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1. INTRODUCTION Flooded bottomlands located along the Green River are believed to be an important nursery habitat for the endangered razorback sucker. The goal of the Habitat Restoration Program is to restore or enhance natural floodplain functions that support recovery of endangered fishes in the Upper Colorado River Basin (as outlined in Final Conceptual Framework for the Habitat Restoration Program). This document presents the results of sedimentation and erosion monitoring at eight restored floodplain sites along the Green River near Vernal, Utah. Three of the bottomland sites, Bonanza Bridge, Stirrup, and Old Charlie Diked were restored in the spring of 1997. Therefore, there are two years of monitoring data (changes after the 1997 and 1998 runoff seasons). The remainder of the sites were restored in the fall of 1997 or spring of 1998. These include the Horseshoe Bend, Baeser Bend, Above Brennan, Johnson-4, and Leota 7/7a bottomlands. Only one year's worth of monitoring data are available for these sites. Project Goals and Objectives The project goal was to quantify erosion and sedimentation at the restored bottomland sites. Results of the monitoring studies will give the Recovery Program a better idea of how different floodplain restoration site configurations work to provide fish passage to these valuable habitats, and how long they will maintain their connectivity to the river. Ideally, these sites will provide adequate fish passage to the floodplain habitats at more historic flood frequencies and durations and require little or no operation and maintenance to keep these sites accessible to endangered fish species. This report addresses Recovery Implementation Program Recovery Action Plan (RIPRAP) objectives of restoring and managing bottomland habitat and conducting site restoration. • Specific objectives of this study were to: • Provide as built surveys as baseline data for future erosion and sedimentation monitoring., • Collect hydrographic data including river cross section surveys, bottomland cross section surveys, inlet/outlet cross section surveys, and topographic mapping of the manipulated areas. • Develop a photo documentation record to monitor changes at the restoration sites. • Present quantitative and qualitative results of the erosion and sedimentation monitoring to help identify best management practices for current and future floodplain restoration activities. A more detailed discussion of the design objectives, river hydraulics and hydrology, specific site configurations, and locations of these sites are presented in the "Green River Floodplain Habitat Restoration Investigation, Bureau of Land Management Sites, and Ouray National Wildlife Refuge Sites near Vernal, Utah, Final Report (FLO, 1997)." This report focuses on the specific results of the erosion and sedimentation monitoring at each individual site. • 1-1