Wedoany.com Report on Mar 10th, Recently, the drainage tunnel project for Zhangzhou Nuclear Power Plant in Fujian, undertaken by CCCC Fourth Harbor Engineering Co., Ltd., successfully completed the tunneling construction of Tunnel No. 4, with the shield machine reaching its designated position.

Drainage Tunnel No. 4 for the Zhangzhou Nuclear Power Plant Project in Fujian

This project is a key benchmark project in China's nuclear power layout along the Fujian coast. The drainage tunnels for Units 3 and 4, as core supporting facilities for the nuclear power units, bear the important function of discharging cooling water. Among them, Drainage Tunnel No. 4 has a single tunnel length exceeding 5,200 meters. The tunneling construction directly faced three challenging geological conditions: shallow overburden, boulders, and a composite stratum with soft upper layers and hard lower layers. The project team overcame difficulties such as severe shield cutter wear, frequent pressurized cutter replacements, challenges in maintaining pressure in the ultra-shallow overburden section of the marine area, and grout leakage to the sea surface. They also managed to meet the millimeter-level settlement control requirements for three undercrossings of the diversion dike, successfully completing the milestone task with high quality.

Upon completion, the circulating cooling water from the nuclear power units will be discharged into deep-sea areas via the drainage tunnels, reducing the impact of seawater temperature rise on the coastal marine environment. This will provide strong support for the smooth operation of two million-kilowatt-class nuclear power units, contributing to the development of China's nuclear power industry and energy transition.