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Two years of monitoring at the restored bottomland sites have demonstrated that 'the erosion and <br />sedimentation processes are quite dynamic. Different processes will be experienced year to year <br />depending on the magnitude, duration, and rates of filling and draining of the sites. Two years of data are <br />not sufficient to determine any long term erosion and sedimentation trends. Changes have been <br />experienced, but the floodability has not changed drastically. The scouring of outlet channels that <br />maintain or even increase the floodability has complemented deposition at the mouths of the inlets. Thus <br />far, none of the data has indicated that the local channel morphology has been modified by restoration <br />activities. There has been some sand-bar development adjacent to some of the inlets but there has also <br />been the shifting of sand bar away from the inlets. There is no evidence to suggest that levee removal <br />caused any of the changes that occurred in the main channel of the Green River. The changes that <br />occurred since levee removal are similar to the changes that were observed as part of channel monitoring <br />prior to level removal. The changes that were observed following levee removal are typical of natural <br />dynamic systems. The bar shifting documented near the restoration sites is typical of the local channel <br />morphology before restoration activities. Sedimentation in the bottomlands themselves has also. been <br />negligible. One other parameter, vegetation encroachment, has thus far not been a significantly negative <br />impact of the restoration activities. A significant amount of growth wa's noted in the inlets in 1997, but the <br />growth of this vegetation was not prolific in 1998. The continued flooding of these sites should keep <br />tamarisk growth in check, although some vegetation will continue to grow. Noxious weed growth and <br />tamarisk encroachment is quite common in the river corridor, and the growth experienced at the <br />restoration sites does not appear to be significantly worse and is even less evident than it is at many <br />locations in the vicinity. <br />• <br />• <br />