In southern Utah, between Moab and Lake Powell, the Colorado River runs through Catarct Canyon. During times of high water in the spring, this canyon`s rapids become bigger and more dangerous than the Grand Canyon. A rafters nightmare is the dreaded "Maytag" this is when the raft enters the hole and the standing wave below is so huge and powerfull, it cancels out the rivers downstream flow and anything that goes into this trp gets stuck there. Eventually it will come out but usually in pieces. With a good life vest, most people get spit out quickly but the gear and the boat are often lost. God help you if you get tangled in any lines. At 1:40 of this video, the worst happens and it is truly nightmareish...
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The big commercial companies use the big J and K rigs. To give you an idea of the size of this water, check out how this huge boat gets tossed.
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This is the Deschutes River that I run all summer.
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