The spatio-temporal dynamic of land use in the Bonoumin and Gourou watersheds, over the last three decades (1990 to 2020), were analysed using Landsat images (1990, 2005 and 2020), remote sensing and a geographic information system (GIS). The main objective of this study was to analyse the impact of changes in land use in these two watersheds on stormwater runoff, which is responsible for flooding in the study area. The methodology adopted consisted of first downloading the Landsat images, which were then pre-processed, before undergoing several processes, leading to the classification and analysis of land cover dynamic. Maximum likelihood supervised classification was applied. Thus, the results of this classification showed that over the last three (03) decades, the impermeabilised surfaces in the two watersheds, represented by the medium and highly densified urban areas, have increased significantly, unlike the vegetated surfaces, which have decreased significantly. The increase in impermeable surfaces reduces the capacity for water to infiltrate the soil and increases the amount of runoff. The results also showed that in recent years, the upper reaches of the Bonoumin watershed have come under considerable anthropogenic pressure. This means that in a few years time, there will be a sharp increase in the amount of runoff water in the lowlying areas of this basin, and therefore an increase in the risk of flooding.

This study carried out on the Marahoué (Bandama) watershed at the Bouaflé hydrometric station (Côte d'Ivoire) aims to characterize climate variability and its impact on the variations and availability of water resources in the watershed of the Marahoué (Bandama) in Ivory Coast. This characterization was based on the use of rainfall, thermometric and hydrometric (flow) data collected over the period 1961-2017. Thus, several methods were used (standard index of normalization, Lang method and Maillet's law). There is a decrease in precipitation and flow, however the temperature is rising. A low storage capacity of soil reservoirs in the Marahoué watershed (Bandama) has been demonstrated. Thus, low groundwater reserves were evaluated characterized by a low average drying off coefficient of 3,4.10-2 j-1, a short drying period of nearly a month and a low volume of water mobilized by the aquifers of 0.92 Km3.

The aim of this study is to analyze the dynamics of seasonal climatic regimes in a context of changing climate with a view to redefining homogeneous climatic zoning in Ivory Coast. The methodology is based on the combination of climatic indices designed from rainfall and temperature (Gaussen index and De Martonne index). The results obtained made it possible to identify six (6) homogeneous climatic zones in Ivory Coast. A diachronic analysis from two thirty-year periods (1941-1970 and 1971-2000) showed that the climate changes observed in West Africa in general and in Ivory Coast in particular, had the consequences of modifying the seasonal climatic regimes conditions in general throughout the territory. However, the Ivorian coast was less affected by the phenomenon. The results obtained can serve as a basis for forecasting drought in Ivory Coast.

The objective of this study is to model the maximum monthly average annual flows (QMXA) in order to define a flood warning system in the catchment area of the Marahoué (Bandama) (Bouaflé hydrometric station). The methodology used is based on frequency analysis of QMXA (1961-2017) and also on the determination of flood thresholds to give early warnings. Standard laws were selected to conduct frequency analysis. It is clear from this study that the QMXA of the Marahoué have been better adjusted by the Gamma law, followed by the Weibull law finally comes the Log-normal law.The different flood thresholds were therefore assessed on the basis of the Gamma Law. It is the dalerte threshold (802 m3/s), the tolerance threshold (721.8 m3/s) and the crisis threshold (882.2 m3/s). These different thresholds constitute a dalerte system of floods from the Maraboué to Bouaflé.

This study aims to assess the evolution of water balance parameters watershed Comoe in a context of climate change. Using the GR2M hydrological model, climate data from the climate model RegCM3 under the A2 emission scenario were simulated to get infiltration, runoff and evaporation and plant transpiration for the periods 1991-2000, 2031-2040 and 2091-2100. Similarly, monthly hydrological and climatic data were used to calibrate the parameters of GR2M hydrological model over the period 1961-1990. The calibration of the hydrological model gave Nash values between 57% to 72%. At validation, Nash criterion varies from 51% to 75%. The results of projection, revealed a decrease in runoff of 18.8% to 34% in 2031-2040 and 40% to 73% in 2091-2100 horizon in different localities. Refills of sheets that are through infiltration could decrease by 7% to 13% in 2031-2040 horizon and 49.3% to 70% in 2091-2100. The decrease in these two consecutive hydrological parameters is, firstly, to falling precipitation of 7.17% and, secondly, an increase in the evaporation and plant transpiration via the temperature increase of 3.6

The workshop of the interdepartmental committee responsible for managing household waste in Abidjan (Ivory Coast) in 2007 showed that the landfill site should be chosen out of the coastal sedimentary basin to protect the groundwater of the Continental Terminal aquifer against pollution. Indeed, this aquifer provides the potable water to Abidjan populations and also assures uniformity of the price of water by the water company of the Ivory Coast. But, given the groundwater flow and the possibility of transfer of fluid between the discontinuous and continuous aquifers, is it possible that an activity taking place outside the coastal sedimentary basin of C

In Ivory Coast, the phenomenon of decline of water drilling is found in rural and urban areas in the crystalline and crystallophyllian basement. The sub-prefecture of the department Angoda Toumodi does not rest (55%). Although several factors such as the condition of equipment, operating conditions, power conditions, the lithological conditions, problems of monitoring of hydraulic and quality parameters, etc., may partly explain this phenomenon, a fundamental question needs to be asked: drilling decline is it not related to a bad implementation of drilling? Thus, this study aims to analyze the productivity of water wells in operation, implemented by the method geomorphic from geophysical measurements. The study area is sub-prefecture of Angoda which lies between longitudes 5

The study area is the N'zo-Sassandra watershed (Ivory Coast) located between longitudes 7

This study aims to evaluate the hydraulic properties of crystalline and crystallophyllian bedrock aquifers of N'zi-Como