The invention relates to a method and installation for treating water for human consumption, for an industrial process, for agricultural purposes or for other purposes. The method used to remineralize raw water comprises a stage in which carbon dioxide and at least one inorganic base are injected. According to the invention, the method comprises the following stages: the flow Q of raw water is separated into a flow Q1 and a flow Q2; only flow Q1 is remineralized by injecting carbon dioxide and at least one inorganic base, said remineralization being carried out in at least one remineralization basin; remineralized flow Q1 is mixed with untreated flow Q2.