“The world is warming, which means that more rock slope failures and glacier avalanches are likely in the coming decades,”
A devastating avalanche and flood in Nepal’s Rasuwa district on 26 August killed more than 1,400 people, destroyed infrastructure, and displaced tens of thousands, according to a study.
Avalanches Strike Nepal
The disaster, one of the largest on record, was triggered by a 125 million cubic meter rock and ice avalanche that surged down mountain valleys, melting ice and picking up sediment before flooding communities. Researchers warn that such events are becoming more frequent as global warming accelerates, destabilizing glaciers and slopes. “The world is warming, which means that more rock slope failures and glacier avalanches are likely in the coming decades,”
the study states.
In 2023, a similar glacial sediment slide into South Lhonak glacier lake in Sikkim, India, triggered an outburst flood that transported 270 million m3 of sediment down the Teesta River, killing more than 100 people and damaging 26,000 buildings. The Rasuwa flood followed a pattern of cascading hazards, including collapses of steep rock or glacier slopes, failures of sediment banks, and outburst floods, which the study links to climate-driven instability.
The flood’s impact extended over 100 kilometers. More than 5,000 people went missing and 10% of Nepal’s hydropower production was knocked out.
“This river can overflow if the glacier collapses or if the glacial lake bursts, and we live in constant fear.”
said Krishna Gauchan, a hotel owner near the Modi River, highlighting the peril faced by communities and tourism infrastructure.
Himalayan Building Boom
A separate report reveals that 300,000 people in the Himalayan region now live in areas at risk of glacial lake outburst floods and landslides.
Between 2016 and 2023, built-up land in high-risk zones grew by 45%. Development near glacial lakes rose 78%.
“This river can overflow if the glacier collapses or if the glacial lake bursts, and we live in constant fear.”
said Krishna Gauchan, a hotel owner near the Modi River, highlighting the peril faced by communities and tourism infrastructure.
The study also found that in areas threatened by glacial lake flooding, development increased by 78% between 2016 and 2023, with many old buildings located just 5m (16ft) from river banks despite regulations requiring greater setbacks.
Energy and Tourism Risks
“The destruction of hydropower sites also affects neighboring countries that depend on energy imports, including Bangladesh.”
the study notes, citing Bangladesh’s energy dependencies.
In 2021, a glacial lake burst in Nepal’s Melamchi River sent floodwaters surging through the region, while an avalanche from Ronti peak in Uttarakhand, India, caused a deadly flood in February 2021. These events highlight the region’s vulnerability, with scientists stating that Himalayan warming occurs at twice the global rate.
The Hotel Association Pokhara president, Laxman Subedi, criticized tourism expansion in the region, stating businesses have grown “without any proper planning” and been promoted “haphazardly.” “By the time disasters strike, it is too late,”
he said.