Evaluation of groundwater recharge was conducted in the area around Kanye, southeast Botswana using the chloride mass balance (CMB) technique. Thirty-seven (37) years of rainfall data were examined to define the seasonal distribution and the average rainfall in the study area. The rainfall pattern through the twelve months of each year was further analysed using rainfall coefficient techniques. Thirteen (13) samples of groundwater from different wellfields collected during the rainy and dry season were analysed for chloride and bromide concentrations. Additionally, chloride levels in rainfall for wet and dry seasons were obtained from previous groundwater recharge evaluation study in the region. Two rainy seasons and one dry season recognised in Kanye area yield an average annual rainfall of 466.17 mm. Fifty-seven per cent of this amount occurs in the first rainy season (January to April), thirty-seven per cent occurs in the second rainy season (October to December), and six per cent occurs in the dry season (May to September). The CMB method suggests that the groundwater recharge ranges from 4.79 mm/yr to 26.57 mm/yr. The recharge in the first rainy season is estimated to be 5.70 %, whereas the recharge in the second rainy season and dry season are 4.09 % and 1.03 % of the average rainfall. The results show that large amounts of water are lost in different forms. Harvesting of this lost water could enhance the groundwater resource of the Kanye area.

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