HANOI: The Ministry of Agriculture and Environment has approved a proposal to build three regulating dams on the Red, Duong and Da rivers, designed to manage seasonal water flows more reliably and strengthen resilience to climate change.
The approval clears the way for further study and design work on the project, which has been put forward by the People's Committee of Hanoi.
Three dams would be built under the plan, namely the Xuan Quan Dam on the Red River, the Long Tuu Dam on the Duong and a third structure on either the Da or Red River.
Officials say the dams would serve several purposes at once: guaranteeing water supplies for farming and household use, improving water quality in irrigation networks and supporting river-based transport and tourism.
They are also expected to help manage water flows from the Red River into the Duong and work in tandem with upstream reservoirs to hold back saltwater intrusion in the Red River Thai Binh Delta downstream.
The dam planned for the Da carries a more specific mandate. It is expected to ensure enough water flows through the Luong Phu Sluice Gate to feed the Tich and Day Rivers, while supporting power generation, water transport and daily use – all without disrupting the Da's capacity to drain floodwater.
In approving the concept, the ministry instructed the city government to pursue the project in a way that is economically sound and technically rigorous.
Planners must ensure the dams do not compromise flood discharge capacity or dike safety, do not heighten the risk of landslides or other natural hazards, and do not lower water levels downstream in ways that would hamper nearby irrigation and drainage systems.
They are also instructed to prevent sediment from accumulating upstream of the structures, which could damage the local ecosystem.
For the dam on the Da in particular, the ministry set an uncompromising red line: the project must not, under any circumstances, affect the minimum downstream water level required by the design specifications of the Hoa Binh Hydropower Plant.
Beyond those safeguards, the ministry called for a full assessment of how the dams would affect river morphology, navigation, fish migration, water quality and sediment transport.
The ministry also instructed that the project conform to Conclusion 467, a document issued in May after discussion between ministry and Hanoi officials on a separate initiative, the Red River Landscape Boulevard. - Vietnam News/ANN
