Le Van Duc, director of Hanoi’s Construction Department, said at a meeting on November 1 that a shift in the weather was the cause of the mass fish deaths in Linh Dam Lake on October 26.
“It was very hot in the morning and then rained in the afternoon,” Duc said. “The lake is among the less polluted in Hanoi.”
Thousands of fish went belly up along the two-kilometer edge of the lake in Hoang Mai District, creating a foul stench on October 26.
|A Hanoi's environment worker collects dead fish from Linh Dam Lake on October 27. Photo by VnExpress/Ngoc Thanh
Joggers noticed the problem at around 8 p.m. and dead fish covered the embankment a few hours later. Carp as large as five kilograms could be seen floating in the water.
Workers from Hanoi’s Sewerage and Drainage Company have collected around 200 kilograms of dead fish so far.
“200 kilograms of fish dying in a lake of more than 70 hectares is normal,” Duc said.
His department is still investigating a bigger pollution problem on West Lake, the largest in Hanoi, after 200 tons of dead fish were collected over several days in early October.
The inspection covers all 99 hotels and restaurants and 27 sewage pipes around the lake.
A study by the Institute for Environmental Science and Development recently found that all of Hanoi’s urban lakes and waterways are heavily polluted.
The city hopes to resolve the problem with help from a US$726-million sewage treatment plant.
Construction began early this month and is slated for completion in three years. The system is designed to treat 270,000 cubic meters of sewage every day from the Lu, To Lich and Nhue rivers in a bid to bring them back to life.