Assessment of Urban Wastewater Reuse for Irrigation -- Environmental Feasibility and Sustainable Development -- A Case Study in El Jadida.

Morocco, like other arid and semi-arid countries, faces a growing water shortage, necessitating the exploration of alternative solutions. This study investigates the potential use of untreated urban wastewater for irrigation and environmental impact mitigation, focusing on El Jadida as a case study. Throughout the year 2023, from January to December, a comprehensive characterization of physico-chemical, heavy metal, and biological parameters of this unconventional water source was conducted to account for seasonal variations, particularly between rainy and sunny periods. Samples were collected at the inlet of the El Jadida wastewater pre-treatment plant (WWTP) to assess the city's net pollution levels. Results indicate high values for chemical oxygen demand (COD = 741 mg/L), biological oxygen demand (BOD₅ = 344 mg/L), organic load (BOD₅/COD ratio = 2.2), and biodegradability, suggesting a strong need for biological treatment. Despite compliance with discharge standards, concentrations of heavy metals such as mercury (Hg), cadmium (Cd), aluminum (Al), manganese (Mn), and fluoride ions (F^-) exceed Moroccan irrigation water quality thresholds by 90%, 66.7%, 21.8%, 33.3%, and 86.1%, respectively. Therefore, advanced chemical treatment is highly recommended to mitigate environmental impact and ensure safe reuse for irrigation. The novelty of this study lies in evaluating the suitability of El Jadida's wastewater for irrigation and environmental impact mitigation, underscoring the critical need for effective treatment solutions to enhance water sustainability in Morocco. Future research will focus on optimizing water treatment processes. [ABSTRACT FROM AUTHOR]