Use of dam manual 'not priority'

A SENIOR Queensland water official has admitted Wivenhoe Dam's manual was "not a priority for operating in the field".

A SENIOR Queensland water official has admitted Wivenhoe Dam's manual was "not a priority for operating in the field" and he was unconcerned by the legal ramifications of breaching the guidelines.

The admissions by SEQWater dam operations manager Rob Drury came during heated testimony before the state's flood inquiry, where an independent dams expert also wavered in his long-held view that Wivenhoe flood engineers acted by the book.

Commissioner Cate Holmes has reconvened hearings to examine the credibility of SEQWater's official report on the Brisbane flood after The Australian exposed a string of inconsistencies in the engineers' evidence suggesting they disregarded the manual and used the wrong flood mitigation strategy in the days before the city was swamped.

The engineers have asked Justice Holmes to trust their March report, which counsel assisting Peter Callaghan SC alleges is "a fiction" concocted to demonstrate the engineers engaged each strategy as required.

Wivenhoe's manual requires operators to assume one of four release strategies during a flood, ranging from minor releases that preserve rural bridges, known as W1, to heavy outflows to keep the dam wall intact, known as W4.

In the witness box yesterday, Mr Drury could not offer any explanation for an email he sent to SEQWater Grid Manager operations director Daniel Spiller on January 10 last year at 8.23am, stating explicitly that the dam was operating under the transitional strategy W2, contradicting SEQWater's claim that W2 was bypassed for W3 on January 8.

Barrister Jim Murdoch SC, for mid-Brisbane River irrigators, asked: "As a senior professional, if you were wrong on that, it's a humiliating error, isn't it?"

Mr Drury replied: "The W strategies were a priority for operating in the field. Me saying the wrong W strategy was purely off the top of my head, me saying what I thought at the time. The strategies, the releases, the (situation reports) were all the important things. There certainly wasn't comment on W strategies though, because they were not at the time a priority nor a necessity."

Mr Spiller, who entered the witness box late yesterday, said he used the information in Mr Drury's email to inform Natural Resources Minister Stephen Robertson and other key stakeholders about the status of the dam.

Asked by counsel assisting Elizabeth Wilson SC if Mr Drury was aware the information would be passed on to the highest levels of government, Mr Spiller replied: "Absolutely."

Also appearing yesterday, independent dams expert Leonard McDonald cast doubts on the findings of a report he completed in March that found dam operators followed the manual. Mr McDonald was taken to evidence he did not examine at the time, including a situation report dated 5.53pm on January 9 stating "the event magnitude will require the application of Wivenhoe Dam flood operation strategy W2".

Mr McDonald said the situation report "would suggest to me that the current strategy was W1".

Barrister Darryl Rangiah SC, for Fernvale residents, asked: "If in fact the W1 strategy was engaged at this time, it would be a breach of the manual, wouldn't it?"

The witness agreed.

The inquiry will resume this morning.