AS community consultation continues on the possible decommission of Jerrara Dam, some have questioned whether the dam needs to be touched at all.
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Jerrara dairy farmer Greg Harris said the current alert system worked well and argued that improvements to the dam would be a waste of money.
"On a slow news day in heavy rain and the red alert for Jerrara dam is broadcast, the Sydney helicopters hover over [it] relaying stories about Jerrara Dam about to bust, but the residents are nearly killing themselves with laughter," he said.
"I went down [during a red alert] to look and thought the dam must be cracking, but the waters were still a metre and a half below the wall of the dam."
He said the council's proposal to decommission the dam by digging a 27-metre channel through the dam wall, dropping the water level to two metres and allowing water to run naturally, could lead to more frequent flooding of the Mt Brandon Road causeway.
"[Currently] when you get the heavy rain, the dam fills up before the crossing goes over," he said.
"Has the cost of building a bridge been added into the decommissioning costs so residents can safely get out of Mt Brandon Road?"
Fellow resident Neil Hawkins agreed a better bridge was needed.
"You would lose the control over how much water you let out," he said.
Mr Harris said the measure could be detrimental for dairy farmers using Terragong Swamp.
"As it is now, it's running all the time, but if it's running naturally, most of that water's gone then when it does get dry, there'll be no water running down from Jerrara Dam," he said.
"It's a joke really - the best option is to build [the dam wall] up, but I can't see them doing that money-wise.
NSW Dams Safety Committee executive engineer Steve Knight said residents should take the risk seriously.
He said as a small catchment, Jerrara Dam had the capacity to rise from near-empty to spilling in a matter of hours.
In 2007, the Dams Safety Committee determined there was significant risk to life, the environment and property in the event of a dam failure..
The design flood has a 1 in 100,000 chance of occurring every year and studies showed Jerrara Dam would fail if it ever occurred.
Kiama Municipal Council acting general manager Bryan Whittaker said while the modelling parameters were high, public safety was paramount.
"The design storm events used for the modelling are established by the Dams Safety Committee and used across the state for all prescribed dams," he said.
Mr Whittaker said the council was aware the Mt Brandon Road causeway was subject to overtopping and its replacement had been identified in future capital works programs.
Full studies and concept plans are on public exhibition for residents to have their say. Submissions close on October 1.