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fruit products, especially Elberta peaches, and has continued to the present as a major fruit growing center. Completion of the Highline Canal irrigation facility in 1915 assured an adequate water supply to the area and furthered economic stimulation in the region. The population of Palisade in 1980 was 1,551 (Reference 2). The Colorado River rises high in the Rocky Mountains on the western slope of the Continental Divide. The river flows in a general southwesterly course from its headwater regions to the vicinity of Palisade and Grand Junction where it turns to the northwest for most of its remaining course in Colorado. Elevations range from approximately 4,700 feet at Palisade to more than 12,000 feet in the headwater regions. The drainage area of the Colorado River above Palisade is approximately 8,800 square miles. The climate of Palisade is arid and yearly precipitation averages approximately 9 inches. Temperatures are often in the 900F range in the summer and below freezing in the winter. Occasionally, summertime temperatures may exceed 1000F and winter temperatures may drop as low as -20oF. Natural vegetation in valley areas consists of cottonwood and willow, desert shrub, and an understory of hardy grasses. Mesas and lower mountain slopes between 5,000 and 8,000 feet support oak, big sagebrush, Douglas fir, pinon pine, and juniper. 2.3 Principal Flood Problems Most of the annual precipitation in the higher regions of the Colorado River Basin occurs as snow, and a deep snowpack usually accumulates. General rainstorms covering large areas for extended periods can occur in the region during spring, summer, and fall. Convective-type cloudburst storms of small areal extent, which account for approximately one-half of the normal-annual precipitation, can be expected during summer and fall in the Palisade area. However, flooding along the Colorado River is normally the result of rapid melting of the mountain snowpack in spring and early summer (late May through early July), with floodflows occasionally augmented by rain. General rainstorms and convective-type thunder- storms generally have little effect on a stream as large as the Colorado River. In the study area, 100-year floods on the Colorado River would result from snowmelt runoff, and 500-year floods would result from snowmelt augmented by rain. Damage resulting from a 100-year or 500-year flood would principally be associated with agricultural and rural residential areas, and public facilities. Residential losses would include damage to foundations, lower floors, walls, furnishings, appliances, and lawns and gardens. Agricultural damage would involve erosion and deposition of silt and debris on crop and pasture lands. Public facility losses would comprise damage to streets, highways, bridges, and irrigation and sewage treatment systems. Other costs 4