Strategies and methods for improving the quality and efficiency of the urban drainage system

China has entered the crucial period to eliminate the urban black and odorous water bodies by 2020.To win the battle of pollution prevention and control,the Party Central Committee and the State Council have proposed a three-year action plan to improve the quality and efficiency of the urban drainage system,providing the guidelines for local governments to take effective and practical measures.The three—year action plan focuses on the problems solving in the sewerage system based on the complete investigation,including the sewage direct discharge,mixed flow of clean and dirty water,full-section pipe-flow of drainage pipes in the dry season,low pollutants concentration of the influent in wastewater treatment plant and accumulated sludge in the pipelines.This paper summarized the strategies and methods in avoiding the sewage into the river,preventing the clean water into sewers and reducing overflow pollutants,thereby enhancing and consolidating the remediation effect of black and odorous water bodies.