A Perspective of River Basin Development

The river systems of the world flow today with only a small proportion of their total volume harnessed and applied for human good. With the exception of a few small drainage basins in arid regions, the water of no stream has been fully regulated or used. There are physical limits to such regulation and use, but the degree to which those limits are approached is related to conditions which are partly technological, partly economic, partly political, and partly ethical. Using the concept of integrated river basin development, each major network of streams draining the land masses of the earth may be viewed as the backbone for a possible planned use of a unified system of multiple-purpose and related projects to promote regional growth. This view of river basin development has come, during the past sixty years, to be employed rather widely as a technical tool for achieving social change. It has found imaginative support, and it appears to be on the threshold of wider application. How much further it wisely may be applied would seem to depend, in part, upon sharpening of our knowledge as to its utility and implications as a tool. Like any tool, it is not inherently good. Its value must be judged in terms of the growth and changes it can effect and upon its flexibility and precision. The concept of river basin development is used here to mean three component ideas having separate roots in western civilization but coming to be associated with each other in present-day theory and practice. In addition, at least two other ideas have been related in varying circumstances, and it now is possible to suggest a definition of the tool on which there is relatively common agreement in practice. Before examining the evolution of that concept, it may be helpful to identify the broad limits to river basin development and the distinguishing characteristics of river systems. A. Limits and Degrees of Development Although the Nile and Tigris-Euphrates Valleys cradled the early civilizations of the eastern Mediterranean and still support their basic irrigation agriculture, and although the flows of the Rhine, the Ohio, and the Thames long have been essential to the industrialized populations along their banks, it would be inaccurate to regard