Overview

• A collapse of rock and ice from the Kleine Nesthorn on May 28 triggered the Birschgletscher to crash into the valley, forming a nine million cubic meter debris cone that buried most of Blatten and left one resident unaccounted for.
• The lake held back by the debris has dropped by one meter to roughly 800,000 cubic meters as the Lonza gradually carves channels through the blockage.
• Cantonal authorities have installed floating barriers on the lake and lowered water levels at the Ferden power plant to prevent sudden mudflows or downstream flooding.
• Geologists warn the debris cone remains highly unstable and that further rockfalls, driven by forecasted rain and ongoing ice melt, could spark new landslides.
• All 306 villagers were evacuated ahead of the collapse, with psychological support services deployed and local officials now preparing detailed reconstruction plans.