On the morning of March 3, as the cutterhead of the "Ningbo Water No. 1" TBM slowly broke through the rock, the 4-meter-class open-type TBM "Ningbo Water No. 1" (China Railway No. 1362), jointly developed by China Railway Engineering Equipment Group and Zhejiang Tunnel, successfully emerged from the tunnel, achieving full breakthrough of Section I of the Ningbo Reservoir Group East-West Line Connection Project three months ahead of schedule.

The "Ningbo Water No. 1" TBM has an excavation diameter of 4.03 meters, an overall length of approximately 225 meters, and a tunneling length of 10.87 km. Since its launch on March 15, 2024, the TBM has demonstrated outstanding performance. With the close cooperation of the China Railway Engineering Equipment Group service team and the construction unit, the equipment achieved a monthly advance exceeding 1,000 meters for 10 consecutive months, among which the highest monthly advance in December 2024 reached 1,405.4 meters and the highest single-day advance reached 78 meters.

The TBM construction section is adjacent to the Fenghua coastal water supply tunnel and must pass beneath the Jinhai Tunnel, which has been in operation for many years, as well as multiple faults and densely jointed zones. The rock mass in the construction area is fractured, joints and fissures are developed, and the surrounding rock types vary, posing great construction difficulty and safety risks.

To address the construction challenges of the project, China Railway Engineering Equipment Group, drawing on its rich design and manufacturing experience, carried out targeted design of the equipment and incorporated multiple advanced technologies, such as TBM driving attitude monitoring and correction and a wet spraying system and other auxiliary equipment, to adapt to changes in stratum and geology. The unique shield body opening and closing function provides multiple supports for the tunnel during excavation, effectively ensuring the safety and stability of the equipment.

The Ningbo Reservoir Group East-West Line Connection Project is a key water conservancy project in Ningbo, aimed at optimizing regional water resource allocation and enhancing water supply guarantee capacity. Once completed, the project will further improve Ningbo's modern "water network," effectively realize interconnection and joint dispatch among multiple water sources, and be of great significance for solving the problem of unbalanced water resources between the east and west lines of Ningbo and achieving east-west mutual water supply support.