Heavy rain over large areas in Da Nang, hydroelectric reservoirs begin to discharge water

(Chinhphu.vn) - On the morning of October 26, the Central Region Hydrometeorological Station issued a flood warning for Da Nang city (from October 26 to 29). Hydroelectric reservoirs began releasing water this morning.

According to the update of the authorities, currently some temporary bridges on the road to Tra Lien commune, Da Nang city are flooded due to heavy rain.

Floods on rivers rise to alert level 2

The update at 9am on September 26 of the Central Hydrometeorological Station said that in the past 24 hours in Da Nang city, there was rain, moderate rain, heavy rain to very heavy rain in some places. The total amount from 7am on October 25 to 7am on October 26 was generally 30-100mm, higher in some places such as: Tra My 145.2mm, Tam Tra 144.8mm, Tra Don 74mm. Heavy rain concentrated from last night to this morning.

Heavy rain forecast in the next 24 to 48 hours: Wards and communes in Da Nang city will have moderate rain, heavy rain, and some places will have very heavy rain and thunderstorms. Total rainfall in wards and communes in the plains and northwest mountainous areas is generally 150-350 mm, some places over 450 mm; in wards and communes in the southern mountainous areas is generally 200-400 mm, some places over 500 mm.

Currently, water levels on rivers in Da Nang city are fluctuating and below warning level (BĐ)1.

Warning: From today (October 26) to October 29, there is a possibility of a flood on rivers in Da Nang city. The flood peak on Vu Gia-Thu Bon river fluctuates at level BĐ1 to BĐ2, some places above BĐ2; Han river and Tam Ky river are at level BĐ1 to BĐ2.

Risk of flooding in low-lying areas along rivers, flooding in urban areas, flash floods, landslides on steep slopes in mountainous areas of Da Nang city.

Dak Mi 4 Hydropower Plant discharges from 500 m3/s to 2500 m3/s through the spillway.

On the same morning, Dak Mi Hydropower Joint Stock Company announced an increase in the regulated flow through the spillway of Dak Mi 4 Hydropower Reservoir. Accordingly, the expected start of operation is from 9:00 a.m. on October 26, the expected regulated flow through the spillway is: 500 m3/s to 2,500 m3/s.

Song Tranh Hydropower Company also announced the operation of Song Tranh 2 Hydropower Reservoir. Expected start time of operation: from 11am on October 26, the flow regulated through the spillway is expected to be from 10 to 1490 m3/s (depending on the water flow to the reservoir).

A Vuong Hydropower Joint Stock Company also announced the spillway operation to ensure the reservoir water level is not higher than 372 m. Accordingly, at the time of operation at 2:00 p.m. on October 26, the expected spillway flow is from 25 to 600 m3/s.

Change the operating mode according to the provisions of Procedure 1865 of the Prime Minister

On the same morning, the Da Nang City Civil Defense Command also issued a dispatch requesting hydropower companies to regulate and lower water levels.

Accordingly, the water levels of hydroelectric reservoirs at 5:00 a.m. on October 26 (Dak Mi 4: 253.09m; Song Bung 2: 594.34m; Song Bung 4: 215.23m; A Vuong: 370.96m; Song Tranh 2: 166.24m) and the water levels at the hydrological stations Hoi Khach, Ai Nghia, Nong Son, and Cau Lau are all below level 1.

The Head of the Da Nang City Civil Defense Command requested Song Bung Hydropower Company to proactively calculate and organize operations to ensure that the water level of Song Bung 2 and Song Bung 4 hydropower reservoirs is not higher than the lowest flood level. Operation will start at 12:30 on October 26. Switch to the operating mode according to the regulations of Procedure 1865.

Dak Mi Hydropower Joint Stock Company, A Vuong Hydropower Joint Stock Company, and Song Tranh Hydropower Company proactively calculate and organize operations to ensure that the water level of hydropower reservoirs is not higher than the water level elevation: Dak Mi 4: 253.5m; A Vuong: 372m; Song Tranh 2 168m. Switch to operating mode according to the provisions of Procedure 1865.

The organization of operation must ensure the operating principles, avoiding sudden changes according to regulations. The organization must inform and notify the authorities and people in the downstream area about the operation and regulation of the lake.

Nhat Anh

Source: https://baochinhphu.vn/mua-lon-tren-dien-rong-tai-da-nang-cac-ho-thuy-dien-bat-dau-xa-nuoc-102251026101523343.htm