الفهرس 
CHAPTER 1 INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
In this research study, multi-criteria decision analysis (MCDA) was used to delineate potential groundwater recharge areas for MAR implementation projects in Western Delta of Egypt using reclaimed wastewater. By employing geographical Information systems (GIS), and Pairwise Comparison Matrix (PCM), a modified approach was utilized for the development of a suitability map by capturing the interlinkages between a specified MAR technique (Spreading methods) and MAR suitability mapping processes. The developed approach was created with a range of constraining and factoral considerations, including hydrological, environmental, hydrogeological, and socioeconomic criteria.
The influencing criteria under this research are integrated using INOWAS’s modeling platform, a Linux open-source empirical, analytical, and numerical web-based modeling tool created by INOWAS in 2019 to aid in the development, planning, management, and optimization of MAR applications. Based on the findings, MAR potential recharge zones indicated four main suitability classes. Areas associated with each suitability class were calculated. It was noticed that there were no unsuitable areas for recharge, while the percentage of low suitability areas was around 12% of the total areas. Areas with moderate suitability were around 65%, and suitable and highly suitable areas for recharge were around 23%. The presence of high-suitability areas was mainly delineated in the northeast part, particularly around the left side of the Nile River valley. Areas of low suitability were located around the west-north side where the hydrological criterion seems to hinder the implementation due to the low productivity of the hydrogeologic layer.
Additionally, a spatially explicit sensitivity analysis is performed using spatial visualization to examine the effect of various weighted criteria on the final outputs and identifies criteria that are especially sensitive to weight changes. The obtained maps reveal that the most sensitive criteria/influencing parameters are the type of hydraulic conditions (HC) followed by the distance from the wastewater treatment plants (DWTPs) which resulted in the presence of low suitable areas of recharge, followed by the aquifer type (AT). The results of the sensitivity analysis indicate that the applied MCDA framework for the suitability mapping in West Delta produced robust results in terms of the most suitable sites for MAR. The obtained results also indicate the possibility of the use of the suggested framework for arid environments with comparable data availability. The results also confirmed that the produced maps can be utilized as a decision-making tool to support actual planning and implementation of spreading methods in the West Delta. With the implementation of MAR, such maps can be used in a participatory manner to identify unforeseen social hotspots and obtain public approval prior to implementation. Based on the findings, a more environmentally friendly and beneficial use of treated wastewater is proposed to close the current supply-demand gap in West Delta and allow for more informed science-based decisions to be made to advance water and food security in the Delta region. Additionally, a possible reduction in over-exploitation of current groundwater resources can be obtained through the expand utilization of non-conventional water resources.