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I I I I I I I I I I I I I I I I I I I formation that is fairly well vegetated. Banks on this side are about 5 feet high and bank slopes are more gradual than along the west bank in most areas. Near the upper part of the reach the east bank has evidence of undercutting and appeared to be near vertical. The bar deposits appear to be a mixture of larger cobble and sandy gravels, and bed material seemed to be coarser than in the lower reach. A fairly deep pool exists along the outside of the meander bend, and a pronounced riffle exists near the upstream limit of the protection measures along the west bank. There was evidence of failed bank protection measures that consisted of log bundles and large rounded boulders along the west bank at the upper end of the existing revetment. Two property owners have structures along the west bank. There was evidence of large boulders being stockpiled in the eastern overbank. Reach 4 (Section 6 to Section 7) - This reach extends from approximately 3,000 ft upstream of U.S. 40 to approximately 3,900 ft upstream of U.S. 40. The channel banks are near vertical in many places with heights between about 4 to 5 ft. Tension cracks were noted along the west bank, and it appeared that block failures had occurred. The west overbank appeared to be relatively low and flat. There was evidence that flows in excess of the channel capacity would be able to spill towards the West Fork of the Elk River. A large point bar exists along about half of the east bank. Towards the upper end of the reach, the east bank became near vertical and a more resistant formation was apparent. Another small irrigation diversion culvert was also located on the east bank near the upper limit of the reach. Reach 5 (Section 7 to Upstream Limit) - This reach extends from approximately 3,900 ft upstream of U.S. 40 to the upper end of the study reach near the diversion structure for the West Fork. At the lower end of the reach, the east bank rises almost vertically to about 30 ft high. This is along the exposed formation noted in Reach 4. This portion of the river is characterized by numerous bar deposits, both point and mid-channel. At the upper end of this reach, the channel has an almost braided character. Many of the deposits appear to be well vegetated. There was evidence of cattle trampling along the west bank that can contribute to bank instability. This appears to be a segment of the river that has experienced a significant amount of channel adjustment. This may have partially been a result of past dredging efforts within the channel. Stabilization efforts were apparent along the west bank at several locations. A large stockpile of river rock was adjacent to the west bank midway along the reach: A number of old stone jetties and revetment appeared to have been somewhat successful in reclaiming some of the bank just downstream of Section 8. There were several areas where higher flows would be able to spill from the channel and either rejoin the channel further downstream or continue westward toward the West Fork of the Elk River. Between Section 8 and the West Fork diversion structure, there was a low area paralleling the channel where it appeared some type of heavy equipment had come through and cut into the channel. Further evidence of heavy equipment disturbance was upstream of the diversion structure along the western portion of the channel. Dredged material appeared to have been pushed up along the bank in this vicinity. Additional stone spur dikes also exist on the west bank upstream of the West Fork diversion structure. 27