In the face of criticism from environmental groups, a senior government official reiterated last Friday that China will make every effort to protect the environment in the area of the Three Gorges Reservoir and the entire Yangtze River.

"We must protect the river," said Pu Haiqing, director with the office of the Three Gorges Project Construction Committee.

Since China started building the Three Gorges Reservoir, the largest in the world, in 1994 on the Yangtze River, criticisms of its effects on the environment have been unceasing.

The Yangtze, China's most important river, feeds approximately 55 percent of Chinese population, and the economy in its valley accounts for 40 percent of the nation's total. "If the river were to be badly polluted, the results will be disastrous," Pu said.

China's central and local governments have said they are deeply concerned over the project's environmental issues. They have sought to prevent any harm the project may bring to the air, soil, water and living creatures, Pu said.

A comprehensive monitoring system has been established around the area to monitor the environment as construction continues, with a yearly report being published for the last nine years.

According to the reports, weather conditions have improved, water quality remains unchanged, and soil erosion drops by 1 percent each year.

The reports do show problems, however. The reservoir, like a giant water tank, will only allow the water to refresh itself 11 or 12 times each year, leading to the increased possibility of water degradation. The amount of sludge will also increase.

The huge construction project has significantly improved water transport and stimulated local people to buy vessels for business - bad news for the environment. Roughly 100,000 ships and boats ply the area's waters, ejecting 50,000 tons of garbage and up to 20 million tons of waste water into the Yangtze River each year.

A budget of 39 billion yuan (US$4.7 billion) was approved last year to build 28 waste treatment plants, 26 of which have been completed.

Government officials say that it will take time to accurately assess what exact impact the world's largest water project will have on the environment. Top scientists and experienced scholars are involved in relevant research programs, and "officials and experts are keeping a close eye on the latest developments and trying to promptly resolve any possible problems," Pu said.

Pu said it was of vital importance to improve people's environmental awareness, which he believes is fundamental for the protection of the river.