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New avalanche ratings based on terrain

Parks Canada expects system to eventually be adopted outside national parks

Parks Canada has rated the general avalanche risk of hundreds of the most popular backcountry ski trips in Canada’s mountain national parks.

The move follows an internal review of backcountry avalanche risk after seven Calgary students were killed in an avalanche while touring with a school group nearly two years ago.

The new avalanche terrain rating system has been used to classify certain types of terrain and formulate policies about what types of groups can use the terrain.

Custodial groups, such as school tours, will no longer be able to use "complex" areas where the terrain is rated high for avalanches between Nov.15 and April 30. If they want to use "challenging" terrain they must be accompanied by a certified mountain guide with a permit. Custodial groups will be able to use those trails that are considered "simple" on their own.

Grant Statham, Parks Canada’s avalanche risk specialist, said the new rating system, called the Avalanche Terrain Exposure Scale, will allow people to use the trails more wisely.

"The idea is that you can measure your ability against the landscape before you are actually standing there," said Statham. "Ultimately it is up to people to make their own decisions out there. We are not preventing people from going anywhere. But what we want to do is give them the best information we can and I think this is a really big step in terms of the information we give to people."

Historically people have only been able to get information about avalanche risk based on snow conditions, which can change from day to day. There has been no way to classify the very terrain the snow is falling on until now.

"This Avalanche Terrain Exposure Scale gives us a way to discuss avalanche terrain with people much more clearly," said Statham. "And avalanche terrain doesn’t change from day to day. So if I say this valley is rated Class 3 (complex) based on the terrain, that is not going to change."

The ATES does not remove the responsibility for backcountry users to check avalanche bulletins for the latest snow conditions whenever they plan to head out.

"They still need to understand how the snow works and that it fluctuates everyday," said Statham.

The information will be available for all four of B.C.’s mountain national parks: Glacier, Kootenay, Mount Revelstoke, and Yoho, as well as the other mountain parks across Canada. For more information checkout the Web sites for any of the parks. For example Glacier Park’s site is at .

The information should be part of any pre-trip planning done by youth leaders or the public before they head out into the parks. The three classifications of terrain are: simple (class 1), challenging (class 2), and complex (class 3).

For simple terrain you don’t need an extensive background in avalanche forecasting, what you need is common sense, the right equipment, first aid skills and the discipline to respect public avalanche warnings. It is ideal territory for novices trying to gain backcountry experience. It is important though to remember class one terrain is not entirely free of avalanche risk.

For challenging terrain groups must know how to recognize and avoid avalanche prone slopes. Many big slopes may exist in this terrain. Those using this terrain must know how to use the avalanche bulletin, perform avalanche self rescue, basic first aid and be confident in the group’s route-finding skills.

If you are unsure of your skills hire a professional guide.

Travelling in complex terrain demands a strong group and is reserved for those with years of critical decision making experience in avalanche terrain. Often there are no safe options in this terrain. As a minimum those in your group should have taken an advanced recreational avalanche course and have several years of backcountry experience.

Statham believes it is only a matter of time before the scale is adopted for use outside the park.

"There are many uses for the scale and as the years go by I think we are going to find more and more ways to use that information," he said. "I have a feeling this will probably spread with time."