BEIJING -- The large-scale greening project in Beijing ahead of the Beijing Olympic Games did not strain the water resources, said an government official here on Thursday.

Bi Xiaogang, deputy director of the Beijing Municipal Bureau of Water Affairs, said recycled water became the most important resource for greening.

"Beijing used to rely on surface water and underground water for water supply but now recycled water is playing an increasing important role," said Bi in the Games' Main Press Center which opened on Tuesday.

"In recent years we have carried out a lot of greening projects as we have introduced water saving technologies from the international communities. Recycled water now is the leading water supply for greening projects," he said.

Bi said recycled water accounted for 60 percent of water consumed on greening project.

"Right now about 20 million square meters of lawn is irrigated with recycled water," Bi said.

Beijing has built 25,000 ha. of green belts and planted 12,600 ha. of trees besides thousands of lawns dotted in the city of over 17 million people.