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The staff gauge water-level changes were recorded on computer spreadsheets. Daily streamflow data were obtained from USGS stream gauges nearest the bottomland site for dates and times when stage elevations were recorded. This information was used with BR flow models to determine a stage vs. discharge relationship for each site. From several hundred possible equations, this model provides the equation which best describes the stage vs. discharge relationship and the regression correlation coefficient. The information was used to estimate flows necessary to inundate each of the bottomland sites. Channel Cross Sections To determine if channel configuration (depth and width) at each of these bottomland sites would remain constant or change over time with various discharges, it was necessary to obtain streambed profile information. If there were a change, this might affect the amount of flow necessary to inundate the site or the amount of fill material that would have to be removed to allow water access to the bottomland site. Therefore, transects were established at each bottomland site where staff gauges had previously been located. Kevlar cable was stretched across the entire channel between two steel fence posts. Channel cross sections usually encompassed the entire 10- year floodplain. Transects were surveyed by BR personnel from high points from the right shoreline to the left shoreline that crossed secondary and tertiary channels, backwaters, and islands. All distance and elevation measurements were obtained with an electronic distance meter (EDM), that corrected for up- and downstream distances from the transect. Across the transect, elevations were recorded at every 10-foot interval or at every significant grade break. Bed width was plotted against either absolute (Green River) or relative (Colorado and Gunnison rivers) elevations. River Discharge Mean daily streamflows were correlated with the dates when staff-gauge data were obtained. Also, mean daily flows for pre- and post-water development periods were obtained to generate flow exceedences. The period of record at a stream gauging station that best represented present water availability which would inundate a bottomland site was used. The Jensen, Utah gauge was used for bottomland sites adjacent to the Green River. The pre-water development period, 1947-1966, and post-water development period, 1966-1993, were analyzed at the Jensen gauge. For the two sites on the Gunnison River, the Delta gauge (1977-1993) was used for the Confluence Park bottomland site and the Whitewater gauge (1967-1993) near Grand Junction for the Johnson Boy's Slough site. Stateline gauge (1952-1993) was used for the Adobe Creek site along the Colorado River. The Cameo gauge (1952-1993) was used for the two sites between Debeque and Rifle, Colorado. For the four bottomland sites in the 15-mile reach, a different approach was used to determine streamflows. Although there is a USGS stream gauge immediately downstream of the Grand Valley Diversion, there are only three years of flow data. Therefore, the mean daily flows at the Cameo and Plateau Creek (1970- 1993) stream gauges were summed and the water diversions at Government 13