Landslides

If you think a landslide is about to happen, call NSW Police on 000. They are the lead agency for landslide emergencies.

Let neighbours around you know and evacuate to a safer location.

What is a landslide?

A landslide involves the break-up and downhill flow of rock, mud, water and anything caught in its path. 

Landslides can be triggered by:

  • Floods.
  • Saturation from rainfall.
  • Vibrations from earthquakes.
  • Removal of vegetation.
  • Interference with drainage or construction works. 

Areas prone to landslides

Places that are generally more prone to landslides include:

  • Existing or old landslide areas.
  • Areas at or on the top or base of slopes.
  • Within or at the base of minor drainage hollows.
  • Any sloping ground in an area known to have a landslide problem.
  • Drainage gullies.

Conditions to look out for 

The following signs may indicate potential landslide activity. Please be aware that landslides can still happen without any of these indicators.

  • Saturated ground or seeps in areas that are not typically wet.
  • New cracks and scarps or unusual bulges in the ground, roads or pavements.
  • Noise from earth moving or snapping tree roots.
  • Movement of structures such as decks and patios.
  • Sticking doors and windows, and visible open spaces indicating jambs and frames out of plumb.
  • Tilting or cracking of concrete floors and foundations.
  • Broken water lines and other underground utilities.
  • Leaning telephone poles, trees, retaining walls or fences.
  • Offset fence lines.
  • Sunken or displaced road surfaces.
  • Rapid increase in creek water levels, possibly accompanied by increased turbidity (soil content).

How can I avoid or minimise the impact of landslides?

  • Request information and assistance from Council prior to land purchase or construction. This information could include, amongst other things, past landslide activity and any known landslide risk assessments.
  • Consult a geotechnical engineer or engineering geologist for advice
  • Do not undercut steep banks, develop near the top or base of steep slopes, or place fill on steep slopes
  • Do not stand or seek cover below or near coastal cliffs or overhangs and be aware of potential dangers they represent. Take notice of signs giving warning of loose rocks and debris.
  • Do not spend time in steeper drainage gullies or creeks during significant rainfall.
  • Ensure your roof and stormwater is connected to an appropriate stormwater system.
  • Learn more about the geological hazards in your area and become familiar with tell-tale signs of ground movement.

For further information on :Landslide Risk Management (2007) visit the Australian Geomechanics Society website

2022 Flood Landslides

The unprecedented flooding event of 28 February 2022 turned roads into rivers around the Byron Shire.

The hinterland area west of Mullumbimby township including Main Arm, Wilson’s Creek, Upper Cooper’s Creek, Palmwoods, Wanganui, Huonbrook and the Huonbrook Valley experienced:

  • At least seven significant landslides (and still counting)
  • Numerous small to minor landslides
  • Numerous washouts, where the road has been washed out from below the road.

Landslide locations

  • Huonbrook Road – three significant landslides, two medium landslides.
  • Wanganui Road – two significant landslides.
  • Upper Wilson’s Creek – one significant landslide.
  • Federal Drive  – one significant landslide.
  • Coopers Creek  – one small landslide on low side of road.

Road washout locations

  • Upper Main Arm
  • Palmwoods
  • Main Arm (Williams Bridge abutment washout)
  • Wilsons Creek
  • Huonbrook
  • Upper Wilsons Valley.

For up to date information about current landslips visit Roads impacted by flood

When does Council get involved in landslides and landslips?

We get involved in a landslide incident if it occurs on and involves any potential impact or damage to Council property, assets or infrastructure, such as roads, stormwater, water or wastewater pipes.

We may be called to inspect emergency landslides, and provide geotechnical and engineering guidance to emergency agencies. We would also be involved in clearing a landslide or slip after an emergency, such as the 2022 floods, to restore access via roads to isolated communities.

Landslides and landslips on private property

It is the responsibility of individuals to ensure their homes are not at risk of landslides and resolve any issues created by landslides on their property.

Council can advise of the areas that are most likely to be affected by ground movement. However, only a qualified geotechnical engineering consultant can provide a landowner with detailed advice about their site.

If you’d like more information on the geographical stability of your home, please contact a geotechnical engineering company or your insurer for advice.