A car stalled in the middle of the tunnel, vehicles behind had to turn around. The traffic direction from the Ho Chi Minh City - Long Thanh - Dau Giay expressway to Mai Chi Tho through the tunnel had to be temporarily closed for handling.
This is not the first time.
In February 2026, tunnel HC1-02 was flooded about 50cm due to an electrical incident that caused the pumping station to stop operating, and groundwater flowed back into the tunnel.
This time, heavy rain caused water from outside to overflow, even the pumping station was flooded, directly affecting the drainage capacity.
A project that has just been put into operation and has faced flooding twice is an issue that needs to be viewed directly.
It is not necessary to hastily attribute poor quality works to just a few heavy rains, but it is also impossible to use the reason "too heavy rain" to let things pass.
The underpass is built for vehicles to pass through the ground, so the ability to resist water, collect water, pump water and operate the cylinder in heavy rain conditions must be the core requirement of the project.
Therefore, what people need is not an explanation for the submerged tunnel, but a solution to prevent the tunnel from continuing to flood.
The Traffic Board has requested the construction unit to build a system surrounding the pumping station to prevent water from outside from overflowing. This is something that needs to be done immediately, but that is still not enough.
It is necessary to comprehensively check the drainage capacity of HC1-02, from altitude, water intake direction, intake gate, drainage culvert, tank, capacity and operating mode of the pump to backup power source.
In particular, extreme rain scenarios must be checked, not just checked in normal weather conditions.
A pumping system placed in an area at risk of water overflowing without adequate protection is no different from placing the "heart" of the drainage system in the most vulnerable place.
The lesson from the February incident further shows that the drainage system of the tunnel cannot depend on a single link.
Encountering electrical problems, broken pumps or water overflowing into the pumping station can turn a traffic project worth hundreds of billions of VND into a bottleneck.
An Phu intersection is expected to solve congestion at the eastern gateway, synchronously connecting with many other important traffic routes.
Therefore, the quality of the project must be placed higher than the traffic opening progress. Because, safe and stable exploitation through many rainy seasons is the final measure.
A traffic project cannot operate in the style of "flood control as it rains".
Rain is the most stringent test for the quality of the project.
And, with the HC1-02 tunnel, the most important acceptance document at this time is not on paper, but must be based on reality, heavy rain still ensures safe traffic.
