The bushfire is about 7000sq m in size and burning north of Sanctuary Point, south of The Wool Rd and to the west and east of Larmer Ave.
The flames are yet to be contained, fire crews said.
Residents in Sanctuary Point, Old Erowal Bay and Erowal Bay have been told to “prepare now” as conditions worsen in the South Coast.
A watch and act warning is also in place for residents in Glen Alice as crews work to contain a bushfire burning in remote areas to the west of Glen Alice.
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