الخلاصة:
The Rhumel Upstream in the Constantinois, is drained by the high valley of the Rhumel, over an area of 1130 km2. It is constituted by three main hydrogeological systems : the superficial Mio-Plio-Quaternary aquifer, the Eocene aquifer and the Cretaceous one. These two latter constitute a multilayered karstic aquifer, which reveal a ground water outlets, partially thermal (spring of Hammam Grouz). Piezometric stydy deals with data of two campaign measurements. The potentiometric surface of the superficial aquifer varies between 800 m at the center of the plain and 1000 m near the massifs, with a main drainage towards Rhumel Wadi. The various chemical facies show the dominance of the chlorides, revealing a pollution. The behavior of the Hammam Grouz dam, controlling the supply of the Haut Rhumel is studied by the data of the regularizing water balance of the 1987/08 period. It has shown the exceptional character of the 2002/03 year, leading to the problems of leakages towards the dam downstream and to an appearance of an important pits (vortex), this problem of water lightness is the relate to the functioning of the complex karstic system of the region.