There are several competing hypotheses and models regarding the effects of environmental factors on Columbia River Salmon. The relative importance of various environmental variables on salmon smolt survival is not clearly established. Nevertheless, the reprot notes that when river flows become critically low or tempertures excessively high, pronounced changes in salmon migratory behavior and lower survival rates are expected. It is recommended that if additional water withdrawal permits are issues, that they include conditions that allow withdrawals to be discontinued during periods of high demand, low flows, and comparatively high water temperatures. A join, basin-wide forum, to be convened to discuss the environmental consequences of proposed water diversions, is also recommended. The report advises the State of Washitngon and other basin states to continue to explore the prospects of water banks and other market-based mechanisms for moving water to higher-value uses. It was noted that sound salmon management staretegies will depend not only on scientific input, but also on willingness by elected leaders and appointed managers to take actions in the face of uncertainties.
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