Using QUAL2K Model and river pollution index for water quality management in Mahmoudia canal, Egypt

Abstract

The Mahmoudia Canal is the main source of municipal and industrial water supply for Alexandria (the second largest city in Egypt) and many other towns and villages. In recent years, considerable water quality degradation has been observed in the Mahmoudia Canal. This problem has attracted increasing attention from both the public and the Egyptian government. As a result, this study aims at assessing the current seasonal variations in water quality in the Mahmoudia Canal and simulating various water quality management scenarios for the canal. The present research involves the application of the water quality model, QUAL2K, to predict water quality along the Mahmoudia Canal on a seasonal basis for the considered scenarios. Based on the QUAL2K simulations, the River Pollution Index (RPI) was used to appraise the conditions of water pollution at the intakes of the twelve water treatment plants (WTPs) located along Mahmoudia Canal.

The results showed that the QUAL2K model is successfully applied to simulate the water quantity and quality parameters of the Mahmoudia Canal in different seasons. For the current status of the canal, it was found that the highest pollution level occurred in autumn in which effluent water quality at all WTPs along the Mahmoudia Canal was classified as moderately polluted. In the other seasons, effluent water quality was categorized as moderately polluted at most WTPs in the Beheira governorate and negligibly polluted at all WTPs in the Alexandria governorate. Moreover, it was concluded that controlling the Rahawy drain discharge or treating its pollution loads before mixing with the Rosetta Branch may solve water quality problems of the Mahmoudia Canal and allow re-running of the Edko re-use pump station in summer, winter, and spring. However in autumn, additional measures will be required to mitigate pollution levels in the canal.