In fact, in recent years, some irrigation canal systems have been encroached upon to build houses, barns, etc. and waste has been discharged indiscriminately into canals, obstructing the flow, especially at key irrigation works. The report of the Department of Agriculture and Rural Development also stated that violations of the protection area of irrigation works mainly include discharging wastewater and domestic waste into the works; planting trees on the banks of canals, building fences, building houses and works within the protection area of the works, etc.
In particular, there are a few cases such as some construction stone processing enterprises located in Quy Hop district directly discharging production wastewater into Tong Huong canal; households in Dong Ha hamlet, Dien Van commune (Dien Chau) discharging frozen goods processing wastewater into the local irrigation canal. Although these cases have been reminded and reported to the local authorities by the construction management unit, they still recur, causing difficulties in handling. Some irrigation works are located close to residential areas, due to low awareness of the people, along with the locality's laxity in implementing legal regulations on protection and exploitation of irrigation works, preventing and handling violations is difficult.
The main river system in Hoang Mai town and Quynh Luu district has been silted up for many years, making drainage difficult, especially on days of heavy rain and flooding. As a result, when there is heavy rain, combined with the discharge of floodwater from Vuc Mau lake, the water rises rapidly, causing many residential areas to be deeply flooded for many days. Recently, during the flood at the end of September, in Hoang Mai town, one of the causes of deep flooding was because at the construction site of Hoang Mai 2 bridge on the North-South expressway and the southern branch of Hoang Mai river on the coastal road, the construction units built a service road across the flow; when the water from Vuc Mau lake poured into Hoang Mai river and could not drain in time, it was combined with water from Quynh Vinh, Quynh Loc communes, and Quynh Thien ward flowing through Nha Le canal, which was blocked.
Another reality is the situation of households encroaching and building houses within the protection area of the Vach Bac drainage canal and the N18A canal in Do Thanh commune (Yen Thanh). Although the authorities and local governments have drawn up many administrative violation records and issued decisions to impose administrative penalties, they have not yet been completely handled. This is the cause of flooding in communes along the Vach Bac canal of Yen Thanh district, such as Lang Thanh, Hau Thanh, Phuc Thanh, Van Thanh, Ma Thanh communes, etc.
Through discussion, Mr. Nguyen Truong Thanh - Head of the Irrigation Sub-Department, Chief of Office of the Provincial Steering Committee for Natural Disaster Prevention, Search and Rescue and Civil Defense said: Currently, some drainage systems, main dykes, and internal irrigation systems in Quynh Luu district and Hoang Mai town are silted up; the river dyke systems are not closed, so when there is heavy rain (exceeding the actual design flood frequency of 5%), they cannot drain in time; or the sea dykes can only withstand level 10 storms, not larger storms and super storms. To solve this problem, the University of Irrigation has recently researched, evaluated and proposed solutions to ensure that Quynh Luu district and Hoang Mai town are not flooded. Through survey and evaluation, it is shown that to solve the problem, it is necessary to invest nearly 2,000 billion VND to synchronously upgrade the infrastructure system to prevent flooding. Thus, this is a big challenge for the locality.
Regarding the current situation of many canal systems being encroached upon, Mr. Nguyen Truong Thanh commented: “According to the principle, the drainage canals must ensure their cross-section, but some drainage canals have been filled up, the flow is blocked, the encroachment on the riverbed… has greatly affected the flood drainage work. Therefore, it is necessary to completely resolve this situation.”
Lakes and dams are structures formed by dams and related structures to store water, with the main tasks of regulating water flow, cutting and reducing floods, providing water for agricultural production, industry, daily life, etc. and improving the environment. However, in order for lakes and dams to have flood resistance capacity, they need to be invested in repairing and upgrading to avoid leakage and landslides in the dam body when there is heavy rain and high water levels.
According to Mr. Nguyen Truong Thanh, the large lakes and dams in the province have been basically repaired and upgraded to meet flood prevention requirements; however, the small reservoir systems managed by localities have not yet been upgraded, ensuring safety in disaster prevention and control is not high, and the risk of incidents during heavy rains is very high. For example, during the recent floods, some lakes and dams had incidents, forcing local authorities to mobilize forces and equipment for reinforcement.
For example, on the night of September 28, due to the circulation of storm No. 4 causing heavy rain over a large area, the water level in ponds, lakes and dams in Quynh Luu district rose very quickly. At Hoc Coi dam in Quynh Tam commune, a collapse appeared right at the dam body, forcing the local government to mobilize people and forces to reinforce it that night. Mr. Nguyen Xuan Quang - Chairman of Quynh Tam Commune People's Committee said that when the incident occurred, in addition to the on-site forces, more than 100 officers and soldiers of Brigade 215 stationed in the area had to be mobilized to promptly reinforce the dam body.
Also during the above-mentioned floods, many lakes and dams in highland districts such as Quy Chau, and plain districts such as Yen Thanh... were also at risk of cracking, and local authorities had to send forces to stand by and respond. For the river dike system in Thanh Chuong and Hung Nguyen districts, serious incidents occurred when the river water rose, overflowed the dike, threatening many residential areas. Specifically, on September 29, 2022, the Giang River dike section through Lien Khai hamlet, Thanh Lien commune (Thanh Chuong) was flooded for a distance of more than 200m; Thanh Chuong district had to mobilize military units stationed in the area and militia and self-defense forces to urgently use earthen bags to reinforce, preventing the risk of flooding affecting hundreds of households. Mr. Phan Ba Ngoc - Party Secretary, Chairman of Thanh Lien Commune People's Committee said that if the Giang River overflowed this dike section, it would flood 520 households in the commune. Therefore, the State needs to soon invest in upgrading this dike section to ensure people's safety every time the rainy and stormy season comes...
According to Mr. Le Dinh Thanh - Vice Chairman of Thanh Chuong District People's Committee, the biggest concern during the flood season in the district is still the situation of river water overflowing the dike. If not handled promptly, landslides will occur, causing huge consequences for houses and properties of people living along the dike. Currently, when the water level on the rivers rises during heavy rain, the district must immediately direct localities to regularly monitor the water level to have timely response plans to unpredictable situations...
Thus, although the shortcomings and limitations in management and exploitation of the capacity of the drainage and flood prevention systems have been identified, solutions and plans to overcome and promote works to prevent high risks during the flood season for localities are still a big challenge...
