Summary:
On 27 May 2026, a case was brought against the Swiss canton of Valais concerning its liability for the Blatten landslide disaster, which took place one year previously, on 28 May 2025. On that date, the collapse of the Birch glacier destabilized the mountainside above the village, the Petit Nesthorn, causing a landslide of ice, mud, and debris that buried 90% of the village of Blatten in Valais’s Lötschental valley. Although the residents of the village were evacuated, the events resulted in one death. In addition, 130 houses as well as the local church were swept away and buried under debris 200 m thick.
One year after the disaster, legal collective “Avocat.e.s pour le Climat” brought a case on behalf of Jean-Marc Tétaz, a philosopher and theologian who lost his home and his life’s work, a library comprising 5000 sources, as well as ongoing research work and handwritten family memoirs, in the disaster. In a conciliation request filed with the municipal court of Sion, he claims the balance of damage not covered by liability insurance, including for the loss of his books, manuscripts, and work notes, as well as lost earnings from publishing projects that cannot be completed. The damage claim amounts to 211,900 Swiss Francs.
The case reportedly argues that the canton of Valais failed act to avoid the disaster or provide information to the public despite having been aware of the risks since 2022, when an “imminent danger” was identified, with a collapse deemed “very likely”, by scientists from the Swiss Federal Institute for Forest, Snow and Landscape Research, who modeled the potential consequences of a landslide at the Petit Nesthorn. According to the plaintiff in this case, the canton of Valais dismissed the scientists’ finding and failed to inform local residents of the dangers, which would have allowed him to relocate his library.
The plaintiff links the glacial instability and permafrost thaw that caused the Blatten disaster with climate change, citing scientific studies that identify climate change as having a role in the disaster. He argues that the cantonal government negligently ignored the risks given its lack of an ambitious climate policy.
More information on this case, and its legal foundations, will be added when it becomes available.
Suggested citation:
Municipal court of Sion, Tétaz v. Canton of Valais, conciliation request filed 27 May 2026.
Last updated:
30 May 2026.