Unresolved worries about subsidence
As reported by Lao Dong Newspaper, at about 9:34 p.m. on May 26, 2025, in Hiep Luc village, Kim Lu commune, Na Ri district, Bac Kan province, an incident occurred where a young man and a motorbike crashed into a fence and were suspected of falling into a death hole right on National Highway 3B.
After more than 2 weeks of searching with modern technical measures and equipment, the authorities have not yet discovered the victim's whereabouts, due to the complex geology of the sinkhole and constantly fluctuating groundwater, which poses many risks to approach the bottom of the hole.
On June 12, the People's Committee of Bac Kan province officially agreed to stop the search for victims due to not achieving positive results, and at the same time, based on safety concerns for rescue forces in the context of continued subsidence.
Speaking to Lao Dong Newspaper reporter, Mr. Truong Quang Trong - Chairman of Kim Lu Commune People's Committee - said that there are currently a total of 9 locations in the area with signs of subsidence, of which 6 holes have clearly formed, 3 other locations have phenomena of tangled and cracked soil surface. The death hole on National Highway 3B where the serious incident occurred currently shows signs and tends to expand, the groundwater rises abnormally, posing a potential risk of further landslides.
According to the reporter's records in June 2025, many subsidence locations are located close to residential areas, in cultivated land areas. Some areas of the walls and fences of houses were cracked and collapsed, the yard foundation was torn, causing people to live in anxiety and worry.
Having a house about 10m from the death hole on National Highway 3B, Ms. Loc Thi Mai, Hiep Luc village, Kim Lu commune (Na Ri) said that currently, the road and the access to the family's house have begun to show signs of cracking and the soil has sunk.
Local people also said that the phenomenon of cracking soil is spreading to neighboring areas. In particular, many locations around the death hole on National Highway 3B have shown signs of subsidence, some places have land receded to the edge of the yard, and the walls have also begun to crack slightly.
Having a house not far from the death hole, Mr. Trieu Van Ninh, Hiep Luc village, Kim Lu commune, could not hide his concern when witnessing the cline of the hole gradually expanding, seeping into the residential and farming land of the people.
Finding solutions to handle a series of death holes
Faced with the above situation, the Bac Kan provincial government has organized many meetings, inviting experts and specialized units to participate in the survey.
According to the Institute of Geological Sciences and Mineral Resources, the death holes in this area formed on a geological background consisting mainly of strongly dienated limestone, combined with the activity of underground water vessels below.
The prolonged silent erosion process created underground holes, at one point causing a sudden subsidence.With such a complex geological structure, the treatment requires careful survey, avoiding the application of simple hole filling measures that will not be able to solve the problem at the root.
Regarding the handling, Mr. Tran Manh Quyen - Deputy Director of the Road Maintenance Management Board, Bac Kan Department of Construction - said that currently, the area of National Highway 3B through Hiep Luc village has had 2 more large holes on the road surface and 3 other holes within the corridor. The unit has hired a consultant to conduct a geological survey to determine the size of the underground cave below, as a basis for proposing appropriate solutions.
According to Mr. Quyen, there are currently two options: Temporarily filling with common materials if the underground cave is small, or drilling piles, making a concrete floor overcome the hole if the ground structure is not guaranteed. However, all handling decisions must wait for the results of a complete geological survey to ensure long-term effectiveness and safety.
The People's Committee of Bac Kan province has also assigned the Na Ri District Investment and Construction Project Management Board to establish a geological survey project for the entire area of Kim Lu commune, with an implementation period of 45 to 60 days. The survey results will be the basis for proposing long-term stabilization plans, including the possibility of relocating people if necessary.
While waiting for a long-term solution, the area around the sinkhole is still being put up with warning ropes, strictly prohibiting people from accessing them.
