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Whakatāharahara i te horo whenua

Reduce the risk of landslides

If you know your land is unstable, there are a number of things you can do to prevent slips from occurring.

Get advice from professionals

If you are having any concerns about unstable land, contact a local engineering consultancy for advice. 

Ask for a Professional Engineering Geologist (with PEngGeol registration) or Geotechnical Engineer (with CPEng registration). 

They are trained to recognise signs of serious problems that you might not see – a quick site inspection could save your house. 

Control the flow of water

Many landslides are triggered by excess water flowing over the surface or in the soil. 

Make sure that stormwater from your property does not discharge or overflow towards any unstable land. Check your pipes, irrigation systems or stormwater soakage

If stormwater does flow over the slope, try to direct it away from the least stable areas. Avoid water soaking in by filling the cracks with clay.

Digging drainage swales may control the flow direction but could encourage water to soak in and form a line of weakness. 

If a landslide has occurred, cover bare surfaces and cracks in the ground with tarpaulins to reduce the impact of rain.

Take care – only do this if you can do it safely. Avoid the landslide if it is still raining. 

Reduce the load on the unstable land

If the slip has a heavy load at the top, it is more likely to fail. 

Keep heavy mobile objects such as cars away from the top of unstable slopes. 

Do some planting on the slopes

Plants can be very effective at sucking the excess moisture out of a slope, adding to the stability and reinforcing the slope with their roots.  

What you need to consider when planting

When you're thinking of planting on a slope, remember to:

  • keep yourself safe while carrying out any remediation work
  • choose the right plants
  • control pest plants
  • minimise soil erosion.

Read the planting guide

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