Four US engineers testify in today’s hearing into Paradise
US DAM expert Paul Rizzo will be among the five witnesses who will discuss what is wrong with Paradise Dam in today’s hearing in Brisbane.
Dr Rizzo is compiling a review of Sunwater’s technical reports of the dam on behalf of Bundaberg Fruit and Vegetable Growers, but some of the authors of the reports he scrutinises will also testify.
This includes US concrete materials engineer Steve Tatro, from TatroHinds, and GHD principal dams engineer James Willey, who already spoke during last week’s hearings in Bundaberg about a high ratio of unbonded lift joints at the site.
Dr Rizzo said in a letter to BFVG’s legal representation that he considered data from TatroHinds’ report to be misleading.
“It is clear that the existing test data set is inadequate to make major decisions regarding the evaluation and possible remediation of Paradise Dam,” he said.
“A new project specific test program is strongly recommended to allow for proper engineering analysis, decision making and cost analysis.
“Consequently, we recommend a new program of sampling and testing, consisting of four parts.”
The letter has been formally tabled as part of the Commission of Inquiry, and Dr Rizzo is expected to further testify by video or by phone today.
Ernest Schrader will also be part of the discussion, and in person.
Dr Schrader was an advisor during the dam’s construction but also had created an index that measured the strength of lift joints.
Yesterday the Commission of Inquiry's senior counsel member Jonathon Horton said he would explore the issue of the dam’s measured Factor of Safety with witnesses within the next few days.
He said this after commissioners, John Byrne and John Carter, stated that they intended to determine if the dam’s FOS was one or higher.
A local academic recently described FOS as a critical measurement for structures, and a value of one or higher would mean the dam could withstand more than 100 per cent of the load applied to it.
Justice Byrne noted that during hearings there had been emphasis on whether the dam’s construction complied with the Australian National Committee on Large Dams 2013 guidelines, but he said the Commission had to instead focus on the dam’s stability.
After the hearing, Commissioner John Byrne said bringing the witnesses together would allow the inquiry to explore important issues while determining different points of view between them.
“For the Commission and those following the inquiry’s progress, it’s a good opportunity to hear expert witnesses testifying about the same questions simultaneously,” Justice Byrne said.