On May 14, a ceremony was held to mark the double-tube breakthrough of the Lehua Tunnel on the Ledu-Hualong section of the G213 Ceke-Mohan Highway. The Lehua Tunnel is located in Qutan Town, Ledu District, Haidong City, Qinghai Province, and Bayan Town, Hualong Hui Autonomous County. It is one of the main routes connecting Ledu and Hualong, with a total route length of 53.59 kilometers. Construction of the project began in August 2020, with the Ledu-Qutan section completed and opened to traffic by the end of 2022. The Qutan-Hualong section is currently under construction and is scheduled to be completed and opened to traffic within 2024.

The right tube of the tunnel in this project broke through on April 7, 2024, and the left tube broke through on May 10, 2024.

The Lehua Tunnel is the highway tunnel with the greatest burial depth in Qinghai Province and the third-longest tunnel in the province, featuring high construction difficulty and high safety risk. The tunnel has a total length of 5,933 meters, with an elevation of 3,100 meters at the entrance and 3,200 meters at the exit. The geological and hydrological environment is complex, with adverse geological phenomena mainly including fault fracture zones, extremely high in-situ stress, and seasonally frozen soil. During excavation, the tunnel passed through fault fracture zones five times.

Since the start of construction, all project participants have overcome a series of difficulties, including the severe cold and oxygen deficiency at the construction site, the complex and water-rich geological conditions of the tunnel, the great difficulty of construction management, and the high environmental protection requirements. In only three and a half years, they completed nearly 6 kilometers of excavation, creating the "Lehua speed" of high-quality tunnel construction in the province.

According to reports, to ensure that tunnel construction quality, safety, environmental protection, and progress remain controllable, the project team planned ahead, tackled difficulties, and adopted multiple measures to build a "quality tunnel." They took the lead in promoting six major informatization systems for tunnel safety management to ensure all-time, multi-level monitoring of tunnel construction. In water-rich sections, construction adhered to the principle of "probe whenever in doubt, probe before excavation, and combine plugging with drainage." In sections with relatively good surrounding rock, smooth blasting was actively promoted to control overbreak and underbreak, reduce disturbance to the surrounding rock, and improve the stability of the tunnel face and the safety of tunnel construction, ensuring that tunnel quality, safety, environmental protection, and progress meet requirements.

Once the Lehua Expressway is completed, it will form a regional expressway network, promote interconnectivity between Haidong City and its counties and districts, and give full play to the benefits of the expressway network. It is of great significance for improving Qinghai Province's space for external development, improving transportation conditions in impoverished areas along the route, enhancing its radiation capacity, and promoting tourism development at Qutan Temple.