A dynamic-stochastic model of a reservoir and municipal water system has been developed and studied. The overall structure of the model, which is written in Stella?, is presented; the physical- environmental- and end- use- segments are outlined and sample simulation results are presented. The flexibility of the model to encompass physical changes in the system is highlighted. Alternative representations of end-use are outlined and the applications of this type of modeling for policy analysis and water resources management is suggested. The design and status of on-going studies to validate key components of the model are discussed.