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e e e Powell then goes on to discuss the Anderson Bottom and the development of the abandoned meander (Photo 2). He named the river bend Bonita Bend and described the floodplain as having a little meadow between the river and cliff. The river in this reach is relatively narrow and deep, with steep, high banks exposed at low flow. The historic river channel had several wide reaches with active sand bars which have now become colonized with vegetation and attached to the river banks. The reach is characterized by a densely vegetated floodplain terrace with old tamarisk trees, willows and other riparian vegetation that has greatly restricted access between the river and the upland vegetation zones on the river terrace. Some of the bottoms such as Queen Anne, Anderson, and Valentine have mature stands of cottonwoods or several solitary trees crowded by tamarisk. Most of the older sand bars, islands and terraces have vegetation so dense that it is impossible to walk through it. Twenty-two cross sections were surveyed in the Canyonlands study reach (Figure 3). These cross sections were located to accurately predict water surface elevations in the river. Three of the side canyon channel mouths were also surveyed; the two Anderson Bottom side canyon channels and the Millard Canyon channel. Like the Ouray cross sections, surveys were performed at base flow prior to the seasonal rising limb, at peak flow, and again at base flow in September. The cross section endpoints were established and surveyed in the same manner as the Ouray cross sections, with a Bureau of R~clamation survey crew establishing endpoint elevations and coordinates. Plots of the cross sections are provided in Appendix A. There are five ephemeral tributaries with side canyons that have backwater habitat associated with incised channels crossing the floodplain terrace or the bedrock adjacent to the Green River. These are Millard Canyon, two ba~kwater channels in Anderson Bottom and two channels in Holeman Canyon across from Valentine Bottom. T~o of these side canyon channels, the Millard Canyon channel and Anderson Bottom downstream channel, have been extensively sampled in the past for razorback sucker larval fish during peak flows. In 1995, the Holeman Canyon backwater channels were also sampled. The side canyon backwater habitat in this reach represents one of the last opportunities for larval fish to escape the main current by seeking low velocity areas before they drift to Lake Powell. Photo 3 shows the Millard Canyon backwater area which is typical of these relatively small, narrow habitat areas. These areas are in contrast to the extensive bottomlands in the Ouray reach. 9