Characterization of the Hydrological Balance and Assessment of the Recharge of Fractured Aquifers in the Context of Climatic Variability in Siguiri

Abstract

Climate change in the Siguiri prefecture is having a considerable impact on the water balance. With the aim of determining the hydrological balance and the quantity infiltrated into the aquifers, groundwater resources can be assessed. To carry out the study, we focused our analyses on climatic parameters (rainfall, temperature), which led to the determination of groundwater recharge in the aquifers. We found an average temperature of 26°C, with a maximum temperature of 39°C in April. The minimum temperature from December to January was 13°C. Rainfall during the dry season (November, December, January, February, March and April) was 54 mm. The average rainfall during the wet season (May, June, July, August, September, October) is 1142 mm. The imbalance in the water balance is explained by the amount of water infiltrated (41 mm or 3% of rainfall). This value, which represents a volume of 717.5 million m3 per year, is deemed sufficient to meet the needs of the population of Siguiri (695,449 inhabitants with a growth rate of 3%). Groundwater resources have been affected by rainfall deficits and variability in groundwater levels over the last forty (40) years (1980-2020) in the various localities in the study area. Precipitation water runs off (90%) more than it infiltrates (3%) into the aquifer horizons of the Siguiri prefecture, making access to drinking water difficult during the dry season for the population of Siguiri.