In Algeria, domestic water consumption data are not systematically collected, though most service connections are equipped with water meters. Water meters, however, are not maintained or periodically replaced leading to unreliable meter readings, if they are read at all. No long – or even short – term records of water consumption exist that could serve as empirical basis for the prediction of water demand in infrastructure planning and design. Several official documents propose values for water demand. These values all differ from one another, sometimes considerably. Thus, most hydraulic studies on the local level are still based on a customary value of 150 l/cap/d. This article gives an overview of the available information on domestic water demand and presents two studies that were carried out to determine domestic water consumption in the city of Tlemcen.