A massive avalanche of ice, mud, and rock struck the village of Blatten in Valais, Switzerland, on the afternoon of May 28, 2025, obliterating about 90% of the settlement. The collapse of the Birch glacier at 3:30 p.m. triggered a landslide that buried homes, infrastructure, and the Lonza river, which runs through the Lötschental valley. Approximately 300 residents had been evacuated on May 19 following geologists’ warnings of imminent danger. Despite the evacuation, a 64-year-old man was reported missing.
Local authorities had been monitoring the glacier since early May, when signs of instability were detected. Drone footage revealed an unrecognizable landscape, with mud and debris covering the village and surrounding forests. Swiss President Karin Keller-Sutter expressed solidarity with the residents, acknowledging the pain of losing their homes.
- Location: Blatten, Lötschental valley, Valais canton.
- Event date: May 28, 2025, at 3:30 p.m.
- Debris volume: Approximately 3 million cubic meters.
- Missing person: A 64-year-old man, details undisclosed.
The event, described as unprecedented by experts, underscores growing concerns about alpine glacier instability amid climate change. The situation remains critical, with risks of further landslides.
Prior evacuation prevented greater tragedy
The evacuation of Blatten, ordered on May 19, was pivotal in averting a higher casualty toll. Geologists identified the risk of the Birch glacier’s collapse after weeks of monitoring, noting movements of up to 1.5 million cubic meters of rock and ice. About 300 residents, along with 190 sheep, 26 cows, and 20 rabbits, were relocated, with one injured cow airlifted by helicopter.
The operation, coordinated by Valais authorities, showcased community solidarity. Mayor Matthias Bellwald praised residents for their swift cooperation. The decision stemmed from expert analyses, including warnings from geologist Alban Brigger about the potential for debris to dislodge massive ice formations, worsening the disaster.
- Evacuation date: May 19, 2025.
- Evacuated residents: Approximately 300 people.
- Relocated animals: 190 sheep, 26 cows, 20 rabbits.
- Initial risk: 1.5 million cubic meters of unstable material.
Birch glacier: a monitored threat
The Birch glacier’s collapse followed signs of instability observed since early May. Experts recorded minor landslides on the night of May 27 and early May 28 before the main event. Raphaël Mayoraz, head of natural hazard management in Valais, noted that the 3 million cubic meters of debris was unprecedented, with no historical records of a similar event.
Located above Blatten in the Lötschental valley, the glacier faced pressure from 9 million tons of accumulated rock, triggering the landslide. Drone footage broadcast by Swiss outlet SRF showed a vast mud plain covering the village, with remnants of wooden structures scattered amid the debris. Federal Councillor Albert Rösti called the event extraordinary.
Destruction in numbers
The landslide razed about 90% of Blatten, leaving few structures intact. Homes, buildings, and local infrastructure were buried under a mass of ice, mud, and rock that reached the opposite valley slope. The Lonza river, running through the village, was blocked, raising concerns about potential flooding.
Stephane Ganzer, Valais security chief, described the situation as critical, with the possibility of further collapses. Authorities closed the main valley access road, warning of ongoing dangers. Social media footage captured the moment of the collapse, with a dust cloud engulfing the mountain.
- Affected area: Approximately 90% of Blatten village.
- Displaced material: 3 million cubic meters of ice and rock.
- Infrastructure: Homes, buildings, and Lonza river severely impacted.
- Access: Main road closed for safety.
Climate change amplifies risks
Accelerated glacier melting, driven by climate change, has heightened instability in regions like Valais. The World Meteorological Organization reported that Swiss glaciers lost 10% of their volume in the past two years. The Aletsch glacier, the largest in the Alps, has retreated over 1,300 meters since 1984, per the Swiss Glacier Monitoring Network.
Global warming, with Alpine temperatures rising twice as fast as the global average, contributes to events like Blatten’s. The intense heat of summer 2024 melted accumulated snow, reducing glacial volume by up to 2.5%. Experts warn that, without emission reductions, Alpine glaciers could lose 80% of their mass by 2100.
Authorities’ response
Swiss authorities acted swiftly post-collapse, intensifying monitoring of the Birch glacier. Emergency teams plan to install additional surveillance systems to assess risks of further landslides. President Karin Keller-Sutter took to social media to offer support, emphasizing the severity of losing homes.
Emergency services declared the area a risk zone, urging residents and onlookers to stay away. The main road remains closed, and access to the Lötschental valley is restricted. Jonas Jeitziner, from the emergency management service, confirmed multiple homes were destroyed, but the prior evacuation minimized human losses.
Community grapples with loss
Blatten’s mayor, Matthias Bellwald, stated that while the village was lost, the community’s spirit endures. Before the evacuation, the 300 residents showed unity, organizing the departure of people and animals. The destruction of homes and personal memories has sparked widespread sympathy, with support messages flooding social media.
Videos shared by users captured the landslide’s force, with debris racing down the mountain. The avalanche reached the opposite valley slope, highlighting the event’s scale. The search for the missing man continues, though authorities have not released details about his identity or circumstances.
- Mayor’s statement: “We lost the village, but not our heart.”
- Community support: Residents united during evacuation.
- Search efforts: A 64-year-old man remains missing.
Risk of further collapses
The Birch glacier’s instability persists, with experts warning of potential additional landslides. The unstable mass of rock and ice above Blatten is under constant surveillance, though weather conditions like fog hinder assessments. Engineer Alban Brigger noted that smaller landslides are preferable to another massive collapse.
Authorities declared a “special situation” in Lötschental, reinforcing safety measures. Monitoring systems will be expanded in the coming days, focusing on preventing further damage. The Lonza river’s blockage also raises concerns about damming and flooding risks.
Environmental toll in focus
The Birch glacier collapse reflects a pattern of extreme events in the Alps, driven by glacial retreat. The Aletsch glacier lost 43 meters of water equivalent over four decades, per GLAMOS data. Smaller glaciers like Oberaletsch and Fiescher have receded by 240 and 1,000 meters, respectively.
Melting impacts more than just villages like Blatten; it affects Alpine traditions. Farmers face challenges with reduced meltwater, vital for pastures and rivers. The Swiss government quadrupled funding for Alpine water projects in 2022, approving 40 initiatives to address these issues.
History of similar events
Events like Blatten’s are not unprecedented in the Alps. In 2022, the Marmolada glacier collapse in Italy killed 11 people, underscoring the dangers of unstable glaciers. In 2023, the Swiss village of Brienz was evacuated twice due to landslide threats, with millions of cubic meters of rock at risk.
Melting has also uncovered relics, such as wreckage from a 1968 plane crash on the Aletsch glacier and the body of a climber missing since 1986 on the Theodul glacier. These finds, while intriguing, highlight the broader impact of global warming on Alpine landscapes.
- Marmolada, 2022: 11 deaths in Italian glacier collapse.
- Brienz, 2023: Village evacuated over landslide risks.
- Aletsch, 2022: 1968 plane wreckage discovered.
- Theodul, 2023: Climber’s body from 1986 found.
Solidarity and support
The Swiss community has rallied to support Blatten’s residents. Local organizations are providing temporary aid, while authorities assess reconstruction possibilities. President Keller-Sutter reiterated the government’s commitment to helping affected families, though no timeline for residents’ return has been set.
Social media messages of solidarity emphasize the resilience of Lötschental’s inhabitants. Widely shared collapse videos have raised global awareness, fueling discussions about the climate crisis. The search for the missing man persists, with rescue teams battling adverse conditions.
Uncertain future for Blatten
Blatten’s destruction raises questions about the viability of Alpine villages in high-risk areas. Glaciologist Daniel Farinotti predicts that glaciers like Aletsch and Rhône could lose 68% of their mass by century’s end. The Swiss government is investing in solutions like solar pumps and water reservoirs to combat water scarcity.
Residents, now sheltered in safe areas, face an uncertain future. Rebuilding Blatten hinges on safety assessments and financial resources. The tragedy serves as a stark reminder of the urgent need for climate action, as mountain communities worldwide face growing threats.