ĐÀ NẴNG –  Đà Nẵng City Department of Natural Resources and Environment on Wednesday announced that the change in weather resulted in fish death in the Phú Lộc River.

This change led to a drop in the amount of dissolved oxygen in the water, the department added.

At the water drainage of Bàu Trảng lake into Phú Lộc River, around 50kg of fish were found dead earlier this week. The initial cause, according to the department, was the decreasing amount of dissolved oxygen at 0.59 – 0.91 mg/l, lower than the regulated level of 4 mg/l.

The department directed the Đà Nẵng City Sewerage and Waste Water Treatment Company to collect dead fish to be processed at the Khánh Sơn dumping yard and to spread lime over the Phú Lộc River area.

It also asked the Centre for Monitoring Environmental Resources to collect water samples and continue observing the lake’s water quality from October 4 to 6 to evaluate the pollution level.

Abnormal fish death has been witnessed in the Phú Lộc River since October 2. Mai Mã, director of the company, said that the number of dead fish was lower than in previous cases.

Before that, on August 21, tonnes of fish in the river died due to serious water pollution.

Fish death in Huế

Mass fish death also occured in breeding cages in Bồ River in central Thừa Thiên-Huế Province.

Nguyễn Thị Mỹ Dung, a breeder, said she found the dead fish Wednesday morning in her floating cages on the section of the Bồ River passing through the province’s Hương Toàn Commune.

“I found a number of fish had died while the others were palpitating. We rushed to harvest the palpitating fish for sale to reduce losses,” she said.

Some 50 breeders in the commune had dead fish in their cages. The fish weighed some 4kg and were almost ready to harvest.

We are worried about the losses due to the dead fish, Nguyễn Thị Gái, another breeder, said, adding that the fish were meant for consumption during the upcoming Tết holiday (Lunar New Year).

Ngô Quang Thảo, the commune chairman, said the cause of the mass fish deaths in cages is being determined, but he suspected the high number of fish in each cage led to shortage of oxygen in water.

“Locals blamed the Hương Điền power plant for not releasing water, resulting in reduced flow of the river downstream and leading to a fall in percentage of oxygen. But this must be tested,” Thảo said.

Hương Điền is a power plant built on the upper part of the Bồ River. Thảo added that local breeders have ignored warnings against the high population in each cage despite the mass fish dead last April. — VNS