Colfax Peak Survey

Colfax Peak Survey

Sept 3, 2024, 5am – 7pm

Josh Spitzberg, Eric Gilbertson, Ross Wallette

Results (NGVD29 datum):

Colfax summit:  9,439.9 ft +/- 0.1ft
Key Col: 8,966.7 ft +/- 0.1ft
Colfax summit is 2.1 ft taller than 2022 Lidar measurement.
Colfax Key Col has melted 16.3 ft since the 2022 Lidar measurement

I’m trying to survey peaks in Washington that have summits or key cols with elevations affected by climate change. This means peaks with an icecap or glacier on the summit or key col. Four peaks in Washington have (or have recently had) icecaps on the summits – Rainier Columbia Crest, Liberty Cap, Colfax, and Eldorado. These are, in fact, the only peaks in the lower 48 states with icecaps on the summits. Colfax also has a glacier on the key col, so it was a high priority for me to measure.

I’d just finished surveying Mt Rainier, and found that Columbia Crest, the traditional icecap summit, had melted down 21.8ft since the last ground survey in 1999. Now the summit of Rainier is a rocky point on the SW Rim at 14,399.6ft. For surveys I use a survey-grade differential GPS unit capable of 0.1ft accuracy.

I was pretty sure based on recent satellite images that the summit and key col of Colfax were still glaciers, but I wanted to measure how much they had changed since the last measurements. Elevations were given on old quads based on photogrammetry and theodolite surveys from 1985 and 1999. There were also Lidar measurements of the summit from 2015 and 2022. A dGPS ground survey is more accurate than these and would also give me another data point to try to see any trends.

The accepted time to survey a peak with an icecap on the summit is in the lowest snow time of year so seasonal snow does not get counted towards the elevation. This is generally late August through early September in Washington. This often coincides with difficult glacier travel conditions as crevasses open up and snow bridges melt. Luckily, my friend Tyler had recently skied in this area near Colfax peak and report the route was passable. I’d previously skied Colfax with Tyler in November 2018, though I hadn’t surveyed it then.

Josh, Ross and I drove up to the Heliotrope Ridge trailhead Monday night. We were moving around 5am Tuesday morning. After a small mixup on the trail we reached the base of the Coleman Glacier and then had some navigation decisions. The base of the glacier was very melted out and icy, and the standard access location was too steep.

We scrambled up and right to access a low-angle section of ice, then roped up and started up. I led the way crossing small crevasses and working up and left until the slope finally eased. We then traversed left until we met up with the standard Coleman-Deming route in a big bowl. We had brought our approach shoes with us in case we would descend a different route, and we ditched our shoes there next to a boot track.

From there we followed the boot track weaving through crevasses up to the Baker-Colfax saddle. Interestingly, we saw two other climbers ascending Colfax. I was kind of surprised since this is not a commonly-climbed peak.

We took a break and by the time we started up they were already descending. It turned out there was a narrow snow bridge to get across the bergshrund. There was just enough room for me to lead up the steep snow face while they descended.

I put in a picket for running protection, then built an ice ax anchor at the top. From there we shortened the rope to walk to up the east summit, where the snow melted away. We unroped there and scrambled around the south side on loose class 2-3 terrain. We then gained the ridge and followed the east ridge to a steep snow slope, and cramponed up to the summit around noon.

There was a big icecap on top, with several rock pinnacles nearby. I verified with my 5x sight level the icecap was indeed the highest point by at least 5ft. I quickly mounted my mini tripod and dGPS on the icecap and started logging data.

We spent the next hour eating snacks and admiring the view. Lincoln peak to the south looked very intimidating. We noticed a few parties climbing the Easton route up Baker. The snow below the Roman Wall was very broken up, with seracs cleaving off down to bedrock.

After an hour I logged the data, then we retraced our route to the col, simul downclimbing the steep snow face above the bergschrund.

The key col location was a bit more difficult to identify. The location is defined as the lowest point on the highest ridgewalk from Colfax to Baker. This area was heavily crevassed and we built an anchor to belay me over to the approximate spot. But then I noticed I was in the wrong spot. It was a bit complicated dealing with the rope but we eventually all got over to the true key col location. That spot was less crevassed and melted to bare glacier ice so it was safe to unrope.

I first verified with my sight level we were at the key col, then I set up the dGPS again.

By 3pm the one hour measurement was finished, and we packed up and headed back down. The descent was easier following our up tracks, but it got more difficult when we reached the melted out glacier ice. Our ascent route would be a bit sketchy downclimbing the steep ice, so to descend we headed down and climbers right toward Gargoyle Rocks.

There we found lower-angle ice and made it to the base of the glacier. We then scrambled down to the climbers trail and hiked back to the trailhead by 7pm.

After waiting 24 hours I processed the results with OPUS, the online tool provided by NOAA for surveyors. I found Colfax Summit is 9,439.9 ft +/- 0.1ft, which is 2.1 ft taller than the last measurement, a Lidar pass in 2022. The Colfax Key Col is 8,966.7 ft +/- 0.1 ft, which is 16.3 ft shorter than the 2022 Lidar measurement. This means the col has melted a lot in the last two years!

 

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