الفهرس 
Chapter 1 : IntroductionOnly 14 pages are availabe for public view
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Abstract
It is obvious from the model results that surface water system and groundwater system cannot be considered as separated systems. In fact, they are interconnected systems. Any change in one of them will affect the other. During decreasing surface water levels, the recharge from surface water to groundwater is decreased and the aquifer storage is decreased while, during increasing groundwater extraction, the recharge from surface water to groundwater is increased to compensate the decreasing in aquifer storage. Groundwater flow is toward the River Nile and Zone Budget results indicate that the River Nile is in direct contact with the Quaternary aquifer system and acts as a drain along most of its length in the study area, but El Ibrahimiya and Bahr Yusef act as source of recharge to the aquifer. Hydraulic conductivity of the colmation layer of the water streams is mainly controlling the infiltration from surface water to groundwater as well as the hydraulic gradient. from first scenario, the predicted decrease of surface water levels due to constructing the (GERD) is unknown. But, if surface water levels decreased by 0.5, 1, or 1.5 m that will decrease groundwater level in the Quaternary aquifer and decrease its storage, especially if the decreasing of surface water levels was more than 1.5 m due to the highly decrease in recharge from SW to GW.
from second scenario, successive increase in groundwater extraction cause a decrease in groundwater storage and groundwater level in the Quaternary aquifer. However, the decrease in aquifer storage is lower than that of the first scenario. This is attributed to that the increase of recharge from SW to GW is due to the increase of groundwater extraction. Especially if the groundwater extraction is increased by more than 3×106 m3/day. That is clearly present in the area west of Bahr Yusef where, cone of depressions are getting bigger with the increase of groundwater extraction and that is because of the increasing number of pumping wells as well as the small thickness of the Quaternary aquifer in that area.
The third scenario showed that the construction of the (GERD) will not only cause the storage and groundwater level in the Quaternary aquifer to decrease, but will district the possibility of increasing groundwater extraction in the study area and development in all fields especially, irrigation. In bank infiltration process, surface water is drawn off by extraction wells located at some distance of the water body for water purification. Due to groundwater flow is toward the River Nile in the study area, bank infiltration cannot be carried on from the River Nile, but it can be done from El Ibrahimiya and Bahr Yusef canals where the flow is from SW to GW.