I think assigning blame is the wrong priority. One can certainly understand the reluctance of dam operators to let go of all that water, particularly shortly after the end of an epic drought that brought the entire region to its knees over the past decade. Mother Nature delivers the punches, and sometimes you just can't make yourself roll with them fast enough:
AN EXPERT hydrologist working for the floods inquiry has confirmed dam releases were a "major component" of January's destructive floods but rejected critics' suggestions that Brisbane and Ipswich could have been saved by earlier dam releases.
Flood hydrologist Mark Babister, of Sydney-based WMA Water, chairman of the National Committee on Water Engineering, said Brisbane might have been saved damage but not Ipswich.
In his 53-page report, Mr Babister is critical of the manual used to control Somerset and Wivenhoe dams.
The document had limitations and did not account for the "natural inclination" of dam operators to withhold dam releases, he wrote. He also noted failures to take weather forecasts into account when making releases.
...During January's flood, dam operators held back releases until January 10, when the equivalent of two North Pine dams was released into the Brisbane River.
..."With the benefit of hindsight, it is clear that an earlier escalation of the dam outflow rate would have reduced the ultimate peak release discharge downstream of Moggill, including at the Brisbane CBD," Mr Babister wrote.
"However it appears that earlier releases could have exacerbated flooding at Ipswich and the lower Lockyer Valley.
..."Incorporation of predicted rainfall into the decision-making process for the manual should be considered."
The consultant agreed with other dam critics who said outdated technology was used by the Queensland Government to make important decisions during the flood.
..."The current suite of forecasting models does not include a functional hydrodynamic model," Mr Babister said.
"Such models have the advantage that they properly account for the interactions that occur at the confluence of major tributaries."
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