As of 8:00 a.m. on December 4, 2025, according to an update from Vietnam Electricity Group, Hoa Binh Lake recorded upstream water levels at elevation of 116.62m; water flow to the lake reached 1,135m3/s; total discharge was 1,698m3/s.
Implementing the inter-reservoir operation process in the Red River basin, Hoa Binh Hydropower Plant closed the bottom spillway at 9:00 p.m. on November 24, 2025. After closing the spillway, the water flow downstream decreased rapidly.
At Tuyen Quang Lake, by 7:00 a.m. on December 4, the upstream water level reached 119.12 m; the water flow to the lake reached 118 m3/s; the total discharge was 114.14 m3/s.
Implementing the inter-reservoir operation process on the Red River basin, Tuyen Quang Hydropower Plant has closed 1 bottom spillway gate of Tuyen Quang Hydropower Plant, currently only maintaining power generation through generators.
As of 8:00 a.m. on December 4, Son La Lake recorded upstream water levels at 214.47 m; water flow to the lake was 935 m3/s; total discharge was 1,491 m3/s. Currently, the unit has closed all bottom spillways, only maintaining power generation through generators to regulate the flow downstream.
A similar situation occurred in Lai Chau Lake, where the upstream water level reached 293.92m; the water flow to the lake reached 694m3/s; the total discharge was 1,104m3/s. Currently, Lai Chau Hydropower Plant has also closed all spillways and surface spillways, only operating power generation through generators.
At Thac Ba Lake, as of 8:00 a.m. on December 4, the upstream water level reached 57.75 m; the water flow to the lake reached 135 m3/s; the total discharge was 272.35 m3/s. Currently, Thac Ba Hydropower Plant also maintains the closure of all spillways and surface spillways.
Up to this point, all large hydroelectric reservoirs in the North have simultaneously closed to release water, showing that the water source situation has stabilized, creating conditions to ensure safety downstream and maintain stable power production.
According to the National Center for Hydro-Meteorological Forecasting, today, December 4, cold air continues to affect the Northeast and North Central regions, then affects the Northwest and North of the Central Central region. On land, the Northeast wind will be strong at level 2-3, and coastal areas will be strong at level 3-4.
In the Northern and North Central regions, there will be scattered rain and light rain. Cold weather, some mountainous areas of the North are very cold. The lowest temperature in this cold air mass in the Northern and North Central regions is generally from 15-18 degrees, in the mountainous areas of the North, it is generally from 13-15 degrees, in some places below 12 degrees.
The Hanoi area will have scattered rain and light rain. Cold weather. The lowest temperature in this cold air mass is generally 15-18 degrees Celsius.
Due to the influence of the strengthening cold air combined with the weakening of the low pressure area from storm No. 15, above is the disturbance in the East wind zone, so in the area from South Quang Tri to Da Nang, the East of the provinces from Quang Ngai to Dak Lak and Khanh Hoa, there will be moderate rain, heavy rain over a wide area.
