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Colorado Earthquake Hazard Dam Failure Approximately 27,000 darns exist in Colorado. Of these, 584 are of such size, and hold back sufficient volumes of water, to be considered Class I High Haz- ard (236) or Class II Moderate Hazard (348) darns. These Class I and Class II darns pose a considerable threat to downstream population and property. When many of Colorado's darns were originally con- structed, they were not designed for seismic activity. While new darns in Colorado are much safer because of the additional scientific knowledge collected in the intervening decades and the advances in engineer- ing design and construction techniques, the older dams pose a potentially significant danger. Although some darns fail because of other natural disasters, there is also a possibility that earthquake ground shaking could contribute to darn failure in Colorado. Colorado Seismic Network In December of 1961, the Colorado School of Mines installed a three-component seismograph in the Cecil H. Green Observatory at Bergen Park, about 14 km southwest of Golden. This system has been in continuous operation since installation and is now the primary source of instrumental data on Colorado earthquakes. The Bergen Park station, designated GOL by the worldwide standardized seismograph network, is thought to be capable of locating Colo- rado earthquakes to within 15 km of their epicenter. During part of 1971 and 1972, the Colorado School of Mines and NOAA jointly operated a seven-station, statewide monitoring network. Colorado earth- quakes were located with much greater accuracy (1 to 5 krn) during this period. Although smaller net- works of seismic stations have been in operation in various regions of the state from time to time during the past few decades, overall seismic monitoring in the state of Colorado is not complete. Colorado Earthquake Hazard Reduction Program (CEHRP) The Colorado Earthquake Hazard Reduction Pro- gram (CEHRP) is part of the National Earthquake Hazard Reduction Program (NEHRP). The program was established to reduce loss of life and decrease economic losses from earthquakes. Colorado has been identified as a moderate earthquake state by NEHRP. The CEHRP is a cooperative program with goals to reduce loss of life and injury and decrease damage and economic losses from earthquakes and other natural hazards in Colorado. The Colorado program focuses on: . mitigation measures . education and training . technical assistance to local governments, busi- nesses, and citizens of Colorado. The CEHRP Five-Year Plan identifies program goals that include the following measures: . further assessment of seismic hazards and risks throughout Colorado . vulnerability assessments of susceptibility to earthquakes in different regions of Colorado . public awareness and public education about seismic hazards and risks in Colorado . technical training in connection with building professionals in design and construction . training in mitigation, pre-disaster prepared- ness, and post-disaster response for local gov- ernments and the private sector. Federal-State-CSU Program Early in 1991, the Colorado Office of Emergency Management (OEM) applied to the Federal Emer- gency Management Agency (FEMA) for inclusion in the federally funded National Earthquake Hazard Reduction Program (NEHRP). This program pro- vides funds directly to state government for earth- quake preparedness, planning, and mitigation projects. Colorado was declared eligible for program participation in April of 1991. The Colorado Earth- quake Hazard Reduction Program (CEHRP) is being implemented with a joint effort of the Colorado Of- fice of Emergency Management and Colorado State University (CSU). The Earthquake Hazard Mitiga- tion Subcommittee serves as the Colorado Advisory Board for the CEHRP. Funds for the program are distributed by FEMA to OEM as program manager, 33