More than 200 tremors have shaken the canton in early November, and the authorities predict a more sizeable earthquake will hit the area at some point in the coming years or decades.
In a worst case scenario natural disaster experts in Valais believe a 6.5 magnitude earthquake striking between the cities of Sion and Sierre could leave 800 dead, 1,600 buildings destroyed and 119,000 people homeless, according to Thursday’s “Le Nouvelliste” newspaper
And if this extreme scenario can statistically occur every 475 years, an earthquake of lower magnitude, around 6 on the Richter scale, is likely to occur in Valais in the coming decades, experts say.
According to “Le Nouvelliste”, the canton’s “weak point” is its housing.
Only 10 to 20 percent of the buildings meet the seismic standards established in 2004. But the vast majority were built before this date.
“That does not mean that these buildings will collapse at the slightest jolt, but only that we have doubts about their resistance”, an expert told Le Nouvelliste.
According to the Cantonal Concept Preparation and Response in the Event of an Earthquake (COCPITT), it would take “no less than three generations” for all of Valais structures to be able to withstand a major earthquake.
Meanwhile, the authorities have prioritized public buildings, especially those with high concentrations of people and those serving vital functions, such as hospitals.
While these cantonal buildings of high importance have all been “treated and analysed”, this is not the case for buildings which the canton is renting and whose upgrades are not within its competence, for instance schools.
And the same goes for privately-owned buildings.
“Communes and private individuals are responsible for their constructions. But the law does not require that old buildings be brought up to standard, except in case of renovation”, the cantonal architect Philippe Venetz told Le Nouvelliste.