Kerala hit by monsoon landslides | Explained
The story so far: Catastrophic landslides have become a recurring monsoonal phenomenon in Kerala, nestled in the foothills of the Western Ghats along India’s west
The story so far: Catastrophic landslides have become a recurring monsoonal phenomenon in Kerala, nestled in the foothills of the Western Ghats along India’s west coast. Every year, landslides claim scores of lives in the State, which has a high population density and extensive habitation across vulnerable terrain. This year, the first major incident was reported in Wayanad, where a debris slide triggered by an extreme rainfall event at the entrance of the under-construction twin tunnel at Kalladi in July claimed eight lives. This was followed by relatively minor landslips in Idukki and Kottayam on July 31, triggered by heavy rainfall, which claimed four lives so far. Is Kerala’s landscape highly vulnerable to landslides during the monsoon? Yes. Kerala receives around 3,000 mm of annual rainfall, often in uneven, high-intensity spells that are becoming more frequent and extreme, exacerbated by global warming and climate change. Its steep terrain, weathered soils and complex geology make the State highly susceptible to landslides. For instance, in 2018, an anomalous monsoon brought around 36% excess rainfall over the seasonal normal and triggered as many as 4,728 landslides across Kerala, killing 48 people. These landslides were associated with a single extreme rainfall event on August 16. The State witnessed another spate of devastating landslides in subsequent years. In 2019, the Puthumala landslide in Wayanad killed 17 people, while the Kavalappara landslide in Malappuram claimed 59 lives.
Both occurred on August 8 following high-intensity rainfall. A perfect storm: On the Wayanad debris slip On October 16, 2021, catastrophic landslides struck parts of Idukki and Kottayam, with the worst incidents occurring at Kokkayar in Idukki and Palappally and Kavali near Koottickal in Kottayam. The most disastrous landslide in Kerala’s history occurred in 2024, when the villages of Mundakkai and Chooralmala in Wayanad were devastated by a landslide on July 30, claiming 231 lives, while 41 people remain missing. Although extreme rainfall was the immediate trigger for most of these disasters since 2018, their geographical distribution and human interventions also heighten the susceptibility of several parts of the Western Ghats to landslides. How serious is the situation in Kerala now? Compared with several Himalayan States, Kerala has recorded fewer landslide events. Yet, its share of landslide fatalities is disproportionately high, largely because of its dense population and extensive settlement in vulnerable areas. This is underscored by the Landslide Atlas of India, prepared by the Indian Space Research Organisation’s Remote Sensing Centre, Hyderabad, and released in 2023. Based on landslide events recorded between 1998 and 2022, the atlas shows that although the Western Ghats experienced fewer landslides than the Himalayan region, Kerala remains highly vulnerable. Around 4.75% of Kerala’s total area is classified by the Kerala State Disaster Management Authority as a high landslide hazard zone.
The BriefWire