Benin’s artesian groundwater resources are still underutilized and therefore do not yet contribute fully to the country’s socioeconomic development. This is the case with the Hêtin-Sota thermal spring, which appeared following drilling in 1956. In order to assess the Hêtin spring with a view to developing it, it is necessary to know the values of certain fluid parameters (pressure and temperature) that are not available in the literature or in the archives of Benin’s Directorate General of Water (DGEau). These include the temperature and static pressure values in the reservoir at this location, as well as the pressure value at the head of its artesian thermal well, given that the temperature value at the ground surface (Tground=53℃) is known. This work provides an in-depth study of the different stages through which the geothermal fluid circulates and the interactions between them. The code developed during this study solves the simplified Navier-Stokes equations, the heat equation, and the momentum equation using the Matlab language. This code confirms the temperature (Tres=66.76℃) and static pressure (pres=58.38 bar) values in the reservoir at this location, as well as the head pressure (phead=15.62 bar) value of the thermal artesian well. Validation of this code shows that in the Hetin-Sôta artesian and thermal well; the simulations are in good agreement with the drilling pressure logs and geothermal fields. The temperature above ground, i.e., at the top of the Hêtin artesian and thermal well, is 53°C, which is between 30°C and 90°C, and the depth of the well-being 417 m, between 400 and 2000 m, the geothermal energy from this well can be used to develop agricultural land in the Hêtin area, which is part of the Ouémé Valley in Benin, ranked as the second richest valley in the world after the Nile in Egypt.

In developing countries, cities urbanization usually lack planning processes and quantitative consideration of impacts on aquatic receptors. This work evaluates by defining a nutrient quality index, the link of urban increasing with surface water resources quality. Four basins of different levels of urbanization in the Parakou city in West Africa served as a framework for the study. For headwater basins, which are essentially urban extension area (Ganré in the North and Dama in the South), the results indicate that the surface waters are of a very close and fairly good quality with a minimal index of 0.95 in the rainy season and 0.88 in the dry season. The basins of the old urban core, Kokouro and the wonka are at 0.84 in the rainy season and 0.89 in the dry season at the minimum. The quality index deviations obtained are not more than ± 0.08. Good consistency is obtained between our quality index with the organic pollution index of Leclercque and 72.49% variance of the dependency link between urbanization and surface water pollution can be explained by the quality indices and subdivision indices. These results indicate the need for better management of urban sprawl for the preservation of the quality of surface water resources.