Enhancement of the study of water leaks in the Algerian dam of Foum El Gherza

Foum El Gherza dam is studied herein due to its considerable loss of water resources. It is progressively threatened by water leaks with an interannual leak flow estimated at 5 hm 3 . In this study, we undertake this problem through hydrochemical methods, tracer techniques, and physicochemical characterization including pH, conductivity, and temperature variation in order to detect water leakage combining conventional, tracing, and isotope techniques and forecast the possible treatments. The obtained results by a physicochemical study showed two types of flows. The first one is vertical downward, depicted by practically constant temperature and conductivity values, whereas the second is oblique and almost horizontal resulting from the reservoir. This one was revealed by low conductivity and homogeneous of temperature values. This reflects the degraded state of the geological layers at the level of both banks of the dam. The temperature and the conductivity evolve with depth from one point to another according to the geothermal gradient and the geologic layers of the site. This variation further confirms the degraded state of these layers. Thanks to the obtained results, a leak flow variation was established according to the water level in the dam.