After a couple of test posts, the blog began to wend its way through the online world on March 17, 2005, so it’s a very old beast in internet years.

We collectively feel seven years is enough.

I think LP played a significant role in stimulating political debate over the course of its life, and acted as something of a catalyst for a lot of good things in the spaces of new media and public discourse.

To large degree, though, the caravan has moved on.

There’s no longer the same need for a hub for political discussion, as lively debate has migrated to social media platforms such as Facebook and Twitter, and as the space for opinion and analysis around the shop has widened. The fact that the ‘blogosphere’ in Australia is no longer a term that makes much sense is an indicator of that change.

To a large degree, LP was a victim of its own success, adopting a role as a sort of ‘blog of record’ where the daily political news could be analysed and dissected. I think this was an important thing for some time, particularly during the last of the Howard years. However, LP bloggers, I think, became increasingly uneasy about this focus, wondering whether we weren’t inadvertently feeding the media cycle beast.

I am convinced there’s a role for a more curated and conciously counter-cultural focus on policy, shifts in the lived experience of our public culture, and serious examination of flashpoints in the battle between reason and untruth.

Some of us tried something in that vein with our recent collaboration between FAQ Research and Crikey, Coal Seam Gas: Behind the Seams. I think we’ve also contributed meaningfully to the achievement of those goals through our coverage and analysis of climate science and climate policy here.

We have come to the conclusion that while we’d like to reorient our perspective as writers and analysts, LP is not the place to do it. The blog has its own momentum (and its own inertia), and it’s not an easy thing to turn around.

Several LP bloggers will be striking out in new directions, some as yet in the process of coalescing. If you’re interested, and I hope you will be, in following and participating in our individual and collective efforts with others, I’d encourage you to ‘like’ our Facebook page, where we’ll direct people to other things we decide to do.

Anyone interested in what I might do media-wise might also like to sign up to the FAQ Research e-newsletter, and ‘like‘ us on Facebook. I think there’ll be a new media project down the track, combining research articles, multi-media and blogging and social media, but, again, spadework needs doing. I think it’s important to focus on some very profound issues of science, change, policy and risk, and the massive impacts on our society and culture they shape. I also think a sharper focus on the dissemination and production of social scientific and cultural knowledges is key.

Should you wish to make a donation to support such an endeavour, there’s an IndieGoGo fundraising page here. Any serious media effort requires funding, covering hosting fees, design, and most importantly, some small compensation for the time of the contributors. You may also wish to express your thanks for our work over the years since 2005.

In the meantime, when I have the impulse to write, I’ll be updating my personal blog, Sed Probates Spiritus, and other LP bloggers who start up new projects may update this post while comments are open. If you’re looking for other places for independent Australian political commentary, you can’t go past John Quiggin and Club Troppo (where my own blogging trajectory began) and Crikey and New Matilda. And of course, there’s the excellent Hoyden About Town.

I don’t think it’s appropriate to the history and spirit of this blog to just keep it ticking over while our energies are directed elsewhere (and it does take a lot of energy to do this sort of work).

Many, I suspect, will feel sad at this blog’s closure, but it simply isn’t and can’t be the vehicle for what the times demand now, and into the future.

It remains for me to thank, from my heart, all those who’ve shared the journey: bloggers, guest writers, commenters, all. Your enthusiasm and talents have been, and are, wonderful and the archive of this site, as well as your future endeavours in working towards a much better standard of public discourse in this nation, are their own tribute.

It would be wrong to thank people by name, but you know how grateful I am. This blog has been a large part of my life for a very long time, and it’s hard to say goodbye, but new beginnings are also an important thing in life.

Comments will remain open for a short time, but then be closed permanently.

Peace be with you all!

Update: Robert Merkel has a new blog at A Bent Ghost.

Update: [by Kim] The Pirate Queen’s Panopticon is moderating your interwebz here. I’m also hoping to be part of the new media venture Mark refers to in this farewell post.

Courier Mail banner headline

As I outlined in the first post, in February this year the Queensland Floods Commission of Inquiry reconvened as a result of reporting in The Australian by Hedley Thomas which suggested there had been a major breach of the flood manual for the operation of the Wivenhoe and Somerset Dams (7th revision) and that there had been a cover-up to disguise the fact.

We saw in the subsequent post that the non-compliance found by the Commission was not particularly consequential, so the question remains as to what upset the Commission so much that they referred flood engineers, Robert Ayre, Terry Malone and John Tibaldi to the Crime and Misconduct Commission to see whether offences had been committed against the Criminal Code and the Crime and Misconduct Act, 2001.

When Tibaldi, the author of the Flood Event Report (download from the bottom of the screen) took the stand it was a brutal attack with a senior barrister lunging for the jugular and in the screaming headline “WE”VE BEEN DUPED” in the Courier Mail.

In my opinion, being attacked in that manner by an organ of the state is as bad or worse than being taken out the back and beaten up. Justice Holmes should not have allowed it and people suffering such attacks should be able to sue for damages. Inquisitorial questioning of that kind is not designed to discover the truth. Rather it’s purpose is to bully and trick the presumed guilty into incriminating themselves. That methodology actually downgrades the quality of some of the evidence assembled in the Final Report, having been extorted under duress.

Moreover, the Commission showed little appreciation of what working long hours under extreme stress does to cognitive ability and memory. Nor did they seem to understand that memory is imperfect and suggestible even without stress. They had no concept of days merging into each other under stress.

After that spray, I have to say that I agree with some but not all of the Commission’s conclusions, for example, the need for an improved review process. And there was indeed a legitimate issue about how the engineers represented their decision-making processes in the Report. But the Commission, I think, overestimated the seriousness of what happened and completely misinterpreted the issue of motive.

How the engineers operated

A large part of the problem was that the engineers did not make overt decisions about which of the “W” strategies they were in, or so they said quite consistently in evidence this February. The engineers thought and acted in relation to the information they got from rain gauges, stream flows, dam input and output flows, dam levels and conditions outside the catchment areas, modelled to forecast a stream flow at Moggill 16 hours after dam releases.

What they were meant to do was to pause after gathering the data, check which “W” strategy they were in, and then make decisions. What they did was to go directly to making decisions on the appropriate release levels in relation to the main goals or markers contained in the “W” strategies. They were operating at the next level of detail. The “W” strategies were filled in later as part of the reporting. That’s the way it had always been done, from back in the 1990s. This was confirmed by Mr Peter Allen, the Director of Dam safety in DERM who had in fact worked with some of the engineers on floods in the 1990s.

That being said, there is little doubt they knew when W1 had been left behind and the main concern became flooding in Brisbane. They also knew when it was time to concentrate on saving the wall.

How the engineers reported about how they operated

Unfortunately in the inter-agency communication (eg between the flood operations centre, Seqwater, the Water Grid Manager, DERM and the Minister) during and soon after the event, there was comprehensive confusion about what strategy operated when, and when the switches were made. One donkey (not one of the flood engineers) even said W1 when he should have said W3 and said W3 when he should have said W4. But there was an assumption by all, it seems, that W2 was in the mix because it was thought of as a transition strategy from W1 to W3.

W1 is clear. The dam level is over the full storage level (FSL) of 67m and not yet 68.5m. When the level hits 68.5 or the Mt Crosby Weir Bridge goes under, which it does at 1,900 cumecs (it’s just above where the Bremer joins) you must exit W1.

W3 is clear. Dam levels are between 68.5 and 74m. The main priority is to prevent “urban inundation” in Brisbane. In the manual the marker for this is 4,000 cumecs at Moggill, which is where the suburbs started when the dam was built and just below where the Bremer joins.

W4 is clear. The dam is approaching or over 74m and the prime concern is to protect the dam wall.

W2 is not clear. It is an optional strategy and can be bypassed. A limiter of 3,500 cumecs at Lowood is introduced as well as 4,000 at Moggill. This is a bit curious because Lowood is below the Lockyer Creek junction but probably a good 40km above Moggill which is below the Bremer. When you have 3,500 at Lowood, 4,000 at Mogill would not be far away. If Lowood (population about 1,000) is important, why not mention it in W3? Even more curious is the requirement that releases from Wivenhoe must be below the natural flow at Lowood, excluding water from the Wivenhoe. There is a similar clause relating to Moggill. (The statement in the manual is actually ambiguous, but the alternative meaning is nonsensical.)

I’m convinced in rereading the chapter that the whole pack of them, Tibaldi especially, clean forgot about that relative stream flow clause in W2. Tibaldi on Saturday 15 January at short notice wrote a report in two hours for the Minister. In it he had them in W1 until late Sunday. He later said he had gotten it wrong. He hadn’t slept for a very long time and was so tired he had no memory at all of the day he wrote the report. The Commission said, no, a competent engineer would remember, no matter how stressed and fatigued he was (p494). The report was evidence that his true perception back on Jan 8 and 9 was that the dam was being operated in W1. That was the “only reasonable conclusion”.

Two weeks later, when Tibaldi was preparing the Flood Event Report he noticed from the records that at 8am on Saturday the calculated natural flow at Lockyer was 500 cumecs when the Wivenhoe release was over 900 cumecs. Too much water was being released to fit with W2.

Then he did something really dumb. In the report in Chapter 10 of the Flood Event report he set out a spreadsheet which identified times, then in a column on the left the “W” strategies chosen, followed by a column with the explanations of what they did, and then a column with ‘manual requirements’ on the right.

Unfortunately in the column where he wrote the explanations of what they did he had them operating exactly as they didn’t, making conscious choices about “W” strategies at the appropriate times. Then he invented a W2 bypass choice which never happened and wrote that up. Pure fiction, I’m afraid.

I think the engineers operated according to the main game as laid out in W1, W3 and W4 at the next level of detail. The “W” thing as such really wasn’t important so he didn’t see it as a big lie. It was essentially a communication issue, which wasn’t picked up by the others who checked the text, or by the four formal reviewers.

Then he compounded the dumbness. Tibaldi in giving evidence to the Commission last April waxed eloquent to the Commission as to how they operated in a way that he later had to admit they didn’t. Ayre, when they checked what he said against what he said last year was found to have invented a story. There were suspicions of collusion. I suspect his memory was vague, but under pressure came up with an explanation that he convinced himself was the way he remembered it. Malone was also implicated, but Ruffini got off.

Why? Ruffini got off because it seems the Commission gave up on him, describing his evidence as rambling and discursive and unable to grasp the question he was asked. Ruffini was very upset at the time because someone told him he couldn’t look at a particular spreadsheet before he gave evidence. His stressed state of mind perhaps saved him.

Judicial commissions are understandably upset under circumstances like this. But they can lack perspective at this point. I think it may have led them to a bias against the engineers when examining the issue of substantive manual compliance. A stern rebuke was certainly warranted, but delivered with respect, and a recommendation that someone with editing skills work on the report before it is released. It would have been simple to reorganise the columns so that what the engineers did and why took prominence, then a match with manual compliance indicated in a column on the right.

In any event their treatment of the miscreants in the witness box was a form of punishment in itself, if not revenge.

Substantive compliance with the manual

In the second post from the third paragraph on I gave an account of how Ruffini at 4.50am on the Saturday authorised a change of the gate settings to meet the forecast situation when the dam would cross the threshold of 68.5m thus requiring a strategy above W1, which it did at 8am. The Commission had decided that conscious choice of strategy was required by the manual which led them to obsess about what was in the minds of the engineers. They continued to obsess about what the engineers had in their minds about the “W” strategies when the engineers consistently said they didn’t think that way.

Tibaldi would have done better to nominate the transition to W3 as at 4.50am rather than 8am but the distinction is trivial. The fact that Ayre at 8am didn’t make a decision which had already been made somehow became significant for the Commission. Ayre did nothing, they said, to demonstrate the move from W!. Actually, the option of changing nothing is open under W3.

Also during the following 36 hours the Commission observed that there were several references to W2 and none to W3. The Commission did understand that the dam releases were compatible with with both W1 and W3 and that there was a legitimate concern for the two higher level bridges. The Commission didn’t seem to recognise that 4,000 cumecs at Moggill, the marker for urban inundation downstream, simply wasn’t in play, whereas the higher level bridges, a mandated concern under both W2 and W3, were. Moreover, in five of the six situation reports during the time in question impacts on Brisbane are mentioned, in three cases in millimetres at the Port Office. The exception was Sunday morning which reported the dam level falling.

In the end, after a 50 page tortuous tour of the engineers’ minds by a Commission clearly unqualified in psychology, the conclusion that the dam was operated in breach of the manual comes as a jolt on p504. It seemed to turn on a lack of clear evidence of a choice to leave W1. I think there was such a choice. It happened at 4.50am on the Saturday, but without bells, whistles and bright lights.

The Commission used the balance of probabilities as the standard of proof, along with the notion that no other reasonable explanation was available. I think their finding that the engineers were in breach of the manual is at the very least unsafe.

The engineers ability as engineers was not seriously in doubt. Their actions were found by Babister to be ‘very close’ to the maximum achievable within the constraints of the manual. The Flood Event Report stands as a technical document. So what exactly is the problem here? The issue is about communication, not engineering.

W2 and the manual

The Commission obsessed about what was really in the engineers minds with respect to “W” strategies, whereas in the February hearings they were quite consistent in saying that they didn’t think much about that at all. But the Commission had made a key decision 50 pages earlier (section 16.3) that an engineer would make better decisions if they made a conscious choice of “W” strategy, so the possibility existed for the decisions they made to have been better than good.

I think the engineers were always aware of which of the three main ball parks they were in. The problem is that W2 does confuse the issue.

Take a look at how the manual treats the issue of relative stream flow. It’s on page 27, that’s at 32 on the pdf counter, but for your convenience I’ve done a screen shot of the relevant part:

Consider this sequence:

the combined peak river flows should not exceed, at Lowood, the lesser of the natural peak flow excluding Wivenhow Dam releases, and 3,500 cumecs.

It’s nonsense, but most seem to take it to mean that the releases from Wivenhoe should be less than the natural flow calculated at Lowood excluding water from the Wivenhoe. W2 was variously called “confusing”, “ambiguous” and “somewhat redundant” in evidence. Here’s why W2 may be considered redundant.

By definition if you are exiting W1 you are dealing with a flood in the Wivenhoe. The time you would consider keeping Wivehoe releases below what was coming down Lockyer Creek would be if the rain had eased off in the Wivenhoe catchment but was flooding down Lockyer. In that case you’d hold water in the Wivenhoe to let it pass. But if that happened you’d do it any way under W3.

If you had the option of bypassing W2, why wouldn’t you? To me the evidence is that they routinely ignored that little clause and eventually forgot it was there. Tibaldi as a Seqwater engineer (they own the dam) had put a flow chart into the manual, which simply elides that little conundrum and produces a path which would nevertheless mostly land you in W2 rather than W3. Here’s the flow chart, which is on p28 by the pdf counter of the manual:

Figure 2: Strategy selection flow chart

If Tibaldi had been aware of what W2 actually said he would never have inserted that flow chart. In any case it is simply wrong. And it certainly would be a distraction to be thinking about this conundrum in W2 when you are dealing with a flood.

I suspect W2 was inserted as a concession to Lowood lobbying generated either by the psychology of townspeople finding themselves downstream from a massive dam with an 80 metre wall or by local farmers who saw their paddocks being flooded by the whims of engineers concerned with the convenience of urban dwellers downstream. To me it has the look of an awkward compromise and should be reviewed..

It needed a review and it got one. It’s a beauty, as you’ll find in the Ninth Revision of the manual released last November. W2 is still there (see p28). The conditions are the same as for W3, but the intent is different. Try this for size:

The intent of Strategy W2 is to limit the flow in the Brisbane river to less than the predicted flows at Lowood and Moggill excluding Wivenhoe Dam releases. This means that releases of water from Wivenhoe Dam should, in most circumstances, be managed to limit the flow in the Brisbane River at Moggill to less than the predicted flows at Lowood and Moggill excluding Wivenhoe Dam releases, while not allowing the radial gates to be overtopped.

It did my head in! By releasing nothing from the dam you still couldn’t get the flow in the Brisbane River down to below where it would be if you where releasing nothing.

In the conditions, they’ve introduced the notion of a forecast level as well as an actual. I think if the dam is actually between 68.5m and 69.5m and also forecast to be between 68.5 and 69.5m, you have no strategy. That’s exactly where some said there should have been aggressive releases.

So I went over to page 29 to look at the pretty flow chart. That did my head in even more. No mention of Lowood. No mention of a maximum release of 3,500 cumecs. But if you answer “no” to four questions in a row you get to stay in W2 whether you answer “yes” or “no” to the fifth. And here’s a new level – 3m predicted above FSL (full storage level), not 2.5 as on page 28.

Also you get to choose which strategy you go into according to what release rate you deem necessary. I thought it was supposed to be the other way around.

If “disruption and damage to urban areas below Moggill” start at 2,000 cumecs, I thought it would be worth a major trigger point, rather than just a comment.

On the W2 flow chart if the predicted peak flow at Moggill is less than 2,000 cumecs or more than 4,000, excluding water from Wivenhoe, you go to W3. So W2 must be for when the flows at Moggil, excluding Wivenhoe water, are between 2,000 and 4,000 cumecs. This isn’t clear on page 28, where they give the maximum release available as 3,500 cumecs under W2.

From the W1 flow chart, W2 is no longer optional.

I’m not an engineer and thankful for that. It’s quite possible I’m missing something but I’d never want to operate under such a manual. I’d prefer broad scenarios with identified parameters and flexibility within. Revision 7 would have given us that if you took out W2 and tidied it up a bit. I’m genuinely interested in what engineers make of Revision 9.

*we expect this basic courtesy towards other participants: allow the Salon to be a space for something different to be discussed. i.e. do not threadjack the Salon with comments that better belong on other active threads.

Try our roundtables index for recent lively discussions or browse our archives for topics of interest.

In this post I’ll address the question of whether the engineers could have done better, or to use the Commission’s terms, examine whether any non-compliance with the manual was consequential.

As I reported in the earlier post, the Commission found that the dam had been operated in strategy W1 in non-compliance with the manual for about 36 hours from 8am on Saturday, 8 January. The dam crossed the 68.5m threshold at 8am on the Saturday. Three hours earlier, at 4.50am, John Ruffini had authorised increased outflows of about 1,200 cumecs, as against 351 at 5am. Inflows at 3am were 1,300 cumecs.

1,200 was achieved by 2pm with inflows about 1,800. By 10pm outflows exceeded inflows, 1,242 to 1,091. This situation pertained until 10am on Sunday, when inflows became 1536 as against outflows of 1,332. One of the difficulties for the engineers is that releases of less than 1,900 are compatible with strategy W1. This threshold was not crossed until 8pm on Sunday. It should be noted that there is no minimum release rate specified for W3, or indeed for W1 and W2.

The engineers claim that Ruffini’s decision at 4.50am constituted a move out of W1 as it was designed to deal with the dam level rising above 68.5m threshold. Which it did, and the dam level fell for 12 hours from 11pm Saturday. The Commission was uncharitable about this because the Ruffini’s releases were based on modelling done on Friday by Malone, when the lake level was not projected to go above 68.5. However, Malone’s release rates were not implemented. Ruffini chose to do so in the light of the new situation, modifying them slightly. The Commission obsessed with the fact that Ayre, who came on duty at 7am, changed nothing at 8pm, the time the level past 68.5 and the time nominated by the Flood Event Report as transitioning to W3.

Much of the problem here is that the engineers did not have the global “W” strategies front of mind, but operated at the next level of detail. In particular they didn’t discriminate at all between W2 and W3, where the broad parameters are almost identical, and forgot about the fine print, where the differences are quite stark. However, anything you can do under W2 you can also do under W3, so in a sense it is redundant. Their practice was to work the dam and fill in the fine detail at the reporting stage.

The Commission’s view was that engineers are likely to make better decisions if the have the global situation in mind as represented specifically by the “W” strategies of the manual. This is questionable, as they had some external expert advice to the effect that it didn’t matter. In addition, their independent hydrologist, Mark Babister was comfortable with manual compliance, given the ambiguities of the manual. What is relevant here is that if the engineers had consciously chosen W2 on Saturday they would have been obliged to reduce the outflows from Wivenhoe to less than the 550 cumecs, which was the assessed natural flow at Lowood, sourced mainly from Lockyer Creek, excluding Wivenhoe releases.

Now take a look at the graph depicting the inflow and release summary for the dam from the Flood Event Report of March 2011:

Figure 1: Wivenhoe Dam flood profile

Hedley Thomas’s contention that the dam was mismanaged is based on the notion that a more aggressive release of water from 8am on Saturday could have ramped up the light blue line more steeply. This would have lowered the dam level enabling a smaller peak in the light blue line later, which determined the subsequent height of the flood.

Babister modelled a scenario where enough was released from 8am on Saturday to produce a total flow of 4,000 cubic metres per second (cumecs) at Moggill, that being the indicator for urban inundation (see Scenario 7 in Section 16.14.3, or p525 of the Final Report). He found that as a result the Port Office peak would have been reduced by 0.6m. So the flood would have been 4m, still above the major flood level, which I think is 3.6m:

Figure 2: Port Office flood peak

Graph from modelling by Sinclair Knight Mertz (see Section 16.14.2 of Final Report).

A clearer view of the pattern of the actual flood is shown in this graph from the Flood Event Report (Figure 6.5.13):

Figure 3: Port Office flood

It is relevant here to show the tide levels for the period. This graph is Figure 6.5.14 in the Flood Event Report:

Figure 4: Tides at Whyte Island

Whyte Island is near mouth of the Brisbane River. It seems from the above graphs that the normal tides commonly take the river to the point of minor flooding in the tidal reach.

It’s also worth bearing in mind that the river spreads and flattens out as it goes. The flood levels at Moggill, Jindalee and Oxley were 17.6m, 13.1m and 8.3m respectively. Babister’s modelling showed that there would be a reduction of 1.3m at Moggill and Jindalee and 0.9m at Oxley. This is to me a surprisingly small amount. In many cases the amount of damage to a house with a metre or so less water would be minimal.

Babister also found that such an aggressive release would have been “highly risky”. The 4,000 cumecs at Moggill guard rail in the manual is problematic. At least two of the engineers, Ayre and Tibaldi, knew that significant water problems started with 2,000 cumecs at Moggill. The Flood Event Report recommended that 2,000 be considered for inclusion in a revision of the manual. This was taken up by the Commission’s Interim Report and incorporated into the Ninth Revision of the manual published last November, not as a marker between strategies, as I think would have been appropriate, but as a point to keep in mind.

2,000 cumecs also happens to be the point at which the Fernvale Bridge goes under. That bridge is not primarily a connector between rural areas. It is on the Brisbane Valley Highway, which is one of three ways of getting from SEQ to Central Queensland. From memory all three were cut by floods when the Fernvale went under. Between Fernvale and Moggill the Bremer joins the Brisbane, so 2,000 at Fernvale is a higher bar than 2,000 at Moggill.

Once the significance of 2,000 cumecs at Moggill is understood the matter of whether the engineers could have done better is easily resolved. At 8am on Saturday as the dam hit 68.52m the flow at Moggill, with water from the Wivenhoe excluded, was assessed as 770 cumecs, deemed the “natural flow”. The engineers had decided to increase the release rate to 1,200 cumecs which was achieved at 2pm. The BOM had forecast increased rain in the Wivenhoe catchment but for the weather system to move south over the Lockyer and Bremer catchments. Estimating the flow at Moggill in 16 hours time is not an exact science so there was little room to move before you could expect complaints downstream and people perhaps ringing their lawyers.

The difficulty with 4,000 cumecs at Moggill is further highlighted by a phone call made by the Brisbane City Council to the engineers on Monday morning. The flood engineers were told that according to the BCC damage tables 3,500 cumecs at Moggill would see 322 properties fully inundated and an impact on 7,000 properties. 3,000 cumecs would see 2,600 properties impacted in some way.

Babister’s modelling was done without consideration given to rainfall forecasts. I’m not sure what difference that makes.

It is relevant here that on Friday at 4pm the 24-hour forecast was for an average of 25mm across the catchment. Only 6mm fell. The forecast at Saturday 4pm was for 40mm. A total of 80mm fell.

Of course major damage was eventually done in Ipswich, where water in the Brisbane River backed up the Bremer for 15 kilometres. Ipswich people have been among the most vocal in criticising the engineers. No modelling was done by Babister to show what difference different release strategies would have made to Ipswich. The class action lawyers may have to work that one out for themselves.

As far as I know no modelling has been done which shows the conditions that produce damaging backup in Ipswich. This should have received greater attention from the Commission.

There have been no significant complaints about how the engineers operated the dam from Sunday evening, but there were suggestions that they could have moved faster on Sunday in response to overnight rain. Inflows were as low as 773 cumecs at 8am on Sunday, but by 3pm when they had a meeting of all four engineers the rate had increased to over 4,000.

Given the rain forecasts (the 24-hour forecast of 10am was exceeded by 300%), the action taken was reasonable. The notes of the meeting state, in part:

The rainfall system is currently in the N-E part of the catchment and expected to travel south over the next 24-36 hours according to the BoM forecasts. This has the potential to significantly increase flows in the Lockyer Ck & the Bremer River which potentially could close Fernvale Bridge and Mt Crosby Bridge and increase risk of flooding in Lower Brisbane. Releases from Wivenhoe Dam will be maintained at the current level of ~ 1,400 cumecs. If required, release from Wivenhoe will be reduced to contain the flow in the Mid-Brisbane to 1,600 cumecs and 3,000 cumecs in the Lower Brisbane. At this stage it is anticipated that levels below 102.5 in Somerset and 72.5 in Wivehoe can be maintained.

Remember even with the unexpected overnight rain on Monday morning Tibaldi was able to promise the BCC to try to keep the flow at Moggill below 3,500. At that stage there was every prospect of reasonably containing the first peak shown in Figure 1 (inflows peaked at 8pm). The second peak was kicked off by heavy rain in the Wivenhoe catchment early Tuesday morning. The water from the Toowoomba/Lockyer cloudburst would have started arriving at the Brisbane River junction from Tuesday afternoon.

Moggill peaked with 12,095 cumecs at 11am on Wednesday, just 16 hours after the peak release of 7,464 from the Wivenhoe at 7pm on Tuesday. The black swan event, if you like, was a combination of the Toowoomba/Lockyer downpour and intense heavy rain in the Wivenhoe catchment arriving in the Brisbane River at much the same time.

Perhaps the Engineers, on Sunday, should have taken account of the risk of higher rainfall than was forecast on Sunday. But the Flood Event Report rates the whole event at between 1 in 100-year and 1 in 2,000-years. So that too is an inexact science and I’m not sure that reminding the engineers of those odds would have inspired them to act differently. As the events unfolded they did seem to have access to records of what happened in previous floods and be mindful of precedents.

There was also a risk that the rain system might weaken or go somewhere else. Quite recently we had a forecast of 60-100mm falls in Brisbane City. We got about 6mm from memory, but they got 300mm about 100km north of here. That kind of thing is not uncommon in this part of the world, like several times a season rather than 1 in 100 years or more.

To sum up, I think the engineers did pretty well. Indeed the Commission seemed to accept Babister’s opinion that the “flood mitigation effect was ‘very close’ to the maximum achievable within the constraints of the manual.” Thomas’s comment about “mismanagement” is I think risible.

I’ve addressed the issue of whether the engineers could have done better first so that you could see that any non-compliance was of little consequence to flood mitigation outcomes. I think the underlying problem of how the engineers operated in relation to the manual turns on the nature of the W2 strategy as formulated in the 7th revision of the manual, and the confusion it caused. I’ll take a look at that in the final post, which addresses how the engineers fell foul of the Commission.

It should be noted that the Commission’s standard of proof was on the balance of probabilities, not beyond reasonable doubt.

Detail of a unicorn on the grill in Geoffrey Fule's cookbook, England, mid-14th century (London, British Library, MS Additional 142012, f. 137r).

Experts believe that the cookbook was compiled by Geoffrey Fule, who worked in the kitchens of Philippa of Hainault, Queen of England (1328-1369). Geoffrey had a reputation for blending unusual flavours – one scholar has called him “the Heston Blumenthal of his day” – and everything points to his hand being behind the compilation.

Please share any bits and pieces you have come across recently that have surprised, delighted, intrigued or otherwise positively engaged you.

NB: the weekly whimsy thread is a stoush-free zone

In February the Queensland Floods Commission of Inquiry reconvened as a result of reporting in The Australian by Hedley Thomas which suggested there had been a major breach of the flood manual for the operation of the Wivenhoe and Somerset Dams (7th revision) and that there had been a cover-up to disguise the fact. The Commission’s Interim Report of August 2011 had been thorough and sympathetic. The Commission noted such things as non-compliance in relation to weather forecasts (the forecasts were so erratic the engineers ignored them in determining gate settings, contra the manual). They also noted deficiencies in recording decisions and actions in real time. They made a host of recommendations about improvements (see Recommendations relating to Chapter 2) but the impression was of a job well done. Chapter 2 (Section 2.7) remains perhaps the best blow by blow account of how the flood was managed.

Chapter 16 of the Final Report does in fact find that the manual was breached from 8am on Saturday 8 Jan for about 36 hours until the evening of Sunday 9 January. It found that the engineers were operating in strategy W1 rather than W3 as claimed in the Flood Event Report of 2 March 2011 (downloads at bottom of screen). It also found that three of the engineers knowingly misled the Government and the Commission about the “W” strategies. It recommended that Ayre, Tibaldi and Malone be investigated by the Crime and Misconduct Commission in relation to the brief to the Minister of 17 January 2011, the Flood Event Report of 2 March and other documents, as well as in testimony to the Commission to see whether offences had been committed against the Criminal Code and the Crime and Misconduct Act, 2001.

Serious stuff. Hedley Thomas in these articles was well-satisfied with his work. He spoke of “mismanagement”, a lack of competence and assumed that compensation was clearly due to flood victims who had had their homes and properties needlessly damaged. Here Thomas, presumably with presumed hydrological expertise not available to the Commission, has gone beyond what they said. They had asked an independent hydrologist, Mr Mark Babister, to review the flood documentation and reporting and to undertake modelling of alternative strategies. Babister’s report had become available just as the Interim Report was to be printed. His finding could not be incorporated in the document, but a statement was inserted saying that nothing in his findings conflicted with the Commission’s interim report. He found that:

the flood engineers managed Wivenhoe Dam so that its flood mitigation effect was ‘very close’ to the maximum achievable within the constraints of the manual.

Furthermore, he said that an aggressive early release would have been “highly risky” and would have used the Wivenhoe as a flood amplification dam rather than a flood mitigation dam. That’s all from the Final Report. The Commission did not back off Babister’s findings as alleged by Thomas. What they did say was:

Ascertaining the practical result of acting more quickly also is subject to the uncertainties inherent in the modelling; but again, the possibility exists of at least some improvement in the flooding outcome for Brisbane and Ipswich.

The possibility of “at least some improvement”. And if the class action lawyers want to know exactly which homes and buildings would have been saved they will have to do their own hydrological modelling. The models Babister used were not sophisticated enough to show this, and in any case his technical modelling has not been made available.

The problem, you see, was that the engineers thought and acted in relation to the information they got from rain gauges, dam input and output flows, dam levels and conditions outside the catchment areas, modelled to forecast a stream flow at Moggill 16 hours after dam releases.

What they were meant to do was to pause there, check which “W” strategy they were in, and then make decisions. What they did was to go directly to making decisions. The “W” strategies were filled in later as part of the reporting. In doing so they followed the same methodology that had always been employed from back in the 1990s.

The Commission took the view that the engineers would make better decisions if they operated a different way, that the “W” strategies be consciously chosen and be front of mind at all times. What’s more, compliance with the manual demanded it, they said.

I’ll come back to these issues in a second post. In this one I’d like to give an account of the actual event, which was a good deal more threatening than most realise.

The Wivenhoe Dam in context

The Wivehoe Dam catchment drains some 7,000 square kilometres of the Upper Brisbane River. It includes the Stanley River, a tributary flowing in from the north which is dammed by the smaller Somerset Dam. The Locker Creek draining some 3,000 square kilometres joins from the west just below the Wivenhoe and just above Lowood. The Bremer River draining some 2,000 square kilometres flows through Ipswich and joins just above Moggill. It takes about 16 hours for water to flow from the Wivenhoe to Moggill.

A flow of 4,000 cubic metres per second (cumecs) at Moggill is taken in the manual as a marker for urban inundation downstream in Brisbane.

You can get an overview of the geography from the two maps in this post. The total average rain during the flood event is given in this map:

Figure 1: Flood rain

Three points to note. First, the Pine River is an entirely separate system, not a tributary of the Brisbane River. Second, there is a slab of country in the segment designated “Lower Brisbane” which would also drain into the river above Moggill. Finally, the cloudburst that flooded Toowoomba and devastated Grantham and the Lockyer Valley doesn’t show up in the overall. That might be because there was no rain gauge on the eastern escarpment of the Toowoomba range. The other catchment numbers might also be underdone as the engineers found that there was more water coming at them than was implied by the modelling based on the gauges.

A monster flood

In the 2011 event 2,650 gigalitres of water flowed into the Wivenhoe dam. The comparable figures for 1893 and 1974 would have been 2,740 and 1,410 respectively. In February 1999 there was an event with 1,220 GL that most people don’t remember, because the Wivenhoe had been built and coped with it. Sydney Harbour holds about 500 GL. Here is a graph showing historical flood levels:

Figure 2: Brisbane floods

That’s at the Port Office in the city reach. The 2011 flood was 4.6 metres, but the Flood Event Report tells us that it would have been two metres higher without the Wivenhoe. Later modelling by Sinclair Knight Mertz suggested about 1.2m higher.

In fact we had a flood in two parts, 30 hours apart. The dams would have coped pretty well with the first, but were overwhelmed by the second. The pattern is shown in this image from the report:

Figure 3: Wivenhoe Dam flood profile

The Executive Summary of the Flood Event Report (well worth a read) tells us that the maximum flow rate of the first peak has been estimated to be 200% of the 1974 event and the second 230%.

The story, in brief

The flood operations centre was established, as is required, on 6 January when the Wivenhoe Dam reached the full storage level of 67 metres. Malone and Tibaldi were engineers from Seqwater, which owns and manages the dam. Ayre was a senior engineer from Sunwater, which was contracted by Seqwater to operate the centre. Ruffini was a senior engineer from DERM. They were supported by 13 flood officers at various times. My impression is that the flood operations centre was in the Brisbane CBD.

Strategy W1 was then automatically in operation on 6 January, where the focus is on the impacts on rural life below the dam, principally the river crossings. By Friday night the five lower crossings were inundated, leaving the Fernvale Bridge just below Lowood, which goes under with 2,000 cumecs, and the Mt Crosby Weir Bridge down near Moggill just above where the Bremer joins, which goes under with 1,900 cumecs. The dam level was predicted to rise above 68.5m, which triggers either W2 or W3. At 5am on Saturday morning Ruffini issued a gate opening schedule to cope with this situation, based on modelling done by Malone the previous day. At 8am on Saturday when the 68.5m trigger point was breached there was about 171 GL in the flood compartment, with inflows at 1,500 to 1,800 cumecs. Outflows were already above 900 cumecs and were increased to about 1,200 cumecs during the day.

Under both W2 and W3 priority must be given to preventing urban inundation, with 4,000 cumecs at Moggill the marker. Consideration is also given to lower level objectives, principally keeping the two higher bridges open. It should be noted that at 8am natural flows at Moggill, that is flows other than those from the dam release, were at 770 cumecs. At least two engineers (Ayre and Tibaldi) knew that water troubles in Brisbane start way lower than 4,000 cumecs at Moggill, in fact around 2,000 cumecs.

The increased releases saw the dam rise to 68.65m at 11pm then begin to fall again. Five of the six situation reports issued on Saturday and Sunday mention the predicted impact in millimetres at the Port Office in the Brisbane CBD. The exception was Sunday morning, which mentioned the dam level falling.

Overnight rain on Saturday night caused concern. It was decided to have a meeting of all four engineers on Sunday afternoon, with three present and Tibaldi on the phone. Malone compiled a scenario in preparation. 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. They decided to keep releases to about 1,400 cumecs with the possibility of holding back more water to allow the Bremer and Lockyer water to pass.

Although there was considerable rain to the south 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. It takes about 24 hours for the water to get to the Brisbane River so they had plenty of notice. At 8pm the engineers were advised that the rain in the Upper Lockyer was estimated at 600mm.

Monday was a wild day. It began with a phone call at 12.45am from the Brisbane City Council advising that according to their maps inundation would occur with 3,500 cumecs at Moggill, not 4,000. There was a second phone call from the BCC at 9.40am. I think it was during this one that the engineers were told that a flow of 3,500 cumecs at Moggill would fully submerge 322 properties and impact 7,000. The engineers agreed to try to hold it to 3,500, but had to abandon this by 3pm. By that time the situation had deteriorated to the point were they had to warn of possible Brisbane flooding and the dam was forecast to rise to 75.2m with rainfall forecasts included. Then they heard about the Toowoomba/Lockyer downpour.

And then as the clock went past midnight the fun really began.

The inflows fell until 2am on Tuesday when they reached 3,594, but the rain had increased. In the early hours of Tuesday morning it became apparent to the engineers that the water coming at them in the Wivenhoe catchment was more than the models indicated, based on the gauge readings. Estimates indicated falls of up to 700mm.

Inflows rose again to reach a new peak of 11,561 at 1pm. Meanwhile the dam level had reached 74m at 11am.

When the dam level is predicted to go above 74m the main focus must be on preserving the dam wall, because 244,000 people are said to be at risk. The first of three fuse plugs in the auxiliary spillway automatically opens at 75.7 metres, the third at 76.7. The wall is 80m.

When the inflows peaked at 1pm the dam was at 74.39m and forecast to go to 76.2. The Moggill flow was approaching 5000 cumecs and rising fast. The sluice gates at Somerset were closed to hold back a bit more there. Permission was gained to let the level at Wivenhoe float above 74m for a time. But even though the inflow was tapering the outflow had to be increased to a level above the inflows. This occurred at 7pm when inflows were 6,876 and outflows were 7,464. The dam peaked at 74.97 and tapered from there.

At 74m the dam was approaching 180% of normal storage capacity. At its peak it was 191% of capacity. The nominal peak flood is 225%, but the intent is to bring it back to under 74m as soon as possible without blowing the fuse plugs with releases as necessary, albeit with consideration of downstream damage.

The dam was above 74m from 11am on Tuesday until 6am on Friday.

The requirement is to drain down the lake to full storage capacity within seven days, which is why the outflows were held steady at about 3,500 cumecs during that process.

Moggill peaked at 12,095 cumecs at 11am on Wednesday 12 January. At the Port Office in the Brisbane CBD the flood peaked at 3.00am on Thursday 13. At that time the flood height was 4.6m and the flow 9,500 cumecs according to the Flood Event Report. During the week tides were up to half a metre lower than the previous and following weeks.

From this article:

An estimated 14,100 Brisbane properties were affected, while in Ipswich about 3000 homes were flood damaged. In Brisbane, the number of residential properties inundated totalled 1203.

The engineers decided to double team from Sunday night, with each doing a 12 hour shift every 24 hours. Later as they dealt with the dam level peak I understand all four were there at times, conducting reviews at 30 minute intervals.

As the floods rose in Brisbane three were cut off from home and slept in a meeting room. I’ve not heard how the flood officers who supported the engineers got on.

Weather forecasts

Precision in weather forecasting at these times is not really adequate to dealing with floods. For the first few days from 6 January actual rain was considerably less than the forecasts. On Sunday morning a 24-hour forecast of 50mm was issued for the catchment, whereas 149mm actually fell. On Tuesday at 4pm when decisions were being made to increase the outflows to above the inflows the forecast was for 75mm in the next 24 hours. In fact the system weakened and only 12mm arrived. Thankfully. And thankfully the engineers held their nerve and didn’t up the release in anticipation.

What difference would a 75% dam level make?

Dicsussion on this matter started immediately after the flood. I did a post on 21 January. My guestimate of the difference it would make was about 28cm (see this comment).

Turns out Babister’s modelling came up with 30cm (see Final Report Section 16.14.3, or p525, Scenario 3). But if the manual strategy trigger points were ratcheted down by 25%, the gain would be 60cm at the Port Office and 1.3m off the 17.6m level reached at Moggill. That’s perhaps worth doing, but I still worry, as did John D in the post, that in a drought you would leave yourself short of time to construct additional desalination plants.

Also 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.

But witness the instant reaction of law-and-order conservatives like Victorian Deputy Premier (and Police Minister) Peter Ryan:

“I mean hell will freeze over before I agree to do this,” he said.

“I think it’s more important that we concentrate as much effort and resource as we possibly can in relation to the policing and enforcement of it, although I appreciate there are criticisms about that approach.”

The imperviousness to expert opinion and painstakingly collected evidence should be an embarrassment to political conservatives – or, perhaps more accurately, the contemporary political right, whose connection with ‘conservatism’ is increasingly tenuous. But the fact that most of the political right is implacably opposed to reforming drug policy is the unpalatable reality. Furthermore, some members of the ALP genuinely share this view; others fear the electoral consequences of anything that could be painted by their political opponents as going “soft on drugs”.

Underlying this is the belief, repeatedly if briefly alluded to in the report, that the electoral consequences of a more rational drugs policy are likely to be severe, largely based on the fears of parents that a less punitive approach will encourage their children to partake.

The challenge for the advocates of sensible drugs policy is now political. The evidence is clear – but how do they get to a better policy given the implacable opposition of the likes of Peter Ryan, and the fear factor in sections of the community?

The arguments surrounding harm reduction are not new, and to date they have failed to achieve the goal of shifting policy. The evidence, sadly, isn’t enough. What’s required is a new way to frame the argument in terms that overcomes the fear of the wavering parents, to the point where Labor feels comfortable enough to pursue reform, because we’re clearly not going to get anything resembling sane drug policy from the right.

What that reframing is, I don’t know. My somewhat cynical guess is that anything that involves the well-being of addicts themselves will fall on deaf ears out in the waverer community. But what the winning message actually is, I don’t know.

But I’m pretty confident that the current presentation of the arguments won’t work, however compelling it is to anybody who looks at the issue in any depth.

The picture painted by Portas, needless to say, is not a rosy one. The charm of the traditional high street, with its local, independent shops and offerings is disappearing, and with it, the whole concept’s raison d’être. High streets across Britain are increasingly being peppered with failing or vacant stores, their essential uniqueness incrementally crushed by the omnipresence of large retail companies and supermarkets. If you are going to do your weekly grocery run at the local supermarket, why not go to the local satellite mega-market with its colossal car park, rather than struggle through the car-parking nightmare of a traffic-clogged main street? Better yet, why not do your shopping online and save on petrol and indeed energy? Increasingly in the UK this is proving an attractive option, as major supermarkets Tesco, Sainsbury’s and Waitrose and e-businesses like Ocado and Amazon offer lower prices and a bigger range that any local bricks and mortar store can manage; often with free delivery to boot. Thanks to the latter, nobody much is buying music, books or even computer games from their local any more: iconic chains HMV, GAME and Waterstones are all struggling for their corporate lives. A recent Deloitte report suggests that up to an astonishing 40% of shops on the “high street” could close in the next five years.

The local retail experience has in fact been more dramatic and more pronounced than in Britain; in most Australian metropolitan suburbs there is no “high street” to speak of, at least in the British sense of the term. The domination of the grocery sector by Woolworths and Coles and malls in the American style have reduced many of our main streets to depressing wastelands of “$2 shops”, chain stores, take-aways and struggling restaurants. The only “pop-up” shops (a London trend spruiked optimistically by Wayne Hennessy in the Guardian) that tend to appear in Australia can be described as such because they tend to disappear from the scene just as quickly as they arrive.

So is the “high street” really worth saving through direct local and state government investment, or is it a concept that, in reality, is past its used-by-date? I am certainly sympathetic to the idea of providing some incentive or subsidy to local, independent businesses trying to make a start in the centre of town, but it also feels a bit like government would be a small fry pushing against the tidal wave of the retail market.

It would be particularly interesting to hear of people’s personal experiences with their own local “high street”. Is it alive? Has a local mall taken over? Does it really matter if the malls win?

Please note – this thread’s just for the analysis of media manoeuvres and their intended effects – discussion of other aspects of issues of interest belongs elsewhere. e.g. browse the archives | roundtables | open thread