Water Sustainability Assessment Under Climatic Uncertainty—A Case Study of Chhattisgarh (India)

Water sustainability and vulnerability in terms of economic, social, and environmental terms is a holistic concept that affects the society at large. Assessing water sustainability is a decision-making problem that involves multiple stakeholders and perspectives. Precipitation is one of the key parameters in water resources sustainability. In the present case study, techniques based on Standardized Precipitation Index (SPI) has been advocated for assessment of drought and non-drought conditions at regional level. These conditions are subcategorized into drought, near normal, and wet conditions, whereas near normal and wet conditions are considered as non-drought events. On the basis of long-term rainfall time series, the performance parameters such as reliability, resilience, vulnerability, and relative vulnerability are assessed and utilized for quantification of district wise water sustainability index (WSI). Finally, an overall WSI is estimated at the regional level using the distance-based approach on the basis of most pessimistic, most optimistic, and neutral approach. The proposed methodology is illustrated with the help of a real time case study for the state of Chhattisgarh in India. Further, in order to study the impact of climate change on drought conditions, two possible scenarios, i.e., HadCM3 A2 and B2 are considered to generate the future downscaled rainfall series. On the basis of the generated rainfall series and by using the proposed methodology, WSI for all the districts of the Chhattisgarh state has been assessed.