MODELING FOR WATER-QUALITY DECISIONS - UNCERTAINTY AND SUBJECTIVITY IN INFORMATION, IN OBJECTIVES, AND IN MODEL STRUCTURE

Quantification and reduction of uncertainty associated to decision making is one of the primary functions of modeling and monitoring targeted to assist decision making in reservoir, river, and lake water quality management. In many practical activities such as environmental impact assessment, the inference is bound to be based primarily on subjective, expert judgments, supported by empirical data and models. A bulk of analytical approaches is presently available for modeling purposes. The paper discusses selected decision analytic approaches to the handling of uncertainty and subjectivity associated to information available, as a decision criterion, and as a component influencing the model structure. Computational solutions based on experience on seven case studies are reviewed.