Environmental Vulnerability Assessment of Anthropogenic Droughts in Regulated Basins

Abstract

Man-made local water supply infrastructure (in particular reservoirs) affects future water availability because it is built specifically to cope with climatic extremes. A system with multiple reservoirs, and therefore more local resilience, will be less vulnerable to climatic change and variability compared to a system with limited local capacity to cope with extremes. Therefore, different regions will see different water availability changes depending on their local infrastructure and capacity to cope with variability or adapt to change. The key questions that are studied in this proposal is the extent and intensity of environmental impact of the water stress. To address the question, this study proposes a multidisciplinary framework that integrates top-down (local inflows) and bottom-up (historical water use categories) factors to quantify the human induced water stress in each reservoir and the overall impact on the system’s resilience (water availability). The human induced water stress in regulated basins (with multiple reservoirs) is tracked by assessing the historical water use categories, which are later used to develop hypothetical water demand scenarios for near-future water stress assessment. Recent studies have shown that by changing water use policies, the system builds up resilience to cope with water stress. Our study explores reservoirs with multiple basins and tracks the policy changes impact on the system regarding the reservoirs orientation in the basin. Furthermore, this study tracks the environmental impact of the socioeconomic drought condition in regulated basins and highlights the changes due to water use policies.