Construction guidelines for Chongming eco-island points out the goals of ecological protection and construction for Chongming eco-island in 2020 and puts forward specific requirements for the water-related evaluation indexes.Based on the background of guidelines,this paper investigated the present states of the water qualified rate in key watercourses,the attainment rate of drinking water quality and the centralized disposal rate of urban sewage.Then it analyzed the gaps between present states and the requi...