recreational uses of the downstream reaches of the watershed. Accordingly, federal and state regulations consider sediment to be a pollutant, despite the fact that it is a natural component of functional rivers. Many chemical pollutants adhere to the surfaces of sedimentary particles, so that sediment-rich discharges usually carry higher loadings of pollution than water alone. The sediment itself also poses problems for the physical integrity of streams because it fills downstream reservoirs, consuming space that was originally designed to store water. Sedimentation in channels alters their configuration and destabilizes them, making management and use more difficult as well as increasing their flood potential as channel capacity is reduced. Sedimentation also affects fish by silting over gravel beds necessary for spawning and covering benthic organisms important in the food chain.

Navigation

Many American waterways serve as transportation corridors for large quantities of bulk goods. For instance, the Ohio, Missouri, and Mississippi rivers have huge upstream service areas to ocean ports and carry barge traffic of coal, grain, natural gas, and other bulk commodities. The system of dams and locks that makes this commerce possible requires a consistent flow of water made possible only by basinwide management. On the Columbia River system, and many others, barge traffic must compete for management attention with fisheries, recreational, and hydroelectric objectives. The resolution of such competition among uses must take into account local as well as national interests.

Economic Development with Hydroelectric Power

The United States has long used watershed management to accomplish economic development goals, primarily but not exclusively in the West. That is, we have used construction of large dams and associated structures to provide water and water-dependent services (e.g., drinking water, irrigation water, and power) to our citizens, first to encourage people to settle the West and through time to sustain the farms and industry of western communities. Hydroelectric power generation is a classic example. At least two large efforts—the Tennessee Valley Authority (TVA) in the southeast and the Bonneville Power Administration (BPA) in the Pacific Northwest—originated during the Great Depression and were part of a vast federal initiative to restore economic vitality. The spirit of these programs was captured in the words of folk singer Woody Guthrie, who in 1941 wrote the following on commission for BPA about the new Columbia hydropower system (Lee, 1993):

. . . roll along, Columbia, you can ramble to the sea,

But river, while you're rambling, you can do some work for me.

. . . Lots of folks around the country,



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