The Project for the Integration of the São Francisco River with the Hydrographic Basins of the Northern Northeast represents a strategic intervention for the water security of the Brazilian semi-arid region. This study aims at the geoenvironmental characterization of the municipalities of the states of Rio Grande do Norte, Ceará and Paraíba benefited by the Apodi Branch (North Axis). The methodology was based on the integration of physical and socioeconomic data in a Geographic Information System (GIS) environment, using official databases from IBGE, MapBiomas, ANA and INPE, at the scale of 1:250,000. The results indicate a predominance of Paleoproterozoic crystalline rocks (≈60%), flattened reliefs associated with the Sertanejo Plateau and the Sertaneja Depression (≈65%) and soils with high agricultural potential under irrigation, especially Ultisols and Luvisols, which add up to 74.6% of the area. Land use is marked by the strong presence of savanna formations (54.9%) and pastures (30.9%), while urbanized areas represent 0.6%. Climate variability is significant, with average annual rainfall ranging between 652 mm and 1,709 mm, reinforcing regional water vulnerability. From the socioeconomic point of view, the municipalities have an average MHDI of 0.627, with marked inequalities between dynamic, intermediate and vulnerable locations. It is considered that the simple availability of water does not guarantee regional development, and it is necessary to articulate the transposition to the policies of territorial planning, environmental conservation and social inclusion. It is concluded that the integrated geoenvironmental characterization is an important instrument to guide the sustainable use of transposed waters, reduce historical vulnerabilities and promote a balanced and resilient territorial development in the northeastern semi-arid region.




