How We are Protected Against Avalanches

Soon after people started to settle in mountainous regions, they recognized the danger of avalanches. In order to stop the snow from burying their homes, they planted so-called ban forests on the slopes above their settlements. In many cases this protection was effective, which is why until today ban forests are still cared for by the local authorities. They are the best natural defense against avalanches. However, experience has shown that the forest must be dense and contain several hundred trees for every 2.5 acres [1 ha], as well as older and younger trees of different species.

In recent times engineers have made metal barriers anchored in concrete. These are placed in breakaway zones above the first fence of trees. They can be constructed up to 4 m in height, but it would be too expensive to place them on every slope. To protect buildings from being swept off their foundation, avalanche breakers are also made of huge mounds of rock and dirt and are set at the bottom of slopes. These piles can divert avalanches and keep them from rushing into villages and homes in valleys. Other types of breakers are V-shaped walls of dirt 2 m thick and 5 m high. The point of the V faces uphill, so it can split an avalanche in two and force the snow to deflect to either side. The legs of the V measure 90 m or 120 m in length and can protect entire towns. However, when important main roads or railway lines in the valleys are threatened, the best protection—and the costliest too—is provided by tunnels or galleries made of wood, steel, and concrete.

Another way to prevent avalanches is to break up heavy masses of snow. The Canadian army, for example, patrols between towns each winter and shoots into the snow. In this way they guard the Trans-Canada Highway, breaking up snow before it can avalanche and cover the road. To a certain extent, this method is also used in Switzerland, where in an effort to prevent avalanches, explosives are shot or dropped from helicopters onto unstable slopes to dislodge snow.

Avalanche Rescue

Skiers and hikers are supposed to wait while slopes are being tested for safety. Never ignore posted warnings! Remember that even the most experienced professional skier can be buried in snow. If you are caught in an avalanche, don’t panic! Move as if you were swimming in the ocean, advise experts. This will help to keep you near the top of the slide. Or push one arm as high as possible overhead. This might alert rescuers to your position. Cover your mouth and nose with your other hand. Rescue statistics show that only half of avalanche victims survive after being trapped for more than 30 minutes. Nowadays, some skiers carry beacons, such as battery-operated transmitters. Since the white death is ever present in high altitudes, speedy efforts to rescue avalanche victims are necessary.

For centuries, the famous Saint Bernard dogs were raised by Augustinian monks in the Swiss Alps. These dogs had the strength and stamina to move through deep snow and to withstand freezing winds and cold weather. They had a good sense of orientation and were very sensitive to sound and motion undetectable by humans. They thus saved hundreds of lives, even though they did not carry a keg of brandy on their collar while on rescue missions, as many pictures have portrayed them! Today most rescue dogs are German shepherds, but some other breeds are also trained for this type of work. In addition, electronic aids are effective, and careful probing by rescue workers can save lives. They cannot, however, match the success of trained dogs.