A 250-metre-long crack on a mountainside in Valais is rapidly widening due to extreme rainfall, prompting concerns of a potential landslide that could block the Navizence River and flood the village of Chippis.
"Growth has been relatively constant: between 2-4 millimetres a day."
"It’s a considerable amount of material and potentially a substantial cascading hazard."
A staggering 250-metre-long fracture is tearing through the Val d’Anniviers, serving as a grim monument to the Alps' increasing fragility. This geological scar, known as the 'Faille des Fios', is not a static relic of the past; it is a living, breathing threat. Geologists confirm the crack is widening at a relentless rate of 2 to 4 millimetres every single day. While that may sound incremental, in the world of geology, it is an alarmingly rapid pace that signals a slope in active distress. Currently gaping up to one metre wide, the main fracture has begun spawning secondary cracks that spiderweb across the terrain like dark, ominous tributaries. The mountain is no longer holding its ground; it is surrendering to gravity. As snowmelt begins to infiltrate these openings, the internal pressure mounts, turning a local geological curiosity into a ticking time bomb for the Rhone Valley below. This is the new reality for Switzerland’s high-altitude regions, where the very foundations of the landscape are being rewritten by environmental stress.
Nearly 500,000 cubic metres of rock and debris are poised to plummet into the valley, creating what experts call a 'cascading hazard.' This volume of material, while smaller than the catastrophic 30-million-cubic-metre Randa slide of 1991, carries a unique and deadly potential. If the mass collapses, it will not simply stop at the base of the mountain; it will choke the Navizence River. This blockage would create a natural dam, causing water to back up before inevitably bursting through in a violent, unpredictable surge. Raffaelle Spielmann, an engineering geologist at ETH Zurich, warns that this scenario represents a 'substantial cascading hazard' where one disaster triggers another. Unlike the 2025 Blatten landslide that wiped out a village with sheer volume, the danger here is the precision of the threat to the water systems. The geography of the Val d'Anniviers acts as a funnel, meaning any significant movement at the Fios scarp translates directly into a life-threatening event for those downstream. The mountain doesn't need to disappear to cause a catastrophe; it only needs to move enough to turn the river into a weapon.
Extreme precipitation is the undisputed architect of this crisis. The fracture didn't appear in a vacuum; it is the direct result of the violent flooding events of 2018 and 2024. During these periods of unprecedented rainfall, the Navizence River transformed into a torrent so powerful it eroded its own bed by several metres. This process effectively 'amputated' the foot of the mountain slope, removing the structural support—the geological 'toe'—that held the upper rock masses in place. Without this foundation, the slope began to slump under its own weight. Local geologist Michael Digout points out that rainfall now plays a dual role: it continues to destabilize the riverbank while simultaneously lubricating the internal fissures. As water and melting snow pour into the 250-metre crack, they act as a wedge, prying the mountain apart from the inside out. This is a textbook example of how climate-driven weather extremes are accelerating geological timelines, turning processes that should take centuries into events that unfold over months. The Alps are grappling with a climate that is moving faster than the rock can adapt.
More than 1,500 residents in the village of Chippis now live under the shadow of a mountain that could move at any moment. Authorities are refusing to leave safety to chance, having already finalized rigorous emergency evacuation plans. Civil protection shelters have been prepped, and spots are officially reserved for the entire population should the 'extreme scenario' materialize. While geologists like Michael Digout suggest the mass might move in successive, smaller phases rather than one singular collapse, the mandate for public safety requires preparing for the absolute worst. The village, situated in the Rhone Valley, sits directly in the crosshairs of any potential flood surge. This heightened state of readiness is a harbinger of things to come for Alpine communities across Switzerland. As the climate warms and the peaks become more unstable, the cost of living in the mountains is rising—not just in Swiss francs, but in the constant vigilance required to survive. For the people of Chippis, the widening crack in the Val d’Anniviers is more than a geological phenomenon; it is a daily reminder of their vulnerability in a changing world.