The Lake Blanche Trail to Sundial Peak is the most popular hike in the Central Wasatch. Every summer, thousands of people ascend to the crystal waters of Lake Blanche near the top of Mill B South Fork in Big Cottonwood Canyon. But in winter, upper Mill B South Fork is empty. Sure, the backcountry skiing around Sundial Peak can be good, but it’s hard to get to compared with off-the-road descents that see much more traffic. This distinct lack of people makes Mill B South Fork an ideal spot to find solitude for a little ski touring, and even winter camping, on the shores of Lake Blanche.
Mill B South Fork has a lot of quality ski lines, but you have to either skin up the Lake Blanche Trail from its start below the “S-Curves” in Big Cottonwood, or access the area from Little Cottonwood via Cardiac Ridge while bypassing Mineral Fork. Once in the upper cirque, take your pick of highly advanced skiing on open bowls, chutes and very rocky terrain.
Perhaps the lack of visitors in Mill B South Fork is also due to highly variable snow conditions. The upper canyon is gigantic; three separate cirques spread out below the north face of Monte Cristo and the east side of Dromedary Peak. Exposure is high here, which means the snow is either sun crusted or wind scoured. It’s a lucky backcountry skier who arrives in Mill B South Fork and finds excellent snow. But new snowfall simply creates avalanche danger, and the upper cirques have plenty of that. Hangfire lives everywhere beneath cliffs and rock bands that pepper the slopes in all directions, with frightening avalanche crowns dozens of feet deep.
The exit in Mill B South Fork is also a deterrent, where a thin, icy trail winds through scrub oak, aspens and brush. Descending this can be challenging (especially while wearing a heavy pack,) and thigh burning. Your quads will hate you the next morning.
But all is not lost around Lake Blanche. If avy danger is high, mellow and safe terrain can be skied on the benches below the cirques and Sundial Peak. Rolling hills and tree-protected powder shots spill down to the frozen lake’s edge – perfect for lapping short vertical after a long morning of just getting there. There’s also sweet skiing off the ridges below Lake Blanche, especially on east-facing slopes where avalanche paths have cut ski-run style swaths through the pine forests.
If the skiing is questionable, scenery and solitude alone is reason enough to make a tour into Mill B South Fork. Sundial Peak is the main attraction as it shoots up from snowfields above three alpine lakes, surrounded by some of the most beautiful peaks in the Wasatch. A group can spend a mellow time checking out the terrain, eating lunch, or even staying the night.
Winter camping is also ideal in Mill B South Fork, where you can dig out a base camp in the snow and spend a few days skiing slopes that rarely see any tracks. The pine forest between Sundial and Lake Blanche is a wind-protected, flat spot that’s a perfect place to pitch a tent and practice your winter camping skills.
So if you want to experience the most popular hike in the Wasatch, but have it all to yourself, stick skins to skis and tour on up Mill B South Fork to Lake Blanche. You’ll get all the scenery without the crowds, and have the extra bonus of skiing down when you’re done. Definitely can’t do that in the summer.
To get to Mill B South Fork, drive 4.4 miles up Big Cottonwood Canyon to the Mill B South Fork Picnic Ground. Follow the trail all the way up to Lake Blanche, where you can choose from a plethora of skiing options. A secondary way to get there is via Cardiac Ridge. Park at Alta and skin up Cardiff Pass. Follow the ridge west and descend into Cardiff Fork. From here, skin up to Cardiac Ridge where Mineral Fork and Mill B South Fork is easily accessed. Most skiers use this route as a bi-canyon tour and not so much to make laps around Sundial Peak.
As always, bring a beacon, probe, shovel and a buddy when venturing into the backcountry, and go with a knowledge of avalanche safety. Mill B South Fork is dangerous avalanche terrain and can be deadly during unstable snowpack conditions. Check the Utah Avalanche Center’s daily report before heading out.