Drought Storage Allocation Rules for Surface Reservoir Systems

Abstract

This technical note develops a simple drought storage allocation rule to minimize evaporative and seepage water losses from a system of reservoirs. Such a rule might have value during a prolonged drought, when the value of lost water is likely to be particularly high. Typically, concentrating water storage in one or a few reservoirs reduces overall water losses compared to “balancing” storage among reservoirs. Paradoxically, concentrating storage during a drought tends to minimize reservoir surface area available for recreation, increasing recreation losses even as it minimizes water losses.