Avalanche control

The prevention and mitigation plans combine extensive snow pack observation with three major groups of interventions: active, passive and social - sometimes more narrowly defined as "explosive", "structural", and "awareness" according to the most prevalent technique used in each.

For the event of human involvement, avalanche control organizations develop and train exhaustive response and recovery plans.

In areas of heavy human use the snow pack is monitored throughout the winter season to assess its evolution under the prevailing meteorological conditions.

In the smallest terrain features the simplest method of avalanche control that disrupts weak snow layers by directly walking through them, a technique referred to as boot packing.

This has the combined effect of reducing the objective hazard posed by the cornice, and providing a large impact force on the snow pack.

Explosive techniques involve the artificial triggering of smaller less destructive avalanches, by detonating charges either above or on the snow surface.

The explosives may be deployed by manually hand tossing and lowering, by bombing from a helicopter, or by shelling with a howitzer, recoilless rifle, or air gun.

The magazines can be transported, loaded, and removed from the towers by helicopter, without the need for a flight assistant, or on site personnel.

[1] Permanent techniques slow, stop, divert, or prevent snow from moving; either completely or to enough of an extent that the destructive forces are significantly lessened.

Permanent techniques involve constructing structures and modifying terrain for purposes classified as:[1] A single intervention may fulfill the needs of multiple classes of purpose, for example, avalanche dams, ditches, earth mounds, and terraces are used for deflection, retardation, and catchment.

Although unused today, the Central Pacific Railroad had a complete rail yard under a roof on Donner Pass.

Typical responses span from clearing transportation corridors of avalanche debris, to repairing industrial and recreational facilities, to search, rescue, and recovery.

Recreational response to avalanches involves the rapid formation of an ad hoc search and rescue team.