Saturday, May 12, 2012
Shanghai Municipal Government: Why Tap Water is Still a Problem
Many people in China are accustomed to boiling tap water before drinking it because they think this can make it clean, but that may not be the case, according to an investigative report.
Beijing-based Century Weekly reported this week that the quality of water from at least 1,000 tap water providers in Chinese cities was below standard, citing Song Lanhe, chief engineer of the Urban Water Quality Monitoring Center under the Ministry of Housing and Urban-Rural Development.
Song's comment was based on a drinking water survey conducted by the center in 2009.
"Among more than 4,000 water plants we surveyed, we found the water provided by over 1,000 plants was disqualified," said Song, who added that the quality of urban tap water had not improved much since the survey.
The ministry has not yet released the survey results. The report said this indicated that the underlying truth might be much worse.
"I am not authorized to tell you the exact figure (of tap water's qualification rate)," Song said.
The report went further, saying that the figure might be around 50 percent.
Online comments on sina.com.cn yesterday criticized the country's inability to provide safe water, with many people saying they were worried about disqualified tap water that could lead to serious diseases due to high CODmn and untreated remnants of heavy metals.
CODmn is an index used to gauge the amount of organic compounds in water.
One comment claimed that tap water in parts of China could cause serious diseases because of the chemical companies along the upper reaches of major rivers.
Wang Zhansheng, a Tsinghua University professor, said the accumulation of organic compounds in the human body could lead to cancer and other diseases.
At the end of 2009, 98 percent of the plants surveyed were still treating water using conventional methods including coagulation, sedimentation, filtration and disinfection, but experts argue these simple steps can not treat heavy metals and organic compounds.
Boiling water can't get rid of heavy metals and may even concentrate the pollution.
Song said outdated water pipes were also likely to cause pollution. "Old pipes are easy to corrupt and become encrusted with scale, which will produce microbial bacteria and cause pollution," said Liu Wenjun, a researcher with Tsinghua.