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Massive mudslide in Colorado on Sunday, Memorial Day weekend

The Sunday, May 24, Mesa County Mudslide. Dimensions
are uncertain, but at least 0.5 mile wide, 2-3 miles long, and
250 feet deep. Photo by Aaron Ontiveroz, Denver Post
as published here.Heavy rain again (after Oso and Afghanistan) appears to have triggered a massive mudslide, this time in the Grand Mesa country of Colorado. The location is 11 miles southeast of Collbran, about 40 miles east of Grand Junction. The area is remote, cell coverage is sparce to nonexistent, and news is just starting to break of this event. More than 3/4" of rain hit the area on Sunday. Three men
, locals who had gone into the area to investigate the possibility of a smaller slide when they noticed problems with their irrigation water, are missing.

Location of Collbran ("A") relative to Grand JunctionThis slide (dimensions in figure caption) is significantly larger than the Oso, WA, landslide which measured about 1500 feet wide, 4400 feet long, and 30-70 feet deep. The area is on U.S. Forest Service and private land. No structures or major were involved. The sheriff has reported that the person who reported the slide heard a sound like a freight train, and that "the slide came down with so much force and velocity that it came to a hill and went up and over a hill and then came back down--a significant hill." The area remains unstable as of this writing (2:30 PDT, Monday).

I couldn't find any references to previous slides in this area, but did find a 2013 paper entitled "Characteristics of Landslides in Western Colorado, USA", focused around the Somerset-McClure Pass area only about 50 km away (as the crow flies, a lot longer by any access roads as they are separated by the Grand Mesa National Forest and some rugged country.) The authors of this paper are N.R. Regmi, J.R. Giardino, and J.D. Vitek, and it is published in Landslides, on-line 05 June 2013. The Colorado Geological Survey also has an extensive website and inventory program that can be viewed here. It is painfully clear that western Colorado has major landslide problems.

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