Investigation and Analysis on Rural Domestic Sewage Discharge in Key Watersheds

Abstract

Abstract In order to grasp the latest changes in the quality and quantity of domestic sewage in the Taihu Lake Basin and Chaohu Lake Basin, and to scientifically guide the construction of rural sewage treatment demonstration projects, two typical villages were selected from Taihu Lake Basin and Chaohu Lake Basin respectively for fieldwork continuous monitoring of sewage water quality and quantity. The results show that the typical rural per capita daily drainage in the plain area of the Taihu Lake Basin in summer is 89.4 L·cap−1·d−1, which is significantly higher than that in the typical rural area of the Chaohu Lake Basin (56.5 L·cap−1·d−1). The amount of sewage hourly discharge fluctuated distinctly, and the coefficient of variation of sewage discharge in the two villages ranged from 2.4 to 6.1, showing obvious characteristics of “morning and evening peaks” or “morning, noon and evening peaks”. In addition, the rural sewage water quality in the two places shows the same pattern, and the pollutant concentration of sewage from different sources is significantly different. It was found that the toilet-flush sewage in Wangjiatang village provided 84.42% of TN and 92.94% of NH4 +-N in the total domestic sewage, while toilet-flush sewage in Qianying village provided 74.31% of TN and 84.56% of NH4 +-N in the total domestic. Therefore, when constructing a sewage treatment demonstration project, the ideological principles of sewage classification and treatment from the source should be considered.