Abstract: The second phase of the Futian Water Purification Plant project is committed to achieving the goal of green, low-carbon, energy-saving and consumption-reducing development, and implementing new development concepts throughout the entire process from design to construction. The project is a large-scale project and is the largest double-layer semi-underground water purification plant in Asia. It must adopt BIM technology application and green construction. The project takes the three-dimensional geological BIM model as the starting point, and combines the three-dimensional geological BIM model with the pile length verification technology of Dynamo technology to guide the design and construction of pile foundations and reduce carbon emissions during the construction process. At the same time, the project installs a solar photovoltaic power generation system on the roof of the office area After adopting these measures, the project is expected to save more than 20 tons of CO2 emissions per year. This project has certain reference value for the digitalization and low-carbon application of water purification plants.