A massive glacier collapse in the Swiss Alps on May 28, 2025, unleashed a torrent of ice, rock, and mud that buried approximately 90% of the village of Blatten, located in the canton of Valais. The village’s 300 residents had been evacuated earlier in May after warning signs emerged, but a 64-year-old man remains missing, prompting ongoing search efforts.
The landslide, suspected to be a consequence of climate change weakening alpine permafrost, has created a large natural dam obstructing the River Lonza and forming a swelling lake that risks further flooding. The debris spans nearly two kilometers and is trapping up to one million cubic meters of water daily.
Experts attribute the collapse to melting permafrost and shifting mountain materials exacerbated by rising temperatures. Matthias Huss, head of the Glacier Monitoring in Switzerland (GLAMOS), pointed to the likely influence of climate change in loosening the rock mass in the permafrost zone, which triggered the collapse.
Some more data:
- 130+ Blatten buildings buried under gravel
- First warnings issued a week ago, prompting evacuation
- Smaller collapses already observed yesterday
- ~1M m³ water accumulation expected every 28 hours from the Lonza River over the next weeks
There are experts worth following on this topic:
• Luca Malatesta, geomorphology specialist
• Melaine le Roy, glacier researcher
The event highlights the increasing threat of climate-driven natural disasters in alpine regions. Residents of Blatten, now displaced and devastated, are left grappling with the loss of their homes and community.
Authorities continue to monitor the situation closely, with rescue teams searching for the missing resident and assessing the risk of further flooding due to the natural dam formed by the debris.
Birchgletscher | Glacier de Birch Credit: Thanks to Pomona, SRF – Schweizer Radio und Fernsehen, Le Temps for survailance images, drone images and data.
