The South Australian SES has issued a flood emergency warning for the Adelaide Hills town of Echunga due to a nearby dam wall that has a “high risk” of collapsing.

State Emergency Crews worked overnight to mitigate the flooding threat after being alerted to a failing dam 500 metres upstream of Echunga on Tuesday.

The privately-owned dam is up a hill near Marianna Street. The SES initially issued a “watch and act” message for Echunga on Tuesday night but upgraded that to a flood emergency warning at 5.25am on Wednesday.

The warning zone in the SA town of Echunga. Image: SA SES

“Due to the high risk of the wall collapsing, SA SES are working with partner agencies to lower the level of the dam through the excavation of a spillway,” the SES said in a statement.

“This has the potential to release water which may exceed the capacity of the drainage system of Echunga, which may cause parts of Echunga to flood.”

The SES has asked residents in the warning area to consider evacuating to the Echunga Football Club or a house outside the potential flooding area.

SES state duty officer Dave O’Shannessy said about 60 homes could be affected if the dam failed.

“It’s most of that central township of Echunga, we believe it’s around 60 homes and properties,” Mr O’Shannessy told ABC Radio this morning.

“We’re just in the process of working with the community to work out how many people are there and how many people need to leave.”

Several roads around the township have been closed, including Aldgate-Strathalbyn Road at Echunga Road, Echunga Road at Aldgate-Strathalbyn Road, Battunga Road at Meadows Road, Strathalbyn at Sophia Street and Churchill Road at Old Mount Barker Road.

Mr O’Shannessy said the Department of Environment and Water estimated the dam held about 10 megalitres of water.

“I don’t think it is inevitable that it will fail,” he said.

“What we’ve seen overnight is from our response approximately four o’clock yesterday until now is there has been a deterioration in the wall’s integrity of that dam.

“However, we’re doing everything we can to mitigate that risk, we’re doing controlled releases of water, we’ve got engineers involved, we’ve got other experts involved.

“So no, I don’t think it’s inevitable. However, we’re just asking the members of the public in Echunga and surrounds just to consider their own safety and perhaps leaving the area just in case that were to happen.”

• This story first appeared in InDaily and is republished here with permission