Kiama mayor Brian Petschler says flood controls put in place during decommissioning works on Jerrara Dam went according to plan during last week's heavy rain.
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It had appeared that Jerrara Dam might actually fail and calamitous news reports of Kiama being swamped were shared in the media around the country on Tuesday.
With planned decommissioning work under way and a large cut being made in the dam wall, the region's State Emergency Service feared for the safety of residents immediately downstream.
About 9.20am on Tuesday the SES made the decision to move from an amber to red alert and evacuate the properties in the dam's shadow.
The SES issued a text message and media alerts stating dam failure was imminent and would result in extremely dangerous flooding of Mt Brandon Road, Jerrara.
Mid-morning on Tuesday reconnaissance was conducted in a Westpac Lifesaver Helicopter. The danger was found to be minimal. The all-clear was eventually given on Wednesday morning.
More than 330 millimetres of rain fell in Kiama last Tuesday and Wednesday causing flooding, road closures, school and preschool closures and damage to houses. The Kiama SES unit answered 66 requests for assistance including six flood rescues.
Decommissioning work on Jerrara Dam began in June and was expected to take up to three months to complete, weather permitting.
Kiama SES unit controller Warren Turner said the decision to issue the evacuation order to houses in the immediate vicinity of the Jerrara Dam was a sound one.
"Council gave us an amber alert initially and with discussion with our region they recommended we go to red alert for the five or six houses downstream of Jerrara Dam," he said.
"The region acted on the up-pendulum-side of being cautious.
"We know the dam has had some work as part of the decommissioning, we know an interim spillway has been put in and we know another wall has been built to protect the riding school [Riding for the Disabled]."
Kiama SES unit deputy controller John Wall said the removal of the dam wall, as part of the decommissioning process, had made the flooding look worse than it was.
"It did look pretty scary at the time and that was part of the reason we went for the red alert.
"As an emergency manager you have to make sure you put people first," he said.
"Sometimes that means inconvenience for people but it's better to be safe than sorry. Even though it is very unlikely that the dam would have breached, there was enough of a chance for us to take the action that we did."
Cr Petschler said measures put in place at the dam site went exactly according to the guidelines set down in the decommissioning process.
"The contractor will now go in and finish the work which when complete will see the water flow like the creek that was originally there before the dam was built.
"It was as a good test," Cr Petschler said.