From the outset they had questions, which demanded answers, and if the loudest members of the crowd were any gauge, they left disappointed.
Michael Reeves from Sydney-based WMAwater explained the science and the methodology behind his conclusions, which put parts of Mulwala at risk of flooding in the event of a 1%AEP flood.
Often called a 1-in-100-year flood, this represents a one per cent chance that a flood of a certain magnitude will be reached or exceeded in any given year.
He said draining the lake and opening the gates before a 1%AEP flood reached Lake Mulwala would only delay the inevitable but not impact the flood peak.
But with no living memory of Mulwala ever flooding, majority in the crowd appeared unwilling to accept WMAwater’s conclusions.
The only Federation councillor in attendance was Mulwala-based, Cr Andrew Kennedy.
He said it was good to see the meeting so well attended as it was a big issue for the town.
Cr Kennedy said the council had no option but to accept WMAwater’s findings.
“I’m no scientist but two different groups have come up with the same results,” he said.
“I don’t think Mulwala is ever going to flood, but it could happen, it is possible and that’s the thing.
“We’ve been forced to do this study by the State Government, and eventually every council on the river will have to do the same.”
The emotion in the room last Wednesday was palpable as council sought community input into potential mitigation measures.
Easily the dominant issue was the skyrocketing cost of insurance.
Cr Kennedy, who is also a builder, said it was possible to get around the building heights, but insurance was the big problem for most residents.
“You can put houses on stumps like in Queensland,” he said.
“That’s an extra cost, but you can get around it.
“The problem now is that the insurance companies have got hold of it.”
One gentleman reported his insurance renewal quote rose from $4,000 per year to $58,000 after the flood study was released, and others expressed fears for their children and grandchildren not being able to buy their own home.
Council’s Director of Planning, Place and Sustainability, Susan Appleyard told the crowd that the council was not responsible for insurance costs but that they could lobby the Insurance Council of Australia to go back to the current levels in the Local Environmental Plan (LEP).
“I’m not sure how much success we would have, but that is one thing we can do,” she said.
“The other thing I’m hearing tonight is that people are looking for more dams to control the flow of water … more gates on the weir, and more management in the upper reaches of the catchment.”
The Hume Dam was built to maximise irritation storage and flood mitigation is a secondary consideration, but Ms Appleyard said there had been a lot of lobbying over the decades to have flood mitigation boosted “without a lot of joy”.
“Council staff and councillors have met with Murray Darling Basin Authority regarding the new plan, and this is one of the key issues that we have discussed,” she said.
“They need better flood control, or they need to prioritize flood control through that system.”
Council’s project manager, Trevor Cook said nothing was off the table.
“The (flood study) is about understanding the flood risks and the impacts, what buildings are impacted, what roads are impacted, to what depth, to what extent that risk occurs, then we're identifying a range of different risk mitigation measures,” Mr Cook said.
“But also looking at the overland flow and what we can do there ... can we improve the drainage to reduce ponding some of these areas?
“We want to get the full range of measures, and then we assess them in terms of how good they are at reducing risk, while also considering economic, environmental and social impacts.
“Talking about building a levy - a levy would work, but it may not be socially acceptable having a levy on the foreshore.
“We try and look at all of the options; a prioritized list of options that will be Council's strategy for managing flood risk into the future; that would be their blueprint.”