The supply of quality drinking water in the religious city of TOUBA remains a major challenge for the state and local authorities. The aim of this study is to assess the hydrochemical quality of the Maastrichtian aquifer located in the TOUBA hydrogeological basin. Specifically, the study focuses on fluoride and dry residue concentrations. We worked with hydrogeological data received from the Water Resources Management and Planning Department from 54 boreholes that tap the Maastrichtian in Touba and the surrounding area. The results show that in the area, the quantity of dry residues and the concentration of fluoride are high, even exceeding the threshold set by the WHO in some boreholes. Fifty-two (52) out of fifty-four (54) of the boreholes studied, i.e. 96.3%, have a dry residue concentration above the WHO limit value (1000 mg/L), and only ten (10) of the 54 boreholes studied, i.e. 18.5%, have a concentration below 1.5 mg/L (WHO standard). Consumption of this water without prior treatment may constitute a public health problem in TOUBA.

Issues related to climate change are now at the heart of high-level scientific debates in the hope of identifying vulnerable areas. Among Senegal’s agroecological zones is the peanut basin the main area for growing peanuts and dry cereals, which is exposed to climate variability. Understanding the spatial and temporal variability of temperatures and precipitations, as well as characterizing their trends, is crucial to grasping the significance of climate change and its impacts on agroecological areas. To understand the diachronic evolution of temperatures and precipitation in the Peanut Basin, the research methodology was structured around the standardized precipitation index, the spatialization of maximum temperatures, the identification of thermal anomalies by applying the Lamb index, the detection of trends using the Mann Kendall test and the Sen slope following an established time step from 1981 to 2024. This reveals that in the Peanut Basin, on an annual scale, the distribution of maximum temperatures fluctuates between 35°C and 45 °C. However, the variation in average maximum (Tmax) and minimum (Tmin) temperatures indicates a more significant increase in minimum temperatures associated with a positive Sen slope at the Fatick, Kaolack, and Koungheul stations, confirming the hypothesis of the warming hypothesis in the central-south where the resumption of wet stages follows essentially dry occurrences with average annual rainfall oscillating between 509.62 mm (Thiès) and 715.27 mm (Koungheul).