ABSTRACT
In the drier climates water was used for irrigation, in wetter, low-lying areas later drainage schemes made the land habitable. Water is also managed for a great variety of industrial purposes, for recreation and for its natural beauty in the landscape, all of which require maintenance of water quality and control of pollution. The oldest of water rights is the riparian doctrine, which was part of the civil law of Rome and later became incorporated in the common law of England. Two major concepts in water-resources management have helped to emphasize the need for improved allocation techniques: those of multi-purpose use and of integrated river-basin development. In an interrelated multi-purpose water-resources system the evaluation of its component functions in precise economic terms is rendered more difficult on account of the highly intricate economic relationships and the spatial linkages involved. One method of evaluating collective benefits on an economic basis is to calculate the least-cost alternative to provide the same supply.
