Just did the Bow Lake to Emerald Lake Traverse via Emerald Pass (April 12-13) with Simon Robbins. After a late start due to van issues and vehicle shuttling, we managed to leave Bow Lake at 11am on Thursday. A fast skate ski across the lake was followed by a sweltering slog up to Bow Hut where we had some tea and soup. We had blue sky offering great views as we crossed the Wapta through the Gordon - Rhonda Col. We roped up for the short crevassed climb past Mt Collie (the only section of the traverse we donned the rope for) then descended the Des Poilus Headwall on grabby breakable sun crust to the Des Poilus Glacier which we double-poled to the toe. We set up camp in the moraines at the toe of the Des Poilus Glacier at 6pm.
The weather made an about face that night with the blue skies changing to grey overcast sky and light snow. We woke at 6:30am and departed by 8am for Isolated Col. We worked up the ramp to the col (9:15am) in a whiteout then descended the other side into Little Yoho Valley. We avoided the wind scoops in the gully by cutting skiers left over a rib and into the next gully east. At treeline, we maintained our elevation and contoured skiers right through trees to gain the head of the valley. From here we worked up moraines and a narrow draw to the small glacier on the north side of Emerald Pass (12:30pm). The descent of the other side into Emerald Basin looked big, complicated and exposed. We were glad for the overcast sky which minimize the overhead hazards. If it was sunny, we would have bailed and had to ski out Little Yoho Pass which would have reached Emerald Lake by a safer option.
This is a frightening place that I doubt I ever want to ski again. Tons of exposure to overhead hazards like cornices, multiple converging avi paths, cliffs, etc. Of the 1200m vertical, we experienced breakable sun crust on the upper 400m, rock-hard melt-freeze crust in the middle 400m and piles of avi debris on the lower 400m. I didn't take a single photo of this section because we were focused on getting out of there. Nothing like a big terrifying place to make you feel really small. A friend who had done it the week before quipped, "might as well turn your beacon off and put it in the pack cause it ain't going to help in there". It might have been scary but at least the skiing was really bad....
Weather: Yesterday was blue sky and -7C on the Wapta (@ the Gordon-Rhonda Col) @ 2:30pm. Started snowing around mid-night, with 3cm of HST at our camp near the toe of the Des Poilus Glacier. Moderate SW winds both days. Overcast ceiling hovering around 2900m today.
Avalanche Activity: none observed.
Snowpack: HS on the Wapta and Emerald glaciers was 230+ cm. A variety of surfaces ranging from wind pressed defrags on the flats; boilerplate sun / melt-freeze crust on south aspects and wind deposited powder (up to 10cm) on north aspects.
Ski Quality / Travel Conditions: We had absolutely no good skiing. Breakable sun crust on south aspects above treeline. (ie - all of our descents; down the Des Poilus Headwall, Isolated Col and Emerald Basin). However, we skinned up some nice dry powder on the north slope of Isolated Col which would have been good skiing if we were going the other direction. Travel was fast with ski pen ranging from 0 to 5cm. We did not need ski crampons. The crust was mature and supportable in the valley bottoms.