Screening Water Supply Options for the Edwards Aquifer Region in Central Texas

Abstract

A screening model is developed to support the selection of alternatives for meeting future water demands and protecting sensitive ecosystems in the Edwards aquifer region of central Texas. Important attributes of the model are its basis on existing ground- and surface-water simulation models and its incorporation of uncertainty in future supplies and demands. The model is used to evaluate trade-offs involving environmental and economic risks and to identify water resources alternatives that promise to be robust (i.e., those that can be managed in a flexible manner to meet society's goals under a wide range of hydrologic scenarios). Use of the model to help determine conjunctive surface- and ground-water management policies is also demonstrated. Although limited benefits can be obtained through more coordinated operation policies, results indicate that either large investments in infrastructure or substantial reductions in projected water use will be required to meet environmental goals with a high degree of reliability.