The River Basin Model is not primarily a water management model. Through human interaction and computer simulation, it represents the entire complex economic, social, and governmental activities taking place within a specified local system. The manual contains the basic information and description of the model required by the social sector. It is assumed that the Model Overview and the Scenario descriptions have been read prior to the receipt of this manual. Once the players comprising the Social Sector have become familiar with the model in general, the particular city being represented, and the workings of the local economic, social, and government system they will be able to bring their own imagination and initiative to bear on the operation of the Social Sector and the population groups they represent.

Predictions of the complex annual cycle of temperature changes in a lake or reservoir are necessary if proper water quality control is to be achieved. Many lakes and reservoirs exhibit horizontal homogeneity and thus a time-dependent, one-dimensional model describing the temperature variation in the vertical direction is adequate. A discretized mathematical model was developed based on the absorption and transmission of solar radiation, convection due to surface cooling and advection due to inflows and outflows. The model contains provision for simultaneous or intermittent withdrawal from multi-level outlets and time of travel for inflows within the reservoir.