Water demand around the world is likely to rise throughout this century, potentially increasing demand-driven water stress. Researchers at the U.S. Department of Energy’s Pacific Northwest National Laboratory explored where demand-driven water scarcity might emerge in the future and what responses could be expected in different water basins. They found that responses were quite robust across different water demand scenarios and could be grouped into three categories: limited response, reductions in electricity sector water withdrawals, and reductions in both electricity and agricultural withdrawals.
The key finding of this paper is that there is a consistent order to the response approach that different regions might take when faced with water scarcity, at least with regard to the electricity and water sectors. This result, along with the typology of water stress responses developed by the research team, will be valuable for future research exploring global water scarcity due to both demand and supply drivers.
This research explored regional response strategies to potential water scarcity driven by a wide range of alternate water demand scenarios. Using GCAM, an integrated human-Earth system model, the research team created a typology that categorized countries and basins according to how their electricity and agriculture sectors responded to increasing water demands. In many basins, little response was observed because water demands did not increase enough to create scarcity. An electricity-focused response was observed in most basins in Western Europe, the United States, and China, typically characterized by a transition to water-saving cooling systems. Finally, in areas with a lack of sufficient response capacity in the electricity sector (e.g., Pakistan, the Middle East, and several basins in India), the most notable response was observed in the agricultural sector, in which many regions reduce irrigation water withdrawals in response to scarcity, (e.g., switching from domestic production to imports). These regional responses were quite robust across the range of water demand scenarios tested.