Since the 14th Five-Year Plan，China has officially entered the digital era.The intelligent application of water conservancy projects in the construction period has been widely promoted.At present，the application of engineering wisdom is still rarely involved in the operation stage with the longest life cycle and the highest cost.This paper takes the Pearl River Delta project as an example to explore the intelligent application of large-scale water conservancy projects in the operation period.Based on BIM+GIS，cloud computing，Internet of Things technology，and big data of operation and maintenance business，this paper focuses on intelligent application construction，digital twin platform construction，engineering big data center construction，basic environmental facilities construction，construction of integrated management and control system，and enhancement of network security system to plan the intelligent application construction programme of the Pearl River Delta project during the operation period.The results provide intelligent application solutions for intelligent water conservancy projects during the operation period，and provide practical reference for the construction of intelligent water conservancy projects with unattended，closed operation，rapid water supply，economic water supply，power-saving water supply，and high-quality water supply.