Brisbane flood was the work of a negligent bureaucracy

Had Brisbane's big flood-mitigation dam been operated with any semblance of thought, the flood would not have happened. And they ignored those who were thinking

A pioneer of the Brisbane Valley was asked to "call back tomorrow" when he made an urgent Sunday morning call to the Wivenhoe Dam's operator, SEQWater, to seek immediate action to mitigate a large flood he warned would soon occur from rainfall across the catchment.

Chris McConnel - whose family's history in recording and forecasting local flooding and rainfall goes back to the 1840s, when his great-grandfather settled the land - said yesterday he was "very angry" his warnings were not heeded by SEQWater on the crucial January weekend.

Mr McConnel wants the royal commission-style inquiry into the floods to examine the duty roster on the weekend of January 8 and 9 to establish the seniority and availability of staff making vital decisions on water releases as the dam filled with increasing inflows and rainfall.

He said that if asked to give evidence at the inquiry he would explain that at about 11am on Sunday, January 9, after measuring the river height and talking to local contacts about rainfall in their gauges, he rang SEQWater to warn of an imminent and "very large flood".

Mr McConnel said he knew then that it was imperative for the dam operator to immediately and significantly increase its rates of release of water to give the dam critical storage for floodwater. But he said after explaining the situation to SEQWater he was put on hold and then told he should "call back tomorrow" on the same 1800 telephone number to speak to the right people. "I said to him: 'That's going to be too bloody late. We're going to get a big flood and the dam needs to be releasing a lot more water to cope'," Mr McConnel told The Australian yesterday.

"The SEQWater guy said to me, 'Well, I can't add to what I've said. Please ring back tomorrow'."

Mr McConnel, a grazier who runs a heritage-listed property that has been in his family for 170 years, said he spoke to his local newspaper, the Brisbane Valley Sun, "to ensure this is not swept under the carpet".

Mr McConnel said that during previous floods he and other locals with extensive knowledge of conditions in the catchment area and its local creeks had found it impossible to reach the right people at SEQWater on weekends and public holidays to give them a warning. "Nature does not stop on weekends, and it doesn't adhere to an operating manual for a dam," Mr McConnel said. "I am very angry at the management of the dam and the operating manual. What has happened is just crazy."

SEQWater has strongly defended its operation of Wivenhoe Dam. But senior engineers and water experts have run calculations showing the flood in the Brisbane River would have been largely avoided if more water had been released sooner.

SEQWater is refusing to provide briefings or answer questions pending the public inquiry headed by Supreme Court judge Cate Holmes.

SEQWater emails leaked to The Australian show that on the morning of Friday, January 7, SEQWater knew from the Bureau of Meteorology to "expect heavy rainfall from Sunday to Tuesday".

The emails show that the strategy on Friday morning was to start releasing water from the dam's flood storage compartment at 3pm that day at a rate of 1200 cubic metres per second (cumecs) and to stay at that "for a couple of days and continue releasing until the end of the week". The next email on Saturday night, from an SEQWater engineering officer in contact with the flood operations centre in Brisbane, states: "Current releases from Wivenhoe Dam are 1250 cumecs. Forecast for the next four days is for significant rainfall across (southeast Queensland)."

The next email, which was sent about 24 hours later on Sunday night, states: "Current releases from Wivenhoe Dam are 1400 cumecs. However, please note that we are experiencing major flooding in our catchments. Inflows are approximately 5000 cumecs in the upper Brisbane River and 3000 cumecs in the Stanley River system, with rainfall continuing.

"The (bureau's) current severe weather warning predicts heavy rainfall until Tuesday. If these totals eventuate in the next 12 to 24 hours, higher releases from Wivenhoe Dam will be necessary."

By 6.50am on Tuesday - after heavy rain in the preceding 36 hours - the next email states: "We are entering conditions where dam safety overrides other concerns, although minimisation of urban flooding remains very important."

Senior engineers said SEQWater's strategy of making relatively small releases led to the dam's flood compartment almost filling up, and forced the operator to make huge releases late on Tuesday which led to most of the flooding in the Brisbane River.

Mr McConnel said many residents agreed dam policy and management were responsible for most of the flooding.


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