The groundwater risk index: Development and application in the Middle East and North Africa region

Highlights: • Developed a Groundwater Risk Index (GRI) as a multidisciplinary diagnostic tool • GRI is a function of hydrological models and political and socioeconomic factors. • Groundwater allocations are indeterminate of groundwater depletion risk. • Groundwater depletion risk is determined by governance and food security levels. • GRI's flexible design enables its modification and application in other regions. Overreliance on predominantly non-renewable groundwater resources and their subsequent depletion has given rise to adverse environmental, political, economic, and social effects. The high costs of groundwater depletion are exacerbated by the notable absence of tools designed to identify and diagnose areas at risk of groundwater degradation. In this study, a Groundwater Risk Index (GRI) was developed as a distributed composite index to assess and evaluate groundwater depletion risk by combining different environmental and socioeconomic datasets and models. GRI is designed to be used by end-users (e.g. governments, NGOs) as a multicriteria diagnostic tool to identify and determine the probability and severity of an entity experiencing the adverse effects of groundwater mining. Annual GRI results indicate that groundwater risk is highly dependent on governance and food security. Surprisingly, groundwater storage reserves were indeterminate of groundwater risk. Given the centrality of agricultural production in groundwater consumptive use, MENA countries are recommended to mitigate groundwater depletion by establishing reliable and secure virtual water transfers (agricultural trade) to achieve food security, as opposed to unsustainably exploiting finite water resources for short-term food sufficiency. The GRI's design choices, including adopting an equal weighting scheme and a linear additive aggregation approach, promote structural flexibility that enables the modification, application, and implementation of the index in other semi- to hyper-arid regions with a high level of dependency on groundwater resources.