The Hanoi People’s Committee has instructed the city’s Department of Agriculture and Rural Development and relevant agencies to think of solutions to restore and regenerate the local fishery resources.

The fishery resources have declined seriously recently due to uncontrolled exploitation and pollution.

Dr Pham Ngoc Dang, deputy chair of the Vietnam Association for Nature and Environmental Protection, noted that the pollution in rivers and lakes in Hanoi has become more and more serious.

The West Lake, for example, has been degrading rapidly in recent years. In the 1960s, the water there could meet the A standards with the BOD5 (biochemical oxygen demand) content lower than 6mg/l. But the water quality now ranks at B1 and B2 in accordance with international standards with the BOD5 content of 23mg/l. 

“The highest BOD5 content, at 35 mg/l, could be found in the area near the Thanh Nien Road,” Dang said, adding that water can meet the B2 standard if the BOD5 content is not higher than 25mg/l.

More than 10 years ago, when conducting a scientific research work assigned by the Ministry of Natural Resources and the Environment, Dang and some other scientists suggested building sewers around West Lake to prevent rubbish and waste water from flowing into the lake.

The scientists also warned that the pollution level at the West Lake would continue increasing unless measures were taken.

In 2014, the BOD5 content in West Lake had decreased by 50 percent.

However, the water samples taken from areas near the lakeshore still showed high concentration of pollutants BOD, COD (chemical oxygen demand), NH4+ (ammonium), NO3- (nitrate) and PO43-, twice as much the concentration of the water taken in the middle of the lake.

The difference in the coliform concentration between the water in the middle of the lake and near the shore was even higher, about 4 times.

As waste water from some restaurants and construction works continues flowing into the lake, the pollution level continues to rise.

“The only solution to the environmental problems in Hanoi lies in people’s awareness of the necessity of protecting rivers and lakes,” Dang said. 

“If we can prevent 100 percent of waste water from running into West Lake, the quality of water in the middle of the lake and near the shore will be the same, and the lake will be able to revive more quickly,” he said.

“The pollution in West Lake is at the red alarm level. If no proper solution can be found, it will become a stagnant pond,” he added.

Dat Viet