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relationships for each site were determined to estimate a range of flows necessary to inundate the bottomland site. However, the flows that were estimated to flood each of these bottomland sites should be considered provisional in this report until empirical verification can be obtained for these sites. Flow information was also used to determine the frequency that predicted flows might now occur at each bottomland site. In the Green River drainage, of the seven sites evaluated, the Woods Bottom (Old Charlie Wash) bottomland site within the Ouray National Wildlife Refuge floods the most frequently, between 95-100% (i. e., between 9-1/2 and 10 years out of 10). Sheppard and Johnson Bottoms flood approximately 65-75% and 40-45% annually, respectively. The Baeser Bend site floods less frequently, only about 10-200 (one to two years out of 10). In the Colorado River drainage, of the nine sites evaluated, the Griffith bottomland site in the 15-mile reach of the Colorado River floods the most frequently, about 50% (one year out of two). The frequency of flooding at the Confluence Park bottomland site (an oxbow) on the Gunnison River now occurs only about 10-15% (one to one and one-half years out of 10) since the construction of upstream dams; a tertiary side channel at the Adobe Creek site is inundated about 20- 25% (two to two and one-half years out of 10). Many of the other sites are now inundated less frequently because of the loss of the (historical) high- volume years, which are important to inundating off-channel habitats in the floodplain. Not only has the magnitude of runoff flows in May and June been reduced by about 45% in both the Colorado and Gunnison rivers, and by 22% in the Green River but the duration of flooding has also been reduced. Much of this is a result of upstream water development projects, primarily transmountain diversions and reservoir storage. The construction of levees and dikes, particularly along the Colorado and Gunnison rivers, has further reduced the likelihood of flooding by further isolating the floodplain from the main stream reaches and preventing water access during runoff. Given the present hydrologic regime, current water availability, and future compact water development in the Upper Colorado River Basin, inundating bottomland sites might be best accomplished by removing portions of- or entire human-made dikes or natural obstructions (e.g., levees) to increase flooding frequency. Those sites that flood more frequently under the existing hydrologic regime will also flood more frequently in the future, and will provide more benefits to endangered fish. The priority recommendation was to collect additional flow and elevation data during runoff in 1995 at seven bottomland sites established in 1994 on the Green River and at four bottomland sites (Pike's and Adobe Creek on the Colorado River and Confluence Park and Johnson Boy's Slough on the Gunnison River) established in 1994 to verify and refine stage vs. discharge relationships. These data are particularly important for estimating flows necessary to inundate bottomland sites and vital in determining which sites can be practically restored. Other recommendations include, 1) completing contaminant screening for the remaining 19 bottomland sites investigated in 1994, 2) determining if three bottomland depression sites along the Colorado River between Moab, Utah, and the Green River confluence have suitable habitat for restoration, 3) obtaining a complete set of current color aerial photographs of the entire Upper Colorado River Basin, and 4) developing alternative or additional selection criteria, if warranted by site visits, to xv