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, " ~ . . -4- entrance to the whitewater bypass); or more likely, the hydraulic profiles through the entire system carefuIly studied to adjust the desired water surface at the sensing point that will result in the correct split of flows upstream between the whitewater bypass and the intake channeL 6. You explained that the area along the intake channel was to have a vertical grate or rail system to prevent the lateral inflow of boaters into the intake channel. Lateral inflow into the intake is D.Q1 a desirable feature. Flow should enter the intake channel from the upstream to encourage optimum intake performance. Originally we were going to modify the river bottom after observing intake performance following initial construction in order to minimize any negative influences from lateral inflow. This was never done because of the pending whitewater improvements. ~ It appears desirable to raise the west wall of the intake channel to force the water flow to enter from the upstream, and prevent lateral movement of boaters into the intake channeL This wall presently has a top elevation of 88; thus, a much higher wall elevation will be needed. It may not have to be as high as the IOO-year flood. The differentials in flood elevations on either side would have to be studied. We would suppose that as long as the intake channel water surface was clearly higher than the adjacent whitewater bypass water surface (e.g., no potential to cause flow into the intake channel) that the divider wall would not have to be any higher than such a profile. Of course, this presumes that boaters could not get into the intake channel and then subsequently fall back into the bypass laterally. Measures to manage debris are important. This would probably require measures at the entrance/control area upstream of the bypass and intake channe~ and near the radial gate. At the radial gate, this requires a notch through the wall to allow debris which accumulates at the debris boom to slide back to the main river flow and not accumulate at the radial gate. Again, all of this requires detailed hydraulic profIles for a wide range of flows. 7. Another point which may need to be taken into consideration is the future expansion of the intake. The facility was designed to be doubled in the upstream direction, including the intake and the pump station. Therefore, it may be advisable to locate the intake to the whitewater bypass further upstream compatible with the future intake, or if the entrance to the whitewater bypass is fairly inexpensive at least consider where it would ultimately be relocated.