On request, I have decided to post a TR of my trip to Primus 3 years ago. This TR could not be shortened because it is not a short trip. My memory has faded some, so I'll only include those details which I'm sure about. The photos are pretty bad, so my apologies in advance.
We left Colonial Cr. CG at about 6AM after car camping the previous night. The trail cuts through some swampy, sandy areas straight out of Diablo Lake and gently rises up through the forest where you begin to get some pretty nice views of the N. side of the Primus summit block. The trail here is well maintained, but gains very little elevation until you get to Thunder Ridge.
You cross Thunder Creek at ~6 (I can’t remember the exact mileage) miles in via a little bridge. Get lots of water here because it's a long way up Thunder Ridge to the Borealis Glacier, and there is no water for 4000 very steep vertical feet. Once you cross the bridge you head off to climber’s right then traverse around the base of Thunder Ridge about 200 meters until you find a faint climbers path heading straight up the hillside. The trail is quite steep, and if it's muddy you would definitely need crampons -- I suggest going on a dry day.
Stay on the ridge, angling very slightly to climber's left if anything (you do not want to go to the right and end up in the McAllister Creek drainage .. pay particular attention here if you plan on coming back out the same way -- it is VERY confusing upon descent). After about 1000' vert. of grabbing branches and twigs, the trees start growing quite close together, and you lose the "path" (which is hardly a path to begin with). In places, we had to actually remove our packs. If you like pine needles, this is your zone ... I'm still picking them out of my LaFuma 3 years later.
There are a lot of cliffs on either side of the ridge, and in places it's not feasible to stay exactly on the ridge, and with the density of the trees, it's hard to see where you need to go. We found it easiest to traverse climber's left under all cliffs we encountered on the ascent.
At about 4835' (appr.) there's a nice little bench situated in a clearing where you can get a nice picture of the remainder of the route up to the Borealis. Up until this point, we were totally blind and going strictly off the topo. Remember this bench if you descend this way and shoot right for it, because you will definitely need to make use of it to find your way down. It is very easy to get cliffed in on Thunder Ridge. I cannot stress this enough, and I’m surprised no other trip reports that I’ve read make mention of this.
From 4835 it's a easily navigable but steep (and for us HOT) slog up to camp at ~5600'. From camp, there are excellent views of Jack Mountain to the North and Primus and Tricouni and the beautiful Borealis Glacier to the South.
The following morning we made the short climb to the base of the Borealis Glacier and roped up. From here, you could either climb the North Ridge of Tricouni, or head up the Borealis. Since we were intending on doing the entire traverse, we opted to climb the glacier since it appeared much faster. In August of 2000 the upper glacier was quite broken up (sorry I don't have a pic of the upper Borealis) and we found it interesting gaining the upper glacier. The crevasses are quite large on the upper Borealis, and we were forced to climb down through some of them. We found a sketchy route straight up the center of the glacier through a rock band. Later on upon descent we found that the W. Side of the glacier offered the easiest route. Once you gain the upper Borealis it's cake. Ascend to Lucky Pass, where the views of the Cascade Pass area are the best there are. Make the walk to the summit of Primus (about as big as a football field), take plenty of photos of Austera Ridge and Klawatti Lake, and go back down and tag Tricouni. From Lucky Pass we tagged both summits in about 3 hours round trip.
Unfortunately, this is where we stopped. It was already about 3PM on day 2 and my party was not up for doing the rest of the traverse as two of them had obligations early on the 5th day (we gave ourselves 4 days for the entire traverse, including planned ascents of Austera, Klawatti, Eldorado, and of course Primus and Tricouni).
This is the most beautiful place I've yet been in the Cascades. Borealis Glacier is awesome, and once you get to Lucky Pass, you are a long ways away from civilization.
The descent was VERY tricky. We managed to stay on track most of the way, but we took 2 minor detours when we got temporarily cliffed in. Pay particular attention to cliffs .. they are everywhere, and often times they are very close together. In places there is only one feasible route between cliffs without making a double rope rappell.
By the time we got to the bridge near the intersection of McAllister and Thunder Creeks, it was already 7:30PM. The rest of my party decided they had enough, and couldn't make the last 6 miles to the car that night. Everyone had horrible blisters from the 6500' descent through VERY steep terrain. I was so dehydrated I couldn't drink. I figured if I stopped there, my blisters (which were already bleeding) would prevent me from moving the following morning. At this point I just kept on strolling along and headed back towards Colonial Creek campground. At about 2.5 miles from the car, I could no longer walk on the flats of my feet. I had to walk on the sides of my feet because my blisters were so severe. I was so thirsty I stopped to drink in a creek (no filter, and no iodine) at about 1400'. I was so tired, so thirsty, so sore, and my blisters hurt so bad that I couldn't stop for more than a minute at a time for fear that I wouldn't get going again. I literally crawled on my hands and knees the last half mile to the car. I have never been so physically drained in all my life, and was sick and couldn’t walk for almost two weeks afterwards.
Overall, it was an awesome trip. I wouldn't wish the descent down Thunder Ridge upon anyone, but if you plan on going out the Eldorado side, I would consider it an ideal Cascade traverse .. and one that seldom gets done.
The view to Primus from the approach :
http://mywebpages.comcast.net/sjolseth/004_6.BMP
The view to Ruby Mountain from camp :
http://mywebpages.comcast.net/sjolseth/007_9.BMP
Looking back down the Borealis Glacier :
http://mywebpages.comcast.net/sjolseth/014_16.BMP
Me on Lucky Pass :
http://mywebpages.comcast.net/sjolseth/015_17.BMP
Klawatti Lake and Cascade Pass area from Lucky Pass :
http://mywebpages.comcast.net/sjolseth/026_28.BMP
Primus Peak from Tricouni Peak :
http://mywebpages.comcast.net/sjolseth/027_29.BMP
EDIT:
A partial view of the upper Borealis .. if you can get past the glare of that pink shirt!
http://mywebpages.comcast.net/sjolseth/011_13.BMP
I can't get these photos to show up in the body of this post (they are bitmaps), so I made them into links.
