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Bridget's death to lack of information to us, and misjudgment of the magnitude of the situation on her part"[30]. f. Detection systems. - Lawn Lake Dam was not equipped with instrumen- tation to detect and report dam failure. Very few dams are equipped with remote sensing equipment; however, rapid progress is being made in this field, including methods for transmitting data via ground-based and satellite telemetry. Installing such equipment raises issues such as who should pay for installation and maintenance, and who should be responsible for monitoring and analyzing the transmitted data. g. Warning dissemination. - There was no written plan for evacuating people from the flood plain which incorporated the use of the local radio station [20, 29]. A reporter from radio station KSIR experienced some difficulty in obtaining up-to-date information from the Estes Park police headquarters [29]. This could have been critical because the interviews conducted by the authors indicated that some flood plain occupants were directed by law enforcement officials to turn their radios on to get additional information. Discussion Deciding who to warn. - A description of the area that would be flooded If Lawn Lake/Cascade Lake Dams failed was not available before the flood. The area within which warnings and evacuation orders were given was based upon observations of the flood and its progress downstream. Judging from the fact that there were no fatalities outside the National Park, the warning process' was highly effective. However, the various reports and interviews indicated that a description of the recolllllended evacuation area can be misinterpreted. People generally were evacuated if they were horizontally within 50 feet of the river (in addition, to, the downtown area). However, Park Service documents indicate that initial discussions were to evacuate "up to the 50-foot level above the stream" [9]~. The most sophisticated engineering teChniques available would not have been able to predict the exact size and timing of the flood as it passed through Horseshoe Park and further on downstream. Although detailed topographic mapping can always be obtained, maps with 40-foot contour intervals were the best that existed for the upper reaches. The depth of overtopping which would cause Cascade Lake Dam to fail, and hence the size of the flood surge and timing could only have been estimated. Detailed information on a micro- scale could not have been accurately developed, even though it has a critical effect on the evacuation plan. Hydrologists in State and Federal agencies familiar with dam failures expressed surprise over the large magnitude of the flooding that occurred in Estes Park. Prior to the failure, ,Lawn Lake Dam was classified as a significant/moderate hazard dam by the State and Corps of Engineers. This hazard rating means that potential loss of life would be few (Corps) or none (State) due to the lack of urban developments and the small number of inhabitable structures. It is likely that any description of flooding which would be caused by the failure of Lawn Lake Dam, prepared prior to the 10