Hanoi has advised residents in several districts not to use tap water sourced from the Da River for cooking and drinking after high levels of styrene were discovered. — Photo nld.com.vn

The districts include Thanh Xuan, Ha Dong and a part of Nam Tu Liem, Hoang Mai, Cau Giay, Thanh Tri, Hoai Duc, Thanh Oai, Dan Phuong and Ung Hoa.

The warning was made by Le Van Duc, director Hanoi’s Department of Construction, at a press conference held on Tuesday.

People could continue to use the water for washing clothes and bathing, he said.

The municipal People’s Committee has asked the Hanoi Clean Water Company to provide fresh water for affected residents.

To ensure the safety of water from the Da River, the city has asked the Song Da Water Investment JSC to immediately tackle pollution on the upstream section in Hoa Binh Province’s Ky Son District, as well as Dam Bai Lake.

The company was also instructed to flush the system it uses, including tanks and distribution pipelines, and review its operations and water quality control equipment, and replace where necessary.

Surveillance cameras to monitor possible incidents were also needed.

The People’s Committee has authorised the Department of Construction to co-ordinate with the Department of Health and local authorities to monitor the work. A plan should also be put in place to monitor water from other sources, such as the Duong River.

Last Thursday, residents in some districts west of Hanoi detected an unpleasant smell coming from their tap water. Many of them have stopped using tap water and are buying bottled water instead.

Hanoi's Health Department subsequently took water samples for testing. The test results showed the levels of styrene in the water were higher than normal, meaning it was unsafe, said Hoang Duc Hanh, deputy head of the department.

However, it was not clear how styrene affected people’s health, he said.

The reason for the smell was caused by a significant amount of used oil illegally dumped into an upstream section of the Da River in Phu Minh Commune, Ky Son District. It spread to the stream and Dam Bai Lake, which supply water for the company.

Spilled engine oil blamed for foul tap water in Hanoi: official

Authorities have been asked to find the truck that was used to pour engine oil into a spring near Song Da Water plant. The oil spill has been identified as the cause of the foul smell of the tap water used to supply residents of Hanoi.

Da River water safe for use despite strange smell

The strange odour in domestic water detected by residents in some districts west of Hanoi was due to an increase of chloride used to disinfect source water from the Da River.

VNS