In the early morning of September 16, in Hoa Binh province, there were thunderstorms and prolonged heavy rain, especially in Da Bac district and Hoa Binh city (localities in the Hoa Binh Hydropower Reservoir area).
Rainfall measured in Hoa Binh city was 68.4mm, of which the highest in Doc Lap commune was 86.8mm.
According to information from Hoa Binh Hydropower Plant, at 11:00 a.m. on September 16, the upstream water level of the hydropower reservoir was at 115.41m; downstream 11.64m; Water flow into the reservoir was 2,436m3/s; Water flow out was 2,090m3/s.
On the same day, at Hoa Binh Hydropower Plant, according to Lao Dong Newspaper's reporter, all bottom spillways were closed.
Earlier, on the morning of September 15, speaking with Lao Dong Newspaper, Mr. Pham Van Vuong - Director of Hoa Binh Hydropower Company - informed that the lake water level is rising, currently 115.02m upstream (nearly 2m below normal water level), 11.27m downstream; inflow is 3,416m3/s; outflow is 1,714m3/s.
According to Mr. Vuong, the unit is closing all bottom spillways and reducing power generation capacity to ensure downstream safety. The closing and opening of the bottom spillways will depend on hydrological developments, the amount of water flowing in, and the direction of the National Steering Committee for Natural Disaster Prevention and Control.
On September 11, the upstream water level of Hoa Binh Lake was at 111.65m (dead water level was 80m), the inflow to the lake was 1,947 m3/s, the discharge to the downstream was 3,910 m3/s. Implementing the telegram of the Minister of Agriculture and Rural Development, Hoa Binh Hydropower Company closed the remaining bottom discharge gate at 9:00 a.m. the same day.
