Due to the circulation of Typhoon No. 4, heavy rainfall has caused water levels on the Luc Nam, Thuong and Ky Cung rivers to rise. From August 23 to 25, flood peaks on the Thuong, Luc Nam, Thai Binh (Hai Phong), Trung, Ky Cung, Bac Giang (Lang Son), Bang Giang (Cao Bang), and Cau (Thai Nguyen) rivers are forecast to reach Alert Level 2–3, with some rivers exceeding Alert Level 3.

To proactively respond to Typhoon No. 4 and associated flooding, authorities at both central and local levels have implemented coordinated measures under the “four on-the-spot” principle, ensuring timely and practical actions focused on safeguarding lives and property.

The Prime Minister issued Official Dispatch No. 57/CD-TTg dated August 21, 2026, and Official Dispatch No. 54/CD-TTg dated August 17, 2026, requesting chairpersons of provincial and municipal People's Committees in northern provinces, from Thanh Hoa to Quang Tri, as well as ministries and sectors, to proactively respond to natural disasters, heavy rainfall, flash floods and landslides, while accelerating post-disaster recovery efforts.

On August 22, 2026, the National Civil Defense Steering Committee issued Official Dispatch No. 46/BCD-BNNMT on proactive flood response. Earlier, on August 21, it issued Official Dispatches No. 44/BCD-BNNMT and No. 45/CD-BNNMT-DD, directing responses to the tropical depression in the East Sea of Viet Nam, Typhoon No. 4 and heavy rainfall.

The Ministries of National Defense, Public Security, Construction, Education and Training, Science and Technology, and Industry and Trade also issued directives requiring subordinate units to remain prepared for typhoons, tropical depressions, heavy rainfall, floods, inundation, flash floods and landslides in northern Viet Nam and the area from Thanh Hoa to Ha Tinh.

On August 22, 2026, the Ministry of Agriculture and Environment issued Official Dispatch No. 9680/CD-BNNMT ordering the closure of one bottom outlet gate of Hoa Binh Hydropower Reservoir at 4:00 p.m. the same day. It also issued Document No. 9681/BNNMT-DD to the provinces and cities of Phu Tho, Hanoi, Bac Ninh, Hai Phong, Hung Yen and Ninh Binh on ensuring downstream safety during reservoir operations.

On the same day, the Vietnam Disaster and Dyke Management Authority (VDDMA) issued Document No. 1588/DD-QLDD to the Departments of Agriculture and Environment of Bac Ninh, Thai Nguyen and Thanh Hoa, requesting urgent implementation of dyke safety measures and flood response actions along the Thuong, Luc Nam, Cau and Buoi rivers. The Authority also deployed two field missions to support Typhoon No. 4 response efforts in Quang Ninh Province and inspect dyke sections along the Thuong and Luc Nam rivers in Bac Ninh Province. In coordination with Zalo Vietnam, VDDMA sent two rounds of warning messages on vessel safety and disaster preparedness to 11.6 million subscribers in Son La, Phu Tho, Thai Nguyen, Cao Bang, Lang Son, Quang Ninh, Bac Ninh and Thanh Hoa, as well as coastal communes in Quang Ninh, Hai Phong, Hung Yen and Ninh Binh. Round-the-clock duty operations have been maintained to monitor weather, disasters and dyke conditions and promptly provide forecasts and warnings to local authorities.

At the local level, Bac Ninh, Lang Son and Quang Ninh provinces organized inspection missions to assess preparedness and response activities while mobilizing local resources to support affected households. Local authorities issued official dispatches and directives on typhoon and heavy rainfall response, maintained emergency duty rosters, and closely monitored weather developments and warning information.

To ensure public safety, local authorities evacuated a total of 2,383 households, including 2,335 households in Lang Son Province (211 households in Huu Lung and 2,124 households in Ky Cung, including 733 flood-affected households), 31 households in Quang Ninh, 17 households in Bac Ninh and 121 households in Thanh Hoa. Guard posts and traffic control measures were established in areas at risk of deep flooding and landslides to minimize losses caused by the storm and flooding.

As of 7:00 a.m. on August 23, 2026, preliminary damage assessments in Lang Son, Quang Ninh and Bac Ninh indicated that Typhoon No. 4 and heavy rainfall had caused one fatality. The victim, Mr. Duong Phuc Hinh, born in 1999 and residing in Thai Binh Commune, Lang Son Province, died when a landslide struck his house.

Housing damage included 200 houses damaged or with roofs blown off and 733 houses inundated, all in Lang Son Province. In agriculture and forestry, approximately 2,864 hectares of crops were flooded or damaged, including 1,100 hectares in Lang Son, 1,687 hectares in Bac Ninh and 78 hectares in Quang Ninh. Livestock losses in Lang Son included 100 head of livestock and 6,000 poultry. Transportation infrastructure was also affected, with 603 landslide and flooding points causing traffic disruptions, including 600 locations in Lang Son and three in Bac Ninh.

Local authorities are continuing to review and consolidate damage assessments.

The following are some photos showing flooding and inundation in Lang Son Province: