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examples of such degradation below other dams. They concluded that the process begins with dam closure. occurs at a fast pace for the first few years. then slows with time until the bed is "armored" with material too coarse to be moved by the river. or until a bedrock control is exposed. This time.dependent process moves downstream as progressively more sediment is lost from the system, Will Hells Canyon ever recover its beaches? Probably not in our lifetime. Alternative management scenarios for minimizing erosion exist but they all have significant drawbacks. The least sophisticated alternative would be to simply dismantle the three dams. To be realistic. the dams in Hells Canyon are not among that handful of candidates for Sandbar an the Snake River in Hells Canyon removal. Alternatively. even though the Hells Canyon reservoirs are relatively small. they could be managed primarily for flood control rather than for hydro. electric power. The reservoirs would be kept as close to empty as possible. and floods would be released as slow steady flow into Hells Canyon. The beaches might erode more slowly. but riparian vegetation would colonize the remaining fine'grained substrate. But this would cost Idaho Power Company (more precisely Idaho Power Company's customers) millions of dollars in lost revenues. Such a flow regime could engender its own set of downstream problems. such as the invasion of vegetation along the river banks. Another option would be to some- how pass sediment through the dams. Idaho Power Company could devise a way to transport sediment around its turbines. thereby preserving the useful. ness of its dams and simultaneously reintroducing sand to the sediment. starved reaches of the Snake River in 26