At 1:00 p.m. on November 20, a spillway gate at the bottom of Son La hydroelectric reservoir will be opened.

To reduce the water level of the lake, Son La Hydropower Company will open a bottom spillway gate of Son La Hydropower Lake at 1:00 p.m. on November 20 with a spillway flow of 1,837 m3/s and a total discharge flow through the dam of 4,037 m3/s.

Son La Hydropower Plant opens a bottom spillway gate. (Photo: Quang Quyet/VNA)

On November 20, Son La Hydropower Company issued Official Dispatch No. 2128/TĐSL-KTAT to the Civil Defense Command of Son La province, the Civil Defense Command of Phu Tho province, Hoa Binh Hydropower Company, the Civil Defense Command of Muong La, Muong Bu, Chieng Hoa communes (Son La province) regarding the opening of 1 bottom spillway gate of Son La Hydropower Plant.

To reduce the water level of Son La Hydropower Reservoir, Son La Hydropower Company will open a bottom spillway gate of Son La Hydropower Reservoir at 1:00 p.m. on November 20 with a spillway flow of 1,837 m ³ /s and a total discharge flow through the dam of 4,037 m ³ /s.

Son La Hydropower Company said that based on the regulations on the operation of Son La hydropower reservoir and Bulletin No. 191125HV/DBQG_DBTV dated November 19, 2025 of the National Center for Hydro-Meteorological Forecasting on the 5-day hydrological forecast of the flow to Son La reservoir with the largest water flow to the lake is 2,200 m3/s, average is 1,182 m3/ ^s .

At the same time, at 9:00 a.m. on November 20, the flow to Son La Lake was 1,374 m3/s; the lake water level was at 216.14 m; the machine flow was 852 m3/s.

At the same time, Lai Chau Hydropower Plant is currently opening the spillway to regulate the lake water level, maintaining the water level not exceeding the normal water level of 295m.

According to VNA

Source: https://baohaiphong.vn/luc-13-gio-ngay-20-11-se-mo-1-cua-xa-day-ho-thuy-dien-son-la-527257.html