Application of AHP method to make underground water favorability model

Abstract

The location of wells in fractured aquifers is complex due to the difficulty of finding water in these media, characterized by high heterogeneity and anisotropy. There are several methodological proposals that aim to find favorable areas for water production in these aquifers, which usually involve geological and geomorphological conditions. In the present work, we intend to define an underground water favorability map for an area north of the Quadrilátero Ferrífero (MG) by integrating lithological, slope, HAND (Height Above Closest Drain) maps and morphostructural, magnetometric and radiometric lineaments. For this, we adopted the AHP method (Analytic Hierarchy Process), which allows the integration of various information planes in a less subjective way. The favorability map, validated with specific capacity data from 361 tubular wells, showed that the most relevant conditioning factors are in descending order, HAND, slope, lineament density and lithology. With the results, a groundwater favorability model was created for the study area, which can be tested in other similar regions.