RESUMO
The lack of perennial streams or surface water in most arid countries necessitates input modification and water scarcity/security equation calculation as per the water resource systems and physiographic conditions in these countries. The contributions of nonconventional and virtual water resources to water security have been disregarded or undervalued in previous research on global water scarcity. This study addresses this knowledge gap by developing a new framework for estimating water scarcity/security. The proposed framework considers the contributions of unconventional and virtual water resources and the roles of economics, technology, water availability, service accessibility, water safety and quality, water management, and resilience to threats on water and food security, and considers institutional changes required to adjust to water scarcity. To manage water demand, the new framework incorporates metrics for all categories of water resources. Although the framework was specifically designed for arid regions, particularly the Gulf Cooperation Council (GCC) countries, it is applicable to non-arid nations too. The framework was implemented in GCC countries, which are suitable examples of arid countries with notable virtual commerce. The ratio of abstraction from freshwater resources to renewability from conventional water sources was calculated to determine the extent of water stress in each country. The values obtained from measurement varied from 0.4 (the optimal threshold level for Bahrain) to 22 (severe water stress/low water security in Kuwait). Considering the nonconventional and abstracted nonrenewable groundwater volumes from the total water demand in the GCC, the minimum water stress value measured was 0.13 in Kuwait, suggesting considerable reliance on nonconventional water resources along with little domestic food production to achieve water security. The novel water scarcity/stress index framework was found to be appropriate for arid and hyper-arid regions, such as the GCC, where virtual water trade has a major positive impact on water security.
