Picture 1. Celebration of the Entire Excavation 1

Picture 2 Celebration of the Entire Excavation 2 

　　On September 29, 2021, the entire excavation of the Diversion Tunnel of CHMC Laos Nam Ngum 4 Hydropower Station Project，was completed. The Diversion Tunnel is totally 17551 meters in length, and eight construction branch tunnels are set up on the whole line. Since the excavation began on July 28,2017. After nearly four years work, it was completed, achieving another major milestone node in the construction of the Project.

　　The geological and hydrological conditions of the tunnel are complex and the stability of the surrounding rock is poor. The construction is very difficult and at high risk. The Project Department overcame the adverse impact of personnel allocation and material transportation caused by the COVID-19 epidemic, and strictly observed the construction safety and quality to ensure the smooth implementation of the project

　　The full excavation of the diversion tunnel laid a solid foundation for the subsequent construction work of the Project.