[Photo/Xinhua]

The central route will transport up to 1.88 billion cu m of water to the capital every year by 2020, the water authority report said.

Beijing has also been upgrading its wastewater treatment facilities with advanced technology and now uses up to 860 million cu m of recycled water a year, mostly in industrial production, landscaping, and sanitation, the report said.

The authority predicts the annual production of recycled water will increase to 1.2 billion cu m by 2020, making the capital's second-largest water source.

Along with efforts in water conservation, Beijing will see daily water supplies to downtown areas reach 4.8 million cu m by the same year, the report said.

Last year, the maximum daily water supply was 3.1 million cu m, according to data from the Beijing Waterworks Group, the biggest supplier of drinking water. However, by 2020, Beijing Water Authority says, the capital's water resources will be at least 4.35 billion cu m, and at most 5.08 billion cu m.

Yanqing used 63 million cu m of water last year. Based on that, the extra water needed to make snow and for other Games-related purposes would only account for 0.23 percent of the county's annual consumption, Dai said.

In addition, he said, the county has stable supplies from four reservoirs: Baihepu, Foyukou, Gucheng and Yudushan.

Baihepu is the fifth-largest reservoir in Beijing. After the diverted water reaches the reservoir, it now provides drinking water for Yanqing. Before, the water had to be transferred to Miyun Reservoir to guarantee quality, the water authority said.

The county has started construction on a new processing plant for drinking water beside Baihepu. The facility is scheduled to go into action in 2017, increasing the daily supply to 95,000 cu m, enough to cover demand in the entire county.

Zhang Tong, deputy dean of the Beijing Institute of Water, said she also believes the Olympics would not adversely affect water supplies or the environment, as "Yanqing is in a basin, and has a relatively independent geographic situation".