Need to upgrade and repair degraded irrigation works

QTO - Currently, in the northern localities of Quang Tri province, many dams, irrigation reservoirs and important canal systems are seriously degraded, eroded and damaged for a long time. This not only greatly affects the efficiency of water supply for production and daily life but also poses potential safety risks, especially when the rainy and stormy season arrives.

The deterioration of dams is mainly concentrated in works managed by Quang Binh Irrigation Works Exploitation Company Limited.

Mr. Nguyen Huu Sang, Deputy Director of the company, said: The company is assigned to manage 35 reservoirs, 2 dams, Rao Nan irrigation system, My Trung saltwater prevention and freshwater retention sluice, over 289km of various canals and 12.23km of dykes... serving irrigation for 31,085ha of 2-crop rice, supplying water for domestic water plants over 12 million m3/year. Most of the works were built over 30-40 years ago and have now been seriously damaged due to the impact of weather and natural disasters, especially some key items of the works and the main water channel system.

The South Main Canal, Vuc Tron Lake, section passing through Hoa Trach commune has been eroded, greatly affecting the water supply capacity, safety of the canal and traffic routes - Photo: BT

Through inspections by functional units and companies, it was found that some key items of reservoirs such as Trung Thuan, Mu U, Be, Ba Nuong, Khe Ngang, Phu Hoa, Tien Lang, Rao Da were damaged. Some earth dams appeared to seep, causing instability to the works. These works were inspected by the Provincial People's Committee and included in the list of priority works for repair, to ensure dam safety in Document No. 2386/QD-UBND, dated December 12, 2024.

Many main canals of the projects, such as: Da Mai, Vuc Tron, Be, Phu Vinh, Tien Lang, Phu Hoa, Cam Ly, Vuc Noi... have been seriously degraded. The junction between the wall and the bottom of the canal is broken; many sections of the canal have collapsed, causing landslides, not ensuring the efficiency of water conduction of the project. In particular, this situation also threatens the safety of production land, residential buildings of the people as well as some traffic routes.

Head of Bo Trach Irrigation Branch Nguyen Viet Sy said that the main canal system of Da Mai dam is 17.5km long, passing through Nam Trach and Hoan Lao communes, and was invested and built in 1986, serving irrigation for over 1,000 hectares of double-crop rice. After a long period of exploitation, the project has been seriously damaged. Although in 2022, the Provincial People's Committee has arranged public investment from the provincial budget to repair and upgrade this canal. However, due to limited funding, only some weak and local sections have been repaired and upgraded.

Currently, the main canal of Da Mai dam from Km0 to Km1+100 (1,100m long) and from Km2+320 to Km6+650 (5,330m long) is seriously degraded. The junction between the wall and the bottom of the canal is broken, many sections of the canal have collapsed, causing landslides. Leaking water and water loss not only reduce irrigation efficiency but also cause land erosion for households living along both sides of the canal.

A section of the main canal system of the Da Mai dam collapsed and caused landslides in the production land of people in Hoan Lao commune - Photo: BT

Ms. Nguyen Thi An, Bang village, Hoan Lao commune said that her house is next to a section of Da Mai canal that has been eroded, so she is very worried and hopes that the authorities will take timely remedial measures so that her family can feel secure in their production and living.

In the same situation, the Chinh Nam canal, Vuc Tron lake, the section through Quang Trach commune, Hoa Trach commune, Ba Don ward, Bac Gianh ward was invested in construction since 1994, with a total length of nearly 28km. The project has the task of leading and regulating water from reservoirs and dams to distribute and serve irrigation for more than 1,200 hectares of rice, vegetables and aquaculture for 2 crops.

Up to now, the project is seriously damaged and degraded. Many landslides and fractures have greatly affected the safety of the canal and its water supply capacity. This leads to the failure to ensure irrigation for the following years and reduces crop yields, affecting people's income. At the same time, there is a potential risk of landslides on traffic routes and threatens the safety of many houses living next to this canal.

According to the assessment of the People's Committee of Quang Binh province (old), after a long period of exploitation, the works have been damaged, degraded, and pose a potential risk of insecurity, especially in the context of climate change and unusual and extreme weather. If an incident occurs, especially a dam break, it will cause great damage to people and property of the people in the downstream area. Therefore, it is urgent to promptly allocate resources to invest in repairing, upgrading, and constructing new key items at reservoir works and important canals.

Mr. Nguyen Xuan Quang, Head of Son Tung Village, Hoa Trach Commune, said that although the management unit regularly dredged and reinforced the canal, the construction had been in serious disrepair for a long time. Every rainy and stormy season, the canal had more points and sections that were eroded, greatly affecting the lives and activities of the people. Therefore, he hoped that the province would soon have a solution to invest in repairing and upgrading the canal.

Similarly, the Trung Thuan reservoir project was built and put into use in 1982. This earth dam project with a capacity of 3.92 million m3, is responsible for providing irrigation water for nearly 350 hectares of two-crop rice. Currently, most of the project's items have seriously degraded and need to be invested in upgrading and repairing promptly, such as: Regarding the dam body, the slope area is eroded, often with large seepage, causing water loss and instability. The upstream slope, the reinforced stone layer is hit by waves, causing subsidence and erosion deep into the dam body. The downstream slope is reinforced by planting natural grass, there are no drainage ditches, leading to local erosion of the upper surface of the dam slope. The upstream dam crest has a breakwater wall built of rubble, which has now collapsed and rotted in many places, not meeting design requirements; The dam crest is designed to be 4m wide and has not been reinforced. Over time, it has eroded, creating many large holes. Some places have collapsed, so the width of the dam crest is only 3m, making it difficult to access for management, operation, and rescue when there is an incident...

Thanh Quang

Source: https://baoquangtri.vn/kinh-te/202509/can-nang-cap-sua-chua-cac-cong-trinh-thuy-loi-xuong-cap-347385b/