On May 19, the Zhangjiapo Tunnel of the Chongqing Yuxi Water Resources Allocation Project, constructed by Sinohydro Bureau 9 Co., Ltd., was successfully holed through, marking the completion of all tunnels of the project and laying a solid foundation for the full completion of the subsequent works.

The Yuxi Water Resources Allocation Project is one of the 150 major water conservancy projects in China, and also a major livelihood water conservancy project in Chongqing with the largest investment, the widest coverage and the largest beneficiary population. The project has a total of 23 tunnels with a total length of 81 kilometers. The Zhangjiapo Tunnel holed through this time has a total length of 14.13 kilometers, extending north to the Yutan Reservoir in Dazu District and south to the Huangjinpo Booster Station in Rongchang District, with its inlet connected to a covered culvert and its outlet connected to a distribution pond. The main tunnel body has a gate-shaped cross-section. Once completed, it can deliver nearly 260,000 cubic meters of water per day to Rongchang District, with an annual average of 95 million cubic meters, benefiting more than 600,000 people.

During construction, Party members of the project department took the lead in driving young commando teams, actively carried out scientific and technological innovation and technical research, adopted a construction process combining mechanical excavation with a cantilever roadheader and the drill-and-blast method, applied advanced geophysical prospecting technology for complex geology in long-distance tunnels and an intelligent management system, innovatively researched and used a construction method for large-flow sewage treatment in tunnels and a tunnel dewatering method combining a permeable floor layer with drainage blind pipes, and overcame difficulties such as shallow tunnel cover, relatively complex geological conditions, and passing through multiple strata and several fault zones, thus successfully achieving the goal of tunnel holing-through.

After the entire project is completed, water will be pumped from the Yangtze River and the Jialing River to supply domestic and industrial water to urban and rural areas in western Chongqing, realizing interconnection and mutual regulation and supplementation between Yangtze River water and Jialing River water. The benefited area will reach 11,800 square kilometers, effectively guaranteeing the domestic and industrial water demand of 10 million people in urban and rural areas of western Chongqing, and solving the problem of the lack of large high-quality water sources in the Chengdu-Chongqing economic circle.