"Installation of power supply in Zhejiang" supports the construction of a cross-river tunnel.

On the morning of March 26th, with the issuance of the starting order, the staff pressed the control panel device start button, and the "Wanmei Electric Power" shield tunneling machine started digging. The construction of the 500kV GIL pipe gallery project in Wuhu, Anhui, has started, creating favorable conditions for the Gansu-Zhejiang 800kV UHVDC transmission project to cross the Yangtze River. The Gansu-Zhejiang 800kV UHVDC transmission project is a key project in the national "14th Five-Year Plan" for power development. The total length of the line is 2370 kilometers, with an annual electricity transmission of 36 billion kWh, of which over 50% is clean energy. When the project crosses the Yangtze River in Wuhu, Anhui, due to limitations of the line corridor, the original 500kV transmission line space needs to be used. Therefore, State Grid synchronously built the GIL pipe gallery to move the original line underground and make space for the project. According to Sun Minggang, the project manager of State Grid Anhui Power Construction Company, the tunneling section of the pipe gallery is 3554.4 meters long, with a maximum burial depth of 53.85 meters. It is constructed using a single slurry balance tunnel boring machine with a cutting wheel excavation diameter of 12.13 meters. The project faces challenges such as ultra-shallow soil cover at the starting point, excavation through rich water sand layers, and long-distance crossing of complex strata, including silt clay, fine sand, round gravel, and moderately weathered limestone. The relevant person in charge of the construction department of State Grid Anhui Power Construction stated that through the three-dimensional construction model of "existing line underground, new line using upper space," efficient use of limited passage resources along the Yangtze River coast was achieved while minimizing the impact on the Yangtze River navigation channel.