Glen Canyon, Utah. Hiking deep in a side canyon of Glen Canyon at a location 100 feet below the high-water mark of Lake Powell. This and many other side canyons were flooded by the rising waters of Lake Powell when the diversion tunnels around Glen Canyon Dam were screwed shut in 1963. When this image was made in April of 2005, the reservoir was 145 feet below its full-pool elevation with only 32% of its water volume remaining. Two years of above-average snowpack have since raised the level of the reservoir about 60 feet. With increasing demands on the Colorado River, it will take many, many years of above-average snowfall to fill Lake Powell to its normal elevation of 3700 feet above sea level.