Thanks to comprehensive treatment, surface subsidence in Shanghai, the country's largest industrial and business center in east China, has been successfully curbed.
According to a recent report of the Shanghai municipal water bureau, the surface of the city sank around 10 millimeters in the past few years, only one tenth of land subsidence in the worst year.
This coastal metropolis started exploiting its groundwater in 1860 and the surface of Shanghai has been continuously sinking in the past eight-plus decades since 1921.
By 1965, the surface of urban Shanghai sank 1.69 meters, the period of the fastest subsidence in the city's history.
Local experts attributed fast land sinkage to excessive tapping of groundwater, civil engineering, construction of skyscrapers and geological changes.
To slow the rate of land subsidence, the Shanghai Municipal Government has cut down groundwater consumption, built tap water networks in rural areas and re-injected running water to underground layer.
Currently, Shanghai extracts 96.35 million cubic meters of groundwater annually, or 46 percent of the peak consumption year.
(Xinhua News Agency February 11, 2004)
