ABSTRACT
Owing to the fact that most of the classical drought indices focus on the current status of rainfall deficit, the Reliability-Resilience-Vulnerability (RRV) concept has been recently adopted by a few researchers for the characterization of long-term droughts. This chapter provides a brief review on application of the RRV concept in water resources planning and management, followed by a case on application of the RRV concept on developing a framework for assessing groundwater quality. Stability of a groundwater quality parameter is a measure of its variability over time. A framework based on three probabilistic terms, i.e., reliability, resilience, and vulnerability, is developed to assess stability of the groundwater quality. The framework is helpful in understanding the changes occurring in concentration of a particular groundwater quality parameter over a given period of time. Three probabilistic terms require a threshold value of the parameter to decide successful and failure events, and also to take a difference of the observed and threshold values for that parameter. Thus, the desirable and/or permissible limits suggested for drinking water, prescribed by the World Health Organization, Geneva, are used as threshold values for the parameters while computing a stability index. The proposed stability index is developed based on the “system-robustness” and “system sustainability” criteria, and it integrates two important probabilistic characteristics of the groundwater quality, i.e., reliability and resilience. Furthermore, a case study is demonstrated where the developed stability index is computed for a quaternary alluvial and quartzite aquifer system located in Jaipur district of India. The stability index proposed in this study has the added advantages of having statistical framework, consistency (free from subjectivity), and comparability over different parts of the world. The values of the stability index indicate temporal stability of the groundwater quality, and this characteristic of the stability index enables its applicability for the multi-year groundwater quality dataset. The index remains free of subjectivity as weights are not assigned to different parameters considered for the analysis. Overall, the RRV-based stability index can be proved as an excellent probabilistic indicator of groundwater quality over different parts of the world.
