The second largest dam lake in Morocco, it is located in a semi-arid zone. It is deep, with very sinuous edges. When its level falls, the surface waters show a very dense vegetative carpet on the banks. Its importance is assured for irrigation, drinking water and fish farming and is of great value for waterbirds. The dam dam is located at an altitude of 285 m.

The dam reservoir contributes to recharging the groundwater table, controlling floods and regulating flows. Despite its artificial origin, this lake shows a good diversity of habitats that vary according to the water level of the reservoir. The aquatic flora is mainly composed of Chara vulgaris, Myriophyllum sp. and Potamogeton.

Winter waterbird censuses showed the presence of about fifty species whose total number exceeded the threshold of 20,000 birds three times. Some of the most remarkable wintering birds include the Marbled Teal Marmaronetta angustirostris, the Shelduck casarca Tadorna ferruginea, and the Rufous-headed Netta rufina.