On July 19, regarding the situation of natural fish, fish in cages on the Hieu River, Thach Han River section passing through Dong Ha ward, Cua Viet commune, Nam Cua Viet commune, Trieu Binh commune dying abnormally with dozens of tons, the Department of Agriculture and Environment of Quang Tri province said that there have been results of water quality inspection and disease testing of dead fish samples.
Accordingly, on July 9 and July 10, functional agencies took 12 water samples at 10 locations along with 4 dead fish samples (including farmed fish, cages and wild fish) on the Hieu and Thach Han rivers.
Test results from the Central Center for Diagnostic and Veterinary Testing I for fish samples all gave negative results for neurogenic disease and TiLV virus disease. Based on this, the Department of Agriculture and Environment of Quang Tri province affirmed that mass fish deaths were not due to epidemics.
Meanwhile, water quality monitoring results revealed that the water source is having problems when the content of nutrients and organic matter increased sharply compared to the same period in previous years. Compared according to standards, many water samples have total nitrogen parameters at level C or D (bad and very bad levels). The total phosphorus index is also at level C or D at most monitoring points.
Some locations also recorded high levels of suspended solids and coliform microbiological indices reaching levels B, C and D.
The Department of Agriculture and Environment assessed that the above parameters reflect that the water quality tends to decline significantly, causing disadvantages to the living environment of aquatic products. This unusual change increases the risk of affecting the health and resistance of caged shrimp and fish as well as natural aquatic products.
Therefore, the Provincial Sub-Department of Fisheries and Fisheries Resources Surveillance had to issue urgent official dispatches requesting people to temporarily stop supplying water from the Hieu and Thach Han rivers to farming ponds.
Determining that fish deaths are due to abnormal water quality, not due to epidemics, the Department of Agriculture and Environment has issued a document proposing to the People's Committee of Quang Tri province to assign the Provincial Police to preside over and coordinate with relevant units and localities to conduct investigations and verify to clarify the cause to find negative impacts on water sources" - the leader of the Department of Agriculture and Environment of Quang Tri province informed.
Previously, Lao Dong Newspaper reported that from July 4th, people along the Hieu and Thach Han rivers discovered abnormal color streaks in the river water. After that, fish raised in cages on the river stopped eating, wriggled and then died en masse. In Cua Viet commune alone, more than 25 tons of farmed fish of people died.
Fish deaths first appeared at the headwaters of the Hieu River section passing through Dong Ha ward, then to Cua Viet commune and then to the Thach Han River section passing through Nam Cua Viet commune (the Hieu River flows from Dong Ha ward, mixing with the Thach Han River before flowing into the sea). In Trieu Binh commune, people also discovered some types of dead fish and eels on the river.
Faced with the abnormal fish deaths, people are heavily damaged, and they hope that functional agencies will intervene to clarify the cause. Besides, consumers are concerned and do not know whether eating fish on the Hieu and Thach Han rivers affects health.
