The Hanoi government needs to learn experience from Vinaconex Water Supply JSC (Viwasupco)'s water contamination scandal last month and build scenarios to quickly respond to similar incidents, Chairman of the Hanoi People's Committee Nguyen Duc Chung said at a meeting on November 4.

Chairman of the Hanoi People's Committee Nguyen Duc Chung speaks at a meeting on November 4. Photo: Vo Hai

Chung stressed that the local government is responsible for the incident. However, Viwasupco must be held accountable for hiding the incident.

"Viwasupco knew the incident and asked workers to use a lot of chlorine to treat the water pollution. On October 15, when the city made public the result tests of water samples, the company still refused to admit,” Chung said.

He noted that he and his deputy Nguyen The Hung had to directly call Viwasupco’s leaders and major shareholders who then admitted that the company’s water source was contaminated with used oil.

According to Chung, Viwasupco operates Hanoi’s first surface water plant but it was built in the neighboring province of Hoa Binh. Among all current surface and underground water plants in Hanoi, Viwasupco’s plant is the only one that does not have an automatic monitoring system and exploits water from Dong Bai lake in Ky Son district of Hoa Binh which is also use for irrigation.

Hanoi's mayor shared the view that Viwasupco should not use Dong Bai lake’s water, but to separate the water intake system from the Da river for its water plant.

Chung said that Viwasupco use Dong Bai lake’s water so that it does not have to treat mud and reduce production costs.

The mayor noted that as soon as residents in some Hanoi districts voiced concern over a strange smell of tap water, the city’s authority set up an interdisciplinary delegation to inspect, collect water samples and send them to the Ministry of Health and the Vietnam Academy of Sciences for testing to find out the cause.

Tests of the smelly water by authorities later found that the level of styrene, an organic compound that is potentially carcinogenic, was 1.3-3.6 times higher than normal. Hanoi's authority recommended that clean water sourced from Viwasupco's plant is unsafe for cooking or drinking.

Last week, the Hanoi People's Committee assigned the municipal Department of Construction to study the establishment of a center for managing, regulating and supervising clean water supply in the city.

Viwasupco currently supplies potable water to 250,000 families in 10 districts in southwestern Hanoi. Around one million people or one eighth of the capital city's residents depend on its supply.

Hanoi mayor also requested Viwasupco to install an automatic monitoring system and this company promised to complete the installation in the next three months.