Groundwater is the world's largest source of fresh water, but its safe and sustainable exploitation remains a challenge. Egypt's Nile Valley aquifer is the most important renewable aquifer, accounting for approximately 85% of total groundwater use in Egypt. Egypt's long-term development and socioeconomic growth in the Nile Valley depends on this groundwater. Concerns about groundwater assessment, quality, management, and sustainability frame the current status of Nile Valley groundwater supplies. Proper knowledge of the current state of the groundwater quantity and quality in the Nile Valley...