In 2006, I spent a couple of days in the Lockyer Valley watching water birds at little lakes just outside the U of Q campus at Gatton. That's just about ground-zero for this flood. I wonder how those lakes fared? Are the birds OK? And the crops in the area? Where will Brisbane get its fresh produce now? And, as always, are the people OK?:
The rainfall record for Helidon had been set in the 1974 floods. On Tuesday the water gauge in the local creek soared past that record, with a reading of 5.2m before it was washed away.
In nearby Gatton, the record water flow in Lockyer Creek used to be 16.33m, set back in 1893. It surged to 18.92m on Tuesday before the creek gauge also stopped, swept away by the forces it was designed to measure.
"They were the stats that really stand out to me from the week," bureau hydrologist Jimmy Stewart said.
...The crazy rain readings mesmerised people whose lives would now be shaped by them.
At 10am on Tuesday, Cr Newman had his "holy heck" moment when he was sitting in a Local Disaster Management Group meeting in Ann St, Brisbane, and the gathering became spellbound by the sight of a storm of biblical proportions on their screen.
"That was a defining moment, when we realised it was a real flood and it was coming," Cr Newman said.
He retired briefly to his office late on Tuesday and called up rain readings on his computer.
A figure of 250mm left him stunned and facing the harsh reality that the toughest days of his life were ahead of him.
"For me, that moment when I looked at the reading, it was the incredible feeling of a burden on my shoulders," Cr Newman said.
"This is happening and I am going to deal with it."
Premier Anna Bligh called Brisbane a post-war zone and Cr Newman could not argue as he sent the type of "blow up the bridge" messages he might have once seen as a boy watching Hogan's Heroes.
When Brisbane's Riverwalk started to disintegrate and float out to Moreton Bay, he gave permission to "destroy" the bridge. The plan was aborted because it was considered too dangerous.
Riverwalk, built at a cost of $17 million, and supposed to last 30 years, lasted only a decade before becoming a glorified crab pot.
With intense rain being recorded across catchments from Brisbane to the Darling Downs, after consulting bureau hydrologists SEQ Water Grid managers decided to lift releases from Wivenhoe Dam to 240,000ML about midnight on Tuesday.
It was a terrible juggling act as managers balanced weather predictions, the effect of tides, further rain, run-off and flooded downstream catchments. By that point every dam in the southeast was spilling water.
But it could have been worse. While that was happening, grid managers were drawing up plans to cope with an utterly horrendous 6.5m flood far worse than the current mark and the possibility of an even greater catastrophe. It was a close thing.
"If Wivenhoe Dam had got another 600mm of water it would have gone through the secondary spillway, which operates automatically," Cr Newman said.
"If that had happened it would have been a flood of a much greater height. A couple of hours more rain and it could have been much more dire."
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