Friday, 31 March 2017
Clarence Valley Council, media release, March 31, 2017:
Slippage risk in Yamba hill
HEAVY rain in Yamba over the past two days has resulted in the reinstatement of a red alert warning for possible land slippage.
Clarence Valley Council works and civil director, Troy Anderson, said the red alert would remain in place throughout April.
Mr Anderson said Council monitored rainfall at Yamba hill area as it provided a guide to the risk of landslip.
“Once again, the rain that has been experienced has reached the level requiring a red alert to be notified,” he said.
On March 18, council advised red alert level had been reached because of heavy rainfall at that time and reduced to threat level to orange on March 22.
“The situation can change within a day, especially when high rainfall events are experienced,” Mr Anderson said.
“It can take some time for the alert level to be reduced, but this also varies depending on how much rain has fallen in the previous days and weeks.
“With the extra rain that occurred this week, the red alert level will remain in place throughout April. This will continue to be monitored and council will advise of any changes.
“If the area gets another 50mm of daily rainfall owners/site managers/occupants should monitor their land and/or buildings for evidence of any movement during and after this rainfall event.
“Should evidence of any movement be detected, those people should consider evacuation, and immediately advise council of their action.”
Below is a chart indicating trigger levels for the Yamba landslide risk zones.
The shaded area shows the Yamba landslip zone