(On September 14, the No. 4 Tunnel of Guangzhou Beijiang Diversion Project, a key and difficult project with a total length of 11.4 kilometers, was fully completed.) On September 14, the connectivity infrastructure project of Guangdong Hong Kong Macao Greater Bay Area - the 11.4 km long key and difficult project of Guangzhou Beijiang Water Diversion Project - Tunnel 4 was fully completed, marking the gradual realization of the vision of the people of Guangzhou (prefecture) and Qingyuan (far away) drinking the same river. The project is planned to be fully completed and open to water in April 2024, which will meet the medium and long-term water supply needs of more than 2 million residents in northern Guangzhou. Guangzhou Beijiang Water Diversion Project is a public welfare and strategic water resource security project. It is a major livelihood project for Guangzhou to build a multi water source security water supply security system, improve the emergency standby water source in the central urban area, and solve the water supply needs of Huadu District, Airport Economic Zone, Baiyun District and other northern areas of Guangzhou. The project is composed of Beijiang Water Source Project, new supporting water plant and supporting pipe network. The maximum daily water intake scale is planned to be 1 million cubic meters. The project is planned to be fully completed and put into operation in April 2024, which will improve the four water source complementary water supply pattern in Guangzhou's planning of "West River in the west, Shunde Waterway and Shawan Waterway in the south, North Main Stream and Zengjiang River in the east, and North River and Liuxi River in the north". At that time, it can meet the medium and long-term water supply needs of more than 2 million residents in northern Guangzhou, which is conducive to improving the utilization rate of water resources in Beijiang River, strengthening the security of drinking water in northern Guangzhou, improving the regional water ecological environment, optimizing the allocation of regional water resources, and further promoting the integration of Guangzhou and Qinghai and the economic and social development in northern Guangzhou. Among them, the No. 4 tunnel constructed by China Railway 18th Bureau Group spans Guangzhou City and Qingyuan City. It is a key and difficult project and a key node project along the whole project line. The construction length accounts for 72.6% of the total length of the project, which is characterized by "hard rock, large burial depth, long distance, high pressure", etc. This node project started tunneling on September 7, 2020, and was constructed with the first new open tunnel boring machine (TBM) in China. It is a TBM equipment with the smallest tunneling section, the largest system integration, and the highest customization and personality level in South China. (Liu Xinshe)