Avalanche Areas Below Tree Line

Avalanches and avalanche control have been heavy topics here over the last few weeks, and while today is no exception, now that the storm has passed and the avalanche cycle has mostly run its course, you can expect to find other topics appearing shortly.

In the wake of the storm that left over 60cm of new snow on the mountain, the avalanche forecaster was forced to consider parts of the mountain that normally aren’t a problem with regards to avalanche hazard. While many of the places are in the alpine, there are also a few  that are tucked away in hard-to-find pockets hidden in the woods. While hard to find, they’re still in open terrain, so must be considered when planning the day’s avalanche control. Four of these areas are located on the front side of the mountain – Midstation Pocket to the skier’s right of Men’s Downhill, Ladies’ Pocket to the skier’s right of Ladies’ Downhill, Comer’s below Eagle Meadows cat track, and Paradise Pocket just above Pine Cone Way. These pitches aren’t big enough to attract those looking for untouched powder, but they are big and steep enough to avalanche and do get traffic nonetheless.

Cummer's

Comer's

On Saturday, two of us headed towards Comer’s and Paradise Pocket, since both can be controlled on the same lap. Dropping into Comer’s, there was lots of snow, and it was also apparent that there had been traffic throughout the storm, stabilizing the snow. Ski cuts here did not produce any results. Moving down to Paradise Pocket* the signs of traffic became less and less, and when we arrived at the top of the slope, we were pretty sure we’d get results.

Since the pocket looms directly over Pine Cone Way, we called a patroller to do a spot closure at the top of the run. A spot closure is just a temporary and usually brief closure of a run with a patroller standing guard rather than setting up closure fences and signage. Once the run was secured, we began by putting a ski cut across the top of the slope, which produced an immediate result as most of the feature avalanched the full length of the pitch. The skier’s left 1/3 of the slope did not slide, so I ski cut the top and got all of that to go as well. The debris ran to within a metre or two of Pine Cone Way, so not only were we glad to have closed the run, but also to have controlled the slope and removed any avalanche hazard.

The next photos are of Paradise Pocket before and after the avalanche, and you can see in the first how close the pitch is to Pine Cone Way. And, a short video (0:10) shows the first ski cut getting a good result.

Paradise Pocket - before.

Paradise Pocket - before.

Paradise Pocket - after.

Paradise Pocket - after.

It’s always good to go to places that are seldom visited in the course of a work day – there’s always something to be learned.

*It may seem strange that a pocket on the front side is named after a chair on the back side, but Paradise Pocket was named long before the chair of the same name existed. Perhaps it was named after Paradise Valley by Mt. Temple?

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Avalanche in West Bowl

Despite all the recent news of avalanche fatalities in North America and despite no shortage of warnings of high to extreme avalanche hazard in the backcountry of Banff National Park, two riders found the lure of untracked powder too powerful to resist today just outside the area boundary of the Lake Louise Ski Area.

West Bowl is located immediately west and outside of the Outer Limits boundary fence, and is probably the most travelled area outside the boundary due to ease of access. It can be reached from the top of Outer Limits or through the Window, which accesses the very top of the bowl as you head towards Boomerang.

Below is a diagram that’s posted at the Outer Limits access point to West Bowl:

Parks Canada diagram of West Bowl - © Parks Canada

Parks Canada diagram of West Bowl - © Parks Canada

About mid-afternoon today (which, by the way, was Avalanche Awareness Day at Lake Louise), a patroller working in the Summit area was skiing down Outer Limits, and stopped to look into West Bowl. She saw a startling sight – West Bowl had avalanched, and there was a boarder above the slide climbing back to the top of the ridge, and another in the debris pile trying to dig himself out. The avalanche was reported to our Avalanche Forecaster, who immediately instructed patrol dispatch to contact the Parks Canada warden service to prepare for and assist with a possible rescue, then started to head that way with other members of the avalanche control team.

As I mentioned in a recent post, Lake Louise Ski Patrol will respond to an out-of-bounds rescue, but the avalanche forecaster is the only person who can authorize any staff member to leave the area boundary, and except in very low-hazard conditions, only those patrollers with their Canadian Avalanche Association Level 2 avalanche course certification will be involved in the rescue. The public safety wardens called for a helicopter to assist in the rescue, but once it was confirmed that the two people we observed were the only ones involved in the avalanche and no rescue was required, it was called off. The wardens also stood down and let us do our thing.

A staff member was sent to the Window to intercept the person climbing back to ridge-top, and after ensuring their own safety, two patrollers skied in towards the rider who had by now dug himself out of the debris and was waiting for assistance. It’s possible to ski West Bowl most of the way down and still get back to the bottom of the Summit lift, but the avalanche had carried this one person well below that point, so he and the patrollers skied down the one prominent gully below called Deep Throat and down to the Monkey Trail (aka Star Wars), which is the long forest traverse that returns people to the resort via Juniper Jungle. Once in the avalanche forecaster’s office, they were able to tell their story…

The two were both snowboarders from Calgary in their 20’s, and, deciding to take advantage of the untouched powder, entered West Bowl through the Window. Even in good snow years, you need to pick your way through a few rocks to get down to the actual bowl since the top ridge gets scoured clean by the wind. Once they did so, the first rider decided to do a quick traverse across the top of the slope, but as he did so, he hit a rock that forced him to turn down into the slope. He then decided that since he was on the slope he might as well keep riding. He only managed a few turns when he realised the slope was starting to slide around him. As this realisation sunk in, and before he had a chance to react, the slide suddenly increased in width so that it covered almost two-thirds the width of the bowl – about 250m.

The avalanche slid to ground, and while the snow depth was only about 40cm or so, the depth and width combined to make a large avalanche – a size 2.5, which is enough to bury or kill a person, and typically has a mass of 100 tonnes. The rider was swept up and carried down the slope, and he described being tossed around, alternatively ending up on top of the debris and being completely buried, over and over again. He “fought like crazy” and tried to swim to stay on top, but the avalanche was just too powerful. When it came to a rest about 250m below where it started, the rider was upright and buried up to his chest. He looked up slope to see that his friend had not been caught in the slide, and noticing that there was still snow that had not avalanched, yelled for him to climb back up to the top rather than try to get to him and possibly start another avalanche. He had managed to free himself from the debris by the time patrollers arrived.

As he recounted his story, an hour or more had passed since the incident, and as the adrenaline faded, he broke into tears realizing how lucky he was to be alive. Had he been completely buried, the lack of oxygen would mean he only had about fifteen minutes before brain damage was likely, and his chances of survival would have plummeted. It was lucky that a patroller observed what was going on just after it happened and was able to report it, but even then, getting to the victim in fifteen minutes or less would have been unrealistically optimistic.

Both of these riders had taken avalanche awareness courses in the past, but the message appears not to have sunk in (although there’s no doubt in my mind it has now). Also, as the victim and patrollers arrived at the start of the Monkey Trail, there was a group of eight snowboarders who had just come down Maintenance, another out-of-bounds run near but not quite as big as West Bowl. Not one of them had avalanche rescue gear, and one of them, upon seeing the rider with the patrollers, remarked “Riding alone? What an idiot”. If only he knew… 

The two boarders were asked to come to the avalanche office to tell their stories, because there are always lessons to be learned from an incident like this for both those involved and others as well. No doubt they’ll tell their families and friends about this. They were not punished, since they did nothing wrong from a policy point of view. Our boundary is open, and these two crossed it in a way that contravened no laws or resort regulations. What they did contravene are the protocols for safe travel in avalanche terrain – among others, know the hazard, have and know how to use a beacon, shovel, and probe, tell people where you’re going, and have a plan.

The two left here today with a new attitude about avalanches, and we hope they’ll spread that experience to as many people as they can. Others haven’t been so lucky.


Another Epic Day at the Lake

While the snow may have let up a bit today, the smiles did not as skiers and boarders enjoyed another day of powder turns at Lake Louise. This recent storm, nearing a total of 50cm over the last few days, has added a third to a half of our total snowpack, and with forecasts calling varying amounts over the next three or four days, it doesn’t look like it’s about to stop.

The wind that was absent during the bulk of this storm finally arrived early this morning, and we started to see some of this new snow get moved around. If the wind keeps up, avalanche control teams will have a lot of work ahead of them since wind-deposited snow tends to make the hairiest avalanche conditions with the biggest consequences. By consequences, I mean destructive power. Over the last few days, we’ve been able to get some small loose snow avalanches started in steeper terrain, but these slides didn’t pick up much mass or run all that far. The snow remained loose, so even the avalanche debris made for good skiing.

When wind-blown snow is deposited on leeward slopes, it forms a slab, and this is due to a few things. First, as the wind moves the flakes over the ground, the delicate crystals break into smaller pieces, meaning they can be packed more densely. Also, the wind acts as a packer, pushing the pieces of crystals even closer together. The resulting slab becoms one big piece of snow, meaning that if one section of the slope wants to slide, the rest of the slope is more likely to go with it. The dense chunks of slab have the potential to cause much more damage than a loose snow avalanche, which can flow around objects more easily. Of course, if there’s enough volume, a loose snow avalanche can be very destructive.

30am, Summit

Powder, powder, everywhere...8:30am, Summit.

With all of this new snow and the huge load it has now placed on the underlying snow layers, we will be heli-bombing for about half-an-hour tomorrow morning. I’ll be there, camera and all, and will post all about it in the next day or two (or three).


More Powder at the Lake for Thursday!

When I left Lake Louise last night it was snowing. When I arrived at Lake Louise this morning, it was snowing. It’s snowing now, and it appears we’ve received another 10cm at the base area, with more up top. Once again, there was little to no wind, which means terrain should open quickly (the gates to normally open terrain were all cracked before 10:00am yesterday).

If you were here yesterday, you already know what an epic day it was, with a nice deep layer of light dry powder evenly distributed everywhere. With light crowds, there were fresh lines to enjoy all day long, and by the looks of things, it’ll be that much deeper today.

The first photo below is the “unofficial” snow plot outside my office window at the base area. I cleared it off yesterday morning after I took a similar shot, so all of the accumulated snow is in the last 24 hrs.

Overnight snow (and still falling).

Overnight snow (and still falling).

45am - still snowing.

Thursday morning, 6:45am - still snowing.


Powder Update – Wednesday 10:30am

Back at the computer for a quick post after a great morning of avalanche control and after having visited our weather plot on the back side. As expected, there was no wind-affected snow; in fact, it was light, dry powder, and it continues to come down. There are no lift lines, so this is going to be a great week to get to the Lake and enjoy powder all day long.

Some significant numbers from our Pika plot (as of 10:30am today):

  • 24hr snowfall – 27cm
  • Since 3:00pm yesterday – 19cm

Of course, when it’s snowing, the photography is difficult, and I’m okay with that. The shot below was taken around tree line, where the trees add a little definition to the slope.

Looking up from the bottom of Grizzly Gully.

Looking up from the bottom of Grizzly Gully.


Snow Still Falling !

Woke up in Banff this morning to one or two cm’s of new snow, wondering if the Lake got anywhere near what was forecasted…

Well, it did, and as of 5:00am, we’d received 12cm at our back side weather station. It’s been snowing since, and now there’s about 15cm of new snow at the base, with more up high. The beautiful thing? There wasn’t any wind, which means avalanche control should proceed quickly, and more importantly, the snow will be evenly distributed all over the mountain, making what should be a great day of powder at the Lake.

With the snow forecasted to continue until Monday in some models, things are looking up – way up. The holiday crowds have eased off, and there should lots of great snow to enjoy for the rest of this week.

Happy skiing !

45am view at the office.

6:45am view at the office.

45am.

Base area at 6:45am.


Snowing at the Lake

This could be it! 

It  snowed at Lake Louise all day today, and the snow that has been lurking in the recent long-range forecasts (which are usually suspect) looks like it has arrived. Amounts vary by forecast, but snow-forecast.com (link on the right: “Lake Louise Snow Forecast”) is calling for 30+ cm in the alpine over the next 72 hours or so. If there’s any wind accompanying this snowfall, then you can expect up to double or more of the ‘official’ amount in wind-loaded places.

This morning on avalanche control, with our weather station reporting 4cm in the last 24hrs, we found many places with twice that, all thanks to the wind, which blew strongly enough to move the snow around, but not enough to form dangerous wind slabs. This means that the control teams can move quickly through the terrain and get it all open sooner, as was the case this morning.

Avalanche control team loads Glacier chair at dawn.

Avalanche control team loads Glacier chair at dawn.