USE OF THE IDW INTERPOLATION METHOD FOR THE MAPPING OF FLOW AND ELECTRICAL CONDUCTIVITY OF GROUNDWATER IN THE STATE OF CEARÁ

ABSTRACT Water scarcity in semiarid regions requires the efficient management of groundwater for population growth and regional development. Evaluating the flow rate variability and electrical conductivity (EC) of deep wells is crucial because these parameters indicate the availability and quality of water. This study aimed to map the spatial distribution of these data in the state of Ceará via information from the Geological Survey of Brazil and the inverse distance weighting (IDW) method. A total of 6,018 flow data points and 9,434 EC data points were used for interpolation in SAGA software. The mean flow was 5.45 m3/h, and the EC was 2.21 dS/m. An exponential semi-variogram was the best model for spatial interpolation. Geomorphological factors, aquifer types and environmental conditions influence the distribution of parameters. Regions with more weathered soils presented greater water storage potential. The Salgado, Baixo Jaguaribe and Coreaú Basins had the highest quantitative groundwater potentials. It is concluded that the methodology used is effective in guiding public policies and water management strategies.