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Show The Colorado Highway Department has been fighting this large slide nearly every winter since U. S. 6 was constructed under this mountain. During times of large avalanches, it is not uncommon to have the road closed up to 10 hours while the debris is being cleared off the road. Realizing that the transition área above the highway was fairly large, the Colorado Highway Department requested assistance in layout and design of possible avalanche control structures. During the summer of 1958, a plan of attack was formulated against this avalanche. Considerations of available time and funds had to be two of the factors involved in planning the type of construction to be accomplished. Due to the type of terrain and available material in the transition zone, the diversion type barrier was chosen as the most advantageous type of installation. The original layout and design consisted of 2 diversion type barriers each 20 to 30 ft. in height. Approximately midway in the slide path is a narrow chute that most of the snow flows through. At the bottom of the narrow chute are two rock outcroppings that form a cliff about 30 ft. high. The first barrier was started approximately 200 ft. below these rock cliffs. ( See schematic diagram.) The barrier started out for 200 ft. subtending an angle with the fali line of about 30°. At the 200 ft. mark down the barrier it started to turn slowly upward so that a gentle are led into the timbered área on the east edge of the slide path. Another barrier, a twin to the first, was designed 200 ft. below; but due to a misunderstanding, the barrier was constructed perpendicular to the fali line. |