The artificial wetland water purification project in a certain watershed in Rizhao, Shandong Province covers an area of 41 hectares, with a designed inflow of 30000 tons/day. The inflow water quality is Grade A of the "Pollutant Discharge Standards for Urban Sewage Treatment Plants" (GB 18918-2002), and the river treatment+subsurface flow wetland+surface flow wetland treatment mode is used to achieve Class III water in the "Surface Water Environmental Quality Standards" (GB3838-2002). The construction of wetlands is of great significance for improving the ecological environment along rivers and enhancing the quality of urban environment.