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I .1 . J 9 the loss of side channels, backwaters, and oxbows (Li et aI., 1987). Babinski (1992) documented the loss of islands and mid-channel bars and a 50% decrease in channel width on the Visula River, Poland due to bank stabilization. Similar channel narrowing was reporte~ by Wyzga (1993) on the Raba River in Poland. On the upper Colorado River, bank stabilization also affects channel morphology in some areas. ';! ..\ ,..,1 . .j l J j 1 ] P} .1 J ] I PROPOSED SOLUTIONS Once a river has been changed by water development, nonnative fishes and vegetation, and bank stabilization, it is unlikely that it will ever return to its pristine state. Removal of dams and diversions is usually not a practical solution when political and economic impacts are considered. Similarly, the removal of nonnative fishes and vegetation is not \riable I ) since it is essentially impossible to extirpate them on a basin-wide scale, and even if it were possible, re-colonization from adjacent drainages would be inevitable. However, efforts are underway to develop river management plans which promote natural conditions and the recovery of endangered fishes. The most viable solution for restoring a river towards its original character is by managing water releases from dams. This is usually termed "flushing flows" and can help maintain the natural character of a river on a regional scale. Flushing flows can remove fine sediment from spawning sites, disrupt riparian plant communities, change channel morphology (Reiser and Ramey, 1985), and select against nonnative fishes since many species are unfit for surviving high flows (Minckley and Mefee, 1987). When flushing flow recommendations are made, it is important that they are based on data from the specific river and reach in question