Bob Bolton - Mar 11, 2004 11:48 pm - Hasn't voted
7800+ feet of reliefThe relief around Lake Chelan is amazing - cool shot!
Klenke - Mar 12, 2004 1:45 am - Hasn't voted
Re: 7800+ feet of reliefThanks. Of course, the relief was 1,000+ feet greater before glaciation dammed the valley at the end of the lake (thus forming the lake). A glacier lobe extending down the Columbia River east of Chelan plus the deposition of a moraine by the glacier in the Lake Chelan valley both contributed to the damming. In fact, during one of the Ice Ages, backed up water flowed out of Knapp and Navarre Coulees.
Bob Bolton - Mar 12, 2004 11:06 am - Hasn't voted
Re: 7800+ feet of reliefI don't know where the deepest point of the lake is, but it's 1500 feet deep somewhere. That would make the total relief about 9300 feet!
Klenke - Mar 12, 2004 2:18 pm - Hasn't voted
Re: 7800+ feet of reliefActually, I think I got my info wrong (or left out a few details). Yes, the lake is 1,500 ft deep and its bottom is ~400 feet below sea level at its lowest point, which I believe is near Point No Point (about 10 miles down-lake from Lucerne). Also, the dam built at Chelan in 1927 raised the lake level 21 feet.
The depth of the lake was caused by glacier scouring. Before the first glaciers scoured the valley bottom, it was higher than present. The Columbia River, itself I think diverted from Grand Coulee to its present course by natural forces, runs past Chelan at an elevation of ~700 feet. Ergo, the bottom of Lake Chelan's valley before it was a lake would have had to be at least this high, else water would have flowed into it not out of it.
So, basically, what I'm saying is the vertical relief from Copper's summit to the Lake Chelan valley floor before there was a lake there could never have been as great as 9,300 feet and was likely about what it is now. For as the glacier receded up the valley, a lake (Lake Chelan) formed in front of it (or at least that is my supposition).
Blah blah blah.
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