Quality assessment of reclaimed water for irrigation purpose and aquatic life protection in the Mekerra sub-watershed (NW Algeria)

The present study was conducted to assess the characteristics of inflow and outflow of the wastewater treatment plant of Sidi Bel Abbes (SBA-WWTP) and Moulay Slissen and Ras el Ma lagoons on the basis of a daily analyses data over a 2016-2019 period. Monitored physical and chemical parameters concerned the pH, temperature, electrical conductivity, salinity, dissolved oxygen, suspended solids, biochemical and chemical oxygen demands, nitrites, nitrates, ammonium, and phosphates. In this study, the water quality for discharged water and aquatic life was evaluated using the Canadian Council of Ministers of the Environmental Water Quality Index (CCME-WQI) method. WWTP monthly water quality of was determined using the CCME-WQI and classified as poor. As for lagoons, CCME-WQI annual values were below 40 indicating poor treated wastewater quality. These values highlight that the cleaned water is under threat and its overall quality is not close to the WHO and CCME permissible standard values. The treated wastewater of the WWTP and the two lagoons was of poor quality for irrigation use and then is not suitable for irrigation according to the Algerian standards for irrigation use.

Automated summary

The study evaluated the characteristics of inflow and outflow of the wastewater treatment plant and lagoons over a 2016-2019 period, finding poor water quality that does not meet standards for irrigation use.