A Swiss mountain village in the southern canton of Valais remains on high alert after a rockfall and increasingly unstable terrain forced the evacuation of dozens of residents over the weekend, local authorities said Sunday. The village of Blatten, nestled beneath the Kleiner Nesthorn mountain (3,341 meters), was partially evacuated Saturday evening after monitoring data confirmed accelerating geological movement on the slope above. Swissinfo.ch reported that 92 residents and 16 guests were evacuated in a calm and orderly operation.
In a statement cited by Swiss news agency Keystone-SDA, local officials said the affected slope has become “increasingly dynamic” in recent days. A reconnaissance flight Saturday morning and ground measurements confirmed that the mountain has sunk by several meters, with large cracks forming in the terrain. Rockfalls and ongoing movement are continuing to be recorded.
The Birch Glacier, situated below the site of the recent rockfall, has been under observation since the 1990s. On Saturday, falling rocks struck the glacier, triggering a debris flow that stopped roughly 500 meters (1,500 feet) above the River Lonza, just outside Blatten. Authorities suspect that snowmelt around 2,500 meters (8,200 feet) in elevation may have contributed to the destabilization. The local road between the villages of Ried and Blatten remains open daily between 5 a.m. and 9:30 p.m., but is closed overnight as a precaution.
Municipal leaders emphasized the importance of compliance with safety measures, urging residents and visitors to respect barriers and avoid entering the evacuated zone. “The risks are constantly being reassessed,” officials said in the statement. “An adjustment to the evacuation perimeter cannot be ruled out.” The first night after the evacuation was reported to be calm, with all evacuees able to secure suitable accommodations, the municipality added. The situation in Blatten remains fluid, with authorities continuing to monitor the slope and reassess conditions on a continual basis.
