الفهرس 
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Abstract
Groundwater resources planning, as a part of the water resources management, is strongly interrelated to the other planning areas (Agricultural, Industrial, Urbanization development). Accordingly, the multiplicity of objectives formulated from these perspectives has strong implications for the planning and development of groundwater.
Eastern Nile delta region is considered one of the highest development areas in Egypt for more than the last forty decades. South Eastern Nile delta fringes especially will be selected to be the area of interest. Special attention will be given to the existing large reclamation lands (surface water, and/or groundwater reclamation lands) in both low and high rolling desert lands. where the low ones are located south and adjacent to the Ismailia canal. Under the expected stress of extensive shortage in surface water of the Nile water system, rapid population, and urbanization, accordingly, there is an importance of the global water resources planning such as groundwater can be used conjunctively with surface water and unconventional resources (treated drainage and waste water).
The main issue addressed in this research is to manage the Nile Delta aquifer operation during a water crisis for the sustainability of the water resources and existing large reclamation projects (mainly based on surface water). Therefore, this work aimed to 1) Set up groundwater development strategies during the water crisis which is accompanied by reduction of inflow of the river and its branches in the flood plain of Eastern Nile Delta. 2) Obtain a recommended strategy for groundwater development in the area of interest for the safe operation of the aquifer, maintaining the sustainability of water resources.
In the current research, integration of GIS and remote sensing (RS&GIS) was used in the South Eastern Nile delta region to monitor the change in land use/cover and to assess the change in the agricultural lands in the desert areas. Three satellite images for years 1992, 2002, 2015 were used to produce the land use/cover maps using the maximum likelihood method by selecting four classes for land cover (Agricultural, water, desert, and urban). The accurate assessment of the land use classification was evaluated and three maps for change detection analysis were produced between the years (1992-2002), (2002-2015), and (1992-2015). The final assessment concluded that the area of agricultural lands of the existing reclamation projects started before 1992 were increased by 17527.6 (feddan) from the year 1992 to 2015 while the reclamation lands that planned by the Land master plan from (1992 to 2017) were to 115436 feddan for the same period of years.
This research depended on the numerical flow model as a helpful and strong tool to test several scenarios under three strategies to assess the impacts of such strategies on the groundwater system during the expected shortage of surface water. A three-dimension groundwater model (visual MODFLOW.pro) was applied considering the prevailing condition of hydrogeological conditions of the aquifer characteristics, the Hydraulic properties of irrigation and drainage system & expected changes under expected water shortage, and the change of land use.
The model was simulated and calibrated for the prevailing hydrogeological conditions throughout the period (1992-2015). where the calibration 1992 was applied in a steady state condition, while the period 1992 to 2015 was applied in an unsteady state condition. The final outputs of calibration 2015 were used as a reference for the groundwater development strategies. Three groundwater development strategies were proposed, based on the relation between the additional pumping thickness from medium to high potential aquifer zones under flood plain located in the north part of the model area versus the reduction surplus subsurface drainage in the large reclamation lands use surface water,1) long term strategy (steady state); 2) short term (inter-annual); and 3) intra- annual strategy.
I-The long term pumping strategy (steady state) includes three scenarios with simulating additional pumping thickness against surplus subsurface drainage distributed in some areas in the flood plain (medium to high potential aquifer) by 10% (471 Mm3/year), 15% (706 Mm3/year), and 20% (941 Mm3/year). II-The short term pumping strategy (inter-annual) comprises three scenarios with applying different pumping thicknesses as the same as in the long term but distributed seasonally by 60% in the summer season (6 months from April up to September) and 40% in winter (6 months from October up to January).
This strategy was carried out in an unsteady state condition. III-The intra-annual operation strategy of four scenarios was tested for their effect on the groundwater system. Based on the combination of the three schemes of the pumping (471 Mm3/year, 706 Mm3/year, 941 Mm3/year) together in different periods in the first three scenarios against drainage surplus with the reduction value of scenarios (10%, 15%, 20%). While the fourth scenario is based on the long-term pumping under the scenario (10%). This strategy was carried out in the unsteady-state condition. All strategies are mainly conjunctive use.
In general, there is a decrease in the rising of the water table at the large reclamation areas (Mullak and Manayf), with the increase of the reduction in subsurface drainage. The maximum decrease in the rising of the water table was obtained at both the third scenario of the inter-annual strategy and the first scenario of the intra-annual strategy, amounting to -0.66 m and -0.67 m respectively. Also, at different seasonal (inter and intera) scenarios, there is a reduction in the non-beneficial losses through controlling the water table at surface water large reclamation areas (located at southern of Ismailia Canal) to minimize waterlogging.
In general, in all different scenarios, the maximum drawdown often occurred at the north of Ismailia Canal where the pumping zone was located. Although there is a limitation in the fresh water thickness, it is still within the permissible limit. the change in the groundwater levels and the relevant change of storage is mostly recovered during the winter season (low pumping period). But, in general, with time, there is a decrease in the change in the groundwater storage per year and accumulative value.
This study recommended the seasonal pumping operation to be the suitable solution in the Eastern Nile Delta region, where the max capacity of the additional pumping thickness against the drainage surplus should not exceed that of the net recharge, with operating 7 or 8 years and then followed to release through several years of zero pumping (safe operation) for the aquifer storage to be recovered but in quantities compatible with the change in the storage in the future under the impact of the expected scenarios.