some degree of fluvial processes in order to promote ecosystem restoration. Rather than focusing on how they can help restore natural processes, however, the principal measure for ranking alternatives is “area affected”—a metric that is not well correlated with ecosystem function. Proposed restoration measures should be related more clearly to overarching scientific theories of river science and restoration.

Although the flaws and weaknesses summarized in this report are serious and of concern, they must be weighed in light of the challenges posed by this study. River science theories and research from the Environmental Management Program (EMP) provide useful guidance, as do river management efforts conducted elsewhere, but ecosystem restoration on the scale of the UMR-IWW is essentially unprecedented. Progress toward adaptive management on the UMR-IWW will require support and participation from parties beyond the Corps, including the U.S. Congress, other agencies, and river system users. The Corps has devoted a considerable effort to expanding and improving the study, especially in the last several years. One helpful outcome of this effort has been the development of a Preferred Plan that explicitly incorporates incremental implementation, based on continuing data collection, improved modeling techniques, and evaluation. If this plan is carried out as proposed in the restructured feasibility study, some of the problems noted in this report could be addressed through the application of methods of adaptive management. If so, the long-term prospects for the UMR-IWW could be a system that is managed and balanced in a way that provides even greater benefits to the nation.

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