Tuin Khola Landslide Crisis: Why Nepal’s Slopes Keep Failing

The rising Himalayas are composed of highly fractured and weathered rock masses—schist, phyllite, and quartzite—that lose their natural equilibrium when cut for roads or hydropower projects. During the monsoon, heavy rainfall infiltrates this fractured terrain, increasing pore-water pressure and drastically reducing shear strength, triggering chains of landslides, debris flows, and road closures that claim lives and disrupt the economy. The repeated slope failures at Tuin Khola along the Narayanghat–Mugling highway are not isolated incidents; they reflect chronic geotechnical vulnerability, with tens of thousands of cubic metres of debris reported in September 2025 alone and re-failures occurring during clearance work. Human activity exacerbates this instability: unplanned slope cutting often exceeds natural angles of repose, blocked or inadequate drainage saturates cut slopes, quarrying and riverbed mining undermine fragile foundations, and deforestation removes root networks that once reinforced the soil. Landslides in Nepal are therefore not merely “natural disasters” but predictable failures resulting from a dangerous combination of fragile geology, intense rainfall, and unscientific human interventions.