A Model for Integrated Water Resources Management in Water-Scarce Regions: Minimization of the Impacts of Groundwater Exploitation on Society and the Environment

Abstract

Israel is a developed, water-scarce country, with problems of increasing aquifer water salinity resulting from its exploitation of groundwater resources. To address this problem, we developed a model for planning water supply from diverse sources, including groundwater, the National Water Carrier, wastewater and seawater, and implemented it on two case studies in Israel. The model integrates hydrological, technological and economic considerations, and estimates the economic and environmental impacts of alternative water management policies. The hydrological model forecasts the concentration of chlorides in the aquifer under alternative scenarios in the short term and long term. The economic model estimates the costs of various desalination processes under the regional conditions, and the total costs of the water supply to the region under these scenarios. The conclusions are that desalination of brackish water involves lowest costs; desalination of National Carrier water is effective when there is large-scale use; desalination of wastewater is significant for maintaining the chloride concentration threshold in water for agriculture; and desalination of seawater is recommended when it makes an important contribution to maintaining the national water balance. Most importantly, we conclude that the economic cost of improving the quality of the supplied water and of the aquifer water should be considered in decision making.