الفهرس 
Chapter One : IntroductionOnly 14 pages are availabe for public view
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Abstract
Groundwater plays an essential role in the overall use and management of water resources. The demand for groundwater for municipal, agricultural, and industrial use has grown steadily during the past decades. Egypt is facing a high level of water shortage where 13.5 billion cubic meters should be contrived annually as 79.5 BCM is the annual water needs, and 66 BCM is the total available water. Groundwater is considered the second source of freshwater after the Nile River and is used for various purposes irrigation, industrial, and domestic. About 87% of the exploited groundwater is from the Nile Delta and the Nile Valley aquifers. These two aquifers are mainly replenished by the seepage from the River Nile, canals and drains network, and percolation from agricultural water.
The groundwater management of the part of the Quaternary aquifer in Assuit governorate in the Nile valley of Egypt was performed using MODFLOW groundwater modeling module. This study aimed to assess the behaviour of the groundwater aquifer and compare the groundwater heads under different scenarios of recharge and discharge. The sensitivity analysis was carried out using ModelMate, identifying hydraulic conductivity as the most sensitive parameter.
The developed groundwater model was calibrated based 35 observation wells by trial-and-error method. Groundwater heads distribution in 2020 were simulated and calculated after the steady-state model calibration for the previously mentioned parameters. The calibrated hydraulic conductivities of the upper and lower layers are 2.0 and 50 m/day. The evapotranspiration rate is 3.20 x 10-3 m/day, and the recharge from the irrigation return flow (Agricultural drainage water) is 9 x 10-4 m/day. The calibrated hydraulic conductance for the Nile River and El Fouadeya, El Faroukeya, and Ibrahimia canals range from 50 to 200 m2/day. Calibrated results showed a good agreement between simulated and observed groundwater heads where the root mean square error is 0.743 m with R2 = 0.97, which indicates consistent model performance regardless of the limitation of data availability.
Four discharge scenarios were proposed based on the current situation of the aquifer operation, where only 505 production wells are registered in the MWRI. Thus, 1.25, 1.5, 2.0, and 2.5 of the current total abstraction volumes from the aquifer were assumed to reflect the unknown numbers of the unregistered wells in the study area. Additionally, two more proposed scenarios of reducing the Nile River recharge to the aquifer were simulated for proposing 0.5m and 1.0 m reduction in the water levels of the River Nile and irrigation canals in the study area.
The model was calibrated with 28 observation wells with a good agreement with measured data. The reductions in groundwater heads are 0.17, 0.35, 0.72, 1.11 m for the four discharge scenarios, respectively, while 0.22 and 0.46 m obtained as a reduction in groundwater heads for the two proposed discharge scenarios, respectively. The recharge from the Nile and canals was reduced by 58.078, 114,800 m3/day, respectively. Sustainable management plan is recommended for long-term analysis of the Quaternary aquifer in the study area.