VARIABILITY IN PERCEIVED SATISFACTION OF RESERVOIR MANAGEMENT-OBJECTIVES

Fuzzy set theory provides a useful model to address imprecision in int erpreting linguistically described objectives for reservoir management . Fuzzy membership functions can be used to represent degrees of objec tive satisfaction for different values of management variables. Howeve r, lack of background information, differing experiences and qualifica tions, and complex interactions of influencing factors can contribute to significant variability among membership functions derived from sur veys of multiple experts. In the present study, probabilistic membersh ip functions are used to model variability in experts' perceptions of satisfaction of objectives for hydropower generation, fish habitat, ka yaking, rafting, and scenery preservation on the Green River through o perations of Flaming Gorge Dam. Degree of variability in experts' perc eptions differed among objectives but resulted in substantial uncertai nty in estimation of optimal reservoir releases.