A demonstration of wastewater treatment for reuse applications in fish production and irrigation in Suez, Egypt

Abstract

About 400 m3/d of raw sewage from the City of Suez were diverted and treated by two parallel pond systems. The first treatment system was conventional Waste Stabilization Ponds which included anaerobic, facultative, and maturation compartments for a total residence time of 21 days. The second system included a series of four plankton ponds with a total residence time in the order of 26 days. The effluent from these inexpensive, but yet effective treatment technologies, was found to conform to the World Health Organization (WHO) standards for unrestricted agricultural and aquacultural applications. The treated waste effluent was successfully used to grow two types of local fish, i.e.Oreochromis niloticus and Mugil sehli. Fish production, without supplemental feeding or pond aeration, reached 5-7 metric tons/hectare/year. Furthermore, the fish were found to be free from human parasites and safe for human consumption. The nutrient rich effluent from the fish pond was further used to grow trees and cultivate certain types of crops, i.e. barley, maize, beets and ornamental plants. This study clearly demonstrates the effectiveness and benefits of waste stabilization ponds systems for low cost treatment of domestic waste and the combined reuse in aquaculture and agriculture applications. In addition, the unique treatment/reuse facilities constructed at Suez will continue to function as an experimental station and serve scientists and engineers to study and to plan applications in Egypt and the region.