The project to build an underpass on the Ring Road 2.5 through the Kim Dong - Giai Phong intersection (Hanoi) started construction in October 2022.
The total length of the tunnel and approach road is 890m in the direction of Ring Road 2.5, of which the closed tunnel is 140m long and the open tunnel is 320m long. The section through the tunnel has 2 lanes each way, 3.5m wide/lane, the section outside the tunnel has 3 lanes each way, 3.5m wide/lane.
The underpass project has a total investment of 778 billion VND, invested by the Hanoi Traffic Construction Investment Project Management Board.
This is the 5th underpass in the capital built from 2009 to present, after the Kim Lien, Trung Hoa, Thanh Xuan, and Le Van Luong tunnels.
Speaking to reporters, Mr. Nguyen Dinh Trang - Deputy Director of the Cienco4 Contractor Executive Board, the construction unit of the Kim Dong - Giai Phong underpass, said that after more than 3 years of construction, the underpass project has reached about 75% of the workload.
The unit is mobilizing dozens of workers and many modern machines to continuously construct 3 shifts on the construction site to deploy the burning of the 5th closed tunnel out of a total of 8 tunnel segments.
For the 3 tunnels passing through the railway, the unit is digging and preparing to pour reinforced concrete structure, expected to be completed by the end of November.
According to Mr. Trang, the tunnel sections on the Dam Hong and Kim Dong sides have been basically completed. Currently, the unit is completing the route items and works on the route to connect technical infrastructure with Dinh Cong Street.
According to Mr. Trang, within the project scope, there is still a location of a house that has not been cleared in Dinh Cong ward. The construction unit has requested the local government to completely handle this site clearance plan to have a construction site for the completion of technical infrastructure works and road surface along both sides of the tunnel.
Mr. Ngo Van Thien - Chief Supervisory Advisor of the Kim Dong underpass project said that the quality management of the project is strictly implemented, strictly complying with the provisions of the law.
According to Mr. Thien, by the end of December 2025, the project will be basically completed and can be put into operation in the first quarter of 2026.
However, problems with site clearance are affecting the project's progress. In addition, the implementation of underground tunnel burning under the railway line that is still operating only allows construction of about 2 hours per day, which is also a difficulty for the contractor.
Along with the Kim Dong - Giai Phong underpass project, the progress of the Ring Road 2.5 construction project, Dam Hong - National Highway 1A section, is also being accelerated after many years of delay due to land clearance problems and extension of the BT contract appendix.
The project was restarted at the end of May 2025 after many years of stagnation. Currently, Hoang Mai - Hanoi Construction Investment Company Limited (project enterprise) is mobilizing many machines and human resources to speed up the construction progress, completing the entire 1.6km long route by 2026, synchronized with the Kim Dong - Giai Phong underpass.
