, there is nothing in the manual that dictates how much water to actually release. While all strategies involve prioritising one particular outcome, it’s explicitly stated in the manual all other outcomes must continue to be contemplated. It’s quite possible that (even if they were operating under the ‘wrong strategy’) that operating under the correct strategy would not have resulted in material difference in dam releases given the information the engineers had at the time. Importantly for showing causation in a negligence case, this is a question the commission appeared to not even attempt to answer. The commission’s report doesn’t accuse the engineers of causing damage, it’s accuses them of something akin to an “engineering thought crime”.

  25. John D

    Very well put Desipis. This part really gets to the crux of what the manual was all about:

    Prioritising an outcome, whether minimising damage to urban areas or protecting the dam wall itself, is a meaningless exercise if there is no actual risk. Where there is no risk to a primary outcome then it would be the other outcomes, presumably the primary outcome of the previous strategy that would effectively guide actions. This means that in many circumstances there would be no practical difference between one strategy or another.

    In these terms an examination of the third graph above suggests that the dam was being operated within the manual guidelines given that even engineers cannot predict the future. My only comment is that the flows from the dam might have been raised closer to the max allowed by W1 priorities a bit sooner. However, keep in mind that even engineers cannot see into the future, the high inflows started on Sunday and, until the second surge of high inflows started on Tuesday it looked as though the dam would be brought back to normal levels without exceeding the W1 max flows.

  26. John D

    This is the third major disaster inquiry that touched on areas where I have had some relevant experience. In each case my conclusion was that the outcomes were flawed because the inquiries were run by lawyers who had no relevant experience.
    The first of these was the Esso Longford gas explosion Two people were killed and Victoria suffered from dramatic gas shortages for quite some time. Basically, the explosion occurred because the temperature in the unit that exploded got below the embrittlement point of the material from which the unit was made. (In other words a design fault – either the unit should have been built from material that would never reach its embrittlement point and/or unit should have been protected by rupture disks that would burst at the appropriate temp/pressure combination and direct the escaping gas to the flare. It is also worth noting that the particular problem hadn’t occurred since the plant started operation 25 years earlier.
    So it was a bit startling to see in the papers that one of the main recommendations was that “the control room operators be better trained”. Anyone who has operated a control room when things start to go wrong understands that you cannot depend on the operator realizing how serious what is happening is or the correct response. But this is what the lawyers concluded. (As a matter of interest the operators had been struggling with hydrate build-up all day and probably saw the problem as “keeping the plant running” when problems started in the unit that failed.

    The second one was the inquiry into the black Saturday fires. The problems with this inquiry were discussed at length in
    this LP post The inquiry reinforced the case for having someone other than lawyers running inquiries in areas where they haven’t a clue about who is responsible for what during an emergency and the practicalities of large scale evacuations during bush fires.
    Now this one. Miles better than the Black Saturday investigation but, as Desipus put it so well they didn’t understand what the manual was and wasn’t and the relationship between the manual and what the engineers were really supposed to be doing.

  27. desipis


    The manual dictates in each strategy except W4 a maximum allowable release, but not a minimum.

    Reading through the strategies (particularly W1A to W1E) the alignment of the “maximum release” and the goals of limiting combined flows gives me the impression that the maximum release is simply where the flow from the dam itself (ignoring any other sources) is enough to cause the goal to be lost (i.e. water over the particular bridge). Once you’re at the point where the flow from the dam itself will cause a crossing to become untrafficable it’s pointless having a strategy where the primary purpose is to maintain the trafficability of that crossing. It’s the opposite to the situation I described above, where instead of lower objectives governing outflows in the higher strategies, you could have higher objectives governing outflows in lower strategies effectively rendering the strategy obsolete.

    I recall when reading through the report that somewhere one of the engineer’s made the point that the strategy would be (in part) determined by the outflow of the dam (despite the apparent contradiction the commission pointed out). I think this is what he might have been getting at. If you’re already releasing water from the dam to deal with risks to the higher objective of protecting Moggill or Lowood (or urban areas) over the course of the flow event, it’s an academic exercise to determine whether the dam level means you’re operating under W1 or W2 (or W3) because making some lower objective “primary” doesn’t impact the fact that the higher objectives would govern releases. If you’re in a situation such as a major flood event I think it’s reasonable to deal with such distinctions after the fact (if at all).

    I think there’s certainly a case to be made for improving the manual. However, given it was likely written by engineers for lawyers it’s not all that surprising it ended as much of a confusing mess as the commission’s report on the matter.

  28. desipis

    John D, thanks. Since I’ve begun to study law I’ve been considering the ability of judges (as essentially lawyers) to deal with complex technical issues. It wouldn’t surprise me if the issues you identify with such inquiries extend to over the whole judicial system. I think there might be an argument for creating independent judicial bodies for major academic fields consisting of technical experts who are responsible for determining questions of fact (or standards of professional conduct) in relevant cases, while leaving matters of law to the traditional “law” judges.