The Olympic rowing and canoeing centre in Shunyi was built especially for next August's Games and features a 3-km rowing lake which holds 1.7 million cubic metres of water.

Beijing sits in the arid north China plain, where water tables are falling fast due to climate change and rising consumption by farmers and booming cities.

The country has embarked on massive engineering projects to divert water from rivers feeding the south to the dry north.

It is also starting to address the serious problem of pollution of water supplies from untreated city sewage, industrial waste and farm run-off.

Xinhua said Shaanxi province, in the northwest, will build ten sewage disposal plants to reduce pollution in the Weihe River, the largest tributary of the Yellow River.

By 2010, it plans to build 40 sewage plants along the Weihe River, which receives more than 800 million tonnes of sewage and wastewater annually.