Suitability of Treated Wastewater Produced in Sudan for Irrigation Plants

Abstract

The aim of this study was to characterize the quality of treated wastewater of Soba treatment plant, in Khartoum state, in term of its potential to be used in irrigation for different plant products, as well as to study the temporal variations of its physicochemical and biological parameters. Sampling of the treated wastewater was performed during Dec. 2014 and November 2015. The parameters indicating the suitability of such wastewater for irrigation were estimated, these include pH, Total Suspended Solids (TSS), Electrical Conductivity (EC), Total Dissolved Solids (TDS), Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), Sulphate, Ammonia, Chloride as well as total count, coli from bacteria and parasites. Results showed that, significant variation in values of pH, EC. Chloride, sulphate, BOD, COD was observed throughout the months of year. In spite of variability throughout the year, the values of pH, EC, TDS chlorides and sulphate, in term of their suitability for use in irrigation, fall within the limits set by FAO for irrigation water. Concentration of total coliform and nematodes in treated wastewater, were more than the concentration limit set by WHO, for restricted irrigation, and less than the limit for unrestricted irrigation. The reuse of the treated wastewater in irrigation of non food crops could be carried out without restriction, however, regarding the use of restricted irrigation, it would be necessary to upgrade treatment processes for further reduction in some parameters, providing that, regular testing should be done regularly.