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The screen panels will be removed for servicing by use of a gantry crane for this option. Removal of the screen panels with a mobile crane from the riverbank would be difficult because of the long reach required. Also, it will not be possible to de-water in front of the screens for access to the screen panels. The crane will run on rails that extend the length of the structure and over a concrete deck near the sluice gates. During high flow conditions in the river, the sluice gates will be open and flow will pass over the diversion dam. During low flow in the river when the sluice gates are closed and the river water level is at or slightly below the top of the diversion dam, a bypass flow be required to pass fish and debris down the river. This will be accomplished by modifying the existing sluice gate structure to include a concrete bypass chute. This location is shown on Photo 15 in Appendix A. The structure will be located in the area shown at approximately the center of the photo. An angled or curved wall extending from the end of the last screen to the bypass chute will direct the flow to the bypass. The bypass will be designed to pass a minimum flow of 30 cfs. The chute will be equipped with some type of gate to regulate flows. At critical low water times of the year, the only flow in the river below the diversion dam may be the 30 cfs bypass flow. This may require a low flow channel to be excavated to a location of the natural low flow channel in the river, or possibly to a point below the OMID return flows. At high flow conditions in the river this channel may become blocked with sediment. This would require the channel be cleaned out prior to low flow times of the year. ," A critical concern with this option is the possibility of a large volume of sediment in the river 20 .:.:.~.-J I I I I I I I I I I I I I I I I I I I