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examples of legislation and executive actions contributing to multiobjective approaches and some multiobjective applications. It considers the role of riverine wetlands in multiobjective management. Next, trends in river corridor management are considered including factors leading to the application of multiobjective approaches. Finally strategies and recommendations for multiobjective management are provided. The paper focuses upon the United States, but much of the discussion and many of the recommendations may be equally applicable elsewhere. TRADITIONAL RIVER ENGINEERING Traditional river planning and "engineering" approaches continue to be used to address many flooding, navigation, water quality, and erosion problems on rivers and streams in the U.S. and throughout the world. These engineering approaches focus primarily on the river channel and bank area and involve the construction of various dams, reservoirs, dikes, levees, channel straightening, channelization, and other man-made structures to modify natural river and stream flooding and erosion regimes and utilize river and stream waters for the activities of man. In a report written in 1972, it was estimated that 235,000 miles of streams and rivers had been channelized in the U.S. alone (Wilkinson 1972). Usually engineering projects are designed to serve a single predominant objective -- flood control, water supply, or pollution control -- although projects designed to serve several objectives are also common. But, whether single objective or multiple objectives, the engineering "project" approach generally favors river and stream channel and/or floodplain modification to achieve the project's goals. Classic engineering approaches have been quite effective in at least temporarily achieving many specific flood control, erosion control and other goals for particular reaches or segments of rivers and streams and no doubt will continue to be used quite broadly. But, they often do not adequately consider fish, waterfowl, and other habitat values and the functioning of broader ecological systems; the result is the loss of many natural values and functions (see Klimas, Hesse, Nelson et al., many other papers this volume). Quite often they are designed without adequate consideration of long term hydrologic and geomorphological processes such as sediment regimes, making them vulnerable to sedimentation or accelerating upstream or downstream erosional processes as a river or stream attempts to return to an equilibrium stream profile (Hesse, this volume). And, construction and maintenance costs are substantial. For example, the U.S. Water Resources Council in 1977 estimated that expenses for flood control and prevention works had averaged over $600 million a year for the preceding ten years (U.S. Water Resources Council 1977). E.P.A. estimated in 1988 that an unbelievable 400 billion dollars had been spent in the 1972-1986 period for water pollution abatement and control measures by government and industries (E.P.A. 1990). In short, such approaches may not, in the long run, be the most cost effective for achieving a broad range of goals. Rivers and streams and their adjacent wetlands and floodplains continue to be the most heavily impacted of the three major surface water systems on earth -- oceans, lakes, and rivers and streams. Oceans and estuaries have, to some extent, been polluted and filling has occurred along their shores. Water levels in major lakes have often been partially stabilized and waters have, in some instances, been polluted or subjected to eutrophication. But rivers and streams have been subjected not only to major point and nonpoint source pollution but to broadscale flow modifi- cation for water supply, irrigation, development purposes, flood control, and recreation (see many papers in Chapters 1 and 2 of this volume and Table 1). The channels and banks of rivers and streams have been widely dredged and straightened for navigation and flood control and in some instances "hardened" with concrete to reduce erosion and meander. The floodplains and wetlands, which serve as flow channels during high water, have been widely modified and utilized for agriculture, commercial, and industrial purposes. Table 1 IMPACTS TO RIVER CORRIDORS Dams Dikes, Levees Channelization Dredging Bank Stabilization Fills Water Diversions Gravel Mining, Placer Mining Piers, Docks vegetation Removal (Forestry, Agriculture, etc. Grazing Point and Nonpoint Source Pollution Agriculture and Forestry Activities Residential, Commercial, Industrial Development it is no surprise that the natural pollution control, fishery, food chain support, wildlife, flood storage, flood conveyance, recreation, and other natural functions and values of both the rivers and adjacent wetlands have been damaged or destroyed by these modifications (see many papers, this volume). Once destroyed, these functions and values must often be replaced through flood con- trol measures, erosion control measures, waterfowl impoundments, or pollution control facilities. The predominant landowner and government goals for management of rivers and adjacent lands have changed in the last two decades (Table 2), particularly in developed nations such as the United States. At one point, rivers and streams were the major transportation systems. These were replaced by railroads and roads. At one time, riverfront lands were the major sites for industrial development. Now, rivers and stream corridors are often considered prime recreation, park, parkway, residential subdivision (where the flood threat is not too great), and commercial waterfront development sites (e.g., small shops, waterfront malls, etc.) 4