Eldorado Peak Survey

Eldorado Peak Survey, Klawatti Col Survey, Tyee Crag, Eggplan/Torado Needle

Sept 28, 2024

2am – 8pm

Eric Gilbertson and Ross Wallette

Results: Eldorado Icecap has melted 20ft since 1950 and is no longer the summit. The rocky outcrop 100ft west of icecap is summit at 8873.3ft +/- 0.1ft NGVD29

The rock outcrop likely overtook the icecap summit sometime between 2019 – 2021.

Klawatti Col has melted 18ft since 1963

I’m working on a project to survey peaks in Washington whose elevations and prominences are affected by climate change. These are peaks that have icecaps on the summit or glaciers on tkey key col that could be changing elevation. There are only four peaks with icecaps in the lower 48 states, all in Washington, and I’d previously surveyed three of them – Rainier Columbia Crest, Liberty Cap, and Colfax Peak. The only remaining one to survey was Eldorado Peak.

The accepted time of year to survey icecap summits is at the lowest snow time of year when snow has melted down the most but has not yet started accumulating from autumn snow. In Washington that’s approximately late august through september. The higher summits in Washington still haven’t gotten their first significant autumn snows, so it’s still prime time for surveying these peaks.

There are also a handful of key cols in Washington that have glaciers on them. These are the key cols for Colfax, Liberty Cap, Little Tahoma, Redoubt, and Klawatti. The Klawatti key col is not too far from Eldorado Peak, so I decided to survey both on the same trip.

The standard approach to Eldorado and surrounding peaks is via Cascade River Road, which has been closed due to fires most of the summer. Luckily it had just opened a week earlier, so an Eldorado survey trip was back in the cards. Ross was interested in joining, and we carpooled up Friday night to the Eldorado lot. I brought my big chainsaw but unfortunately there were no trees to clear. I guess I’m used to venturing up that road in winter when there are always fresh blowdowns that need logged out.

We slept a few hours and then were moving by 2am. Ross had just been to the Eldo area in July before the fire, so he led the way to the good log crossing at the start. We then picked up the climbers trail and made good time up to the boulder field. I’d last been here in January on a failed attempt where we had to turn around at the boulderfield. On that trip I’d snowmobiled in 5 miles to the trailhead logging out trees en route. Then we’d taken all day to break trail up to the boulders before bailing. It was so much fast and easier this time!

We crossed over to the Roush Creek drainage then reached the base of the Eldorado Glacier just before sunrise. The glacier was very icy and crevassed and we roped up at the base. We made good time up to the Inspriation Glacier as the sun rose, then crossed to the Eldorado camping area for a break. From there we followed the glacier up the east ridge of Eldo.

Usually the route finishes by ascending the NE ridge to the top of the icecap summit. This is how I had climbed it when I was last there in September 2018. However, this time the icecap summit looked much shorter. In fact, a rocky outcrop on the left actually looked like it was now taller than the icecap! This was way different than in 2018.

So we stayed on the rock-snow interface on climbers left and ascended directly to the rocky outcrop where we unroped and dropped our gear a bit before 9am. It was quite obvious the icecap was no longer the summit of Eldorado. Now the rocky outcrop was the summit.

I quickly took out my 10-arcminute sight level and measured an angular declination to the icecap. Then I went over to the icecap and measured an angular inclination up to the rocky summit. I used my GPS to measure the horizontal distance between, and some quick trigonometry showed the icecap was 8.2ft lower than the rock. This was surprising. It must have melted a lot since 2018 when it had been higher than the rock.

I set my differential GPS tripod up on the highest spot I could next to the summit boulder and started logging data. I measured with a tape measure the top of the rock was 1.2ft above the bottom of my antenna rod. So I would add that on at the end for my final measurement. This way I would get the accurate measurement of the height of the highest point on Eldorado, and I would subtract 8.2ft to get the icecap height.

This is standard procedure in surveying to measure one location of solid rock with with very high accuracy and measure a nearby icecap relative elevation with a sight level. This is in fact how Rainier was surveyed in 1956 when Columbia Crest was the icecap summit and its height was measured using a sight level from the nearby USGS monument on rock.

On the quad there is a triangle benchmark drawn next to 8868 in this rocky summit, but it is not exactly on the summit. It is below and to the west. USGS benchmarks are placed in places that are easy to survey, not necessarily on summits. This has led to a bit of confusion, with people assuming the elevation of Eldorado Peak was 8868ft based on the quad, when it was (and is) in fact higher than that.

We waited around for an hour for the measurement to finish, then packed up and headed down. We descended to below a big set of crevasses, then started traversing north along the Inspiration Glacier. We tried to maintain elevation and stay as high as possible where the crevasses weren’t as numerous.

We made fast progress, though had to weave through some steep icy crevasses below Flower Tower and Tamath Crag. By noon we finally reached Klawatti col and dropped our gear. Interestingly, the quad shows the location of the col just at the base of the southwest ridge of Klawatti. But the glacier appears to have melted a lot since 1963 when the quad measurements were taken.

Now the base of the southwest ridge is a flat rock rib and the larger glacier to the west has melted down lower. So that is the new location of the key col. I mounted the tripod, packed snow around the legs so it wouldn’t overheat and tip over, then started logging data.

Ross went around to take some pictures and I hung out babysitting the device to make sure it kept logging data.

After an hour we packed back up and returned back along the Inspiration glacier following our tracks. We were a bit ahead of our planned schedule, though, and there were plenty of peaks around ripe for bagging. The highest point on Tepeh Towers, Tyee Crag, looked appealing and was just a short detour, so we decided to bag it.

We hadn’t research it at all, so would just have to onsight it. We scoped out the northeast ridge, which looked tricky, then the south face, which also looked tricky. I finally found the southwest ridge looked like the line of least resistance.

We dropped our gear and I tied the rope into a backpack just in case we needed it. We scrambled 3rd class rock directly up from the glacier, then followed easy ledges across to the north face. There the route got a bit tricky. But Ross led the way up a 20ft low 5th class step with rap rings on top.

From there it was exposed 4th class scrambling along a sharp ridge to the summit. We admired the view for a while, and looked around for a register, but didn’t find one. For the return we downclimbed to the rap anchor, then rapped down and returned to our gear.

We then retraced our steps all the way back to the edge of the Eldorado Glacier. One more peak tempted us, though, since we were still ahead of schedule. Torado Needle/Eggplant was just along our route and looked like another easy side trip that would be quick. So we ditched out packs and quickly scrambled up class 2/3 rock to the summit. By then I felt a few drops of rain and the clouds were thickening, so we decided to head back.

We descended back down the Eldorado Glacier and met three people hiking up unroped. It looked like one guy was climbing Eldorado and the other two were doing an overnight trip.

We made good time retracing our route back, and stopped to graze on blueberries on the way. I think the road closure has ensured that the blueberries are still very plentiful up at the edge of treeline.

We made it back to the trailhead in a light rain a bit after dark, and were soon on our way home.

I processed the results at home and found the rock summit is 8873.3 ft +/- 0.1ft (NGVD29), which is 0.5ft taller than the 2022 Lidar measurement of the rock summit. This isn’t too surprising, since Lidar can miss the exact top of a pointy boulder, and stated accuracy is +/-0.4ft in flat terrain anyways. The dGPS measurement is the most trustworthy.

Because the icecap summit is 8.2ft lower, this means the icecap is 8865.1ft, and is no longer the highest point of Eldorado.

None of the old quads show a direct measurement of the icecap summit, just of the benchmark. However, I discovered a picture from late September 1950 taken from the rocky summit looking towards the icecap. I used Edward Earl’s Geopix software with four background peaks identified to measure the top of the icecap was 6.9 +/- 0.3ft above the camera height.

If I assume the camera height is 5.5ft above ground on the rocky summit (for an average person’s height holding camera at eye level), then the icecap was 12.4ft above the rocky summit in 1950. This is the 1950 data point in the plot above, assuming the rocky summit has stayed the same elevation as the 2024 measurement. I’ve also plotted the 2022 Lidar measurement and the 2024 dGPS measurement. Because the icecap height is now 8.2ft below the rock summit, this means it has melted 12.4+8.2 = 20.6ft since 1950. There is uncertainty in the exact camera height above ground, so I would estimate 20.6ft +/-1ft melt of icecap.

More data would be useful, but based on this data it looks like rock overtook the icecap sometime in the past 10 years. Based on my observations in late September 2018 when the icecap was obviously taller, I would narrow this time window to sometime between 2019 – 2021 when the rock summit overtook the icecap summit.

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