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Project #3 and #4 conditions may cause increased flow depths by as much as 13.6 to 16.6 feet compared to existing channel conditions. . Project #3 and #4 conditions may cause significant increases in channel velocities at the peak of the SPF. , A large volume of sediment was deposited at the downstream end of the levees. This was due to a rapid flow expansion which resulted in a decrease in transport capacity. Most of the material removed from the bed in the leveed reach was deposited in this area downstream from the project. Computed results indicated that this deposited material may be removed over a long period of normal flows as the bed profile adjusted itself to an equilibrium slope. . The results showed significant deposition at the area near the upstream end of levee 3. This was due to decreased velocities caused by a backing up of water at the levee constriction. . The above points indicate that the same patterns of scour and deposition can be expected for either project #3 or project #4 levee configurations. The higher velocities and greater water depths associated with the project #4 configuration would necessitate increased toe protection for the levees. Based on this fact, the project #3 configuration would seem to be more efficient than the project #4 configuration. Most of the scour in the reach between river mile 1196.9 and 1198.9 occured prior to the peak flow. This indicates that a small factor of safety may be present for levee heights designed using a stationary bed model such as HEC-2. In areas of deposition, however, designed levee heights may be insufficient. . The Anderson and King Arroyos may become significant sources of sediment during a flood event. This factor was not accounted for in the single-event analyses. The Anderson Arroyo (Fig. 5.1) feeds into the Arkansas River at a reach where deposition occurred under project conditions. The result may be increased sediment deposition and higher river stages at this location during flood events. . The analyses discussed herein have considered only the one-dimensional steady flow aspects of the channel conditions. Further detailed analyses of bank erosion and levee toe protection may be warranted. The hydraulic characteristics of the channel in the vicinity of cross sections 1199.2 through 1199.5 are very complex. Flows are directed almost perpendicular to the upstream end of levee 3. Significantly higher velocities may occur here. Multidimensional studies may be necessary to properly evaluate potential bank erosion and design problems. , Increased stormwater area of La water depths outlet design Junta. within the project may necessitate special considerations to properly drain the central . The above analyses did not take into account the flow of debris that is likely to occur during a large flood event. Trees and other large objects can clog channels or lead to local areas of deposition that are much greater than the average deposition computed by HEC-6 and shown in Tables 5.1 through 5.3. 62