Reuse of Treated Wastewater in Egypt: Challenges and Opportunities

Abstract

Limited water resources in Egypt is the main factor driving the exploration of unconventional sources that can fulfill the water demands of the increasing population. Applying treated wastewater (TWW) to agriculture is a reliable, effective method of reducing the gap between current water demand and supply. Besides saving freshwater resources, long-term reuse of TWW can enhance the physiochemical properties of light-textured soil. Pathogens and toxic chemical bioaccumulation are the main drawbacks of wastewater reuse in agriculture. Irrigation of non-edible crops with TWW is recommended under controlled management that complies with appropriate water quality standards. Monitoring the impact of reusing TWW will reduce health risks and environmental hazards. While Egypt’s total water supply for 2015 was 76.4 × 109 m3, the total refined (drinking/health use) water was 8.9 × 109 m3, which generated wastewater of around 5 × 109 m3. The primary, secondary, and tertiary treatments provided total TWW of 3.7 × 109 m3, with respective percentages of 16.8, 81.4, and 1.8%. Several organizations in Egypt are tasked with wastewater management and reuse. In addition to the Egyptian laws, legislation, and regulations enacted to protect the environment and water resources from pollution, the Egyptian Code for reusing TWW classifies wastewater into four grades (A, B, C, and D) depending on the level of treatment. There are four key challenges to reusing TWW: social (public acceptance of wastewater reuse), management (crop selection, irrigation, and soil-based practices), human health risk, and environmental threats. There are significant opportunities to maximize the benefits of TWW reuse in Egypt as less than 75% of collected wastewater is currently being treated. Finally, reusing TWW in agriculture could be the most reliable solution to overcome water scarcity and help to sustain water resources in Egypt.