Sensor installation begins at 125 landslide-risk locations in Nilgiris

Installation of modern sensor devices has begun at 125 locations identified as having landslide risk in Nilgiris district, Tamil Nadu. The district’s hazard inventory lists 234 locations as dangerous areas.

Survey and monitoring

The Geological Department prepared a report after surveying the area following landslides during recent heavy rain. Landslides occurred at 65 locations during that spell. Sensor-based monitoring was already being carried out at six locations.

Important Facts for Exams

• Rainfall-related instability: Rainwater infiltration can promote landslide conditions by increasing soil water content, including through loss of suction or saturation.
• Movement types: In landslide classification, falls involve free-falling blocks, topples rotate away from vertical faces, and slides move largely intact over inclined surfaces or shear zones.
• Shallow failures: A landslide is classed as shallow when its sliding surface lies within soil or weathered bedrock, typically from a few decimetres to several metres deep.