Spatial Variability of Rainfall and Vulnerability Assessment of Water Resources Infrastructure for Adaptive Management Implementation in Ceará, Brazil

Given that a robust water resource management strategy requires the knowledge of natural and climatic factors and social and economic factors, we applied a variability and vulnerability assessment as a quantitative tool to characterize water resources in Ceará, Brazil. A methodological approach that identifies and quantifies variability and vulnerability would allow better solutions to management decision problems. This approach functions as an indicator-based framework separating areas with similar water availability and water resources infrastructure, indicating the influence of natural and anthropogenic factors in the area’s water resources. The assessment proceeded with the regions’ delimitation, classifying them according to rainfall amount and spatial variability. The Adaptive Capacity for Water Management Index (ACWM) was evaluated using georeferenced water infrastructure information based on that classification. Most of the state’s area is subjected to low rainfall (below average). Nonetheless, of the areas with low rainfall, 48% have high variability. Within those areas critical water infrastructures are located that supply water to the state’s main industrial and populated city. Thus, the acknowledgment of this characteristic can complement current water management. Lastly, the authors provided recommendations based on the coupling of variability and vulnerability assessments with adaptive management to address improvements in the current water allocation system.