THREE ESSAYS ON WATER MANAGEMENT IN AN ARID ENVIRONMENT

Abstract

This dissertation addresses the challenge of water scarcity in arid and semi-arid environments, where limited renewable resources, overexploitation of groundwater, and the impacts of climate change threaten long-term water security. The study first reviews a wide range of global strategies, including desalination, managed aquifer recharge, wastewater reuse, cloud seeding, virtual water trade, irrigation efficiency, crop selection, and economic instruments. While each approach presents technical, environmental, or social challenges, the literature shows that when properly regulated and adapted to local conditions, these strategies can effectively reduce pressure on freshwater resources. Building on this foundation, the research then turns to Saudi Arabia as a case study. An analysis of wheat imports from 2001 to 2023 demonstrates that virtual water trade has conserved 183.71 billion cubic meters of national water resources, including 139.62 billion cubic meters of nonrenewable groundwater, while also contributing to global efficiency by sourcing wheat from rain-fed regions. A second analysis of four key crops, dates, potatoes, tomatoes, and watermelons, shows that adopting modern irrigation techniques could save an average of 823 million cubic meters annually. Economic modeling further indicates that moderate water pricing and targeted tax exemptions can improve the financial feasibility of these systems, supporting wider adoption by farmers. The dissertation shows that addressing water scarcity in arid regions cannot rely on a single solution. A combination of strategies, such as relying on virtual water trade, improving irrigation efficiency, and applying supportive economic policies, is necessary to reduce pressure on groundwater and secure more sustainable water use.