On April 10, the Qinghai Jiaxi Highway project, invested in and jointly constructed by Sinohydro Bureau 4, achieved a major milestone—the right tube of the Huzhu Beishan Extra-Long Tunnel was successfully holed through. This not only marks key progress in the project's construction but also lays a solid foundation for completing the entire project on schedule.

The Jiaxi Highway is an important component of National Highway 341 (Jiaonan–Haiyan Highway) in the national highway network plan, and is a key planned construction project in Qinghai Province's 13th Five-Year Plan for transportation, with a total length of approximately 214.72 kilometers. The Huzhu Beishan Extra-Long Tunnel is located in Huzhu Tu Autonomous County, Haidong City, Qinghai Province, starting at Yuanfugou and ending at Baimuxiakou. With a right-line length of 11,126 meters, it is one of the key control works of the Jiading–Xihai Highway and the longest highway tunnel in Qinghai Province, ranking second among China's extra-long tunnels in high-cold and high-altitude regions. The tunnel passes through the Huzhu Beishan National Forest Park and Geopark, where the ecological environment is highly sensitive. The maximum buried depth at the tunnel floor reaches 769 meters, and the project faces complex geological conditions such as high ground stress, large deformation, and the need to cross 7 fault fracture zones, posing extremely high construction risks and difficulties.

Since construction began in 2020, the construction team has faced numerous challenges. To address ecological disturbance and environmental damage caused by construction operations, the team adhered to the construction organization principle of "permanent-temporary integration," earning recognition from environmental protection authorities and all sectors of society. During construction, the team strictly followed the construction principles of "advance detection, advanced pipe roofing, short advance, weak blasting, strong support, early closure, and frequent measurement," adopted advanced techniques and equipment, and used means such as advanced geological forecasting and monitoring measurement to predict geological conditions in advance and take pre-reinforcement measures. They successfully crossed 7 fault fracture zones and other unfavorable geological sections, solved numerous construction challenges such as ventilation and smoke exhaust, surrounding rock deformation, and reverse-slope drainage, and ensured smooth progress of construction.

At present, construction of the left tube is progressing steadily as planned, and the two tubes are expected to be holed through by the end of April 2025. Once completed, the Jiaxi Highway will be of great significance in accelerating the development and outward transport of resources in western Qinghai, strengthening ethnic unity, and supporting national defense construction.