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Channel Cross Sections Two or three permanent cross-channel transects were established at each of the five study sites. Reinforcing-rod head pins were placed on both sides of the river as permanent marks for the transect. Complete cross sections were surveyed in late summer or early fall when water levels were low and surveying could be more easily done. A marked, kevlar cable was stretched between two fence posts at either end of the transect. Surface elevations (t 0.1 ft) were measured along the cable using a surveyor's level and a 25 ft-long level rod. Ground and river-bed elevations were usually taken at 10 ft intervals or at significant changes in slope, whichever was smaller. However, elevations on gradual slopes away from the river channel were taken at 20-ft intervals. Water surface elevations were measured on both sides of bars, islands, and the main channel along the transect. Also, water surface elevation was measured at one end of each transect every time that surface habitat was mapped. Water velocity and substrate size were not measured. Bed profiles were plotted to display changes in bed elevation between measurements. One to six water-surface elevations were plotted on the profiles as reference points. Staff Gauges frying and Burdick (1995) identified several important bottomlands within the Gunnison River study area. They placed staff gauges at some of these bottomlands to monitor water levels and estimate flows needed to inundate the floodplain habitats. They monitored temporary staff gauges in 1994, a year of moderate spring runoff. Even though some of the important habitats did not flood that year, stage- discharge relationships allowed them to predict when flooding might occur. When 1995 promised to be a high-runoff year, the temporary staff gauges were replaced at Confluence Park (RM 57.1; 0.8 mi upstream from the confluence of the Gunnison and Uncompahgre rivers) and Johnson Slough (RM 53.6) to validate the stage- discharge predictions (Irving and Burdick 1995). A third staff gauge was placed in an old oxbow of the Gunnison River in Escalante SWA (RM 52.3) that was part of Study Site 5. Water surface elevation at each of the staff gauges was recorded once or twice a week during runoff. Channel cross sections were surveyed at each site and bed-elevation data were related back to the staff gauge. Bed profiles were plotted and representative water elevations were placed on the graphs to visually assess when over-bank flooding occurred . River Discharge River discharge was measured by USGS gauges on the Gunnison River near Grand Junction {09149500; RM 14.6) and near Delta (09144250; RM 57.6; Figure 6