An analyst tests the quality of a water sample. (Photo/Xinhua)
A water quality expert from Beijing claims her family has not drunk the city's tap water for more than 20 years, reports People's Daily Online, the website of the Communist Party mouthpiece.
Zhao Feihong, head of the Beijing Institute of Public Health and Drinking Water, says her family uses different types of mineral water to drink, to make tea and to cook rice. Her husband is also a water expert who works at the Drinking Water Industry Committee of the National Development and Reform Commission's Public Nutrition and Development Center.
The couple says after researching the water content and quality of Beijing for years, they have developed a habit of never allowing tap water to touch their lips.
"We are probably the family that is most mindful about healthy drinking water," Zhao said. "We are in the habit of not drinking water from the tap, as the quality of tap water is not as good as it was five or six years ago."
According to Zhao, recent tests show that the nitrate content of Beijing's tap water is more than 9 milligrams per liter, very close to the national standard of 10mg per liter. While it remains below the maximum standard, such a high nitrate concentration can present a hazard to human health, especially as most nitrates come from garbage, filtrate particles and excrement.
Five or six years ago Beijing's tap water had a nitrate content of only 1-2mg/L and only around 4mg/L in 2011, Zhao said, adding that it is beyond dispute that Beijing's water quality has been deteriorating.
Zhao initially researched health products such as fish oil but switched her interest to water in the early 1990s. In 2007, she joined a volunteer walking group aimed at testing all-natural water resources across Beijing.
In the 1980s, Beijing's best water was at the Miyun reservoir at Yanshan, around 100 kilometers northeast of the capital, Zhao said. Back then, the water quality there could have passed tests in Germany, the country said to have the most stringent standards in the world, she added.
But when Zhao returned to the area in 2011 she saw that water quality had changed significantly. Amendments to China's water quality standards mean that the highest-grade water now would have only been third-grade water back in those days, she said. The local Guanting reservoir, one of the country's largest water sources, has become so heavily polluted that it has been classified grade four and is used only as emergency backup.
Beijing's water quality has dropped so much over the years because the city's water sources are too complex, Zhao said. In 2010, a regional drought forced the city to source water from reservoirs in the neighboring provinces of Shanxi and Hebei. Although Beijing paid a lot of money for that water, most of it was fourth-grade and even had dead fish floating on it, Zhao said.
The water in Miyun reservoir first goes through the processes of coagulation, filtration and disinfection before being passed to one of Beijing's 10 large processing plants, where it will be mixed with groundwater and distributed to residents.
Beijing's groundwater is relatively clean, Zhao said, but it now also needs to be processed because it is too "hard," meaning it contains too much calcium carbonate, which can cause shampoo to become sticky and soap to turn into soap scum, as well as cause skin rashes in children.
Beijing's water supply, Zhao said, has been dropping off dramatically at an average of 500 million cubic meters per year. The Beijing Water Authority recently revealed that the per capita quantity of water in the city has dropped to just 100 cubic meters, only 10% of the internationally recognized water shortage warning line of 1,000 cubic meters per person.
It has also become more difficult to obtain groundwater in Beijing. Between 1999 and 2009, the average depth of water wells increased from 12 meters to 24 meters. Currently, the average depth is around 30 meters.
Professor He Weifang from Peking University said Beijing's tap water has always been problematic, although the quality of the water across the city is very uneven. Beijing lacks good rivers and lakes, clean places with lush growth, He said, adding that most of the pristine places in rural areas have all become overcrowded.
Zhao Feihong 趙飛虹
He Weifang 賀衛方