Coping with typhoon No. 9: How were EVN’s hydropower reservoirs operated to control and prevent floods?

On the Vu Gia-Thu Bon river basin, EVN hydropower plants had been operated proactively to discharge water before the typhoon landed, bringing water levels in the reservoirs to pre-flood levels as prescribed in the regulations of the inter-reservoir operation procedure and as required by the Command for Natural Disaster Prevention, Search and Rescue in provinces, to contribute to effectively controlling and reducing floods in typhoon No. 9.

The EVN’s reservoirs in the Vu Gia-Thu Bon region most affected by typhoon No. 9 included A Vuong, Song Bung 2, Song Bung 4, Song Tranh 2 reservoirs, the National Load Dispatch Center (A0) said. Flood peaks occurred in reservoirs in the evening on 28 October 2020. Just in two days, the total water inflow to the above reservoirs reached about 444 million m3; of which about 75 million m3 to A Vuong reservoir, 26 million m3 to Song Bung 2 reservoir, 105 million m3 to Song Bung 4 reservoir, and about 239 million m3 to Song Tranh 2 reservoir.

With such a large amount of water inflow in just a short time, without good preparation in advance, it would be very dangerous for facilities in downstream areas. In anticipation of the situation, EVN instructed reservoir owners to lower water levels of the reservoirs, bringing the water levels to pre-flood levels in accordance with the regulations of the inter-reservoir operation procedure and as required by the Command for Natural Disaster Prevention, Search and Rescue at provinces.

According to A0, with the proactiveness in flood regulation, on 28-29 October 2020, EVN’s reservoirs on Vu Gia-Thu Bon river basin helped to alleviate floods in downstream areas, retaining about 216 million m3 of water in the reservoirs, playing a great part in preventing storm and controlling flood in downstream areas.

At the time of flood reduction for downstream, water discharge from the reservoirs to downstream areas compared with the water inflow were as follows: Song Bung 2 (40%), Song Bung 4 (4%), A Vuong (7.8%), Song Tranh 2 (31%), showing that the reservoirs had cut down from 60% to 94% of the peaks of floods traveling to the reservoirs.

Along with the regulation of the reservoirs to contribute to flood reduction and control in downstream areas, EVN and its units had worked hard day and night in order to resume power supply to affected customers as quickly as possible.


  • 30/10/2020 10:20
  • evn.com.vn
  • 202