TR & Avi Report - Wedgemount Lake, Rethel Couloir - Feb 16-17, 2013
Disclaimer - this TR gets super wordy – there are definitely places where my decision making will be judged but I’m sharing as its got a bunch of info about the avi conditions from this past weekend and I think there is a lesson for all.
The avi forecast for the Sea to Sky Area was moderate-low-low and Whistler/Blackcomb was low-low-low, so our group headed to the Wedgemount Lake area to chase after the great North facing couloirs in the area.
The forecast for Saturday was garbage so we chose to take the summer trail (opposed to descending from Blackcomb) as we were certain we could navigate to the hut in any visibility. We were skins on and on our way from the parking lot (just off the highway, road up to trailhead requires tracks or 4 wheel drive with serious tires). The trail was certainly a slog and not a whole lot of fun but it wasn’t actually as bad as we’d expected. Travel through the forest was a pain but the trail wasn’t iced up and generally the snow stuck really well allowing us to do silly steep skinning as required. At the top of the scree chute just before the lake there was some challenging skinning as we fought with dust on crust.
Splitz, Hummus and I made it to the hut in about 4hrs; 45 minutes later Neuro showed up with the three from his car group. Visibility had been in and out all day but when there was a break we split in different directions.
Myself, Hummus and Splitz headed towards Rethel Couloir. Plan was to boot pack up the couloir with hopes of topping out. As we neared the couloir we lost our little bit of visibility but confident in the conditions we proceeded in very low vis. On the boot pack we noticed significant wind loading and were excited about the high quality of skiing awaiting us. Large amounts of sluff were coming down the couloir as snow was blown into it from the top and the cliffs on both sides however the sluff was not enough to pose a serious concern. While leading the bootpack you could notice small ~20cm deep slabs breaking off between your legs and dropping onto the bootpack behind you. Splitz decided to drop early (~2/3 of the way up the couloir) siting concerns about his energy and mentioning that he wasn't entirely confident in the snowpack.
Hummus pushed on while I watched Splitz drop in. By the time I began up again I could barely follow Hummus because sluff had filled his boot-pack so I had to re-punch the boot-pack. The amount of sluff increased making it necessary to climb on the side of the couloir instead of right up the middle where the sluff was being funneled. By this point the grade of the couloir was approaching 50 degrees.
Hummus reached the top while I was still about 50m back. We had hoped to take the commonly utilized ramp to get around the massive cornice (ramp is to climbers right of the cornice). However, the grade increased and the ramp was covered in sugary snow with rock underneath. Hummus began building a launch platform while I finished the climb. The launch platform was just below the cornice with about 55 degree grade. The launch pad was pretty impressive, even though it was only about 2’ wide, our heads were in line with the slope above it which gives an indication of the steepness at this point.
Hummus’s photos:
Hummus look back at me climbing the last section
https://lh5.googleusercontent.com/-C...0/P1080259.JPG
Cornice – not insignificant
https://lh6.googleusercontent.com/-v...0/P1080267.JPG
Hummus standing on our launching platform – notice the slope behind his right shoulder
https://lh3.googleusercontent.com/-F...0/P1080289.JPG
Even a bit of blue sky at the top
https://lh4.googleusercontent.com/-5...0/P1080272.JPG
Hummus dropped in and skied the first section of the couloir with a lot of flow and aggression; I was impressed by the way he attacked the couloir and managed his sluff. I glanced away as he was just leaving my sight and then I heard him yell up and looked down to see he was still at the edge of my sight. He told me to be careful as a slab had just let go that he skied out of. Several minutes later I had my gear ready to go and dropped in. The snow quality felt good with no major problems just lots of fast running sluff. As soon as I got to the point where he had yelled up everything changed. Suddenly the couloir was stripped down to crust although soft spots could be found on the sides. I skied the remainder of the couloir scared that Hummus would not be standing when I got to the bottom. I dabbled in the soft snow at the sides but generally stayed to the stripped couloir.
I got to the bottom to find Hummus a bit spooked but in good shape. The avalanche triggered just above him but he was at the edge of it and skied out of it. Visibility was low so he was unaware of the extent of the slide until he skied it. From where the ~20-30cm slab broke off the entire couloir slid to the bottom (~400m from release to bottom of debris field). As a result of vis we never got a great view of the damage but from skiing it I can say that the slab did propagate outwards as the couloir widened around rock features on the way down. The debris field went almost all the way to the lake. I would say this was a class 2 avalanche.
This is the closest I've been to a serious avalanche incident and feel extraordinarily lucky that no one in my party was hurt or killed; had Hummus been caught in the slide he would have been in for a very long ride – with the way the debris spread out over the fan of the couloir I doubt he could have been fully buried but a 400m ride a 40-50 degree couloir certainly would have left him in bad shape. I can’t help but play out the narrowly avoided scenario of skiing down to find him severely injured and feeling helpless and I wouldn’t be able to do much but dig through his pack to pull out his personal located beacon and call for help.
In hindsight there were several clear indicators that we ignored. These factors were:
- during our final approach up to the hut we noticed dust on crust where the dust was not bonding to the crust at all making for difficult skinning conditions
- significant wind loading in the couloir
- small slabs breaking off between our legs as we hiked
- poor visibility (limiting ability to asses hazard and increasing the consequence of an incident)
We’d been the first 7 to arrive at the hut and assumed no one else would want to subject themselves to that punishment. By the time we were back from afternoon skiing another party of three had arrived and two more arrived after dark (although one of them slept outside). This all lead to a very uncomfortable and cramped night (6 ppl sleeping upstairs which is 2x 4’x8’ sheets of plywood is tight).
The plan for the next day had been to ski other slopes on similar aspects (Wedge NW and Parkhurst N Couloir) however we scrapped these plans as a result of our incident and went in search of other aspects.
Visibility was great and Neuro joined us today in hopes of finding some interesting lines. We set off, leaving the hut at about 8:15 thinking that we’d take a look at Eureka couloir to see if its more westerly aspect could inspire confidence. We ended up on the South Arm of Weart looking down an appetizing East face which lead to Eureka. We cut off a cornice and dropped it on the slope to test its stability (ie. Backcountry bomb). The slope seemed stable and we dropped in for a couple great steep Super-G turns.
Photos from Neuro:
Hummus and I cutting off the cornice
https://lh4.googleusercontent.com/-l...dgmount-18.jpg
Splitz drops in
https://lh5.googleusercontent.com/-K...dgmount-20.jpg
Hummus drops in
https://lh5.googleusercontent.com/-r...dgmount-22.jpg
We skied the upper, steep part of the face and stopped having decided that getting to Eureka would mean committing to a very late return. We skinned back up the face we skied and headed to a mellow South facing couloir that we’d scoped earlier between Weart and Lesser Weart.
By early afternoon we found ourselves climbing the large mellow South facing couloir between Weart and Lesser Weart. As we skinned up 35 degree slopes on the fan we encountered graupel at the surface but continued climbing as it was only on the surface. After climbing another 75m we decided to dig a quick pit, the group was located in two group of two separated by about 40m. I was in the lower group. I pulled out my shovel and quickly determined that a pit was not required to tell the slope was not safe. From the top down there was about 10" of consolidated new (or wind transferred) snow followed by a 1.5" hard ice layer and then absolute sugar for a significant depth. Simply striking the shovel through the layers and pulling it away revealed the layers as the sugar poured out from under the snow.
Neuro’s photos:
You can see the sugar so light as it’s flying from me swinging my hand through it
https://lh6.googleusercontent.com/-b...dgmount-24.jpg
Very clear three layers – new/wind transported snow - ice crust - sugar
https://lh6.googleusercontent.com/-g...dgmount-26.jpg
