It’s steep, it’s sustained, it’s gnarly… it’s the Avalanche NW Couloir. Otherwise known as the “Vent Shaft”, this ski-mountaineering classic is a beast of a line that requires crossing a deep bergschrund, scaling a 50°+ slope and skiing a convoluted couloir. The technicality of the route is easier to swallow when considering the easy access with no more than 10km of distance. In our case, we opted for a mini traverse from the NRC (Mortar) parking to the Illecillewaet parking. We gained the Avalanche North Glacier, then the couloir, through the NRC Col (next to the Macdonald West Shoulder). Next thing you know, we’re center-punching the line, exiting through the uber-vast Kors-Thomas Bowl into one of my favourite runs, Avalanche Crest. The intense March sun, baking the south-facing slopes, gave us a glimpse of spring as we skied some quality corn snow. All in all, the Avalanche NW Couloir took us for an unforgettable ride through a variety of terrain from steep, narrow couloir to featured, alpine slopes. A true Rogers Pass classic in my opinion!

Related: Ross Peak Southeast Couloir: Steeps and Bare Ice

Report from March 12, 2021

George, Freddy, Renaud and I arrived at the NRC (Mortar) parking lot at a reasonable 7:30 AM. With an all-time weather window and excellent snowpack stability, this was the perfect opportunity to claim yet another BIG line. After four days of non-stop action, I was properly exhausted but this was too good to pass. So, we toured up the NRC Gully, in the shadow of the Macdonald West Shoulder, an uber-popular ski touring area. The high cloud cover kept the well-trodden uptrack cold, icy, and very slippery which made our ascent tricky. Fortunately, as we arrived at the base of the NRC Bowl, the snow quality improved. After all, it never sees the sun, hence never experienced any spring freeze-thaw cycle, the bane of an established uptrack.

We passed a party of two that was racing us to the Avalanche NW Couloir. Fortunately for us (and sadly for them), one of the guys succumbed to some terrible foot pain; the party turned back. Ski boot pain is a terrible predicament. We pressed on towards the steep slope below NRC Col. Freddy activated his turbocharger, steaming ahead on an existing uptrack. The climb weaved through cliffs exposing us to the overhead slope, typically battered by the harsh alpine winds. With our window of good stability, we deemed it safe. Otherwise, I’d rather head up the Macdonald West Shoulder and perform a high traverse towards the col. Really, if stability was so-so, I wouldn’t attempt the couloir in the first place.

By 10 AM, we gained the NRC Col under cool, blowing winds. After assessing the cornice hazard, we cut across the east flank which linked us with the base of the Avalanche North Glacier, a moderately-crevassed sheet of ice and snow. We ascended the glacier to the climber’s right in order to avoid the crevasse fields and giant seracs to our left.

It was now mid-March. Our fat, alpine snowpack of more than 320cm of snow had filled in most of the crevasses. Since the wind slabs from the steep, lee slope under which ascended posed a bigger hazard, we did not rope up for glacier travel. The climb was steep and sustained, gaining vertical at a breakneck pace, especially when trying to keep up with Freddy. I was wrecked from four days of difficult missions but I pushed through. My mental fortitude was being tested.

After much effort, we gained the upper, flatter part of the glacier, out of harm’s way. The Avalanche NW Couloir could be seen in the distance, rising high in the sky. Impressive but scary line! We all knew what we were getting ourselves into. I lead the group towards a ramp that connected with the couloir’s midsection. The bergschrund, open in summer, was completely filled in. We couldn’t tell the crevasse from the surrounding slope. In the early season, this would be a different story. As an extra precaution, I probed a few times in the vicinity to verify what I couldn’t see.

After strapping our skis to our packs and grabbing our crampons and ice axe, we proceeded up the 45-55° slope to a small col (2812m) between the twin peaks of Avalanche Mt. The bootpack was rather short, roughly 100m of vertical gain. However, it was super steep to the point where my buried ice axe was keeping me from falling backwards. That’s how you know it’s steep. Fortunately, the snow was wind-packed which provided us with a firm base to kick in.

It took us less than 30 minutes to reach the small col, barely wide enough to have all four of us transition side-by-side. For the first time since we departed from the NRC parking lot, the sun poked out of the clouds and illuminated the Avalanche Glacier and the Illecillewaet Valley. My jaw dropped in awe. I’d never seen the Sir Donald range from this angle. Such a beauty! I thought about the Sir Donald to Macdonald Traverse I had completed three days prior. Our route took us through the glaciers surrounding Avalanche Mt. After a short break, we transitioned for the descent and skied down the couloir. My butt was literally scrapping against the steep upper section of the slope. Spicy! Luckily, the snow held an edge, making our jump turns a little smoother.

We all gathered on a sheltered bench, just above the bergschrund. After catching our breath, we skied down the second half of the couloir, the true “Vent Shaft”. While the snow had been tossed up by previous skiers, the 4m-wide choke was in pretty good shape, even after all the sluff had torn through. Spires of rimed snow plastered the side of the couloir resulting in a rather striking sight.

We burst out of the couloir, racing down the open expanse of the Kors/Thomas Bowl. The SW slope had only begun to warm up and still contained some blower powder. We worked the micro-features to maximize our time spent on preserved snow and traversed under the Avalanche SW Ridge towards the Avalanche Crest run.

Avalanche Crest is one of my favourite Rogers Pass runs. By noon, it had been baked by the spring sun for an hour, transforming its usual blower snow into slushy corn. We all revelled in the heat after the cold, blustery walk up the north aspects. We traversed across the slope and skied down the skier’s left slide path, jumping over glide cracks. Within minutes, we had reached the rumbling motors of the Trans-Canada Highway. After a post-holing walk along the plowed snow bank, we arrived at the Illecillewaet parking lot, where cold beers were waiting for us. We were stoked to have checked off another line on our bucket list.

Route Info

6-7 h	1500m	8.6 km	1200-2810 m