Irrigation works lose function due to degradation

Series of degraded irrigation works

Quang Tri Irrigation Works Management and Exploitation Company Limited is assigned to manage and operate many key irrigation works in the area. These works include 2 dams with a total designed flow of over 33 m3/s; 17 reservoirs with a capacity of over 185 million m3 of water; 29 electric pumping stations; 10 saltwater prevention dams; 1 flood diversion work...

The system of dams and irrigation works in Quang Tri province is of great significance in the development of local agriculture. Photo: Vo Dung.

The irrigation works managed by the company are responsible for providing irrigation water for more than 32,000 hectares of agricultural land in 8/10 districts, towns and cities (over 64% of the total agricultural land area of ​​the province); preventing salinity and keeping fresh water for 14,300 hectares/year. In addition, these key works are also responsible for providing water for industrial production, aquaculture and serving other people's lives and economies.

In recent years, many large dam and lake projects such as Nam Thach Han dam, Hieu river saltwater prevention dam, Da Mai, Tan Kim, Ha Thuong, Truc Kinh, Kinh Mon, La Nga, Trieu Thuong 1, Trieu Thuong 2 reservoirs have been invested in and upgraded. Main canals to level 1 canals have mostly been solidified.

The upgraded and repaired irrigation systems have promoted irrigation efficiency, served agricultural production, contributed to increasing food output, ensured economic and social stability and development, and ensured construction safety in natural disaster prevention.

However, there are still some medium and small dams that have not been invested in for repair, upgrading, and safety assurance. In particular, Phu Dung and Nghia Hy reservoirs were invested in and built before 1990, and the projects were designed according to old design standards, which do not ensure flood prevention in the current extreme rainy and flood weather conditions.

Some canals and structures located in low-lying areas, under the impact of flood flows, have caused landslides and silting of the canal bed. The total length of damaged canals is more than 2,000m. Of which, the total length of the canal slope is 450m, the total length of the canal bed is silted up with nearly 1,600m, and the 76m canal wall has collapsed. Some items of the Vinh Phuoc and Chau Thi saltwater prevention works have been damaged...

Many irrigation works have degraded and need to be upgraded, repaired and modernized. Photo: Quoc Toan.

Every year, the cost of overcoming the consequences of storms and floods as well as the regular maintenance and repair costs have not met the actual needs, so many construction items are damaged and degraded. Some contents of dam and reservoir safety management such as dam safety inspection; installation of specialized hydrometeorological equipment; development of response plans in emergency situations; installation of monitoring, operating systems, and safety warning information equipment for dams and downstream areas have not been allocated funds to ensure implementation according to plan. Therefore, there is still a potential risk of unsafe construction during the rainy and flood season. Irrigation efficiency has not been as expected.

Upgrading irrigation system is urgent requirement

According to statistics, in Quang Tri, in 2024, floods caused nearly 7.9 km of level IV or lower dykes, dikes, embankments; nearly 3 km of embankments; more than 20 canals; 32 sluices; 4 irrigation dams and many other irrigation works to be eroded, damaged, and silted up. The total damage to irrigation works was nearly 100 billion VND. After the floods ended, from many sources of capital, Quang Tri focused on overcoming and temporarily repairing some weak points to get water for production.

In addition, climate change and annual storms and floods with strong and continuous intensity have greatly affected irrigation infrastructure. Many irrigation works built long ago have degraded; previous designs focused mainly on small-scale agricultural production, serving rice, so it is difficult to change the function to meet large-scale production, serving multiple purposes.

The efficiency of water use for agriculture is not high, and there is still loss due to the inadequate canal system. Production arrangement and management are not reasonable. Increased water exploitation activities, sand and gravel exploitation activities on rivers are the main causes of bank erosion, lowering of river beds, depletion of water resources, degradation of water environment...

Negative impacts from climate change and small-scale investment have caused many projects to no longer function to their full potential. Photo: Vo Dung.

A picture with many dark colors of irrigation works in Quang Tri makes many people worried. The function and efficiency in serving production, daily life and economic development also raises many questions.

Quang Tri has identified sustainable agricultural and rural development, increasing added value, efficiency and competitiveness, moving towards building a smart, modern agriculture that adapts to climate change. The locality aims to stabilize grain output at 25-26 thousand tons/year; by 2025, proactive irrigation will be ensured for over 90% of the two-crop rice growing area, and by 2030, 100% of the area will be achieved.

The above objectives have a great impact on the operational efficiency of irrigation works. The irrigation system needs to be upgraded and modernized to maximize its design capacity; ensure proactive irrigation of 2-crop rice fields, color areas and industrial crops from 5,500-6,000 ha, supply water for aquaculture of 2,500 ha; prevent salinity and retain fresh water of 15,500 ha; enhance flood drainage capacity for residential areas; drain water for 21,500 ha of agricultural land in the coming years.

To achieve the above goal, investing in the synchronous development of agricultural infrastructure to meet the requirements of large-scale, concentrated commodity production is an urgent task.

Upgrading and modernizing the irrigation system is an urgent requirement. Photo: Quoc Toan.

Mr. Le Quang Lam, Head of the Quang Tri Irrigation Sub-Department, said that ensuring water security; improving the efficiency of management, operation, and safety of the dam system are key factors that need to be given due attention. Research, development, application of science and technology, and digital transformation in ensuring water security and dam safety to proactively prevent, combat, and minimize adverse impacts caused by natural disasters related to irrigation infrastructure also need to be given more attention.

Besides, the issue of strengthening environmental protection, protecting aquatic resources, preventing pollution, degradation, and depletion of water resources... to promote sustainable development of agricultural production in the province also needs to be focused on.

“Quang Tri has mobilized capital sources to upgrade and repair the irrigation system to ensure safety; prioritized maintenance, repair of minor periodic damages to serve production. In 2025, the locality will focus resources from the central, local, organizations and individuals to invest in infrastructure of irrigation works,” said Mr. Le Quang Lam, Head of the Quang Tri Irrigation Sub-Department.

Source: https://nongnghiep.vn/cong-trinh-thuy-loi-giam-cong-nang-do-xuong-cap-d744071.html