Three Gorges Dam murky. In 1997, the Three Gorges area had 10% forestation, down from 20% in the 1950s. Research by the United Nations Food and Agriculture Organization research suggested that the Asia-Pacific region would, overall, gain about of forest by 2008. That is a significant change from the net loss of forest each year in the 1990s. This is largely due to China's large reforestation effort. This accelerated after the 1998 Yangtze River floods convinced the government that it must restore tree cover, especially in the Yangtze's basin upstream of the Three Gorges Dam. Concerns about the potential wildlife impact of the
Three Gorges Dam spillway gates of the dam might pose a risk of cavitation, similar to that which severely damaged the poorly designed and cavitating spillways of the Glen Canyon Dam in the US state of Arizona, which was unable to properly withstand the Colorado river floods of 1983. However, 163,000 concrete units of the Three Gorges dam all passed quality testing and the deformation was within design limits. An experts group gave the project overall a good quality rating. In order to maximize the utility of the Three Gorges Dam and cut down on sedimentation from the Jinsha River, the upper course