Shanghai will significantly raise the price of underground water this year to encourage people and companies to use tap water where accessible, and reduce the waste of underground resources.

The price increase is part of city plans to cut the amount of underground water used in the city by 2010 to one-third of the amount used last year in order to control land subsidence in Shanghai, according to the Shanghai Water Authority.

The price increase will mainly affect small water plants in the suburbs that depend on deep wells. Some beverage makers will be given priority to use underground water.

"We will push further construction of big water plants in the suburbs or increase supply from downtown water plants," the water authority said in a written statement released yesterday.

Authority officials are still in discussions with local price authorities about increasing the price of deep-well water. The specific plan hasn't been finalized yet, but according to a preliminary plan the rate is likely to be doubled for both residential and industrial users.

The city has set a quota on the amount of underground water used this year. The quota was set at 68 million cubic meters, of which 9 million cubic meters is allocated for areas within the Outer Ring Road.

Baoshan District, which once depended heavily on small water plants that draw water from deep well, has banned the use of all deep wells this year.

The city also plans to pump 15 million cubic meters back underground this year to counter land subsidence. About 10 million cubic meters of that water will be pumped underground in the city's central business district.

Last year, the city consumed 74.52 million cubic meters of underground water. By 2010, the city will use less than 25 million cubic meters.

The city is trying to control subsidence to less than 5 millimeters a year by 2010. The average land subsidence was 8.7 millimeters in 2004, mainly due to overuse of underground water resources and the rapid construction of skyscrapers, according to a geological report from a local research institute.

Excessive subsidence could damage underground infrastructure, such as subway tunnels, pipes and flood management systems.

The city's subsidence is most noticeable in areas near the Puxi section of the Nanpu Bridge and the Lujiazui financial district in Pudong.

(Shanghai Daily February 24, 2006)