On September 6, the Yujia Tunnel on the Dahejia (Gansu-Qinghai border) to Qingshui section highway was fully holed through in both tubes, laying a solid foundation for the year-end opening to traffic of the provincial expressway linking Chuanda and Linda.

The reporter learned from Qinghai Provincial Transportation Holding Group Co., Ltd. that the Yujia Tunnel, with a total length of 1,502 meters, runs along the north side of the Yellow River. The area it passes through has a fragile ecology, and the tunnel consists entirely of Grade V surrounding rock. The geological conditions in the tunnel area are complex, with adverse conditions such as shallow cover and asymmetrical loading, and the tunnel passes beneath a 330 kV high-voltage transmission tower. Construction safety risks are high and environmental protection pressure is great, making it a key, difficult and controlling project on the entire line. To ensure construction safety and project quality, the project department repeatedly invited experts to organize scheme review meetings, continuously optimized the design and construction plans, improved the risk control system, and adjusted construction techniques and methods, ensuring the smooth holing-through of both tubes of the tunnel.

The Daqing Highway project starts at Guanting Town, Minhe Hui and Tu Autonomous County, Haidong City, connecting with the already completed Chuankou to Dahejia Expressway, and ends on the south side of Qingshui Township, Xunhua Salar Autonomous County, Haidong City, where it connects through a hub interchange with the already completed Dalijiashan to Xunhua Expressway. It is an important connecting line of Horizontal Line 3 in Qinghai Province's planned "three vertical, four horizontal and ten connecting" expressway network and of Connecting Line 3 in the "six vertical, nine horizontal and twenty connecting" trunk highway network, and is another interprovincial express corridor between Qinghai and Gansu provinces. The highway has a total length of 29.443 kilometers and is built to the standard of a two-way, four-lane expressway.