The amount of silt at the Yangtze River, China's longest, continues to decline, according to a recent survey of hydrological monitor centers along the river.
The latest issue of the "Yangtze River Silt Bulletin" released by hydrological monitor centers shows the average sand content dropped by 59 percent at Yichang City and 45 percent at Shashi City in 2003.
Chen Songsheng, a deputy chief engineer of the Hydrological Bureau of the Yangtze River Water Resources Committee, attributed the sustainable dropping of silt to water and soil conservation and construction of facilities for holding back silt at major reservoirs.
China has built 12,000 reservoirs on the river's upper reaches with a combined water storage capacity of more than 30 billion cubic meters. These facilities play a major role in holding up silt, which poses a severe menace to flood control efforts, the shipping industry and the lives of people nearby.
The Three Gorges Project has blocked 124 million tons of silt since it began to store water in June last year.
When China's policy-makers realized that rapid economic and population growth had turned the Yangtze into a major soil erosion area, they launched a water and soil conservation project in 1988. The project, which cost 2 billion yuan (US$240 million), has reduced eroded areas in the Yangtze River Valley by 15 percent to 500,000 square kilometers.