The water ran over Nguyen Thi Anh's hands as her granddaughter poured slowly from a plastic bottle. The 57-year-old woman used the water to rinse the dishes after cleaning them with tap water.

In the last few days she has been unable to use tap water for much. Last night she had stayed up until midnight with her children to collect water from a tanker truck dispatched by local authorities.

"I was sleeping when the security guy knocked on the door and told us the water tanker was coming. We immediately went downstairs to get some water. I was so tired and could not wake up early this morning."

But the good thing was that the family had enough fresh water, she added.

Anh is one of hundreds of thousands of Hanoians who are trying to get used to bottled water for drinking and cooking to brushing teeth, since they cannot use water from their taps.

Hanoians wait to collect potable water from a tanker on October 15, 2019. Photo by VnExpress/Giang Huy.

A senior government official confirmed on Tuesday that the water supply across the city’s south-east has been contaminated with styrene, a carcinogenic.

The smell first appeared after a truck dumped oil into a branch of the Red River, a few hours north-east of Hanoi on October 8.

Hoang Van Thuc, deputy head of the Vietnam Environment Administration, called it a "serious and irresponsible act of vandalism". The water pollution has affected 250,000 housesholds in Hanoi.

His agency said people should using water supplied by some companies "only for washing and showering, not cooking or drinking."

Sleepless night

From tea stalls on the street to living rooms, the talk is only about drinking water.

"Many young couples living next door have spent a lot on bottled water despite their limited income, and I feel sorry for them," Nguyen Thi Vuong, 56, of Thanh Xuan District said.

Her 10-member family has an underground tank which has provided them with water the last several days, but she is pessimistic about the situation when it runs out since bottled water is not available anywhere nearby.

The demand for bottled water has been skyrocketing since last weekend when some people realized their tap water was stinking.

After authorities admitted there was a problem on Tuesday, convenience stores and supermarkets in Thanh Xuan, Ha Dong and Hoang Mai districts quickly ran out of bottled water.

Bottled water flies off supermarket shelves in Hanoi on October 16, 2019. Photo by VnExpress/Anh Tu.

People have been stocking up, and water prices are skyrocketing.

"My son called many stores to order some 20-liter bottles, but they cannot promise since they have more than 200 pending orders," Anh said.

So her whole family had to stay up until midnight and fill water from the tanker in plastic bottles, buckets and every other container they had.

In their warning to around half the capital’s residents, authorities also indicated they would supply water by tankers as a temporary measure.

The Hanoi Water Company’s hotline was jammed on October 15 with more than 2,000 calls from people asking for water.

In the middle of the city, thousands of people, young and old, queued up to fill water from the tankers, but had to register and wait for hours before getting any.

Le Anh Dung of Hoang Mai district, said: "We could not sleep last night since we had to wait for water from tankers."

Since the beginning of this week some schools in the area have also been getting water from tankers. Education authorities have instructed schools where tap water is polluted to buy bottled water or from other sources.

Some people not wanting to risk their children's health have moved to friends' or relatives' houses elsewhere in the city to avoid the crisis.

Dung said: "We are afraid of the polluted water because we have two kids. My son's kindergarten is in the area affected by the pollution, so I sent him to my hometown."

He and his wife are unable to focus on anything except news about water. They have been longing for some good news from the authorities, but there has been nothing so far.

"It is stressful," Dung added.

Anh, who retired from work last year, said she spends the whole day in the lobby of her apartment building looking for water tankers, something no one in the area wants to miss these days.

She cannot see her younger grandson since he was sent to his uncle's house in Long Bien district last weekend.

It has been a week since the lives of thousands of people were severely disrupted by the obnoxious smell coming from their tap water.

Tests have found that the water contains high levels of styrene, thought to be carcinogenic.

A person collects potable water from a tanker. Photo by VnExpress/Giang Huy.

Viwasupco, which processes water from the Da River to supply Hanoi, was aware of the problem even before people began to detect the strange smell, but kept supplying water anyway.

Solutions for the crisis are not around the corner.

"In many countries around the world, including Vietnam, the treatment technologies used for producing drinking water from rivers are only efficient in removing tiny particles, minerals and harmful microorganisms," An Huynh of the Environment and Natural Resources Faculty at the Ho Chi Minh City University of Technology said.

"Therefore, the removal of chemicals that do not easily mix with water, such as petroleum products, require additional time and work."

Anh said: "I have not seen any water tankers today, hopefully they will come in the evening. I have bought some more buckets to store water."

Her son had brought home a 20-liter bottle.

He went downstairs, waiting for good news about water tankers’ arrival, while his mother prepared for dinner.