Swiss authorities remained on high alert Friday after a massive glacier collapse buried large parts of the alpine village of Blatten in the Lotschental Valley, triggering a crisis response and urgent search efforts.
The Birch Glacier broke loose Wednesday afternoon, unleashing a torrent of mud, ice and rock that Swiss seismologists called “one of the largest mass movements ever recorded.” The force of the collapse was so immense that seismic signals were detected hundreds of kilometers beyond Switzerland’s borders.
Although Blatten had been evacuated as a precaution on May 19, one man, a 64-year-old who defied warnings, remains missing. Search operations are ongoing, but treacherous terrain continues to hinder rescue teams.
In response to the disaster, the canton of Valais declared a “special situation” early Wednesday to fast-track emergency measures. More than 50 Swiss army personnel have been deployed, with additional troops and heavy machinery on standby. However, unstable conditions have made direct intervention extremely dangerous.
The collapse also formed a natural dam in the Lonza River, creating a temporary reservoir that authorities fear could breach without warning. Experts warn of a high risk of a tidal surge and rapid erosion. Aerial surveillance and drone reconnaissance continue around the clock.
Downstream communities – including Steg-Hohtenn and Gampel-Bratsch, home to more than 2,000 people – have been advised to remain on alert and prepare for immediate evacuation.
“We urge residents to pack essential items and be ready to leave immediately,” local authorities announced.
The Ferden Dam, located farther downstream, has been emptied to act as a catchment basin in the event of flooding. Officials are cautiously optimistic that it can withstand the pressure.
“Even with enormous influences, this wall will hold,” said Christian Studer from the canton’s Natural Hazards Department.
With further landslides still possible, authorities are focusing on risk assessment and minimizing the number of people in vulnerable areas.
Speaking on the incident, World Meteorological Organization (WMO) spokesperson Clare Nullis told reporters in Geneva that early warnings and swift action by Swiss authorities likely prevented a greater tragedy.
“Luckily, there are no confirmed casualties or deaths at the moment – just one person reported missing,” Nullis said.
She emphasized the critical role of early action and coordination, saying, “That shows the importance of early warnings and early action. The Swiss authorities did do everything – it was like a textbook example of what should be done.”
“The landscape will never be the same again,” she added. “But it is an example of how we can use forecasts and warnings to save people’s lives.”
Nullis also warned that the threat is not over, urging continued vigilance in the region.
At a news conference Friday, Valais State Councilor Stéphane Ganzer said, “Safety for emergency services has not yet improved.” As a result, operations in the affected area remain suspended. Still, he described the situation as “developing positively for Gampel and Steg,” and said no evacuations are currently planned for the two villages.
“The risk remains, even if it is decreasing. We remain cautious,” he said.
Regarding efforts to find the missing man, Studer said officials are awaiting a final assessment from hazard specialists before resuming search operations.
“We are optimistic and are waiting for a definitive go-ahead,” he said.
President Karin Keller-Sutter confirmed that Environment Minister Albert Rosti will present initial plans at the next Federal Council meeting outlining how the federal government can support recovery efforts in Blatten.
In the meantime, work is underway to secure temporary housing for displaced families.
Studer added that consultations with external experts from ETH Zurich have not revealed any imminent threats.
“We currently don’t anticipate anything major and can continue with the current measures,” he said.
He also noted a key development: the Lonza River has reached its first high point on the debris pile, and overflow behavior is being closely monitored.
“This will allow us to better understand and respond to any changes in flow dynamics,” he said.
