An Introduction to Optimization Models and Methods

Abstract

Water resource systems are characterized by multiple interdependent components that toge- ther produce multiple economic, environmental, ecological, and social impacts. As discussed in the previous chapter, planners and managers working toward improving the design and per- formance of these complex systems must identify and evaluate alternative designs and operating policies, comparing their predicted performance with desired goals or objectives. Typically, this identification and evaluation process is accom- plished with the aid of optimization and simula- tion models. While optimization methods are designed to provide preferred values of system design and operating policy variables—values that will lead to the highest levels of system performance—they are often used to eliminate the clearly inferior options. Using optimization for a preliminary screening followed by more detailed and accurate simulation is the primary way we have, short of actually building physical models, of estimating effective system designs and operating policies. This chapter introduces and illustrates the art of optimization model de- velopment and use in analyzing water resources systems. The models and methods introduced in this chapter are extended in subsequent chapters.