Application of water quality indices for assessment of influent and effluent wastewater from wastewater treatment plant of Oran City, Algeria
Madani Bessedik, Chérifa Abdelbaki, Nadia Badr, Sidi Mohamed Tiar, Abdesselam Megnounif
Abstract
ABSTRACT Water quality assessment is a significant criterion in matching water demand and supply. In this research, two water quality indices (WQI) methods were applied to evaluate the influent and effluent water quality of the Oran municipal wastewater using nine parameters (temperature, pH, total suspended solids, biochemical oxygen demand, chemical oxygen demand, electrical conductivity, nitrate–nitrogen, phosphate and the daily flow) and two calculated quotients for data recorded in the years from 2011 to 2019. The results pointed that the quality of the treated wastewater was declined from good in the years 2011 and 2012 to poor between 2016 and 2019. For those last 4 y, water quality deteriorated to the point that most WQI indicated noticeable deviation from desirable levels, due to the impact of several anthropogenic activities with a higher level of pollution than its treatment capacity. This in turn makes the effluent water unusable for irrigation. Application of the WQI is suggested to be a very helpful tool that enables the public and decision-makers to understand and manipulate the water quality of any aquatic system with great flexibility in the variable’s selection.