Introduction
India’s topographic fragility, intense monsoon precipitation, and tectonic seismicity render approximately 12.6% of its landmass (around 0.42 million sq. km) prone to landslides, according to the Geological Survey of India (GSI). This vulnerability is primarily concentrated in the young fold belts of the Himalayas and the North-Eastern hills, as well as the older escarpments of the Western Ghats.
1. Non-Structural Measures (Planning and Risk Assessment)
- Hazard Zonation Mapping: Prioritising macro- and micro-level Landslide Hazard Zonation (LHZ) mapping at scales such as 1:10,000 to demarcate high-risk areas and regulate developmental activities and human settlements.
- Early Warning Systems (EWS): Deploying rainfall-threshold and sensor-based real-time early warning systems managed by the Geological Survey of India (GSI) as the nodal agency, integrated with meteorological inputs.
- Land-Use Regulation and Building Codes: Enforcing strict hill-slope building bylaws, halting unscientific slope cutting for highways and urban expansion, and preventing construction along designated landslide corridors.
- Capacity Building and Community Preparedness: Training local communities, Panchayati Raj Institutions (PRIs), and Civil Defence personnel as first responders through institutionalised awareness campaigns and regular mock drills.
2. Structural Measures (Engineering and Slope Stabilisation)
- Mechanical Slope Reinforcement: Constructing retaining walls, gabion structures, rock bolting, and soil nailing to physically stabilise toe slopes and arrest rockfalls.
- Bio-Engineering Interventions: Establishing deep-rooted vegetation and hydro-seeding with native species like vetiver grass to bind soil layers, enhance slope cohesion, and reduce superficial erosion.
- Drainage Correction: Designing adequate surface runoff diverters and sub-surface perforated drainage channels to prevent pore-water pressure buildup and rainwater percolation—the primary triggers for slope failure.
Conclusion
Landslide risk management requires a decisive shift from post-disaster response toward risk-informed, anticipatory mitigation. Aligning infrastructure planning with the National Landslide Risk Management Strategy and Priority 1 to 4 of the Sendai Framework will ensure climate-resilient and sustainable mountain development.