Avalanche mitigation can be divided into two categories - structural and non-structural. Non-structural methods include avoidance (through land use restrictions or temporary evacuation) and artificial triggering. Structural measures include diversion structures, dams, retarding structures and starting zone structures design to prevent avalanche initiation. Forest management can also be used to mitigate avalanche hazards.
The following are the most commonly used methods for protecting people and infrastructure from the potentially destructive forces of snow avalanches. The list is in approximate order of increasing cost.
| | Artificial Triggering (Active Control) Artificial triggering of avalanches is a widely used cost-effective method for protecting roads, railroads, ski areas and other sites that can be efficiently and completely evacuated, and there is little or no risk of property damage. The use of artificial triggering to protect permanent valuable facilities such as houses is controversial and generally avoided in the United States because of the potential for unintended consequences and acceptance of responsibility for damages.
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Avalanche Zoning
Avalanche zoning is probably the most reliable means of minimizing risk in avalanche terrain. However, the costs for obtaining high-quality avalanche hazard maps can be significant, andregardless of effort, hazard zone boundaries will entail some uncertainty. Also, restrictions on land use and increased construction costs in moderate "Blue" hazard zones is a major political obstacle, especially in mountain resort communities with limited gentle terrain and high land values.
| AfforestationPreservation and protection of forests in avalanche starting zones is one of the oldest and most widely usedavalanche mitigation measures. The Swiss recognized the value of forests for avalanche protection and enacted legislation in 1876 preventingforest removal above villages in avalanche areas. In North America, timber harvesting has created new avalanche hazards and resultedin a better understanding of the relationship between forests and avalanches. |
Structural Defenses
Structural Defenses include avalanche dams & retarding structures, starting zone structures, avalanche sheds and direct protection by strengthening the structure itself to withstand impact. Wherever high value resources are exposed and the risk is high or the consequences are unacceptable, structural defenses are warranted. Copyright 2014, Arthur I. Mears, P.E., Inc. & Wilbur Engineering, Inc.
FAQs
Static defense structures are mitigation measures installed in the initiation zones in order to prevent avalanches in their first stage of occurrence. Two examples are snow nets and flexible-net snow rakes. They consist of nets strung with steel wire ropes between posts and anchored to the ground.
What are the mitigation strategies for avalanches? ›
Structural measures include diversion structures, dams, retarding structures and starting zone structures design to prevent avalanche initiation. Forest management can also be used to mitigate avalanche hazards.
How can we protect from avalanches? ›
Wear a helmet to help reduce head injuries and create air pockets. Wear an avalanche beacon to help rescuers locate you. Use an avalanche airbag that may help you from being completely buried. Carry a collapsible avalanche probe and a small shovel to help rescue others.
What is the best defense against an avalanche? ›
Avalanche dams
Depending on the speed of the avalanche, dam heights of over 20 metres are required to stop it completely. Diversion dams direct the snow masses to places where they cannot destroy anything. Compared to retaining structures, dams are often the more cost-effective measure.
What are avalanche protection structures? ›
Long-Term Avalanche Protection Structures
Snowpack Support Structures: Engineered rigid structures or nets designed to retain snow and prevent large avalanches by impeding fracture propagation in the snow. These are typically used in inhabited areas or sites with limited evacuation options.
What are 4 mitigation tactics? ›
Let's talk about four different strategies to mitigate risk: avoid, accept, reduce/control, or transfer.
- Avoidance. If a risk presents an unwanted negative consequence, you may be able to completely avoid those consequences. ...
- Acceptance. ...
- Reduction or control. ...
- Transference. ...
- Summary of Risk Mitigation Strategies.
Defensive structures, snow sheds, dams and forestry, closures and explosions as well as spatial planning measures protect settlements and transportation routes from avalanches. We provide expert opinions and advice on a whole variety of such protective measures.
What are the best practices for avalanches? ›
The most efficient way to reduce avalanche risk is to stay on slopes less than 25 degrees. But keep in mind that even if you are on more gentle terrain, avalanches may occur above you or you could set one off by standing on a slab that is connected to the steeper part. Keep an eye on the terrain above and around you!
How can avalanches be controlled? ›
In addition to active avalanche control, we use passive control methods to control snow slides. These include elevated roadways so avalanches pass under them and catchment basins to stop the avalanche before snow reaches the highway. we also use diversion dams and snow berms to keep the snow off the highway.
How can you reduce the risk of an avalanche? ›
By waiting at least 36 hours after a big snow or wind storm before you go into the mountains will allow for the snow to become more stable and less likely to avalanche. If you stay in valleys away from avalanche chutes, in stands of trees, or on gentle slopes you can decrease the risk of being caught in an avalanche.
People caught in avalanches can die from suffocation, trauma, or hypothermia.
What to do if an avalanche is coming at you? ›
If an avalanche is coming towards you, ride away as quickly as you can towards to the side of the avalanche path. 9. As the flow starts to slow, try to create an airspace by clearing snow in front of your mouth with one hand while reaching to the surface with the other.
What not to do during an avalanche? ›
Don't ski with your pole straps wrapped around your wrists. Poles can act as anchors in an avalanche and make it harder to stay on top of the snow. NOAA guidelines also recommend you never try to outrun an avalanche. Try getting to the side as quickly as possible, out of the path of the oncoming snow.
How do people protect themselves from avalanches? ›
Wear a helmet to help reduce head injuries and an avalanche beacon to help others locate you. create air pockets to give you more space to breathe and help you from being completely buried.
What are the strategies for avalanche control? ›
Techniques Used in Avalanche Control:
Control Techniques: Triggering Avalanches: Controlled detonations or artillery fire are used to trigger smaller, controlled avalanches in a controlled environment. This reduces the buildup of unstable snowpack, minimizing the risk of larger, uncontrolled avalanches.
What is in an avalanche safety kit? ›
These kits will contain all the tools required to figure out exactly what is going on inside the snowpack. Basic items in a snow kit include snow saw, knotted cord, magnifier and crystal card, notebook and a thermometer.
What are the mitigation strategies for disaster? ›
Disaster Mitigation
- Promoting sound land use planning based on known hazards.
- Buying flood insurance to protect your belongings.
- Relocating or elevating structures out of the floodplains.
- Securing shelves and water heaters to nearby walls.
Control Techniques: Triggering Avalanches: Controlled detonations or artillery fire are used to trigger smaller, controlled avalanches in a controlled environment. This reduces the buildup of unstable snowpack, minimizing the risk of larger, uncontrolled avalanches.
What are the key mitigation strategies? ›
We then delved into the five key risk mitigation strategies: acceptance, avoidance, mitigation, reduction, and transfer. Each strategy offers a unique approach to managing risks based on their likelihood and potential impact.
Artificial triggering of avalanches is a widely used cost-effective method for protecting roads, railroads, ski areas and other sites that can be efficiently and completely evacuated, and there is little or no risk of property damage. The use of artificial triggering to protect permanent valuable facilities such as houses is controversial and generally avoided in the United States because of the potential for unintended consequences and acceptance of responsibility for damages. 
