With successive extreme floods battering central Vietnam, the operation of water reservoirs, especially hydropower dams, has drawn growing concern. At the recent forum “Digital transformation and technology application in dam operation and safety,” experts raised urgent issues, revealing an overwhelmed and outdated reservoir management system.

Reservoirs lack data, rely on manual alerts

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As of 6:00 a.m. on November 24, heavy flooding continued across central and Central Highlands Vietnam, submerging numerous areas and disrupting traffic. Photo: Xuan Ngoc

According to the Department of Hydraulic Works Construction Management under the Ministry of Agriculture and Environment, reservoirs serve not only irrigation purposes but also act as critical "shields" protecting local populations, securing water sources, and supporting socio-economic development.

However, many of these facilities were built decades ago. The supporting systems for data collection and forecasting remain fragmented and insufficient, leading to reactive and inefficient operations.

Phan Tien An, Head of the Dam Safety Division, noted that recent extreme floods have placed immense pressure on the management and operation of reservoirs. Despite a growing legal framework, major vulnerabilities persist.

Currently, only 30% of reservoirs have emergency response plans, 51% have protection strategies, just 9% have undergone safety inspections, 31% have operational procedures in place, 19% are equipped with meteorological monitoring tools, and a mere 11% have clearly marked safety perimeters.

While most reservoirs have been logged into national management systems, only about 900 of them have comprehensive technical specifications. Many others only list basic information such as name, capacity, and location. Meanwhile, 592 weirs have yet to be included in technical data systems.

Flood warnings remain rudimentary in many cases, relying on phone calls or official memos. This creates dangerous delays during fast-moving and unpredictable storm conditions.

As of the 2025 flood season, only 19% of reservoirs have specialized monitoring equipment, just 9% are safety-certified, and only 30% have emergency plans. Nationwide, only 411 reservoirs have flood inundation maps for downstream areas - vital data for early warning systems.

Outdated procedures lead to reactive management

Nguyen Tung Phong, Director of the Department of Hydraulic Works Construction Management, acknowledged that recent extreme weather events have exposed significant operational weaknesses, indicating that the system is facing unprecedented challenges.

Many single and interconnected reservoir operation procedures are still based on outdated historical data, failing to reflect conditions from the last two to three years. In reality, rainfall events can bring water volumes four to six times the monthly average, breaking historic records.

Some reservoirs prematurely lower water levels due to uncertain forecasts, undermining water storage and flood mitigation goals. Reservoirs with uncontrolled spillways and no regulating gates are especially vulnerable during back-to-back storm events.

Phong emphasized the need for a shift to risk-based, watershed-wide water governance. Instead of operating each reservoir in isolation, authorities must adopt a multi-objective management strategy - one that balances flood control, infrastructure safety, water supply, and environmental protection.

He also highlighted the crucial role of hydropower dams. While Vietnam’s more than 7,000 irrigation reservoirs hold about 15.5 billion cubic meters of water, individual hydropower dams often exceed this volume. If these larger dams played a more integrated role in flood management, downstream safety could greatly improve - especially during record-breaking storms.

Call for coordination and digital transformation

Phong stressed the need for closer coordination between irrigation and hydropower sectors and called for increased application of modern technologies. Enhancing safety and supporting development amid climate change will require smarter systems.

Key proposals include strengthening forecasting and early warning capabilities, integrating and utilizing platforms such as Vrain, corporate forecasting data, rainfall–runoff models, and hydraulic simulations. The goal is to move from uncertain “forecasting” to reliable “notification,” enabling operators to proactively lower water levels while ensuring safety.

The Ministry of Agriculture and Environment plans to propose amendments to the Law on Water Resources between 2027 and 2028. It will also review relevant decrees based on a comprehensive assessment of recent extreme weather patterns.

Experts have pointed out that some hydropower dams operate at intermediate water levels and then abruptly discharge large volumes during storms. This reactive approach often results in sudden downstream flooding, leaving communities unprepared and exposed.

Vu Diep