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r L ~ . Dramatic changes in the cross sections are not anticipated in the channel around the spawning bar. Sand deposition over the cobble bar will probably be cyclical depending on a combination of watershed sediment yield, current year basin hydrology (wet or dry year), peak flow and location of sediment storage in the river system. The long term response to changes in the regulation of Green River flow may effect the sand deposition around the spawning bar. The established cross sections should be effective in monitoring future river response to the flow hydrology of the Green River. B. Wetlands Topography. To complete the design of the wetland hydraulic connection to the river, the wetland topography should be surveyed. The detailed survey of the wetlands should include the following: • Channel inlet area for the design and excavation of an stable flow intake, sediment exclusion area and channel, diversion gates, and channel way. See Figure 2 for a conceptual design of the inlet area. • Completion of the survey of the potential channel from the inlet to the wetlands. The channel alignment should follow the old meander thalweg near the bluff line unless precluded by high selenium concentrations. • Completion of the survey of return -flow drainage from the wetlands to the river. • Topography of the wetlands area to identify optimum areas of inundation, wetlands water volumes, sediment dead storage, and diversity of topography and vegetation. This level of survey detail would then permit an estimate of excavation or fill quantities. Obviously, it would be important to minimize the wetland disturbance. The detailed survey would enable an evaluation of the best inlet design location. C. Hydraulic Design of Wetlands Inflow/Outflow. The hydraulic design of the diversion structure to the wetlands would require decisions regarding: • Frequency of wetland inundation. • Inflow discharge to the wetlands. • Wetlands water surface control. • Maximum volume of the ponded water storage in the wetlands. • Potential need for a pool reserve of sediment dead storage in the wetlands. • Water right considerations. 38