Abstract:The pollution caused by combined sewer overflow is an environmental issue of global concern at present, which seriously restricts the continuous improvement of urban water environment and ecological health. Sorting out its pollution characteristics, impact mechanisms and control technologies is of great significance for seeking scientific and effective governance paths. By systematically reviewing, the diversity and impact mechanisms of overflow pollution on water quality characteristics are analyzed. The development process of domestic and international overflow pollution control systems is reviewed. And the application of key technologies such as source control, pipe network system optimization, and end treatment is analyzed in detail. The study result shows that in the future, governance needs to break through traditional models and build a refined system that covers discharge standards, efficiency evaluation and risk management. At the same time, the construction of digital platforms is promoted and an intelligent perception system of "source - network - factory - river" is built, which helps to achieve dynamic early warning and precise facility scheduling, and integrates theoretical framework and technical path, providing theoretical basis and technical support for the comprehensive treatment of combined sewer overflow pollution.
