How to carry out an optimal expansion of an existing water resources
system is of continuing importance because of the rising demand for and
limited supply of water in many areas of the world, particularly in the
southwestern part of the United States of America. Governmental agencies in
the U.S.A. and elsewhere have made large public investments in the field
of water resources in the past and will continue to do so in the future.
Whenever investment in a water resource project is under consideration,
important questions such as what is the economic value of the project(s),
what is the optimal scale of development of the project(s), and when
should the project(s) be constructed need to be answered. It is only through
the use of an analytical economic evaluation that competitive uses for
capital can be quantitatively evaluated.
This monograph describes a methodology that can be used in water
resources planning taking into account both water quantity and quality
while still remaining computationally tractable. It is concerned with the
optimal expansion of a realistic water resources system to meet an increasing demand for municipal and industrial use, irrigation, energy, and
recreation over a planning horizon of T mAX years. Although the problem of
quantitatively describing a water resources system in a realistic fashion is
forbidding, the outlook for quantitative analysis is good. Some of the
problems of describing a river basin include:
1. We have only a fragmentary knowledge of the relevant parameters to
include in a river basin model.
2. We do not know how important some of the variables are in relation
to others.
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