Practical application of probabilistic approaches to the management of water resource systems

Sophisticated stochastic optimization and simulation methods to assist with the management of large water resource systems in South Africa were developed and rigorously applied during the last decade. Acceptance today is not only due to the sound theory underpinning the methodology and the successes achieved with respect to improved resource utility, but also because of efforts to communicate findings to decision makers and interested and affected parties. Credibility was further enhanced by a number of practical applications where decisions based on information provided by the models led to substantial cost-savings. The paper gives an introductory perspective of water resource systems modelling in South Africa. Concepts of yield, together with probabilistic approaches to assess the yield characteristics of water resource systems, are described. Reference is made to different practical applications of the methodology.