BIM stands for Building Information Modeling. For civil engineers, BIM is a process that incorporates all the various design disciplines and allows them to create a complete, intelligent model of the infrastructure project. BIM (US site) is the foundation for digital transformation in the civil engineering industry. This process allows engineers to create a more complete representation of project details that can be communicated more efficiently to the design team and to project stakeholders.
For more information, here's a guide to getting started with BIM for civil engineering.