Reservoir management decisions continuously strive to balance conflicting risks and benefits. Hydrologic uncertainty is a major complicating factor, especially during extreme events when data are sparse and probabilistic characterizations are less reliable. The set control approach offers an alternative by assuming that inputs are unknown but bounded. The solution provides a set of control actions which guarantee that the system will operate within the stated constraints for a certain time horizon. The method is applied to a three-reservoir system in the southeastern United States. ¿ American Geophysical Union 1993