Access to drinking water remains a major challenge in the Democratic Republic of Congo, particularly in Kinshasa, where rapid population growth exerts intense pressure on existing water infrastructure. In response to this crisis, the population of the Lemba Commune is turning massively to groundwater through an uncontrolled proliferation of individual boreholes, often drilled without adhering to the recommended spacing standards. This situation raises critical issues related to the sustainability of water resources, the stability of aquifers, and environmental quality. This study employs Geographic Information Systems (GIS) tools to map the spatial distribution of more than 202 boreholes and analyze their hydrogeological and environmental impacts. The results reveal an excessive densification of extraction points, with distances sometimes reduced to 10-20 meters instead of the regulatory 150 meters, promoting overexploitation of aquifers, anthropogenic pollution, soil subsidence, and degradation of local ecosystems. Furthermore, the pressure exerted during drilling operations can induce local seismic risks, while the decline in groundwater levels compromises access to drinking water and resource quality. This study highlights the importance of integrated and sustainable management of groundwater resources, supported by a dynamic GIS database, strict regulatory policies, and increased public awareness. By combining scientific expertise, geomatics technologies, and political will, it is possible to ensure the sustainability of urban water resources, which are essential for socio-economic development and environmental preservation in a rapidly expanding urban context.

The cartographic and petrographic study of the Ntoni region, located in the Mbanza-Ngungu territory in Kongo Central province (DRC), aims to characterize and map the local geological formations. The methodology combines a documentation phase, a geological survey in the field, and microscopic analyses in the laboratory. The materials studied are mainly sedimentary rocks including limestones, dolomites, sandstones, and shales, whose limestone facies are classified according to Folk (biomicrites, intrasparites, intramicrites, biosparites, biopelsparites). The region benefits from a Sudanese climate and a varied relief, with a geological context dominated by the Neoproterozoic Inkisi group, composed of alternating schistose-sandstone and limestone terrains. The study made it possible to specify the lithology, spatial distribution, and depositional environment of the rocks, which vary between marine and continental settings depending on geological periods. An updated geological sketch was produced, showing significant stratigraphic complexity. This work enriches the geological knowledge of Kongo Central by providing a better understanding of the sedimentary formations, with implications for mineral resource exploitation and land use planning. It paves the way for more in-depth research on regional stratigraphy and tectonics.