Beijing's future water resources are already under threat from pollution.
The source of the problem is a river over a thousand kilometers from the capital originating in central China's Shaanxi Province. The Han River flows 600 kilometers east to the Danjiangkou Reservoir, which, in five years time, will contain 33.9 billion cubic meters of water to cater to the needs of thirsty Beijing, Tianjin and parts of Hebei Province, all in north China.
The Han River contributes over 70 percent of the reservoir's water, so any changes of its quality or volume would have a direct bearing on drinking water of the nation's capital.
It flows through the three cities of Hanzhong, Ankang and Shangluo and 27 counties populated by nine million people in Shaanxi for over 600 kilometers.
Currently, there is a small number of industrial enterprises along the basin, but experts fear this will not last long as economic development stretches the river's sewage disposal capacity.
There are only two sewage disposal plants along the Han River's Shaanxi section, in Hanzhong and Ankang, with a combined disposal capacity of around 30 million tons a year, far less than the 60 million tons of sewage discharged by the two cities.
Lack of funds is a major obstacle to the building of more sewage disposal plants and corresponding pipeline networks to collect waste water from thousands of households in the cities, as they cost usually millions of U.S. dollars, said Li Xingmin, vice-director of the Shaanxi environmental protection bureau.
Li estimated the 27 counties discharge about 100 million tons of sewage every year directly into the Han River. A strip of dark water is often found when the river flows through urban areas and officials are concerned it will become longer and wider as the population and economy grows.
In order to protect the water quality of Danjiangkou Reservoir, the Chinese government has issued a plan requiring major cities near the reservoir to improve the way they develop urban infrastructure.
An inspection team of the Standing Committee of the National People's Congress (NPC), China's legislature, recently visited Shaanxi to check the implementation of three environmental protection laws on solid wastes, water and air pollution.
Local businesses' eagerness for expansion has also posed serious threats to the river. The waste discharge volume has been rising since 2000 along with a growing number of enterprises in industries such as paper making,non-ferrous metal mining and construction material making.
Xu Yongqing, head of the inspection team and member of the NPC Standing Committee, cautioned that water pollution treatment, though progress has been made, needs to be improved, urging local governments to work hard to ensure that objectives in the 11th Five-year Plan could be realized.
According to the plan, the total discharge volume of major pollutants must drop by 10 percent while the economic scale expands by 40 percent during 2006 to 2010.
To meet this objective, Shaanxi has outlined a plan to build an urban waste disposal plant in each county along the river basin and try to ensure 70 percent of urban garbage is properly disposed.
But such a process might be arduous, said Li Xingmin, adding that lack of environmental protection law enforcement is a major obstacle, urging the government to allocate more funds for environment protection undertakings.
It is a process that requires joint efforts from all government departments and the whole society, he said.