According to records at 10:00 AM on September 11, underpass HC1-02, the section connecting Mai Chi Tho street with the Ho Chi Minh City - Long Thanh - Dau Giay expressway, is still flooded and vehicles are not allowed to circulate.
On the same morning, the Ho Chi Minh City Traffic Construction Investment Project Management Board (Traffic Board) coordinated with contractors and functional forces to mobilize many pumps to the scene to pump water out.
The submerged tunnel section is about 300 m long. The Fire and Rescue Police Team of Area 2 mobilized specialized vehicles and pumps to support drainage. Ho Chi Minh City Urban Drainage Company also dispatched mud suction trucks to the scene for handling.
Two large capacity pumps continuously pump water from inside the tunnel to the Song Hanh road area.
By 10:30 am, water in the An Phu underpass had not been pumped out. Two directions of traffic through the tunnel continued to be blocked to ensure safety.
The closure of the underpass affects traffic at An Phu intersection - the connecting point of Mai Chi Tho, Luong Dinh Cua, Dong Van Cong roads with the Ho Chi Minh City - Long Thanh - Dau Giay expressway.
Functional forces are deployed to divert and regulate traffic. Thousands of vehicles from the Ho Chi Minh City - Long Thanh - Dau Giay expressway heading towards An Phu intersection had to line up in long lines.
According to the usual route, cars from the highway can pass through the HC1-02 underpass to get to Mai Chi Tho street and into the center of Ho Chi Minh City. When the tunnel is closed, the flow of vehicles must concentrate in the roundabout area, causing prolonged congestion.
HC1-02 underpass was deeply flooded after a heavy rain in the late afternoon of September 10. At many locations, the water rose about half a meter. A car stalled while moving from the Ho Chi Minh City - Long Thanh - Dau Giay expressway towards Mai Chi Tho street.
Immediately after the flood occurred, the traffic direction from the Ho Chi Minh City - Long Thanh - Dau Giay expressway to the An Phu intersection through the HC1-02 tunnel was temporarily closed for handling.
According to a representative of the Traffic Management Board, the rainfall in the evening of September 10th was very heavy, while water from outside overflowed into the tunnel area, causing the drainage system to not have time to drain.
Notably, water also overflowed into the pumping station serving the tunnel, affecting the operation of the drainage system and making flood treatment difficult.
The HC1-02 underpass has a total investment of more than 342 billion VND, and is one of the important items of the An Phu intersection project. The project was opened to traffic on February 2, 2026.
The tunnel is about 480m long, of which more than 140m is closed tunnel and more than 340m is open tunnel. The tunnel's starting point is adjacent to the beginning of Ba Dat bridge, the ending point is on Mai Chi Tho street, connected to the HC1-01 tunnel access road. The project has a scale of two-way traffic, two lanes in each direction.
This is not the first time the HC1-02 underpass at An Phu intersection has been flooded. On the morning of February 16, 2026, the tunnel was flooded about 50cm deep.
According to functional agencies, the cause at that time was an electrical incident that caused the pumping station to stop operating. Groundwater flowing back into the tunnel led to flooding.
An Phu intersection was started at the end of 2022 with a total investment of more than 3,400 billion VND, built on a three-story scale including an underpass and an overpass system.
The project has been postponed twice. Initially, the project was expected to be completed by the end of 2025, then postponed to the second quarter of 2026 and now continued to be adjusted to the second quarter of 2027, expected to be handed over in the third quarter of 2027.
