Impact of Lake Nasser on the groundwater of the Nubia sandstone aquifer system in Tushka area, South Western Desert, Egypt

Lake Nasser recharges the aquifers in study area by large amount of water increasing the groundwater level upward in the study area and decreasing groundwater salinity. The main result of the current study shows that the seepage water from Lake Nasser attains 24 × 106 m3/year. Lake Nasser is located within the Abu Simbil and Sabaya Formations, which are characterized by a high hydraulic permeability and affected by E–W fault system. The groundwater is exploited from Abu Simbil and Sabaya sandstone aquifers. These aquifers exist under confined to unconfined conditions. The groundwater flows towards the north and northwest direction from Lake Nasser.The groundwater salinity increases towards the northwest direction coinciding with groundwater flow. This water salinity is probably decreased with time. This is mainly referred to the seepage of fresh water from Lake Nasser. The same hypothetical salts are detected in the water of Lake Nasser and the aquifers indicating that the groundwater in the study area is directly recharged from Lake Nasser.