In order to solve the problems of large engineering volume, short design cycle, heavy modeling tasks and frequent route adjustment encountered in the rapid channel project from Liangjiang New Area to Changshou District (hereinafter referred to as Jiangchang Project), the secondary development is carried out for BIM design software based on Autodesk platform. The realized functions are the rapid creation of large-scale site models, the rapid transformation of traditional design results, that is, the analysis of EICAD data and the automatic generation of C3D route objects, the high-quality creation of BIM model, that is, the automatic creation of large-scale bridge and tunnel models, and the application of coding tools. Through the comprehensive application of the above tools, an application process suitable for BIM design of super-large municipal project is explored, which lays a solid foundation for promoting BIM forward design of municipal projects.