In response to public opinion from the press and the proposal of the People's Committee of Quy Chau district about the historic flood that caused damage of over 177 billion VND, on October 13, 2023, the Department of Industry and Trade established an Inspection Team to inspect the implementation of the operation procedures of Chau Thang and Nhan Hac hydropower reservoirs. By October 31, 2023, the Inspection Team had Inspection Result Report No. 2484/SCT-BC.QLNL sent to the Provincial People's Committee. In the 11-page report, it is shown that the Team has inspected in detail and comprehensively the operation work; the implementation of notices and warnings on operation to ensure safety for the downstream area; the implementation of the regulations on coordination of reservoir operation... of each hydropower plant, from which conclusions, recommendations and proposals can be drawn.
Regarding Nhan Hac Hydropower Plant, the Inspection Team identified two areas of poor implementation, including: "The plant's forecasting work is not accurate, and it is still passive in forecasting water flow to the reservoir, so it has not been able to issue early warning notices to the downstream area"; "The coordination work in natural disaster prevention and control between the plant and the People's Committee of Quy Chau district has not been done well. The issuance of notices has not been closely connected (the plant's inbox has recorded the sending of notices on reservoir operation and regulation via Gmail email in compliance with the provisions of Point d, Clause 4, Article 7 of the Operation Procedure, but the People's Committee of Quy Chau district reported that it had not received them)".
However, according to the Inspection Team, the Nhan Hac Hydropower Reservoir has an operating procedure approved by the Provincial People's Committee. Accordingly, flood regulation operations (from the time the flood rises until it reaches its peak) must not increase the discharge flow downstream compared to the natural flow to the reservoir; on the other hand, the Nhan Hac Hydropower Reservoir has a small useful capacity (4.82 million m³), no flood prevention capacity and no flood cutting function. Therefore, based on the water level of the Nhan Hac Hydropower Reservoir during the flood discharge operation provided by the reservoir owner, the plant has operated in compliance with the operation of the flood discharge equipment according to the approved procedure.
Regarding the operation of raising the valve gate earlier than expected according to Notice No. 2709/2023/TB-NMNH sent to agencies and units at 01:56 (expected at 05:30, actual at 03:00 on September 27, 2023), the owner of the reservoir operates in an emergency situation (stipulated in Point b, Clause 16, Article 23) and performs the operation to ensure safety for the project according to the provisions of Clause 2, Article 14 of the Nhan Hac hydropower reservoir operation procedure. The total discharge flow through the plant (through the generator, through the gate and free spillway) from 3:00 a.m. on September 27, 2023 (the time the gate starts opening from the fully closed state) to 2:15 p.m. on September 27, 2023 (the time the spillway gate is completely closed) is not greater than the flow to the lake, so it does not increase flooding in the downstream area.
Regarding Chau Thang Hydropower Plant, the Inspection Team discovered that the monitoring equipment had a "problem" at a sensitive time. This content is specifically stated in the report as follows: "Due to the incident, automatic water level monitoring data was only available until 23:00 on September 26, 2023, then lost storage data until 01:30 on September 27, 2023, automatic monitoring data was restored and measured and stored at 02:00 on September 27, 2023, after this time no automatic measurement data was recorded. The plant calculated the monitoring data manually". Therefore, along with the assessment that "the plant's forecasting work is not accurate, and is still passive in forecasting water flow to the lake, so early warning notices have not been issued to the downstream area", the Inspection Team determined that Chau Thang Hydropower Plant: "Did not perform well the inspection, maintenance and repair of equipment serving the operation, leading to damage to automatic monitoring and surveillance equipment".
However, according to the Inspection Team, Chau Thang Hydropower Reservoir has an Operation Process approved by the Provincial People's Committee. It stipulates that flood regulation operations (from the time the flood rises until it reaches its peak) must not increase the discharge flow downstream compared to the natural flow to the reservoir; on the other hand, Chau Thang Hydropower Reservoir has a small useful capacity (4.217 million m³), no flood prevention capacity and no flood cutting function. Therefore, based on the water level of the reservoirs during the flood discharge operation provided by the reservoir owner, the plant has ensured compliance with the operation of the flood discharge equipment according to the approved process. At the same time, it is determined that: "The total discharge flow through the plant (through the generator, through the valve gate and free spillway) from 02:35 on September 27, 2023 (the time when the valve gate starts to open from the fully closed state) to 06:00 on October 5, 2023 (the time when the spillway gate is completely closed) is not greater than the flow to the lake, so it does not increase flooding in the downstream area".
Regarding Report No. 2484/SCT-BC.QLNL of the Inspection Team of the Department of Industry and Trade, Nghe An Newspaper reporters received some exchanges from officials at two levels of Quy Chau district. In general, the conclusion of the Inspection Team did not correctly assess the responsibility of the two hydropower plants Chau Thang and Nhan Hac. From the perspective of those who directly fought the floods with the people, they affirmed that heavy rain was the main cause. However, the flood discharge operation of the hydropower plant was too sudden, the discharge volume was very large while the flood discharge announcement was too late compared to the regulations, and at midnight and 1-2 am, so the officials and people were unable to react in time, had to abandon their belongings to save people, leading to many losses.
Officials at two levels of Quy Chau district are concerned: Firstly, the report of the Inspection Team stated that at the time of flood discharge, the monitoring equipment of Chau Thang Hydropower Plant had a "problem"; "could not record automatic measurement data", so are the data reported "by manual methods" of this unit reliable enough to conclude that "based on the water level of the reservoirs during the flood discharge operation provided by the reservoir owner, the plant operated in compliance with the operation of flood discharge equipment according to the approved process"?
Second, the two hydropower plants Chau Thang and Nhan Hac must strictly comply with the regulations of the Ca River inter-reservoir operation process (issued together with Decision No. 1605/QD-TTg, dated November 13, 2019 of the Prime Minister) and the single-reservoir operation process (issued by the Provincial People's Committee). However, the report shows that the Inspection Team mainly focused on inspecting according to the regulations of the single-reservoir operation process; why not pay attention to the regulations of the Ca River inter-reservoir operation process?
Regarding the incident of Quy Chau district suffering from the historic flood on September 26 and 27, Nghe An Newspaper reporters have researched and reported on the current situation. Therefore, they share the same concerns with the officials at both levels of Quy Chau district.
Please repeat the article "Have Chau Thang and Nhan Hac Hydropower Plants complied with Decision 1605/QD-TT-BCT of the Prime Minister?” in the issue published on October 19. Here, a number of regulations of the inter-reservoir operation process of the Ca River basin were specifically cited. Such as Clause 2, Article 5 (principles of reservoirs to reduce floods for downstream areas); Clauses 2, 3, 5 of Article 32 (reservoir owners' responsibilities) and Articles 36 (monitoring regime during flood season), 37 (responsibility for reporting and providing information during flood season). These regulations require hydropower plants listed in the inter-reservoir operation process of the Ca River basin, including the two hydropower plants Chau Thang and Nhan Hac, to strictly comply.
The reason why it is necessary to specifically quote is because the principle of flood reduction reservoirs for downstream is: "Flood reduction operations for downstream must ensure that they do not cause sudden changes in flow or abnormalities that directly threaten the lives and property of people in the riverside areas downstream of reservoirs; in case of damage, compensation must be paid according to the provisions of law". Because forecasting, warning, reporting, providing information... are extremely important contents, related to the safety of people in downstream areas during the flood season.
And because in Quy Chau district, right at the foot of Chau Thang hydropower dam are rivers, streams and villages of people in Chau Tien and Chau Thang communes. Once the rain monitoring and measuring equipment system is incomplete or damaged; forecasting and warning information is not taken into account; reporting and providing information is slow and incomplete... or even as the Inspection Team assessed, "the forecasting work of the plant is not accurate, and is still passive in forecasting water flow to the lake, so early warning announcements have not been made", then the disaster for the people of Quy Chau will recur!