Drinking water sources in most of China's key cities have been given clean bills of health after being tested in February by the State Environmental Protection Administration.

But the situation was not so good in Chongqing Municipality in the nation's southwest, Harbin in the northeastern Heilongjiang Province and Changsha in the central Hunan Province.

The quality of all of the cities' source water was not up to the national standard, as was the case in January, the administration said in its monthly release that covers 47 key cities.

The biggest concern was the major pollutant index, which exceeded standards in terms of nitrogen and faecal coliform. They are mainly attributable to human and agricultural pollution.

However, experts say residents in the three cities should not be alarmed.

The nitrogen did not surpass levels that are harmful to humans, and faecal coliform is easily disposed of by water treatment facilities, explained Liu Tingliang, an expert with the China Environmental Monitoring Station.

The administration also said some of the water sources in Beijing, Chengdu in the southwestern Sichuan Province and Nanchang in the eastern Jiangxi Province did not meet the national standard last month.

But they only accounted for less than 10 percent of all the drinking water supplied to the cities, which is not regarded as problematic.

Therefore the overall situation in the three cities is good, the release said.

Water resources are being overused in China. For example, 60 percent of the water in the Huaihe River, 65 percent of the water in the Liaohe River water and 62 percent of the water in the Yellow River is being drawn.

And the rate of use for the Haihe River is as much as a staggering 90 percent.

All are considered key rivers. It is agreed internationally that 30 to 40 percent is the warning level for water use.

In addition to rivers, much of China's drinking water comes from groundwater sources.

Nearly 60 percent of the 669 cities in the country do not have enough water and 110 of them are suffering from serious shortages.

(China Daily March 19, 2004)