Engineering Geology of Recent Hydro-climatic Disasters in Nepal

Abstract

Continuous rainfall starting on September 27, 2024, triggered widespread flooding, inundation, and numerous landslides across Nepal, severely affecting various regions. With 77 out of 222 rainfall monitoring stations reporting over 200 mm of rainfall, several rivers, including the Sapta Koshi, reached dangerous levels, resulting in significant damage. Kathmandu Valley experienced record-breaking rainfall, leading to the flooding of over 1,200 homes and widespread power outages. The disaster also devastated rural districts, with landslides and flash floods severely impacting areas like Dhading, Sindhupalchowk, Koshi Province, and Bagmati Province. Infrastructure, including bridges and highways, was heavily damaged, with 23 highways affected and losses exceeding 2 billion.  The disaster caused substantial economic impacts, particularly for rural communities reliant on agriculture. The combination of weak geological formations, poorly planned roads, and inadequate slope stabilization measures contributed to widespread landslides, while rivers like the Bagmati and Trishuli experienced severe erosion. The situation highlights the urgent need for improved disaster risk reduction strategies, including better infrastructure design, urban planning, and early warning systems to mitigate future impacts in flood- and landslide-prone areas of Nepal.