Mudslides: What causes them and what to do when you encounter one

Mudslides can occur when large amounts of water accumulate and inundate the soil on steep slopes, loosening the top layers. ST PHOTO: KEVIN LIM

What causes mudslides?

Mudslides can occur following heavy rainfall, which causes large amounts of water to accumulate and inundate the soil on steep slopes, loosening the top layers.

Areas with sparse vegetation, often caused by human activities or wildfires, are particularly prone to mudslides.

The roots of plants help to hold the soil together and promote surface run-off, with water flowing down the slope instead of seeping into the soil.

A lack of sufficient greenery means that rain falls directly on the soil itself.

Climate change increases the frequency and volume of rainfall, leading to more flash floods that can cause mudslides.

How do I avoid mudslides?

Hikers and parkgoers should stay on marked trails and check the weather forecast for heavy rain.

They should also be careful when walking near slopes that are bare or where construction worksites are located as mudslides are more likely to occur there. Look out for trickles of flowing mud, which may signal that a mudslide is developing.

What should I do if I encounter a mudslide?

Stay away from the site and move to safety. Flooding or a larger mudslide can occur after the initial incident.

If you spot any injured or trapped persons as a result of the mudslide, check on them only if you can do so without entering the site of the mudslide.

How safe is it to visit the Bukit Batok quarry area?

As the section of the park affected by the slope failure incidents is not accessible to the public, the park is still safe for visitors, said the National Parks Board (NParks). Access to the observation area at the quarry remains open as the cliff is not linked to the observation area.

What is being done to address the mudslides?

Other than the slope failure incidents at the quarry, there were another two slope failure incidents between the quarry and Shelter E that had occurred in late August, said NParks. The footpath between the quarry and Shelter E has since been closed for stabilisation works.

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