Binh Dien Hydropower Plant regulates to increase flood prevention capacity, welcoming heavy rain in the coming time

Compliance with operating procedures

The inter-reservoir system in the Huong River basin has just experienced continuous floods from late October to early November 2025. The proactive and coordinated regulation of the inter-reservoir system with scenarios has significantly contributed to reducing the depth of flooding in the downstream areas of the rivers.

According to the Irrigation Investment and Construction Management Board 5, from October 15 to 30, the Ta Trach reservoir basin (Phu Bai ward, Hue city) experienced 3 consecutive heavy rains. Then, from the night of November 2 to November 3, the Ta Trach reservoir basin had heavy rain, some places had very heavy rain. The total rainfall from November 2 to 3 at stations in the reservoir basin was generally from 94.8 - 722mm.

The extreme heavy rainfall from October 26 to 28 caused the water flow to reach over 6,900m3/s at times. The total water flow to Ta Trach Lake during the whole period was over 917 million m3, of which over 651 million m3 was regulated downstream, over 266 million m3 was retained, equivalent to the ability to reduce the flood peak by about 30%. Thanks to proactive and flexible operation, Ta Trach Lake has contributed to significantly reducing flooding in the city center and downstream of the Huong River. Currently, the lake is being regulated to gradually lower the water level to a low level, both ensuring the safety of the project and creating flood capacity for the upcoming heavy rains due to the circulation of storm No. 13.

Similarly, at Binh Dien hydroelectric reservoir on the Huong River basin, the regulation of this reservoir has cut 54% of the flood peak for downstream.

According to Binh Dien Hydropower Joint Stock Company, in the historic flood that appeared in the city starting from October 26 until now, with exceptionally large and concentrated rainfall in a short period of time in the basin. This is a flood with very large rainfall in the upstream in a short period of about 3 days with rainfall concentrated in the basin of the lakes exceeding 1,400mm, compared to the flood in 1999, which had a duration of rain lasting up to 6 days, evenly distributed in the plains, the rainfall in the mountainous areas was smaller than in the plains. Binh Dien Hydropower Joint Stock Company has correctly implemented the inter-lake and single-lake operating procedures of the plant to contribute to the work of cutting, reducing and slowing down floods for the downstream, contributing to ensuring absolute safety for works and equipment as well as maintaining stable power generation operations.

Increase flood capacity

At Ta Trach irrigation reservoir (Phu Bai ward, Hue city), recorded at 11:00 a.m. on November 4, the upstream water level reached 43.74 m, the inflow was more than 410 m3/s, the outflow was 1,094 m3/s, the reservoir is operating 4 spillways to regulate water. Currently, the inflow to the reservoir is smaller than the downstream flow. Explaining this, Mr. Nguyen Quy An, Deputy Head of Ta Trach reservoir management board, said that, implementing the telegrams of the Ministry of Agriculture and Environment, the City People's Committee, the reservoir management unit is operating to lower the reservoir water level to the flood-receiving water level to increase the ability to cut and reduce floods for the downstream in the coming time.

Mr. Nguyen Tam Phuong, Deputy General Director of Binh Dien Hydropower Joint Stock Company, said that the flood peak of the whole period appeared at 10:00 on October 27 at about 6,512m3/s (nearly equal to the flood peak flow with a frequency of 0.1%). At this time, the reservoir regulates 3,500m3/s, cutting 54% of the flood peak for the downstream. Currently, the water level of the reservoir is at +82.14m, the flow is up to 634m3/s, the flow regulated through the spillway and turbine is 1,251m3/s. The unit is implementing the direction of the National Civil Defense Steering Committee in Official Dispatch No. 24/CD-BCĐ-BTNMT dated November 1, 2025, in which priority is given to creating maximum flood prevention capacity for reservoirs and the City Civil Defense Command Committee, in order to gradually bring the reservoir water level back to the prescribed elevation in the inter-reservoir operation process to proactively respond to the upcoming rainstorm caused by the circulation of storm No. 13.

“With full preparation of disaster prevention and control plans, spare fuel supplies as well as adequate necessities for factory staff and workers on duty, and especially the proactive creation of maximum flood prevention capacity for downstream areas, Binh Dien hydropower reservoir has contributed to reducing flood peaks for the downstream area of ​​the Huong River,” Mr. Nguyen Tam Phuong added.

Currently, the flood drainage system in the downstream area has been improved, but is still not synchronized, the main drainage axes are silted, garbage, and duckweed obstruct the flow to the lagoon. In addition, the heavy rains in recent days have caused the water in the inland area to flow into the main river, while the high tide rises from 8 to 13 hours every day, combined with the influence of storm No. 13 offshore causing strong winds, rising water and silting of the river mouth, slowing down the ability to drain the flood.
Article and photos: HA NGUYEN

Source: https://huengaynay.vn/kinh-te/ho-dap-gop-phan-cat-giam-dinh-lu-cho-vung-ha-du-159640.html