Geotechnologies in the identification of areas suitable for the construction of underground dams in the Brazilian semiarid region

Abstract

The Brazilian semiarid region faces water challenges that directly impact its agricultural activities. The municipality of Capoeiras, in Pernambuco, has great productive potential, but depends on sustainable water collection and storage strategies to overcome scarcity and ensure the continuity of local agriculture and livestock farming. Given this scenario, this research was developed with the objective of identifying and characterising potential areas for the implementation of underground dams (UDs) in the municipality of Capoeiras, Pernambuco, using geotechnologies. Individual maps were drawn up considering terrain, geology, soils, and hydrology, resulting in a general map of the region's suitability, using geoprocessing, remote sensing, and open-source software. The overlapping of the layers revealed different levels of suitability for the study area: 10.29% of the territory has high potential for the implementation of underground dams, while 31.39% has moderate potential, requiring more detailed planning. In contrast, 58.32% of the territory was classified as having low potential and was considered a restricted area according to the criteria adopted in this research. Field analyses and observations are essential to confirm the real potential for implementing UDs, contributing to more sustainable and economically viable water planning. The installation of water collection and storage technologies, such as BSs, tends to be more efficient in areas close to watercourses, especially where gentle slopes predominate, which favor the infiltration process. Local soil and climate conditions require territorialized water planning that incorporates continuous monitoring of rainfall and environmental dynamics in order to support public policies aimed at strengthening family farming in the municipality.