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4. Negative factors: Controllable.- a. "Dam Failed" not in warning message. - The warning delivered within the walk-in sites at Aspenglen Campground did not uniformly state that a dam had failed [28]. The following description of responses to flood versus dam failure warnings issued in the Big Thompson Canyon during the 1976 flood illustrates the importance of the dam failure message: "* * * a sheriff I s deputy came into the restaurant to warn people of rising water and possible flooding. He instructed them to cross the river and climb up the mountainside. The people took no action in response to this warning. Twenty minutes later he returned with the message that the dam at Estes Park had broken and the people in the restaurant should cross the river and climb immediately. People did respond to this second warning. . . So~~ perceived no danger from a flash flood warning yet responded quickly to the message that the dam at Estes Park had broken"[17]. The threat of a flood from a dam failure seems to mobilize people to action because they can appreciate the suddeness of the threat. Unlike floods from rainstorms, for which people seem to expect considerable advance environmental clues (e.g., hard, steady rainfall), people appreciate that a flood from a dam failure can occur when everything else seems normal [17]. ' b:' Location of public facilities. - Aspenglen Campground was located a short distance downstream from Cascade Dam. Portions of the campground were within the 100-year flood plain. Access into and out of walk-in sites was by bridge; thus, there ,was only one path to safety rather than many. Access to the entire campg~ound was by a single road which , became impassable due to floodwaters thereby preventing rangers from reaching the campground to issue additional warnings. c. Flood plain development. - Many of the motels and other structures flooded were located only a few feet above the river. Estes Park and Larimer County had adopted ordinances tied to the 100-year flood standard for new construction. Currently accepted hydrologic tech- niques, which do not consider structural failure, projected a 100-year flood elevation for the town and county which placed minimal restric- tions on new flood plain development. d. Public information. - There were no signs in Aspenglen Campground warning people of flood hazards and what to do in a flood situation. e. Lack of understanding among flood plain occupants of the gravity of' the situation. - The true magnitude of the flooding that would occur in Aspenglen Campground was not conveyed in the warning message given to the walk-in campers. The following statement illustrates this: "I did not find out for many minutes that a dam had broken, I attribute 9