Bad Hofgastein

“The Ingelsberg is on the move again”

The experts (top right) look tiny compared to the mass of rock.

(Bild: LMZ)

The slope high above Bad Hofgastein has been unstable for generations: a fully technical monitoring system has been installed to protect the residents in the valley below. The rock can even send text messages if it moves quickly. Another alarm has just been received.

"Attention! There is currently increased danger on the Ingelsbergweg!" warns the municipality of Bad Hofgastein on its website. Hiking is currently prohibited in this sensitive area. There is a danger to life. Alarming text messages have just been received again from the fully automatic monitoring system at the edge of the unstable slope. While continuous rain pours down on the whole of Austria, the Ingelsberg is also on the move.

The rock face is located to the north of the municipality of Bad Hofgastein: around 400 meters above the village, up to 100,000 cubic meters of rock material are lurking on the edge.

Monitoring with measuring rods in crevices
In 2017, 500 cubic meters of rock thundered down into the valley. And the risk remains. Because spontaneous collapses are possible, a fully automatic monitoring system was installed. "We protect the settlement area below," says regional geologist Gerald Valentin.

Geologically speaking, the Ingelsberg is one of the most dangerous slopes in the province of Salzburg. At the moment, however, we can say that nothing major is to be expected.

Gerald Valentin, Landesgeologe

High-tech on the mountain makes this possible. There is no longer any need for costly reconnaissance flights or inspections. The mountain can be monitored from anywhere. Valentin: "There are measuring rods stretched across the crevices that are accurate to a tenth of a millimetre." If the gap widens, the technology sounds the alarm. Four cameras and floodlights also assist with monitoring.

Unstable slope reacts to rainfall
Valentin is currently monitoring the Ingelsberg with a few clicks from his vacation: "We've received several text messages." But he can give the all-clear: "There are no signs that anything major could happen." Why has another rockfall alert been received right now? "The mountain reacts to precipitation ranging from heavy rain to melting snow," says Valentin. Water ingress and subsequent exposure to sunlight can also have a powerful explosive effect on the rock.