The entrance to North Canyon Rapid. The viewer will observe the emerald clarity of the water, not colorado at all; the water is also quite cold, in the mid-40s. This is the effect of Glen Canyon Dam. Historically, the Colorado ran warm and thick red, coloured by the vast erosional forces of its upstream basin. Glen Canyon Dam was built largely as a silt trap for Lake Mead, and itsreservoir (Lake Powell) is filling with silt far, far faster than was hoped. The clear, green water is beautiful, even I can't deny it. Fortunately, we are frequently allowed to see what the river looked like pre-dam, thanks to the common flash flooding of the numerous side canyons. Pictures to come!