As urbanization accelerates, drainage engineering has become a crucial component of urban development, necessitating continuous innovation in technology and concepts to meet the requirements of high-quality urban growth. BIM technology, a key representative of digital innovation, has been widely applied in the design and construction stages of engineering projects. However, its digital and intelligent applications in the operation and maintenance stage remain limited, with most efforts still in the preliminary or conceptual exploration phase. This paper examines the application of BIM in the operation and maintenance of drainage engineering in the context of recent developments in China's digital landscape. By analyzing the core requirements for intelligent operation and maintenance of drainage systems using BIM technology, and through the analysis and practice of several typical drainage engineering model services and intelligent operation and maintenance applications, this study aims to provide valuable insights for leveraging BIM technology in the intelligent operation and maintenance of drainage engineering.