Chinese metropolitan areas will have to invest billions of dollars to update water treatment technology in order to meet China's newly-promulgated national standard for drinking water.
Under the new criteria, launched by the Ministry of Construction in June, the number of tap water test items rises to 101. The old criteria, enacted 20 years ago, listed only 35 items.
"Worsening water pollution has raised concerns for the quality of tap water. If tap water for household use doesn't go through deep-processing treatment, it will contain organic pollutants and dangerous chemicals," said Wang Zhansheng, an expert with the Chinese Academy of Water Supply and Drainage.
A conservative estimate made by the China Water Association shows that an investment of no less than 50 billion yuan (6.25 billion US dollars) will be needed if China adopts deep-processing technology for a comprehensive water treatment capacity of 100 million cubic meters.
With the growth of Chinese cities, daily urban water supply may reach 432.7 million cubic meters by 2010. However, at that point, the country's comprehensive urban water treatment capacity in public water treatment plants will only be able to cope with 282 million cubic meters, according to the association.
Big cities such as Chongqing, Guangzhou, Shanghai and Hangzhou have had to invest heavily to introduce deep-processing technology, which uses ozone and active carbon to kill organic pollutants in water. These cities aim to bring the quality of tap water up to par with European drinking water standards in the next couple of years.
Chongqing Municipality in western China, for example, plans to spend 4.45 billion yuan (556 million US dollars) before 2010 to purify water resources. One billion yuan will be used to purchase deep-processing equipment.
Chongqing draws water from the Yangtze and Jialing rivers that traverse the city. A recent sample test conducted by experts with the Ministry of Science and Technology showed that tap water sampled in a downtown residential area contained 80 strains of the 101 pollutants forbidden by the new drinking water quality standard.
According to a recent cross-sectoral survey carried out by experts with water authorities and test institutes, 61 out of China's 181 large and medium-sized cities depend on exploration of underground water, 40 cities use both ground and underground water, and 80 cities completely rely on ground water as the source for drinking water.
Of the 1,300 rivers surveyed in 2004, 59.4 percent achieved a quality rating above grade III. This was three percentage points down from the 2003 rating, it said.
This shows that many of these cities are sourcing water with quality below grade III, the country's minimum standard for drinking water. These cities will face tough administrative pressure to update and improve their water technology, according to experts.