A spatial application of the water poverty index (WPI) in the State of Chihuahua, Mexico

The Water Poverty Index (WPI) standardizes water scarcity diagnostics by considering natural, environmental, and socioeconomic factors which reduce, facilitate, or prevent water access. To integrate these factors, the WPI includes five components: resource, environment (negatively affected by development), capacity, access, and use (positively affected by development). Nevertheless, the place granted to hydrological factors is questioned, and many studies insist on the problematic correlation of WPI with the well-known Human Development Index (HDI). Calculating WPI in the socially heterogeneous and semi-arid context of the State of Chihuahua (Mexico), adapting traditional methodology thanks to geographic information systems (GIS) tools and the corresponding databases, allows discussion of those points. This study uses multi-criteria evaluations from TerrSet software to calculate WPI while preserving specific data precision. In this process, scale calculation and indicator normalization are adapted through raster maps and fuzzy techniques to valorize specific hydrological data. This opens interesting discussions for multidimensional water scarcity diagnostics, since they increase the visibility of diverse water scarcity issues in WPI results. In fact, concentrating socioeconomic factors in corresponding components and valuing GIS alternatives provides a diagnostic different from the HDI and sensitive to hydrological factors.