This study focuses on the departments of Yamoussoukro and Toumodi located in central Côte d'Ivoire where the problem of drinking water supply is a growing reality. Its objective is to map and analyze the fracturing likely to develop underground aquifers from Landsat 8 OLI data. The set of techniques (color composition, directional and gradient filters) used resulted in the enhancement of linear structures present on satellite images, allowing a better mapping of geological features. The linear map obtained, after the different treatments, is very dense and includes 2063 lineaments. The validation of these different linear structures was made on the basis of the drillings already carried out, from the data of the geophysics. The analysis of the fracture networks has highlighted two dominant directions which are N0°-10° (N-S) and N90°-100° (E-W) highlighting the heterogeneity of the geological formations. These results constitute an essential contribution to the exploitation of groundwater resources in the departments of Yamoussoukro and Toumodi.

The supply of drinking water from aquifers of base remains problematic because of his complexity. The combination of several methods is more adapted for the mapping of water establishment favorable areas. This study is focused on water points establishment favorable areas mapping. The methods used are remote sensing, pump tests sheets for determining aquifers and saprolites thickness. To determine the recharge, GR2M Method and drainage density has been used. The digital elevation model (DEM) has been used to generate slopes and drainage density maps. The thematic maps obtained combined under GIS to produce water potentiality map. The results obtained have been with exploitation rates. Three classes of potentialities have been identified. These are classes of high potentialities in groundwater which cover approximately 20% of the study area. It occurs mainly in central areas where there are sedimentary formations usually captured by the drilling. These areas are generally located in the central part, mainly in areas where there is low slope, important with a thick layer of saprolites.

Water is an indispensable resource for all activities developed by man. Water resources are indispensable for the survival of the populations of the Lobo watershed in Nibéhibé. They offer many multidimensional services. Around these important resources, social actors have different ways of perceiving them. This is why their management comes up against a difference in logic and action on the part of the different stakeholders. Thus, it must be noted that there is a crystallization of social relations between the different groups of actors involved and this is based on conflicts of use and the intensity of water scarcity. The objective of this study is to show the relationship between management mode and conflicts of use of water resources in the Lobo watershed in Nibéhibé. To achieve this objective, the methodology was based on the triptych documentary research, interview and questionnaire survey. The documentary research consisted in defining the contours of the subject in order to better understand it. Then, the interviews carried out with the actors of the water sector in the Lobo basin made it possible to collect information on the perception and the mode of management of the water resources in the basin. Finally, using the simple random selection method without discount and the use of a statistical equation, a sample of 384 households spread over the entire catchment area served as the basis for our surveys. Population surveys, combined with spatially referenced data under a GIS, have made it possible to map the spatial distribution of water supply sites on the one hand, and the spatial distribution of water-related conflict types on the other. The results show that the population has a wide variety of water supply sources. Moreover, the current management mode is either liberal (or private) or participatory (or community-based) depending on the type of water resource (surface or groundwater) and on the perception of the actors with regard to water.  Thus, the different uses generate conflicts that are perceived between cultural actors (indigenous) and economic actors such as SODECI (Water Distribution Company in Côte d'Ivoire) and fishermen (non-indigenous). There are also conflicts between women, which can be summarized as disputes over water points and distrust between different communities. An integrated management of water resources in this watershed would therefore be beneficial to all stakeholders.

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Due to climate change, which has caused the scarcity of rainfall and the depletion of water resources in recent decades, Côte d'Ivoire has embarked on a planning program for the integrated management of its water resources. The present study is carried out on the Lobo watershed in Nibéhibé, located in the western part of Côte d'Ivoire (between 6°17' and 6°44' W longitude and between 6°46' and 7°41' N latitude). Indeed, the multisectoral use, the impact of climate, the demographic growth on water resources as well as the uncoordinated management lead to a crucial water shortage in the basin. The objective of this study is to propose optimization scenarios for the use of water resources for planning and sustainable management. To this end, field surveys were carried out among the state structures and the populations of the basin to acquire the socio-economic data necessary for the simulation of future water demand. The product of the specific consumptions by the levels of activities allowed to estimate the needs by sectors of activities (water supply, agriculture, and breeding) and consequently the global needs of the basin in 2021. The Water Evaluation And Planning (WEAP) model, which is a water resources management tool, was used to simulate the future water demand of the basin under different scenarios. The results show that the water demand for 2021 is 30 180 588 m3. The water demands by 2050 under the reference, low population growth rate, high population growth rate, improved standard of living and climate change scenarios are 83,700,000 m3; 57,700,000 m3; 114,100,000 m3; 107,600,000 m3 and 114,100,000 m3 respectively. As a result, the unsatisfied water demands for the same scenarios are 23,700,000 m3; 10,700,000 m3; 38,600,000 m3; 34,300,000 m3 and 38,600,000 m3 respectively. The reduction of these unsatisfied demands for the well-being of the basin populations requires the implementation of planning and integrated management systems of the basin water resources through optimization scenarios.