Landslides Explained: Causes, Warnings, and Life-Saving Safety Tips

What Is a Landslide?

A landslide is the sudden downward movement of rock, soil, or debris down a slope due to gravity. This movement occurs when the forces holding earth material in place become weaker than the forces pulling it downward. The point where a landslide begins underground is called the focus, while the area directly above it on the surface is the epicenter.

Causes of Landslides

Heavy rainfall and landslides are closely connected, with 76% of landslides occurring due to rainfall. When water saturates the soil, it increases weight and reduces the friction between rock and soil layers, making slopes unstable.

What triggers landslides includes several factors:

• Intense rainfall that saturates soil and increases pore water pressure

• Soil erosion caused by water flow over steep surfaces

• Human activities like construction on steep slopes or cutting into hillsides

• Earthquakes that shake loose unstable materials

• Deforestation that removes tree roots holding soil together

• Poor drainage systems that allow water accumulation

Common Warning Signs of Impending Landslides

Recognizing landslide warning signs can provide crucial time for evacuation. Key indicators include:

• New cracks in the ground, pavements, or building foundations

• Bulging ground at the base of slopes

• Tilting trees, poles, or fences that were previously straight

• Springs or wet areas appearing where the ground was previously dry

• Sudden changes in water flow - either rapid increases or decreases in streams, especially with muddy water

• Unusual sounds like trees cracking or boulders knocking together

• Doors and windows sticking or frames going out of alignment

• Movement of animals toward human settlements, indicating disturbance in hills

Types of Landslides

Landslides are classified based on their movement patterns:

• Falls: Rock or debris falling from cliffs or steep slopes, often creating scree at the base

• Slides: Material moving along a distinct surface, including rotational slides (curved movement) and translational slides (planar movement)

• Flows: Material behaving like liquid, including debris flow that contains rocks, soil, and water moving rapidly downhill

• Topples: Forward rotation of rock or soil masses

• Creep: Very slow downward movement of material over long periods

High-Risk Areas and Conditions

India's landslide prone areas are concentrated in mountainous regions. Recent data shows:

Highest Risk States:

• Sikkim: 57.6% of land area susceptible to landslides

• Uttarakhand: 32% high-risk areas

• Himachal Pradesh: 29% high-risk areas

• Kerala: Highest among non-Himalayan regions

• Arunachal Pradesh: Largest absolute area at risk

The Geological Survey of India currently provides landslide early warning for 21 districts across eight states, including Nilgiris, West Bengal, Sikkim, Kerala, Karnataka, Uttarakhand, Himachal Pradesh, and Nagaland.

How to Prepare for a Landslide?

Landslide preparedness involves both structural and non-structural measures:

Property Protection:

• Avoid building on steep slopes or near mountain edges

• Install flexible pipe fittings for utilities to prevent breakage

• Build retaining walls on steep slopes

• Plant trees and ground cover to hold soil with roots

• Keep drainage systems clean and functional

• Construct channels to divert water flow away from vulnerable areas

Emergency Planning:

• Contact local geological surveys for property assessment

• Develop evacuation routes and identify safe areas

• Prepare emergency supplies including water, food, and first aid kits

• Establish communication plans with family members

What to Do During a Landslide?

When landslide activity begins, immediate action is crucial:

Safety Actions:

• Move away immediately from the landslide path without wasting time

• Stay alert and awake - many fatalities occur when people are sleeping

• Listen for unusual sounds indicating moving debris

• Avoid crossing landslide areas or walking on loose material

• If unable to escape, take shelter behind large rocks or sturdy trees to avoid injury from debris

• Don't return to retrieve belongings - save yourself first

For Drivers:

• Watch for collapsed pavements, mud, fallen rocks, and debris on roads

• Be especially careful near embankments, which are highly susceptible

Post-Landslide Safety Measures

After a landslide event, several precautions are essential:

• Stay away from the slide area - additional slides may occur

• Check for injured persons and provide assistance if safely possible

• Report broken utility lines to authorities immediately

• Watch for flooding downstream from landslides

• Document damage with photographs for insurance claims

• Listen to emergency broadcasts for official instructions and warnings

Tips for Protecting Your Home and Property

Landslide prevention at the property level includes:

• Professional assessment of slope stability before construction

• Proper drainage installation to manage water flow

• Retaining wall construction for steep slopes

• Vegetation planting with deep-rooted plants to stabilize soil

• Insurance coverage evaluation for landslide damage

• Regular inspection of slopes for cracks or instability signs

How Communities Can Reduce Landslide Risk

Community-level landslide safety tips involve coordinated efforts:

Government Initiatives:

• Landslide hazard mapping by GSI covers 4.3 lakh square kilometers across 19 states

• Early warning systems operational in high-risk districts

• Building codes enforcement in vulnerable areas

• Land-use planning to restrict construction in dangerous zones

Community Actions:

• Public awareness programs about warning signs and safety measures

• Regular monitoring of vulnerable slopes

• Emergency response training for residents

• Coordination with authorities for evacuation planning

Recent Data from India

Recent landslide incidents highlight the ongoing threat. The 2024 Wayanad landslides in Kerala became the deadliest in the state's history, killing over 420 people and injuring 397 others. The disaster affected tea plantation workers in Mundakkai and Chooralmala villages, with 578mm of rainfall in 48 hours triggering the catastrophic event.

2024 monsoon season brought widespread landslide activity across India. Himachal Pradesh recorded 31 deaths from flooding and landslides between June and August. The Geological Survey of India conducted 45 detailed investigations of chronic landslides nationwide during 2019-2024.

Understanding landslides and following safety measures can significantly reduce their devastating impact. With proper preparation, early warning recognition, and community cooperation, we can protect lives and minimize property damage from these natural disasters.