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1884 flood is greater than 500 years and that of the 1921 flood is 80 years. Estimated elevations of potential flooding on Little Salt Wash and the Colorado River are shown in Figures 2 and 3. In Figure 2, the 100-year flood elevation is shown to be approximately 0.5 foot below the low chord of the U.S. Highways 6 and 50 bridge. The 500- year elevation is shown to be approximately 1.5 feet above the top of the road. In the photograph of the Colorado River in Figure 3, taken upstream of the State Highway 340 bridge, high-water mark on the piers was caused by a peak discharge of approximately 33,000 cfs. The peak flow occurred on May 24, 1970. The photograph was taken during a minor flood which, according to USGS stream gage records, achieved a di scharge of 25,000 cf s. A rat ing curve was drawn upstream of the State Highway 340 bridge and, based on the results of this study, showed very close agreement with the high- water mark. Damage resulting from the 100- and 500-year floods presented in this study will be largely confined to agricultural and undeveloped lands as well as numerous stream crossings. 2.4 Flood Protection Measures There are no flood protection measures in existence at Fruita, and there is no flood regulation upstream on Little Salt Wash. Major reservoirs controlling the Colorado River above Fruita are Granby, Green Mountain, Dillon, Williams Fork, Reudi, Taylor Park, Vega, Paonia, Morrow Point, and Blue Mesa. The following table gives the storage capabilities and appro~imate locations of the reservoirs: Table 1. Flood Protection Structures Reservoir Name Storage (Acre-Feet) Approximate Distance Uostream of Fruita (Miles) Colorado River Basin Above Grand Junction Granby Green Mountain Dillon Williams Fork Reudi Veg 465,600 146,900 254,000 96,800 103,200 34,760 195 170 195 170 125 60 Gunnison River Basin Above Grand Junction Taylor Park Paonia Morrow Point Blue Mesa 106,200 20,950 121,200 829,600 150 90 100 100 7