Physicochemical Characterization and Evaluation of the Organic Pollution of Domestic and Industrial Wastewater in the City of Fez

Abstract

Environmental concern implies a degree of basic dynamism aimed at safeguarding ecosystems against any type of pollution and better management of the environment. Wastewater is mainly composed of water and other materials that represent only a small part of wastewater, but can be present in sufficient quantities to endanger public health and the environment, so before discharging wastewater into the natural environment, it is necessary to define its parameters to have information on the composition and qualitative and quantitative characteristics of wastewater and their impacts on the receiving environment. The goal of the conducted work was to determine the degree of wastewater pollution in Fez based on the results of physicochemical analysis of samples collected from various stations in 2021. The temperature varies between 24.6°C and 29.9°C in wet periods and between 26.5°C and 38.3°C in dry periods, the pH is alkaline to neutral with high turbidity levels, especially in wet periods, for dissolved oxygen, the wastewater of the city of Fez is under saturated in oxygen, which accentuates anaerobic fermentation and the release of bad odors, and the average values of the BOD5are higher than 100 mg O2/l considered. These wastewaters are rated as being of very poor quality. COD values are greater than 500 mg of O2/l, which is considered the limit value for direct rejections. Nitrate concentrations are highest in S1, with a value of 12.83 mg/l in the dry period. The recorded contents of orthophosphates and total phosphorus do not vary significantly. The obtained values are higher than the WHO recommended wastewater discharge standards. At the conclusion of this research, it was discovered that the wastewater in the city of Fez is of poor to very poor quality.