A professor proposed building a dam on which river so that polluted rivers like To Lich will flow naturally?

Prof. Dr. Dao Xuan Hoc, Chairman of the Vietnam Irrigation Association, said that the construction of two dams, Xuan Quan (Red River) and Long Tuu (Duong River), will create great convenience in taking water for polluted rivers such as Nhue River, Tich River, Day River... and riverside irrigation systems without affecting flood drainage capacity.

This proposal was made by Professor Dao Xuan Hoc at the working session of Deputy Prime Minister Tran Hong Ha on the Irrigation Planning of the Red River-Thai Binh River Basin and the Mekong River Basin for the period 2022-2030, with a vision to 2050, on the afternoon of March 24.

The Red River-Thai Binh River basin has an area of 88,860 km2, belonging to 25 provinces and cities, with a population of about 34 million people.

In the Red River-Thai Binh River basin, there are about 2,260 irrigation works, supplying water for 860,000 hectares of cultivated land, 151,000 hectares of aquaculture, 870 million m3 of industrial water, and draining water for 1.37 million hectares.

The reservoir system participates in flood prevention and control with an area of about 8.45 billion m3. The 2,108 km long dike system and 744 km of embankment protect more than 18 million people, 1 million hectares of agricultural land and socio-economic infrastructure.

Three issues facing the Red River-Thai Binh River basin are: Climate change, unusual and extreme natural disasters; dependence on border water sources (accounting for about 40%); pressure on socio-economic development.

Meanwhile, the small-scale irrigation system, old design, old technology, has not fully calculated the requirements to serve multiple purposes.

Deputy Prime Minister Tran Hong Ha chaired a meeting on the Irrigation Planning of the Red River-Thai Binh River Basin and the Mekong River Basin for the 2022-2030 period, with a vision to 2050, on the afternoon of March 24.

According to the report of the Institute of Water Resources Planning (the planning consultancy unit), the Red River-Thai Binh River Basin Water Resources Planning ensures consistency and synchronization with plans on natural disaster prevention and control, irrigation, water resources, and localities; synchronization between the development of irrigation infrastructure and the development of infrastructure in other sectors, inheriting the irrigation system that has been invested and built.

Irrigation works serve multiple purposes, have a long-term vision, aim to exploit and use water resources effectively, meet the requirements of socio-economic development, ensure water security, protect the water environment; contribute to preventing and combating natural disasters caused by water, protect the environment and ecology. Planning in an "open" direction to be able to flexibly adjust and supplement according to the requirements of socio-economic development, climate change, and rising sea levels.

On the mainstream, the consulting unit proposed solutions to regulate upstream reservoirs, build new dams, and control saline intrusion at river mouths.

Proposed location for dam construction on the Red River basin through Hanoi - Photo: Vietnam Institute of Water Resources.

In irrigation areas (midlands, mountainous areas, Red River Delta), reservoirs, dams, pumping stations, water transfer routes, drainage culverts, etc. will be upgraded, repaired, and newly built to serve irrigation, water supply, drainage, and sewerage.

Along with engineering solutions are non-engineering solutions such as advanced irrigation, water saving, crop restructuring, technology application, digital transformation in planning, construction, management, exploitation of irrigation works, and water resource protection.

Total land use demand to implement the Plan is about 6,700 hectares, capital is about 105 trillion VND.

The projects and works proposed in the Plan are built and calculated based on different scenarios of socio-economic development, climate change, and sea level rise.

Prof. Dr. Dao Xuan Hoc, Chairman of the Vietnam Irrigation Association, said that the construction of two dams, Xuan Quan (Red River) and Long Tuu (Duong River), will create great convenience in taking water for the Nhue, Tich, and Day rivers... and riverside irrigation systems without affecting flood drainage capacity, so the sooner it is done, the better.

Regarding the construction of two dams, Xuan Quan (Red River) and Long Tuu (Duong River), Deputy Minister of Agriculture and Environment Nguyen Hoang Hiep said that rivers across the country are experiencing a phenomenon of sinking bottoms. The most serious is the Red River, followed by rivers in the South Central Coast, North Central Coast and the Mekong Delta.

"The Red River drops an average of one centimeter each year, and in 10 years, the water level drops a meter. The riverbed is getting lower and lower, and all the structures connected to it are now exposed and cannot get water," said Mr. Hiep, citing that 10 years ago, hydropower plants only needed to release about 3 billion cubic meters of water to serve the winter-spring season. But three years ago, even if the amount of water was released twice as much, irrigation water still could not be obtained because the riverbed was lowered and the pumping system was located at a high position.

To provide water for the 2024 winter-spring crop, the irrigation sector is forced to rebuild almost all pumping stations and extend pipes to proactively take water from the Red River. "If we wait for the release, we still cannot get 6 or 7 billion m3 of water," said Deputy Minister Hiep, adding that the dry situation also causes pollution downstream.

Mr. Hiep stated two reasons for the lowering of the Red River bed: upstream construction of many irrigation works and reservoirs, which limits alluvium, and uncontrolled sand mining.

Deputy Minister of Agriculture and Environment Nguyen Hoang Hiep.

Deputy Minister Hiep said it is necessary to soon study raising the riverbed or raising the water level. The first solution is to build dams, but it will be difficult to avoid unwanted impacts such as changing the flow, leading to a series of environmental problems, including water quality and microflora.

However, Mr. Hiep affirmed that "it is impossible not to build" a dam on the Red River to ensure the environment for the entire Hanoi and surrounding areas. When the Red River rises, it will help the Nhue, Day and even To Lich rivers to have natural flows as before.

"Hanoi has planned a city on both sides of the river. But we cannot have a river without seeing water. We have to raise the water level to make this happen," said Mr. Hiep, adding that the Ministry has assigned the Institute of Water Resources to study a state-level project to build a dam on the river and accept it in 2020.

According to Deputy Prime Minister Tran Hong Ha, irrigation works are not just dykes, reservoirs, pumping stations, etc. standing alone, but need to be viewed broadly with the ability to connect urban areas and urban works.

The consulting unit must use simulation models for each period of extreme weather in the Red River-Thai Binh River basin to explain and have a synchronous and comprehensive solution, applying new and modern technology to be able to change the planning of previous flood drainage areas, thereby impacting the local socio-economic development thinking.

"The new thinking in planning the irrigation system to manage water resources is to connect, close, follow nature, with human participation in regulation to bring about economic efficiency in many aspects such as water supply, waterway transport, tourism, drought prevention, saltwater prevention, flood drainage...", said the Deputy Prime Minister.

Comment (0)