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2. Formulating
the
Problem
Fig. 2.1 Elements of a hypothetical river basin.
basin as illustrated in Fig. 2.1. Each subsystem of the river basin has
definite demands on and consumptions of water. A forecast of increasing
demand for municipal and industrial use, irrigation, energy, and recreation
is available over a planning horizon of r ma x years. Because the existing
river (canal) and flow regulation facilities are operating at near optimal
levels, it is presumed that these facilities will not be adequate to meet
future demands.
A number of possible dam sites are available for the further regulation
of river (canal) flows in the basin and/or the regulation of waters imported
into the basin. Each dam can be built to several scales; each scale is considered a separate project. With each dam is associated a capital cost and
an annual return associated with its optimal maximum use. The planner is
concerned with what projects to undertake and when to undertake them.
A capital budgetary constraint exists.