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e wide river valley bounded by sandstone bluffs. The freedom of the channel to migrate within this meander belt has resulted in the creation of the bottomland floodplain features. The Ouray National Wildlife Refuge was established in 1961 and began operations in late 1962. Prior to that time some of the bottomlands within the refuge boundary were farmed. Although some natural levees along the river may have existed in Old Charley Wash, Sheppards Bottom and Leota Ponds, most of the existing levee system was constructed to create waterfowl ponds. The Leota ponds and levees were constructed during the period from 1967 to 1970 and have obliterated evidence of the old channels across the floodplain. These levees have reduced the frequency with which the Green River floods the bottomland areas. Most of the bottomlands were flooded in 1983 and 1984. e A total of 36 cross sections were surveyed in this 16 mile reach. The cross section locations shown in Figure 2 and Exhibit 1 were selected with respect to local hydraulic controls to calibrate and predict water surface profiles with Corps of Engineers HEC-2 (U.S. Army Corps of Engineers, 1990) hydraulics model. The cross sections were established with endpoints consisting of a marked aluminum survey cap mounted to a 3 ft piece of rebar and driven to ground level on each side of the river. Behind the bar and cap (B&C), away from the river, a tag-line-post (TLP, a T-fence post), was installed to attach the survey cable to span the river. Both the B&C and TLP on each side of the river were surveyed for elevation and horizontal position with a total station by a Bureau of Reclamation survey crew. Plots of the surveyed cross sections are provided in Appendix A. Canyonlands National Park The Green River study reach in Canyonlands begins at river mile 25.3 upstream of the confluence with the Colorado River and extends to river mile 34.5 just upstream of Millard Canyon. The river is confmed to a canyon with relatively narrow floodplain and terraces. Photo 2 provides a good example of the typical characteristic of this reach. Historically, occasional peak flows covered the floodplain to the base of the vertical sandstone cliffs. Powell's (1895) description of the Green River in the vicinity of Bonita Bend, about the midpoint of the study reach, is as follows: In many places the walls, which rise from the water's edge, are overhanging on either side. The stream is still quiet, and we glide along through a strange, weird, grand region. The landscape everywhere, away from the river, is of rock---cliffs of rock, tables of rock, plateaus of rock, terraces of rock, crags of rock---ten thousand strangely carved forms; rocks everywhere, and no vegetation, no soil, no sand In long, gentle curves the river winds about these rocks. e 6