The volume of the landslide that occurred on Sunday in the Maurienne valley (Savoie), leading to a suspension of rail traffic and road disruptions, is much greater than initially estimated, the prefecture said on Tuesday.
“Initially, we told you 700 m3. Today, we are able to tell you that around ten thousand cubic meters fell on Sunday, ”said Laurence Tur, secretary general of the prefecture of Savoie, during a press briefing in Modane. . The estimates were made from footage shot Monday by drones, she added.
The landslide is “still active”
“We did not expect such a volume at all. Ten thousand cubic meters is a rare event,” said David Binet, head of the ONF’s mountain land restoration agency (RTM).
“It’s still active, [mardi] morning another 10 m3 fell” from the cliff, detailed David Binet. “It is still a sign of activity which raises questions about the follow-up to be given”, he indicated, specifying that there “still remain today on the head of the cliff about 3,000 m3 unstable”. Asked about a possible link with global warming, he indicated that “we are of course on a background geological phenomenon with slow evolutions. It would have fallen one day or the other”. “It was mainly the rain that was a trigger” after the drought, he said.
Railway infrastructure “affected” and disruptions to road traffic
Three infrastructures were affected by the landslide: the A43 motorway, “the least exposed”, “did not suffer any damage to the structure a priori” but will not reopen before new expertise is carried out on Thursday, according to him . But given the disturbances, heavy goods vehicles are invited while waiting to cross the Franco-Italian border through Ventimiglia, according to Laurence Tur. In addition, a postponement of the heavy works planned from next week until December 18 at the Mont-Blanc tunnel is “a hypothesis on the table”, she said.
For its part, the railway infrastructure “is affected”, with “a lot of damage” on the tracks, signaling and galleries, indicated Béatrice Leloup, territorial director of SNCF Réseaux, specifying that “diagnoses were in progress”. “Traffic between Saint-Michel-de-Maurienne and Modane is interrupted for an indefinite period and certainly for several weeks,” she said.
As for the departmental 1006, which serves the valley, it will remain closed “for several weeks given the importance of the landslide” and the work that will have to be carried out there, indicated Jean-Philippe Laplanche, director of infrastructures for Savoie. An “operational PC” has been set up near the site and “convoys” are being organized to ensure the supply and transport of the inhabitants of the bottom of the valley, particularly affected by the disturbances, according to the prefecture. .