Full Article Here
From the article:
From the article:
Full Article HereDecember 3 to 7, 2016 will mark fifty years since a giant flood roared down Crystal Creek (and many others) in the Grand Canyon. Nothing like it has been observed ever since and as we mark this historic anniversary, I thought it would be nice to set the record straight on what is known and what is not known about this great flood. We all know that Crystal Creek Rapid was enlarged to become one of the “big three” rapids in Grand Canyon. But through the years, enough rounds of “telephone” regarding the dimensions of the flood, what was affected, and how much water was involved, have perhaps obscured what really happened. Data for this flood comes from USGS Professional Paper 980, published in 1977 by Maurice Cooley, B. N. Aldridge, and Robert Euler (Euler contributed results regarding the effects of the flood on archaeological resources).
The storm that produced the flood was regional in scope and affected all of southwestern Utah, southern Nevada, northern Arizona, and southeastern California. Each of these four states saw major flooding and although the North Rim area received the most precipitation at Grand Canyon, not all of the drainages between Saddle Canyon and Deer Creek felt the brunt of this powerful storm. The South Rim also did not receive as much precipitation, just ten miles to the south. At the time of the storm, there was very little snowpack on the North Rim. There was zero snow on the ground at both Grand Canyon Village and at Jacob Lake, and only an estimated 4 to 6 inches blanketed the ground on the North Rim in early December and only a trace of snow fell during the storm. The last significant precipitation before the December event was on November 8 and 9, 1966 and it can be inferred that at the time of the big rain, the ground was moist but not completely saturated.