According to the National Disaster Management Authority, a landslide is defined as the downward and outward movement of slope-forming materials, including rock, soil, artificial fill, or a combination of these, under the influence of gravity. The Geological Survey of India, the country's nodal agency for landslide studies, further classifies landslides into falls, topples, slides, spreads, and flows based on the movement of material.
Data compiled under the Geological Survey of India's National Landslide Susceptibility Mapping programme shows that nearly 13.17 to 15 percent of India's geographical area, covering approximately 4.2 lakh square kilometres, is officially identified as landslide-prone. The causes of landslides vary across different regions, prompting the Government of India to classify vulnerable areas into distinct geographical hotspots based on their natural characteristics.
The Himalayan region remains one of the most vulnerable zones because it is the world's youngest, highest, and most tectonically active mountain range. Its fragile geology consists of fractured, crushed, and unstable rocks that are continually weakened by earthquakes and seismic activity. At higher elevations, rising temperatures can also trigger glacial lake outburst floods, releasing enormous volumes of water and debris that surge through mountain valleys and intensify landslide risks.
India's Northeastern hill ranges are also highly susceptible to frequent and severe landslides. States such as Mizoram and Arunachal Pradesh have historically recorded some of the highest numbers of such incidents. The region's steep terrain, composed largely of sedimentary rocks that erode easily, becomes increasingly unstable during periods of heavy rainfall. Continuous precipitation saturates the slopes, causing weakened rock layers to collapse.
The Western Ghats and the Nilgiri Hills face a different pattern of landslide activity. Stretching across Kerala, Karnataka, Goa, and Maharashtra, the region is covered by thick layers of soil rather than exposed rock. During intense monsoon rainfall, the soil absorbs vast quantities of water until it becomes saturated and unstable. The resulting heavy mud mass eventually exceeds the supporting capacity of the underlying bedrock, causing destructive downhill flows.
Dr. Vipin Kumar, Assistant Professor and Head of the Department of Geology at Doon University in Dehradun, identified India's three major landslide hotspots as the Northwest Himalaya, covering Kashmir, Himachal Pradesh, and Uttarakhand; the Northeast Himalaya, primarily Arunachal Pradesh along with the Arakan Range in Nagaland and Manipur; and the Western Ghats, particularly Kerala. He stated that landslide incidents rise sharply during the arrival of the southwest monsoon in June and July, leading to significant casualties and widespread damage to infrastructure.
Experts identify the southwest monsoon, which generally extends from June to September, as the single biggest trigger for landslides across India. During this period, hilly regions receive exceptionally high volumes of rainfall within short intervals. Climate change has further intensified these conditions by producing highly concentrated rainfall events and violent cloudbursts, with rainfall that would normally fall over several days sometimes occurring within just a few hours. The rapid influx of water saturates the soil, increases internal pressure, separates soil particles, and ultimately destabilises mountain slopes.
Explaining the natural process, Dr. Kumar said that when heavy rainfall saturates the soil, slopes inevitably collapse. He noted that such geomorphological processes occur naturally across the world, including in developed countries such as the United States, Switzerland, France, and Italy. According to him, while landslides themselves are natural phenomena, the scale of destruction is determined largely by the extent of human presence in vulnerable areas.
Kerala-based environmentalist Veena Murathoor stressed that development strategies must be tailored to local environmental conditions. She said construction methods that succeed in northern India cannot be applied without modification in Kerala because the state's climate is significantly different. She pointed out that rainfall in landslide-prone areas often reaches between 600 and 700 millimetres in a single day, while some locations have recorded approximately 221 millimetres within just 24 hours. She emphasised that every development project must be designed according to the landscape and ecological characteristics of the region.
While natural conditions create the potential for landslides, experts say human activities frequently increase both the likelihood and severity of disasters. The National Disaster Management Authority identifies several contributing factors, including unscientific toe cutting, in which road construction and widening projects remove the base of hills, reducing their stability. Agricultural practices, crop selection, and poorly designed drainage systems in hill towns can also weaken slopes by allowing excessive water accumulation, transforming stable ground into unstable terrain vulnerable to collapse.
Dr. Kumar said that although landslides have occurred throughout geological history, fatalities have increased significantly over the past decade because of rapid changes in land use and land cover. He explained that cutting mountains to construct highways often creates steep slopes of 40 to 50 degrees. When these exposed rock faces are subjected to extreme rainfall, their shear strength declines, causing large-scale failures.
To strengthen disaster preparedness, the Government has introduced district-level landslide early warning systems and expanded hazard mapping efforts. The Geological Survey of India has established the National Landslide Forecasting Centre, which issues regional landslide forecasts for high-risk districts whenever heavy rainfall is anticipated. Authorities have also introduced the Bhooskhalan mobile application and the Bhusanket portal, providing real-time landslide bulletins, hazard zoning maps, and incident reports for citizens and experts.
Despite these initiatives, experts believe important gaps remain. Dr. Kumar stated that existing systems such as the Bhukosh portal provide susceptibility maps showing where landslides are likely to occur but do not accurately predict when they will happen. He argued that identifying the timing of potential landslides is essential for protecting lives and critical infrastructure.
JUST IN: Terrifying CCTV footage shows a massive landslide striking a tunnel construction site near Meppady, Wayanad district, Kerala, India.
— Weather Monitor (@WeatherMonitors) July 7, 2026
Three people are reported dead, while six have been rescued. Multiple others are feared trapped as rescue operations continue. pic.twitter.com/Zi76gxfwSX
Referring to international examples, Dr. Kumar said countries including Japan and Switzerland have developed advanced early warning systems that alert residents before landslides occur, significantly reducing human and economic losses.
Experts also recommend greater reliance on predictive research, detailed hazard mapping, and comprehensive land use and land cover studies before approving development projects in ecologically sensitive regions. Such measures, they believe, can improve understanding of landslide risks and prevent cascading disasters.
Veena Murathoor emphasised that understanding the ecology, hydrology, and geology of every location is essential before any construction activity begins. She warned that these environmental factors are often overlooked, resulting in repeated development practices that increase the likelihood of future disasters.
As Wayanad confronts another landslide during the monsoon season, experts maintain that while development cannot be halted entirely, it must be guided by scientific assessment, local ecological understanding, and effective early warning technologies. They believe that combining responsible infrastructure planning with predictive monitoring systems offers the most sustainable path for protecting both communities and fragile natural ecosystems.
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