Shenzhen Dongjiang Water Source Project is a major trans-regional water diversion project solving the problem of water shortage in Shenzhen. The project has been running for 20 years with a total water supply of 10 billion m3 accounting for 40% of the city's domestic water, and has become a lifeline of Shenzhen people. In order to fully grasp the safety status of the project, Shenzhen Dongjiang Water Source Project Management Office commissioned Nanjing Hydraulic Research Institute (NHRI) to conduct a comprehensive safety appraisal of the project.

NHRI attached great importance to the safety appraisal of the project. NHRI vice president DAI Jiqun, working team leader, and Prof. CAI Yuebo, expert team leader, led teams to the project site for investigations many times to determine the overall safety appraisal plan. NHRI Materials and Structural Engineering Department carefully organized and carried out the safety appraisal. In view of the huge difficulties, long period and tight schedule of the safety appraisal, the Department made full use of the one-month water cut-off maintenance period. From March 8 to April 6, 2021, more than 40 experts and technical backbones divided into 9 groups carried out the inspection and special research work at the same time. According to the characteristics of tunnels and pipelines as the main structures of the project and the diversified diseases of the structures, advanced non-destructive testing instruments such as 3D non-contact laser scanner, high- and low-frequency ground penetrating radar, pipeline broken wire detector and underwater detector were applied. Innovative technologies, inventions and methods such as material roughness reduction, image recognition and biological analysis were adopted to evaluate the water supply, water quality and structural safety to find out the hidden dangers of the project and determine the degree of the diseases. In the first water cut-off maintenance period, the on-site safety inspection tasks of 55 water delivery and lifting structures in 106 km project trunk line were completed with high quality, which laid a solid foundation for the next rigorous, realistic, comprehensive and reliable preparation of safety appraisal research achievements.

This safety appraisal project is a hydraulic structure safety appraisal project with the largest contract funding undertaken by NHRI, and is the first application example of safety appraisal for major long-distance water diversion projects across river basins in China after the issuing of SL/T790-2020 Regulations for Safety Appraisal of Hydraulic Tunnels chiefly drafted by NHRI. This safety appraisal project has provided strong technical support for the safe operation and management of major water diversion projects in China with great engineering and research significance.