Everything you never dared ask about ski area safety

This involves the preventive triggering of avalanches by explosive charges in areas historically identified as being at risk. The jargon is PIDA: Plan d’Intervention de Déclenchement des Avalanches.

In Tignes alone, 150 shooting points are listed in the PIDA.

As its name suggests, the Régie des Pistes is responsible for making… the slopes safe! But its scope of intervention is much broader.

As such, pisteurs are responsible for the safety of people working in the ski area (groomers, lift technicians, etc.), as well as roads and homes below the slopes that could potentially present a hazard.

I’d like to take this opportunity to remind you that off-piste areas are, by definition, never safe. So be careful!

We rely on three main sources of information to help us make decisions:

1. Snow and weather forecast from Météo France in Bourg-Saint-Maurice: snowfall, temperature, wind…
2. The Bulletin d’Estimation du Risque d’Avalanche (or “BERA”) for the Haute Tarentaise / Vanoise / Beaufortin / Bauges massif: it indicates the level of avalanche risk (from the lowest level, 1/5, to the highest level, 5/5) according to exposure (north, south, east, west).
3. Observations by sector managers in the field throughout the day.

We decide on the operation to be carried out each day before 4pm.

In the rare event of a serious avalanche hazard, a safety commission is convened. It brings together the commune’s mayor, the Régie des Pistes, the ski lifts and technicians (guides, instructors, etc.). Based on everyone’s observations and recommendations, an action plan can then be activated (road closures? Containment measures? Setting up emergency accommodation?)

We use several security systems:

• Hand grenading, which remains the most precise way of preventively triggering avalanches.
• CATEXs, which consist of a cable that carries explosive charges to points listed in the PIDA. We have two of these in Tignes: above the road between Le Lac and Tignes 1800, and above the Mélèzes trail down to Les Brévières.
• Some forty GAZEX, which can be used to remotely trigger explosive charges located in a safe. Their big advantage is that they can be used to secure hard-to-reach areas (without putting people at risk). They can even be detonated at night, to ensure the safety of the groomers criss-crossing the estate.
• Two avalanche transceivers, which can be compared to cannons that fire arrows that explode on impact (unreliable in high winds, of course).
• Last but not least, the helicopter provides access to specific shooting points that are difficult to access, dangerous or out of the way. Of course, good visibility is essential for flying…

You won’t miss them: the explosions, always impressive, are quite loud! Especially when the shots are fired in loudly resonant areas.

CATEX and GAZEX can be triggered as early as 4:00 or 5:00 am.

On the other hand, we have to wait for the first light of day, at around 7:00 am, to start shooting by hand. The safety of our personnel is of course our top priority: if visibility is insufficient, we may have to delay the deployment of our teams.

Please note: if conditions change during the day (in the event of heavy snowfall or major temperature variations, for example), it may be necessary to re-secure certain areas. This explains why a trail may well be open in the morning, only to close again a few hours later. Don’t venture out! A trail is never closed by chance…

Please note: contrary to what you might think, it is unfortunately impossible to secure the area the day before for the following day, even on a clear night. The wind can shift a lot of snow in just a few hours, creating new wind patches… which would have to be secured again the next morning!

It really depends on the weather conditions : is visibility good? Is access to the shooting points easy, or complicated by heavy snowfall? Is it necessary, or not, to set off all the shooting points? Not to mention the indispensable task of restoring slopes (or clearing roads) after avalanche control has been triggered.

In short: we do our utmost to be ready “on time”, but sometimes this isn’t possible when conditions are exceptional. We are responsible for skiers’ safety, and when you have such a responsibility on your shoulders, you’d rather delay the opening of a run than risk an accident.

All the pisteurs are deployed at the same time in teams of two on the four sectors (Tovière, Grande Motte, Palet, Aiguille Percée) according to a well-defined plan. Some sectors take longer than others to secure, depending on their configuration (longer or shorter approach steps, for example).

It should be noted that, as a general rule, all sectors are secured every day (with a few exceptions: in spring, for example, only the Grande Motte sector needs to be secured).

This is not a neutral operation, as it means closing the road. As far as possible, we are trying to limit traffic disruption by securing the road between Le Lac and Tignes 1800, either late in the evening (around 10:00 pm) or early in the morning (around 4:00 am).

On the other hand, securing the road downstream of the Brévières tunnel (under the “Davie” slopes) is far more complex. It can only be done by day, as the shots are fired from a helicopter. It’s a sector we monitor on a daily basis with beacons, but also quite simply with… a telescope! And, of course, we take into account the recommendations of the departmental council’s snow expert).

If I had to pick just two :

1. Respect the signs: a trail is never closed by chance.
2. For ski tourers, who by definition don’t take ski lifts (and therefore don’t necessarily see the banners at the top of the slopes indicating whether they are open or closed): remember to check at the bottom of the lift whether a safety operation is underway in the area. And if in doubt, ask the ski patrol before you set off.