Landslides can injure people and animals and damage property, as well as interfere with supplies and isolate communities. The largest recorded event in the Cairns region is the 1951 Ellis Beach debris flows, which buried 10k of the Captain Cook Highway. Many smaller landslides have occurred around the region since records began in the late 1870s.
What causes landslides?
Landslides can be caused by earthquakes or volcanic activity, but in Queensland, they’re generally caused by heavy rain. The rain saturates the soil on a hillside—often where there has been human activity (eg construction where trees and plants have been removed), past the point where any remaining vegetation can support the soil’s weight against the force of gravity. The top saturated layer of soil then slips down the hill—taking whatever is on the land with it.
Movement of landslide material can vary from abrupt collapses to slow, gradual slides and at rates ranging from almost undetectable to extremely rapid. Sudden, rapid events are the most dangerous because of lack of warning and the speed at which material can travel as well, as the force of its impact.
What will happen?
You may notice changes in the yard or house such as:
- Leaning trees, slumping earth, movement in fences or trees, cracks in paths
- Outside walls start to pull away from the building, new cracks appear in plaster, tile, brick or foundations, doors or windows stick for the first time.
- You may hear a rumbling sound which increase as the landslip nears. A trickle of falling mud or debris may precede a larger slip.
Emergency services may have little or no warning of a landslide.
What should I do?
- Be aware of the area you live in- is it close to a hillslope, cliffs or steep rocky area? Is there a history of landslides?
- If there has been a period of heavy rain, you may be at risk of a landslide. Make sure your household emergency plan includes this hazard.
- If it is safe to do so, leave the area and go quickly to your agreed safer place. Advise neighbours and emergency services of the slip threat.
- If you cannot leave, move to a second storey if there is one. Otherwise curl into a tight ball and protect your head.
- Follow any instructions from emergency services.
After a landslip
- Be alert for emergency information or instructions
- Stay away from the slip area - there may be danger of additional slips.
- Watch for flooding, which may occur after a landslide, or debris flow.
- Check for injured and trapped people near the slip, without entering the slip area.
- Look for and report broken utility lines, damaged roads etc.
- Seek help from emergency authorities if needed.