Abstract
The popular chloride mass balance (CMB) method is often praised for its simplicity, especially in the groundwater recharge context. While some involved variables are indeed easy to obtain, the required atmospheric (wet/dry) chloride deposition is difficult to quantify. A literature survey, conducted for Africa and the Middle East, revealed surprising differences in the chosen approaches. This essay does not offer easy answers, but in view of many insufficiently described methodologies, it calls for more transparency in CMB studies.