About 30 fire and rescue volunteers are fighting a fire east of Lake Clifton started by lightning last night.
The threat has been downgraded as the fire is contained.
Old Bunbury Road is closed from Forrest Highway to Old Coast Road.
The fire, which started in bushland south of Old Bunbury Road, was reported at 11.15am today.
A bushfire alert was issued after 1pm.
By 5.20pm residents were told there was a possible threat to lives and homes, and they needed to leave or get ready to actively defend their properties.
An hour later, volunteers had strengthened containment lines and had the fire under control.
The Department of Fire and Emergency Services reminded residents of Lake Clifton to be aware and keep up to date in case the situation changes.
Are asked to stay alert and monitor surroundings.
Watch for signs of a bushfire, especially smoke and flames.
Close their doors and windows, and turn off evaporative air conditioners but keep water running through the system if possible.
Are asked to exercise caution if they are in the area, to turn their headlights on and drive slowly.
They are asked to watch for emergency services personnel and follow their directions.
If drivers cannot see clearly, they should pull over, keep their headlights and hazard lights on, and wait until the smoke clears.
People with respiratory conditions affected by smoke should contact a doctor or call Health Direct on 1800 022 222.