A seven-meter-long crack has surfaced on the road near Shanghai World Financial Center on February 16. Photo: Oriental Morning Post.
On February 19, the State Council approved China's Land Subsidence Prevention Project, an endeavor that has been revised by ten ministries, according to officials.
According to research, more than 50 counties in China are slowly sinking. Experts compare land sinking to a chronic disease, that goes unnoticed but remains dangerous.
Latest reports:
◆Vedio News:
Land subsidence: the weight earth can't bear, Feb 20, CCTV
◆
Gov't Approves Land Subsidence Prevention Project, Feb 20, CRI
Current situation:
More than
50 county-areas in China are suffering from land subsidence, while the total area of land lower than
200 millimeters has reached
79,000 square kilometers.
Parts of the cities may be submerged under water in the future.
The areas which have the most severe situations are
the Yangtze River Delta, the North China Plain and the Fen-Wei basin.
According to the China Geological Survey, in the past decades, the economic losses caused by land subsidence in the Yangtze River Delta have totaled up to
315 billion yuan. The economic losses of the North China Plain amount to
332.8 billion yuan.
Beijing, Capital of China, the North China Plain:
Due to land subsidence caused by excessive groundwater pumping, many sinkholes appeared in the street of Beijing in recent years.
◆
Streets succumb to sinkholes, Jun 28 2011, Global Times
◆
Fengtai sinkhole consumes truck, Apr 27 2011, Global Times
Shanghai, economic centre, the Yangtze River Delta:
Land subsidence in Shanghai has mainly been induced by the city's rapidly emerging skyscrapers. The lan surface of Shanghai is below the sea level now.
◆
Cracks pose 'no safety risks to area', Feb 16 2012, Global Times
◆
Shanghai weighted down with skyscrapers, Nov 16 2011, Ecns.cn
Cangzhou, Hebei Province, the North China Plain:
Cangzhou stays in a severe situation due to the overuse of groundwater. A three-stories-tall building in Cangzhou was forced to rebuild as a fountain because of the land subsidence.
◆
2.4 meters' land subsidence of Cangzhou in 40 years, Oct 31 2011, Hebei Youth Daily
Xi'an, provincial capital of Shaanxi Province, the Fen-Wei basin:
Land subsidence of Xi’an is mainly caused by overuse of groundwater, which results in the incline of Big Wild Goose Pogoda, an ancient temple.
◆
Big Wild Goose Pogoda leans for more than 1,000 minimeters, Feb 20 2012, CCTV
Influences:
◆Drainage system damage:
The land subsidence presses the drainage system underground, which easily makes the system stop working. The ability of flood prevention in the city decreases through this way. The floods in Bangkok were a result of this similar situation.
◆The damage to facilities and buildings:
The land subsidence results in foundation deformation of buildings and their infrastructure, such as subways and highways. Many important facilities and construction, including some historical and cultural relics of some cities have been gradually destroyed.
◆A direct risk to human life:
The damage of the cities caused by land subsidence has placed peoples’ lives at risk. Take the cracks and sinkholes for example. Pedestrians and cars may fall into them at anytime completely unnoticed.
Causes:
◆Excessive groundwater pumping:
Groundwater is the main source of domestic water in many cities throughout China. Groundwater accounted for 72 and 66 per cent of the water supply for cities within the dry northern and northwestern regions of the country. However, overused groundwater supplies are the chief cause of land subsidence.
◆City construction:
With the rapid development of cities in China, different construction, especially subway and skyscraper construction, has become another cause behind land subsidence. For instance, in Shanghai, more than 3,000 buildings are over 18 stories tall or taller, while another 3,000 are under construction. And some 100 of the existing buildings in the city exceed 100 meters in height.
◆Other causes:
The non-stop mining in the cities throughout the North China Plain has also caused land subsidence in that area. And the diffluent soil in some cities on the seaside such as Shanghai is a natural factor.
◆Central Government approves Land Subsidence Prevention Project:
On February 19, China's Land Subsidence Prevention Project, an endeavor revised by ten ministries, was approved by the State Council. This is China's first countrywide effort to prevent land subsidence, a process where a segment of land experiences a decrease in elevation due to either natural or human-induced causes.
Also, in November of last year, the State Council started to create a national monitoring system designed to keep an eye on underground water.
◆Local Government: control the use of underground water:
Local city and provincial governments suffering from the most severe subsidence have also started imposing strict measures on the use of groundwater in recent years.
Jiangsu Province, for instance, has decided to close all deep-water wells before the end of this year throughout the fastest sinking areas of Suzhou, Changzhou and Wuxi, and the pumping of groundwater in other areas will be strictly rationed, said Vice-governor Huang Lixin.