Ensuring safety for the downstream area of Dau Tieng Lake in the face of complex weather developments

Photo caption — Dau Tieng Lake is located in Tay Ninh, Ho Chi Minh City and Dong Nai, with a basin area of over 270 km2, a capacity of 1.58 billion m3 of water, and is a particularly important project related to national security.

Prepare thoroughly to prevent natural disasters

Dau Tieng Lake is located in the upper reaches of the Saigon River, designed to serve multi-purpose exploitation management, a special-class reservoir with a designed capacity of 1.58 billion m3 of water. The irrigation and drainage canal system is a level I and II project, with a total length of about 150 km and more than 300 project items.

According to Mr. Tran Quang Hung, General Director of the Southern Irrigation Exploitation One Member Limited Liability Company, the lake water level at 7:00 a.m. on November 26, 2025 was at 23.83 m, 0.02 m higher than the average of many years and 0.57 m lower than the highest water level before the flood according to the process, the lake water is rising by an average of 1-2 cm/day. Since the beginning of the year, the company has discharged water through the spillway to maintain the flow and organized monitoring of rainfall, water level, flow to the lake and through the water intakes at the head of the canal. The total average rainfall in the basin from the beginning of the year to now is 2,043.79 mm, higher than the same period in 2024 and compared to the average of many years.

Currently, the unit is discharging water through the spillway for the 8th time in 2025 from November 25 to 7:00 a.m. on December 2, 2025, with a flexible discharge flow from 36-200 m3/s.

According to Mr. Tran Quang Hung, before releasing water, the company sends notices to relevant agencies, units and localities according to the inter-reservoir operation process. The flow and discharge time are adjusted in accordance with weather, tide and water level developments to ensure safety for the project and downstream. During the flood discharge periods, company staff coordinate with the Reservoir Police Station and Dau Tieng Commune People's Committee to check the current status of the canal and Saigon River.

Through inspection, currently, on the canal section after the spillway, there are a number of food and beverage businesses that have built structures that encroach directly onto the canal bed. When the reservoir is discharging 150-200 m3/s, these encroached structures have been flooded. Similarly, on the Cung River section in Nui Dat Hamlet, Dau Tieng Commune, there are also cases of housing construction right up to the riverbank. All these encroachment activities are narrowing the flood drainage, causing stagnation and flooding, affecting production activities, threatening people's lives and property.

The company has requested the locality to review and upgrade the dike system and tide-prevention sluices to ensure flood drainage when the reservoir discharges large volumes of water. At the same time, it has also encouraged people to arrange crops and livestock appropriately, proactively harvest, and limit fishing during periods when the reservoir discharges large volumes of water or when heavy rains or storms are forecast to ensure human life and property.

To proactively respond to natural disasters, the company has strengthened the Disaster Prevention Technical Board and the direct rescue force. Electrical, mechanical equipment, and valves are inspected and tested before the flood season to ensure safety. Materials and machinery are reviewed and prepared for additional supplies. The maintenance of 36 basic irrigation infrastructure items has been completed, costing 46,477 billion VND, achieving 90% of the plan.

The Dau Tieng irrigation system repair and upgrade project (phase 2) is being completed, including reinforcing the main dam, auxiliary dam and replacing the spillway gate, ensuring the safety of the project and stable water supply for the provinces. The project volume has reached over 99% and is expected to be completed in 2025. The company also plans to invest in upgrading the period 2026-2030.

The company strongly applies technology in administrative management, human resources, accounting, construction operations, environmental monitoring and water quality, automatic spillway operation via SCADA system and development of online information portals. In 2025, the company will hire consultants to review, evaluate the current status and propose to complete the Dau Tieng - Phuoc Hoa monitoring system. From 2026, the company will invest in installing automatic monitoring and applying technology to operational management.

Strengthening coordination with localities

Mr. Nguyen Viet Anh, Chairman of the Board of Members of the Southern Irrigation Exploitation One Member Limited Liability Company, said that the unit has developed an emergency response plan at Dau Tieng Lake. The downstream flood map has been approved by the Ministry of Agriculture and Environment and handed over to four localities: Tay Ninh, Binh Duong (old), Long An (old) and Ho Chi Minh City to develop a response plan. The company will continue to advise on adjusting place names and scope to suit the local government management model.

Mr. Nguyen Viet Anh suggested that localities pay attention to upgrading the embankments soon, especially the low-lying areas from the spillway to Thu Dau Mot (in Ho Chi Minh City). The current release of water from the reservoir is to prevent flooding and is announced early so that localities can proactively prepare, basically ensuring the safety of the downstream area. He also emphasized the need to increase interaction via chat groups, ensuring that information from management agencies to people is timely.

Mr. Dang Thanh Lam, Deputy Director of the Southern Institute of Water Resources Planning, said that in the past time, he had fully prepared for the management and operation of the reservoir and built a plan to respond to natural disasters. However, natural disasters, even if warned in advance, can still cause damage, especially when the southern region has not had a major incident for many years, leading to a subjective mentality. Therefore, reservoir operations need to be carefully reviewed to ensure the proper function of each project.

Mr. Lam emphasized that the plans at the grassroots level, from calculation, forecasting, flood mapping to updating natural disaster information and operating procedures, must be completed and promptly transferred to localities. This is an important factor in assessing the risks of flood areas and irrigation infrastructure. When response scenarios are well prepared, the handling will be proactive; on the contrary, subjective psychology about infrastructure and human resources can easily cause damage.

Regarding the flood map, Mr. Lam said that after completion, it needs to be fully handed over to the locality, especially the commune and hamlet levels, for propaganda. Grassroots staff must be instructed to clearly understand the flood situation in each area, the risk of damage and the evacuation plan. This is a specialized technical field, so it needs to be communicated thoroughly. For lakes that have participated in construction or have been consulted, the Institute has a good understanding of the expertise; for lakes that have not been approached, the Institute hopes to be provided with information for research. Through its advisory role to the Ministry and the provinces, the Institute will coordinate to communicate information that is easy to understand and most convenient for users.

Source: https://baotintuc.vn/xa-hoi/dam-bao-an-toan-cho-vung-ha-du-ho-dau-tieng-truoc-dien-bien-phuc-tap-cua-thoi-tiet-20251127181815093.htm