A research team from the federal technology institute ETH Zurich studied debris flows in canton Valais with unprecedented precision to better understand the factors that determine how destructive they are. The international team led by ETH Zurich studied first-hand the triggering of a torrential debris flow in June 2022 in the Illgraben cirque above the Valais municipality of Leuk. +Get the most important news from Switzerland in your inbox No less than 25,000 cubic metres of material – water, earth and scree – poured down four kilometres into the Illbach riverbed before flowing into the Rhône, ETH Zurich wrote in a press statement on Wednesday. Scientists monitored the natural phenomenon at several measuring stations, using high-precision 3D laser scanners known as LiDARs. At the top of the valley, a rapidly advancing two-metre-high front was observed at the tip of the flow, containing large boulders up to a cubic metre in size. Further down the valley, the debris flow was slower ...
