Overnight on September 29 and into the early hours of September 30, Hanoi and various provinces in the north and north-central regions such as Lao Cai, Thai Nguyen, Phu Tho, and Thanh Hoa recorded heavy rainfall, with levels commonly ranging from 50 to 100mm. Some locations experienced significantly higher rainfall, including Yen Binh (Lao Cai - 148mm), Hoang Nong (Thai Nguyen - 198mm) Huu Loi (Phu Tho - 182mm), Thanh Hung (Thanh Hoa - 272mm), and Quoc Oai (Hanoi - 138mm).

Floodwater levels are rising rapidly on rivers from Lao Cai to Ha Tinh province. As of 7:00 a.m. on September 30, the water level of the Thao River in Yen Bai had exceeded flood alert level III by 2.28 meters. The Hoang Long River in Ninh Binh was 0.03 meters above level III, while the Lam River in Nghe An exceeded alert level III by 0.20 meters. These sharp increases have raised serious concerns, particularly for midland, mountainous, and downstream areas of major rivers.

In response to rising inflows, several large hydropower reservoirs have begun discharging water to ensure the safety of their structures and to regulate downstream flood risks. Specifically, the Tuyen Quang hydropower plant is releasing water through seven bottom outlets, the Hoa Binh hydropower plant has opened two bottom outlets, and the Thac Ba reservoir is discharging through two surface gates. These discharges are significantly increasing water volumes in downstream river systems.

In Thanh Hoa province, major rivers such as the Ma, Chu, Buoi, Cau Chay, Yen, and Len rose to alert levels I to III, causing severe flooding. Many homes in both outer and inner dyke areas are now submerged under 1 to 2 meters of water.

On September 30, in several areas of Quy Chau district, Nghe An province, floodwaters surged rapidly, inundating residential areas and roads, cutting off access to many villages. Numerous homes were submerged up to their rooftops.

In Lao Cai province, rainfall over the past 24 hours ranged from 100 to 200 mm in many places, with some areas recording over 300 mm. Water levels on the Thao River swelled up rapidly, exceeding alert level III, resulting in widespread and serious flooding in multiple localities and directly affecting thousands of households.

According to the National Centre for Hydro-Meteorological Forecasting, river levels in the northern and north-central regions are anticipated to continue rising on September 30 through October 1. Peak flood levels on the Hoang Long River and other small rivers may reach or exceed flood alert levels II to III. Flood peaks on the Lo River in Tuyen Quang, the upper Thai Binh River in Thai Nguyen and Bac Ninh, and the lower La River in Ha Tinh are expected to reach levels I to II, with some areas surpassing level II.

Although typhoon Bualoi has already moved into Laos, its residual circulation continues to bring heavy rainfall across large areas of Vietnam. Dr. Mai Van Khiem, director of the National Centre for Hydro-Meteorological Forecasting, warned that persistent rainfall in recent days, coupled with expected continued precipitation on September 30, has left soil moisture in the northern midlands and north-central mountainous regions fully saturated. This significantly increases the risk of flashfloods and landslides in mountainous and hilly areas, as well as floods along rivers and streams in the affected regions.

These hazards will not only persist throughout September 30 but may continue for the next two to three days, he said.

Given the high rainfall and rising floodwaters, many river systems could experience a spell of significant flooding, with levels reaching or exceeding alert levels II to III. He warned of a heightened risk of deep and widespread flooding in riverside areas and downstream regions, particularly in provinces such as Ha Tinh, Nghe An, and Thanh Hoa.

Local authorities are urgently implementing response measures, including the evacuation of residents from high-risk areas vulnerable to landslides, flashfloods, and deep inundation. Residents are advised to avoid traveling through flooded areas and landslide-prone zones to ensure safety.

Typhoon Bualoi leaves 19 dead, 13 missing in Vietnam

VOV.VN - As of the evening of September 29, Typhoon Bualoi has left at least 19 people dead, 13 missing, and 89 injured across various provinces in Vietnam, mainly in the central region, according to the Ministry of Agriculture and Environment.