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Cross sections were taken at several locations to determine the natural river characteristics such as <br />bank -full elevations, channel width and depth, and thalweg depth. This data was used to calibrate the <br />stream gage data to determine the most accurate river channel dimensions in order to restore <br />functionality to the channel so that water and sediment can be efficiently transported. The net result of <br />this analysis is the channel characteristics previously presented. <br />Sites 5 and 6(see Reclamation Plan figure) are bank -full benches that will be constructed at an elevation <br />that is 8.5 feet above the mean channel depth and match existing bank -full benches. Material for these <br />bank -full benches can be excavated from the scour pool below the j -hooks (see Figure 6). <br />J hooks (see attached Figure for construction details) will be constructed at locations 4 and 6. It is <br />estimated that 800 rocks (minimum 4 to 5 ft. in diameter) will be required to construct these bank <br />stabilization structures. A trackhoe with a thumb will be needed to build the J -hook structures. 1 -hooks <br />provide several important functions for bank stabilization and river channel functionality. First, the <br />structures will force water from the banks into downstream scour pools and dissipate the energy of the <br />river. Short vanes to protect the river bank at Site 5 will be constructed, and with the 1- hooks, begin to <br />force the river into a natural meander that matches meander geometry upstream and downstream of <br />the project area. <br />J -hooks will be constructed using footer rocks that extend 5 to 7 feet below the design stream bed. <br />These footer rocks are critical to ensuring the stability of in- stream structures under high -flow <br />conditions. Scour pools that develop below the J -hooks will provide valuable fish habitat as a bonus. <br />Toe wood will be placed at locations designated by the Sites 5 and 6. Approximately 200 logs are <br />needed to stabilize the river banks. The logs need to be at least 20 feet long and can be obtained from <br />local sources such as trees downed by beavers or rejects from local lumber mills. The majority of the log <br />is buried in the river bank with the end of the logs sticking out into the low water channel in random <br />directions as shown in the attached photo (at least 80 percent of the log is buried in the bank). It should <br />be noted that the majority of the logs will be placed below the water surface even in low flow <br />conditions. This will ensure that the logs do not decompose and prevent safety issues for boaters. A <br />significant benefit from the toe wood is the reduction of shear stresses on the river bank plus the wood <br />provides favorable fish habitat. <br />Once the bank stabilization structures are completed, the diversion channel will be filled in, and the area <br />designated as Site 7 on the Reclamation Plan map will be sloped into a point bar. This area will act as a <br />flood plain for future high flows. <br />It is important to note that there may be design changes based on information gained during <br />construction. These changes may include modifying or moving bank - stability structures and channel <br />modifications. Any changes will be an attempt to maintain the hydraulic design in an efficient manner. <br />