At the meeting, Minister Chu Ngoc Anh highly appreciated Vietnam Electricity (EVN) and its member units for managing 5 hydropower plants on the Da River cascade (Lai Chau, Son La, Hoa Binh, Huoi Quang and Ban Chat), successfully completing the operation and management of these plants, regulating the reservoirs in 2019 and early 2020.
Through monitoring and measuring findings, the condition of these power plants up to now is safe and stable. The companies have carried out overall inspections, safety assessment of dams, reservoirs, rehabilitated and strengthened construction structures and equipment; taken proactive measures to prevent, control and promptly handle damages in order to ensure the safety of dams and reservoirs. The power plants are in good condition to participate in flood control and water storage in 2020.
Minister Chu Ngoc Anh delivered a conclusion speech at the meeting
Minister Chu Ngoc Anh suggested that those managing the 5 above hydropower plants should continue to focus on making detailed plans for dam safety inspection; developing plans to survey and assess the quality status of plants; paying attention to the maintenance of mechanical equipment and control systems in order to promptly replace technically satisfactory equipment; synchronously deploying the sediment measurement of reservoirs to facilitate the assessment of sediments throughout the system and impacts on sediment regime in the downstream; studying and applying scientific and technological advances to the inspection, dam monitoring, hydro-meteorological observation, calculation of flood processes, etc. to operate hydropower plants efficiently and safely, not affecting downstream projects and areas.
Reported at the meeting, Mr. Ngo Son Hai – Vice President of EVN said: The hydrological situation in the Da River catchment in 2019 was unpredictable and unfavorable for hydropower plants on the Da River cascade. The total amount of water inflow to the reservoirs in 2019 was seriously deprived, only about 55 - 60% of the average level over many years.
In the flood season in 2019, the amount of water inflow did not meet requirements for plant operation, therefore the water levels of reservoirs were always in low levels. At the end of the flood season, the amount of water inflow to the reservoirs had not improved. The drought situation, lack of water prolonged, especially Hoa Binh reservoir had to meet requirements for both water storage for production in the Winter - Spring crop in 2019 - 2020, electricity generation, and maintaining water flow to meet water needs of downstream areas.
EVN’s Vice President Ngo Son Hai reported on the operation of 5 hydropower plants on the Da River cascade managed by EVN
The hydropower companies under the Group on the Da River hydropower cascade system have been operating their reservoirs in compliance with the inter-reservoir operation procedure in the Red River catchment which was issued as attached to Decision No. 740/QD-TTg dated June 17, 2019 of the Prime Minister (Procedure 740).
In 2019, floods hardly occurred in the catchment, which affected the power generation output of the plants in comparison with the average for many years and their designed targets. The total electricity production of all 5 above power plants in 2019 was 20,323 billion kWh, down 10.6 billion kWh compared to 2018; In the first 5 months of 2020, it was 4.39 billion kWh, down 4.58 billion kWh compared to the same period in 2019.
To ensure safe, stable and economical operation of the power plants, Mr. Ngo Son Hai proposed that the Council should continue to recommend the General Department of Meteorology and Hydrology to improve the quality of rain forecast in small areas, improve the ability to detect early floods and identify the time of peak floods.
In addition, the Council is recommended to advise the Institute of Geophysics to strengthen their coordination with EVN to be able to forecast and alert earthquakes in the basin for dam owners so that they can make up their prevention plans; advising the General Department of Disaster Prevention to count on assessments of the National Center for Hydro-meteorological Forecasting to operate reservoirs reasonably, make the most of water resources and if deeming that late floods are not happening, they should proactively consider allowing reservoirs to store water earlier than that stipulated in the Procedure.
Recommendations are made that the Council should advise the Ministry of Natural Resources and Environment to revise the inter-reservoir operation procedure on the Red River catchment, gradually accessing real-time approach; studying and proposing revisions of Procedure 740 to well ensure the safe operation of dams, reservoirs and efficiently exploit water resources.
It is also recommended that the Council should review and comment on the water intake of Da River Water Plant so that it does not depend on the operation of Hoa Binh Hydropower Plant.
The People's Committees of Lai Chau, Dien Bien, Son La and Hoa Binh provinces are recommended to take measures to communicate with local people about forest planting and development, gradually restricting and towards prohibiting the use of herbicides which destroy the environment, increase soil erosion, increase sedimentation and suspended substances, and consequently affect water quality of reservoirs.