Abstract:Taking Lashanhe River in Jinan as the research object, aiming at its problems such as hidden water disaster risks, degraded water ecology, insufficient water resources and polluted water environment, this paper proposes a coordinated improvement scheme of "four cooperation on water". By analyzing the current situation of the river course and combining with the multi-objective needs of flood control safety, ecological restoration, resource utilization and environmental improvement, a coordinated improvement model of "water safety-water ecology-water resources-water environment" is constructed by comprehensively using technical means such as desilting and dredging, rainwater and sewage diversion, ecological water supplement and landscape construction. After the implementation of the project, the flood control capacity of the river course has been upgraded to the standard of once in a hundred years, and the ecological base flow has increased by 50,000 m3/d. The research results show that the "four cooperation on water" model effectively realizes the coordinated optimization of multi-dimensional improvement objectives, providing a scientific reference for the comprehensive improvement of urban river courses.