Case analysis on the treatment of black and odorous water body in Licun River, Qingdao City

The Licun River basin was the largest river system in the downtown area of Qingdao and the largest river crossing the city. The weak infrastructure, prominent urban non-point source pollution, inadequate long-term mechanism, low ecological stability of the river channel and poor environmental awareness of residents along the river had caused black and odorous problem in the Licun River all the year round. Since 2016, the Licun River had been comprehensively rehabilitated from five aspects, i.e. source control and pollution interception, endogenous pollution control, ecological restoration, maintaining the living water quality, and long-term management mechanism. The main measures included upgrading of sewage treatment plants, diversion of rainwater and sewage pipelines, garbage removal and transportation, silt dredging, ecological restoration and water replenishment, and establishment of river management mechanism, etc. In the process of ecological water replenishment and water regulation and storage of the Licun River, laying of reclaimed water pipeline without excavation at the bottom of the Licun River was innovatively carried out, by incorporating the trenchless directional drilling crossing technology of the pipeline. After the regulation of Licun River basin, the black and odorous water body was eliminated, and the Licun River had been built into an ecological landscape corridor integrating the functions of leisure, fitness and ecological adjustment, with perennial water, clean water and green banks.