|What Is The Highest Peak In The Chilliwack Valley? #1147|
Back To Discussion List Written: 2004.04.19 by: Drew Brayshaw
This is actually a tricky question.
There are three contenders of approximately 8000'. Welch, American Border Pk. and Slesse.
The issue is complicated by the border. Peaks south of the border are surveyed by the USGS while peaks north of the border are surveyed by Canadians, either the provincial or federal surveys.
In previous days ABP was surveyed at 8026'/2446m by the USGS. Going by federal NTS maps, Welch was 8000'/2439m, and Slesse was 7800'/2375m.
However, more recent surveys by the USGS dropped ABP to 7994'/2437m. Meanwhile, Canadian surveys put Slesse, first at "2425 +/-"m (federal), then apparently at 2429m (TRIM). Meanwhile, Fred Beckey upgraded Slesse in the Cascade Alpine Guide to 2439m/8002'.
Meanwhile Welch has dropped to 2431m on TRIM.
I asked Fred about this since he's the confirmed authority on the North Cascades and made first ascents of routes on both ABP and Slesse. He has promised to track down his sources for me but indicated he believes that Slesse is higher than ABP and that his guidebook figures are correct. Another interesting point to come out of this is that the TRIM elevation for Slesse is not located on the actual summit, apparently.
Since I'm responsible for this area in Bivouac by virtue of being the mini-guidebook editor, I have a vested interest in determining the correct elevations. For the moment I have gone with Fred's version of the Slesse height. As an American I would have expected him to claim ABP was higher but apparently not.
One possibility for all of this is that Welch and ABP are both composed of very crumbly rock. It is possible erosion may be lowering their heights - although if this continued at the rate indicated by the interval between surveys, the peaks would vanish within a few hundred years ;)