Modeling Integrated Decisions for a Municipal Water System with Recourse and Uncertainties: Amman, Jordan

Stochastic mixed–integer optimization is used to identify a portfolio of long– and short–term supply and conservation actions for a municipal water system to cost–effectively accommodate a distribution of water shortages. Alternative robust, grey–number, and best/worst case formulations systematically explore implications of uncertainties in action costs, life spans, water volumes gained or saved, shortage levels, and shortage probabilities. A detailed example for Amman, Jordan considers 23 potential actions. Results show: (1) remarkable consistency occurs across the different modeling approaches. (2) Conserving water‘reducing leakage and targeting select customers to install water efficient appliances’plays an important and growing role over time. (3) A delayed need for large supply projects like pumping the Disi aquifer. (4) No role appears for seawater desalination (Red–Dead Canal) before 2040. (5) Desalinating brackish Zara–Ma'een water is the low–cost option to increase water availability to customers but requires substantial capital investments. And (6) two shortcomings arise for grey–number and best/worst case approaches.