Landslide and Earthquake

Earthquakes

People in Australia are surprised to learn that hundreds of earthquakes occur below our feet every year. The majority are too small to feel, let alone cause any damage. Despite this, we are not immune to large earthquakes. Australia records at least one magnitude 5 earthquake every year and a magnitude 6 approximately every ten years.

There is no accepted method to predict an earthquake so it’s vital to know what to do during an earthquake as you will not receive any warning. How you should react in an earthquake depends on where you are at the time.

Earthquakes can trigger secondary events such as landslides, tsunamis and fires caused by downed power lines and ruptured gas mains.

Have you got an earthquake plan?

Map of earthquakes in NSW

Landslides

Every year in Australia landslides damage many houses and cause millions of dollars damage to buildings, roads, railways, pipelines, agricultural land and crops with some causing injuries and loss of life.

Landslides involve the movement of large amounts of earth, rock, sand or mud, or any combination of these. Landslides can be sudden and fast moving, moving millions of tonnes of debris. They can travel distances spanning only a few centimetres, to many kilometres when large mud flows follow river valleys.

Landslides can be caused by a major event such as earthquake, but in NSW, landslides are generally caused when heavy rain saturates soil on a hillside past the point where 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.

Although major landslides in NSW are uncommon, it pays to know if you are in a high risk area. Contact your local council prior to any land purchase or construction. The information they can provide includes, amongst other things, past landslide activity and any known landslide risk assessments.

Landslide Get Ready

Thredbo Landslide Disaster Case Study